diff options
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 3136 |
1 files changed, 1229 insertions, 1907 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 13cdab3b4c48..3332bbb5d5cf 100644 --- a/kernel/sched.c +++ b/kernel/sched.c | |||
| @@ -16,13 +16,19 @@ | |||
| 16 | * by Davide Libenzi, preemptible kernel bits by Robert Love. | 16 | * by Davide Libenzi, preemptible kernel bits by Robert Love. |
| 17 | * 2003-09-03 Interactivity tuning by Con Kolivas. | 17 | * 2003-09-03 Interactivity tuning by Con Kolivas. |
| 18 | * 2004-04-02 Scheduler domains code by Nick Piggin | 18 | * 2004-04-02 Scheduler domains code by Nick Piggin |
| 19 | * 2007-04-15 Work begun on replacing all interactivity tuning with a | ||
| 20 | * fair scheduling design by Con Kolivas. | ||
| 21 | * 2007-05-05 Load balancing (smp-nice) and other improvements | ||
| 22 | * by Peter Williams | ||
| 23 | * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith | ||
| 24 | * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri | ||
| 19 | */ | 25 | */ |
| 20 | 26 | ||
| 21 | #include <linux/mm.h> | 27 | #include <linux/mm.h> |
| 22 | #include <linux/module.h> | 28 | #include <linux/module.h> |
| 23 | #include <linux/nmi.h> | 29 | #include <linux/nmi.h> |
| 24 | #include <linux/init.h> | 30 | #include <linux/init.h> |
| 25 | #include <asm/uaccess.h> | 31 | #include <linux/uaccess.h> |
| 26 | #include <linux/highmem.h> | 32 | #include <linux/highmem.h> |
| 27 | #include <linux/smp_lock.h> | 33 | #include <linux/smp_lock.h> |
| 28 | #include <asm/mmu_context.h> | 34 | #include <asm/mmu_context.h> |
| @@ -53,9 +59,9 @@ | |||
| 53 | #include <linux/kprobes.h> | 59 | #include <linux/kprobes.h> |
| 54 | #include <linux/delayacct.h> | 60 | #include <linux/delayacct.h> |
| 55 | #include <linux/reciprocal_div.h> | 61 | #include <linux/reciprocal_div.h> |
| 62 | #include <linux/unistd.h> | ||
| 56 | 63 | ||
| 57 | #include <asm/tlb.h> | 64 | #include <asm/tlb.h> |
| 58 | #include <asm/unistd.h> | ||
| 59 | 65 | ||
| 60 | /* | 66 | /* |
| 61 | * Scheduler clock - returns current time in nanosec units. | 67 | * Scheduler clock - returns current time in nanosec units. |
| @@ -91,6 +97,9 @@ unsigned long long __attribute__((weak)) sched_clock(void) | |||
| 91 | #define NS_TO_JIFFIES(TIME) ((TIME) / (1000000000 / HZ)) | 97 | #define NS_TO_JIFFIES(TIME) ((TIME) / (1000000000 / HZ)) |
| 92 | #define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) | 98 | #define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) |
| 93 | 99 | ||
| 100 | #define NICE_0_LOAD SCHED_LOAD_SCALE | ||
| 101 | #define NICE_0_SHIFT SCHED_LOAD_SHIFT | ||
| 102 | |||
| 94 | /* | 103 | /* |
| 95 | * These are the 'tuning knobs' of the scheduler: | 104 | * These are the 'tuning knobs' of the scheduler: |
| 96 | * | 105 | * |
| @@ -100,87 +109,6 @@ unsigned long long __attribute__((weak)) sched_clock(void) | |||
| 100 | */ | 109 | */ |
| 101 | #define MIN_TIMESLICE max(5 * HZ / 1000, 1) | 110 | #define MIN_TIMESLICE max(5 * HZ / 1000, 1) |
| 102 | #define DEF_TIMESLICE (100 * HZ / 1000) | 111 | #define DEF_TIMESLICE (100 * HZ / 1000) |
| 103 | #define ON_RUNQUEUE_WEIGHT 30 | ||
| 104 | #define CHILD_PENALTY 95 | ||
| 105 | #define PARENT_PENALTY 100 | ||
| 106 | #define EXIT_WEIGHT 3 | ||
| 107 | #define PRIO_BONUS_RATIO 25 | ||
| 108 | #define MAX_BONUS (MAX_USER_PRIO * PRIO_BONUS_RATIO / 100) | ||
| 109 | #define INTERACTIVE_DELTA 2 | ||
| 110 | #define MAX_SLEEP_AVG (DEF_TIMESLICE * MAX_BONUS) | ||
| 111 | #define STARVATION_LIMIT (MAX_SLEEP_AVG) | ||
| 112 | #define NS_MAX_SLEEP_AVG (JIFFIES_TO_NS(MAX_SLEEP_AVG)) | ||
| 113 | |||
| 114 | /* | ||
| 115 | * If a task is 'interactive' then we reinsert it in the active | ||
| 116 | * array after it has expired its current timeslice. (it will not | ||
| 117 | * continue to run immediately, it will still roundrobin with | ||
| 118 | * other interactive tasks.) | ||
| 119 | * | ||
| 120 | * This part scales the interactivity limit depending on niceness. | ||
| 121 | * | ||
| 122 | * We scale it linearly, offset by the INTERACTIVE_DELTA delta. | ||
| 123 | * Here are a few examples of different nice levels: | ||
| 124 | * | ||
| 125 | * TASK_INTERACTIVE(-20): [1,1,1,1,1,1,1,1,1,0,0] | ||
| 126 | * TASK_INTERACTIVE(-10): [1,1,1,1,1,1,1,0,0,0,0] | ||
| 127 | * TASK_INTERACTIVE( 0): [1,1,1,1,0,0,0,0,0,0,0] | ||
| 128 | * TASK_INTERACTIVE( 10): [1,1,0,0,0,0,0,0,0,0,0] | ||
| 129 | * TASK_INTERACTIVE( 19): [0,0,0,0,0,0,0,0,0,0,0] | ||
| 130 | * | ||
| 131 | * (the X axis represents the possible -5 ... 0 ... +5 dynamic | ||
| 132 | * priority range a task can explore, a value of '1' means the | ||
| 133 | * task is rated interactive.) | ||
| 134 | * | ||
| 135 | * Ie. nice +19 tasks can never get 'interactive' enough to be | ||
| 136 | * reinserted into the active array. And only heavily CPU-hog nice -20 | ||
| 137 | * tasks will be expired. Default nice 0 tasks are somewhere between, | ||
| 138 | * it takes some effort for them to get interactive, but it's not | ||
| 139 | * too hard. | ||
| 140 | */ | ||
| 141 | |||
| 142 | #define CURRENT_BONUS(p) \ | ||
| 143 | (NS_TO_JIFFIES((p)->sleep_avg) * MAX_BONUS / \ | ||
| 144 | MAX_SLEEP_AVG) | ||
| 145 | |||
| 146 | #define GRANULARITY (10 * HZ / 1000 ? : 1) | ||
| 147 | |||
| 148 | #ifdef CONFIG_SMP | ||
| 149 | #define TIMESLICE_GRANULARITY(p) (GRANULARITY * \ | ||
| 150 | (1 << (((MAX_BONUS - CURRENT_BONUS(p)) ? : 1) - 1)) * \ | ||
| 151 | num_online_cpus()) | ||
| 152 | #else | ||
| 153 | #define TIMESLICE_GRANULARITY(p) (GRANULARITY * \ | ||
| 154 | (1 << (((MAX_BONUS - CURRENT_BONUS(p)) ? : 1) - 1))) | ||
| 155 | #endif | ||
| 156 | |||
| 157 | #define SCALE(v1,v1_max,v2_max) \ | ||
| 158 | (v1) * (v2_max) / (v1_max) | ||
| 159 | |||
| 160 | #define DELTA(p) \ | ||
| 161 | (SCALE(TASK_NICE(p) + 20, 40, MAX_BONUS) - 20 * MAX_BONUS / 40 + \ | ||
| 162 | INTERACTIVE_DELTA) | ||
| 163 | |||
| 164 | #define TASK_INTERACTIVE(p) \ | ||
| 165 | ((p)->prio <= (p)->static_prio - DELTA(p)) | ||
| 166 | |||
| 167 | #define INTERACTIVE_SLEEP(p) \ | ||
| 168 | (JIFFIES_TO_NS(MAX_SLEEP_AVG * \ | ||
| 169 | (MAX_BONUS / 2 + DELTA((p)) + 1) / MAX_BONUS - 1)) | ||
| 170 | |||
| 171 | #define TASK_PREEMPTS_CURR(p, rq) \ | ||
| 172 | ((p)->prio < (rq)->curr->prio) | ||
| 173 | |||
| 174 | #define SCALE_PRIO(x, prio) \ | ||
| 175 | max(x * (MAX_PRIO - prio) / (MAX_USER_PRIO / 2), MIN_TIMESLICE) | ||
| 176 | |||
| 177 | static unsigned int static_prio_timeslice(int static_prio) | ||
| 178 | { | ||
| 179 | if (static_prio < NICE_TO_PRIO(0)) | ||
| 180 | return SCALE_PRIO(DEF_TIMESLICE * 4, static_prio); | ||
| 181 | else | ||
| 182 | return SCALE_PRIO(DEF_TIMESLICE, static_prio); | ||
| 183 | } | ||
| 184 | 112 | ||
| 185 | #ifdef CONFIG_SMP | 113 | #ifdef CONFIG_SMP |
| 186 | /* | 114 | /* |
| @@ -203,28 +131,87 @@ static inline void sg_inc_cpu_power(struct sched_group *sg, u32 val) | |||
| 203 | } | 131 | } |
| 204 | #endif | 132 | #endif |
| 205 | 133 | ||
| 134 | #define SCALE_PRIO(x, prio) \ | ||
| 135 | max(x * (MAX_PRIO - prio) / (MAX_USER_PRIO / 2), MIN_TIMESLICE) | ||
| 136 | |||
| 206 | /* | 137 | /* |
| 207 | * task_timeslice() scales user-nice values [ -20 ... 0 ... 19 ] | 138 | * static_prio_timeslice() scales user-nice values [ -20 ... 0 ... 19 ] |
| 208 | * to time slice values: [800ms ... 100ms ... 5ms] | 139 | * to time slice values: [800ms ... 100ms ... 5ms] |
| 209 | * | ||
| 210 | * The higher a thread's priority, the bigger timeslices | ||
| 211 | * it gets during one round of execution. But even the lowest | ||
| 212 | * priority thread gets MIN_TIMESLICE worth of execution time. | ||
| 213 | */ | 140 | */ |
| 141 | static unsigned int static_prio_timeslice(int static_prio) | ||
| 142 | { | ||
| 143 | if (static_prio == NICE_TO_PRIO(19)) | ||
| 144 | return 1; | ||
| 214 | 145 | ||
| 215 | static inline unsigned int task_timeslice(struct task_struct *p) | 146 | if (static_prio < NICE_TO_PRIO(0)) |
| 147 | return SCALE_PRIO(DEF_TIMESLICE * 4, static_prio); | ||
| 148 | else | ||
| 149 | return SCALE_PRIO(DEF_TIMESLICE, static_prio); | ||
| 150 | } | ||
| 151 | |||
| 152 | static inline int rt_policy(int policy) | ||
| 153 | { | ||
| 154 | if (unlikely(policy == SCHED_FIFO) || unlikely(policy == SCHED_RR)) | ||
| 155 | return 1; | ||
| 156 | return 0; | ||
| 157 | } | ||
| 158 | |||
| 159 | static inline int task_has_rt_policy(struct task_struct *p) | ||
| 216 | { | 160 | { |
| 217 | return static_prio_timeslice(p->static_prio); | 161 | return rt_policy(p->policy); |
| 218 | } | 162 | } |
| 219 | 163 | ||
| 220 | /* | 164 | /* |
| 221 | * These are the runqueue data structures: | 165 | * This is the priority-queue data structure of the RT scheduling class: |
| 222 | */ | 166 | */ |
| 167 | struct rt_prio_array { | ||
| 168 | DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ | ||
| 169 | struct list_head queue[MAX_RT_PRIO]; | ||
| 170 | }; | ||
| 223 | 171 | ||
| 224 | struct prio_array { | 172 | struct load_stat { |
| 225 | unsigned int nr_active; | 173 | struct load_weight load; |
| 226 | DECLARE_BITMAP(bitmap, MAX_PRIO+1); /* include 1 bit for delimiter */ | 174 | u64 load_update_start, load_update_last; |
| 227 | struct list_head queue[MAX_PRIO]; | 175 | unsigned long delta_fair, delta_exec, delta_stat; |
| 176 | }; | ||
| 177 | |||
| 178 | /* CFS-related fields in a runqueue */ | ||
| 179 | struct cfs_rq { | ||
| 180 | struct load_weight load; | ||
| 181 | unsigned long nr_running; | ||
| 182 | |||
| 183 | s64 fair_clock; | ||
| 184 | u64 exec_clock; | ||
| 185 | s64 wait_runtime; | ||
| 186 | u64 sleeper_bonus; | ||
| 187 | unsigned long wait_runtime_overruns, wait_runtime_underruns; | ||
| 188 | |||
| 189 | struct rb_root tasks_timeline; | ||
| 190 | struct rb_node *rb_leftmost; | ||
| 191 | struct rb_node *rb_load_balance_curr; | ||
| 192 | #ifdef CONFIG_FAIR_GROUP_SCHED | ||
| 193 | /* 'curr' points to currently running entity on this cfs_rq. | ||
| 194 | * It is set to NULL otherwise (i.e when none are currently running). | ||
| 195 | */ | ||
| 196 | struct sched_entity *curr; | ||
| 197 | struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ | ||
| 198 | |||
| 199 | /* leaf cfs_rqs are those that hold tasks (lowest schedulable entity in | ||
| 200 | * a hierarchy). Non-leaf lrqs hold other higher schedulable entities | ||
| 201 | * (like users, containers etc.) | ||
| 202 | * | ||
| 203 | * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This | ||
| 204 | * list is used during load balance. | ||
| 205 | */ | ||
| 206 | struct list_head leaf_cfs_rq_list; /* Better name : task_cfs_rq_list? */ | ||
| 207 | #endif | ||
| 208 | }; | ||
| 209 | |||
| 210 | /* Real-Time classes' related field in a runqueue: */ | ||
| 211 | struct rt_rq { | ||
| 212 | struct rt_prio_array active; | ||
| 213 | int rt_load_balance_idx; | ||
| 214 | struct list_head *rt_load_balance_head, *rt_load_balance_curr; | ||
| 228 | }; | 215 | }; |
| 229 | 216 | ||
| 230 | /* | 217 | /* |
| @@ -235,22 +222,28 @@ struct prio_array { | |||
| 235 | * acquire operations must be ordered by ascending &runqueue. | 222 | * acquire operations must be ordered by ascending &runqueue. |
| 236 | */ | 223 | */ |
| 237 | struct rq { | 224 | struct rq { |
| 238 | spinlock_t lock; | 225 | spinlock_t lock; /* runqueue lock */ |
| 239 | 226 | ||
| 240 | /* | 227 | /* |
| 241 | * nr_running and cpu_load should be in the same cacheline because | 228 | * nr_running and cpu_load should be in the same cacheline because |
| 242 | * remote CPUs use both these fields when doing load calculation. | 229 | * remote CPUs use both these fields when doing load calculation. |
| 243 | */ | 230 | */ |
| 244 | unsigned long nr_running; | 231 | unsigned long nr_running; |
| 245 | unsigned long raw_weighted_load; | 232 | #define CPU_LOAD_IDX_MAX 5 |
| 246 | #ifdef CONFIG_SMP | 233 | unsigned long cpu_load[CPU_LOAD_IDX_MAX]; |
| 247 | unsigned long cpu_load[3]; | ||
| 248 | unsigned char idle_at_tick; | 234 | unsigned char idle_at_tick; |
| 249 | #ifdef CONFIG_NO_HZ | 235 | #ifdef CONFIG_NO_HZ |
| 250 | unsigned char in_nohz_recently; | 236 | unsigned char in_nohz_recently; |
| 251 | #endif | 237 | #endif |
| 238 | struct load_stat ls; /* capture load from *all* tasks on this cpu */ | ||
| 239 | unsigned long nr_load_updates; | ||
| 240 | u64 nr_switches; | ||
| 241 | |||
| 242 | struct cfs_rq cfs; | ||
| 243 | #ifdef CONFIG_FAIR_GROUP_SCHED | ||
| 244 | struct list_head leaf_cfs_rq_list; /* list of leaf cfs_rq on this cpu */ | ||
| 252 | #endif | 245 | #endif |
| 253 | unsigned long long nr_switches; | 246 | struct rt_rq rt; |
| 254 | 247 | ||
| 255 | /* | 248 | /* |
| 256 | * This is part of a global counter where only the total sum | 249 | * This is part of a global counter where only the total sum |
| @@ -260,14 +253,18 @@ struct rq { | |||
| 260 | */ | 253 | */ |
| 261 | unsigned long nr_uninterruptible; | 254 | unsigned long nr_uninterruptible; |
| 262 | 255 | ||
| 263 | unsigned long expired_timestamp; | ||
| 264 | /* Cached timestamp set by update_cpu_clock() */ | ||
| 265 | unsigned long long most_recent_timestamp; | ||
| 266 | struct task_struct *curr, *idle; | 256 | struct task_struct *curr, *idle; |
| 267 | unsigned long next_balance; | 257 | unsigned long next_balance; |
| 268 | struct mm_struct *prev_mm; | 258 | struct mm_struct *prev_mm; |
| 269 | struct prio_array *active, *expired, arrays[2]; | 259 | |
| 270 | int best_expired_prio; | 260 | u64 clock, prev_clock_raw; |
| 261 | s64 clock_max_delta; | ||
| 262 | |||
| 263 | unsigned int clock_warps, clock_overflows; | ||
| 264 | unsigned int clock_unstable_events; | ||
| 265 | |||
| 266 | struct sched_class *load_balance_class; | ||
| 267 | |||
| 271 | atomic_t nr_iowait; | 268 | atomic_t nr_iowait; |
| 272 | 269 | ||
| 273 | #ifdef CONFIG_SMP | 270 | #ifdef CONFIG_SMP |
| @@ -307,6 +304,11 @@ struct rq { | |||
| 307 | static DEFINE_PER_CPU(struct rq, runqueues) ____cacheline_aligned_in_smp; | 304 | static DEFINE_PER_CPU(struct rq, runqueues) ____cacheline_aligned_in_smp; |
| 308 | static DEFINE_MUTEX(sched_hotcpu_mutex); | 305 | static DEFINE_MUTEX(sched_hotcpu_mutex); |
| 309 | 306 | ||
| 307 | static inline void check_preempt_curr(struct rq *rq, struct task_struct *p) | ||
| 308 | { | ||
| 309 | rq->curr->sched_class->check_preempt_curr(rq, p); | ||
| 310 | } | ||
| 311 | |||
| 310 | static inline int cpu_of(struct rq *rq) | 312 | static inline int cpu_of(struct rq *rq) |
| 311 | { | 313 | { |
| 312 | #ifdef CONFIG_SMP | 314 | #ifdef CONFIG_SMP |
| @@ -317,6 +319,52 @@ static inline int cpu_of(struct rq *rq) | |||
| 317 | } | 319 | } |
| 318 | 320 | ||
| 319 | /* | 321 | /* |
| 322 | * Per-runqueue clock, as finegrained as the platform can give us: | ||
| 323 | */ | ||
| 324 | static unsigned long long __rq_clock(struct rq *rq) | ||
| 325 | { | ||
| 326 | u64 prev_raw = rq->prev_clock_raw; | ||
| 327 | u64 now = sched_clock(); | ||
| 328 | s64 delta = now - prev_raw; | ||
| 329 | u64 clock = rq->clock; | ||
| 330 | |||
| 331 | /* | ||
| 332 | * Protect against sched_clock() occasionally going backwards: | ||
| 333 | */ | ||
| 334 | if (unlikely(delta < 0)) { | ||
| 335 | clock++; | ||
| 336 | rq->clock_warps++; | ||
| 337 | } else { | ||
| 338 | /* | ||
| 339 | * Catch too large forward jumps too: | ||
| 340 | */ | ||
| 341 | if (unlikely(delta > 2*TICK_NSEC)) { | ||
| 342 | clock++; | ||
| 343 | rq->clock_overflows++; | ||
| 344 | } else { | ||
| 345 | if (unlikely(delta > rq->clock_max_delta)) | ||
| 346 | rq->clock_max_delta = delta; | ||
| 347 | clock += delta; | ||
| 348 | } | ||
| 349 | } | ||
| 350 | |||
| 351 | rq->prev_clock_raw = now; | ||
| 352 | rq->clock = clock; | ||
| 353 | |||
| 354 | return clock; | ||
| 355 | } | ||
| 356 | |||
| 357 | static inline unsigned long long rq_clock(struct rq *rq) | ||
| 358 | { | ||
| 359 | int this_cpu = smp_processor_id(); | ||
| 360 | |||
| 361 | if (this_cpu == cpu_of(rq)) | ||
| 362 | return __rq_clock(rq); | ||
| 363 | |||
| 364 | return rq->clock; | ||
| 365 | } | ||
| 366 | |||
| 367 | /* | ||
| 320 | * The domain tree (rq->sd) is protected by RCU's quiescent state transition. | 368 | * The domain tree (rq->sd) is protected by RCU's quiescent state transition. |
| 321 | * See detach_destroy_domains: synchronize_sched for details. | 369 | * See detach_destroy_domains: synchronize_sched for details. |
| 322 | * | 370 | * |
| @@ -331,6 +379,18 @@ static inline int cpu_of(struct rq *rq) | |||
| 331 | #define task_rq(p) cpu_rq(task_cpu(p)) | 379 | #define task_rq(p) cpu_rq(task_cpu(p)) |
| 332 | #define cpu_curr(cpu) (cpu_rq(cpu)->curr) | 380 | #define cpu_curr(cpu) (cpu_rq(cpu)->curr) |
| 333 | 381 | ||
| 382 | #ifdef CONFIG_FAIR_GROUP_SCHED | ||
| 383 | /* Change a task's ->cfs_rq if it moves across CPUs */ | ||
| 384 | static inline void set_task_cfs_rq(struct task_struct *p) | ||
| 385 | { | ||
| 386 | p->se.cfs_rq = &task_rq(p)->cfs; | ||
| 387 | } | ||
| 388 | #else | ||
| 389 | static inline void set_task_cfs_rq(struct task_struct *p) | ||
| 390 | { | ||
| 391 | } | ||
| 392 | #endif | ||
| 393 | |||
| 334 | #ifndef prepare_arch_switch | 394 | #ifndef prepare_arch_switch |
| 335 | # define prepare_arch_switch(next) do { } while (0) | 395 | # define prepare_arch_switch(next) do { } while (0) |
| 336 | #endif | 396 | #endif |
| @@ -460,134 +520,6 @@ static inline void task_rq_unlock(struct rq *rq, unsigned long *flags) | |||
| 460 | spin_unlock_irqrestore(&rq->lock, *flags); | 520 | spin_unlock_irqrestore(&rq->lock, *flags); |
| 461 | } | 521 | } |
| 462 | 522 | ||
| 463 | #ifdef CONFIG_SCHEDSTATS | ||
| 464 | /* | ||
| 465 | * bump this up when changing the output format or the meaning of an existing | ||
| 466 | * format, so that tools can adapt (or abort) | ||
| 467 | */ | ||
| 468 | #define SCHEDSTAT_VERSION 14 | ||
| 469 | |||
| 470 | static int show_schedstat(struct seq_file *seq, void *v) | ||
| 471 | { | ||
| 472 | int cpu; | ||
| 473 | |||
| 474 | seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION); | ||
| 475 | seq_printf(seq, "timestamp %lu\n", jiffies); | ||
| 476 | for_each_online_cpu(cpu) { | ||
| 477 | struct rq *rq = cpu_rq(cpu); | ||
| 478 | #ifdef CONFIG_SMP | ||
| 479 | struct sched_domain *sd; | ||
| 480 | int dcnt = 0; | ||
| 481 | #endif | ||
| 482 | |||
| 483 | /* runqueue-specific stats */ | ||
| 484 | seq_printf(seq, | ||
| 485 | "cpu%d %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu", | ||
| 486 | cpu, rq->yld_both_empty, | ||
| 487 | rq->yld_act_empty, rq->yld_exp_empty, rq->yld_cnt, | ||
| 488 | rq->sched_switch, rq->sched_cnt, rq->sched_goidle, | ||
| 489 | rq->ttwu_cnt, rq->ttwu_local, | ||
| 490 | rq->rq_sched_info.cpu_time, | ||
| 491 | rq->rq_sched_info.run_delay, rq->rq_sched_info.pcnt); | ||
| 492 | |||
| 493 | seq_printf(seq, "\n"); | ||
| 494 | |||
| 495 | #ifdef CONFIG_SMP | ||
| 496 | /* domain-specific stats */ | ||
| 497 | preempt_disable(); | ||
| 498 | for_each_domain(cpu, sd) { | ||
| 499 | enum idle_type itype; | ||
| 500 | char mask_str[NR_CPUS]; | ||
| 501 | |||
| 502 | cpumask_scnprintf(mask_str, NR_CPUS, sd->span); | ||
| 503 | seq_printf(seq, "domain%d %s", dcnt++, mask_str); | ||
| 504 | for (itype = SCHED_IDLE; itype < MAX_IDLE_TYPES; | ||
| 505 | itype++) { | ||
| 506 | seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu " | ||
| 507 | "%lu", | ||
| 508 | sd->lb_cnt[itype], | ||
| 509 | sd->lb_balanced[itype], | ||
| 510 | sd->lb_failed[itype], | ||
| 511 | sd->lb_imbalance[itype], | ||
| 512 | sd->lb_gained[itype], | ||
| 513 | sd->lb_hot_gained[itype], | ||
| 514 | sd->lb_nobusyq[itype], | ||
| 515 | sd->lb_nobusyg[itype]); | ||
| 516 | } | ||
| 517 | seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu %lu %lu" | ||
| 518 | " %lu %lu %lu\n", | ||
| 519 | sd->alb_cnt, sd->alb_failed, sd->alb_pushed, | ||
| 520 | sd->sbe_cnt, sd->sbe_balanced, sd->sbe_pushed, | ||
| 521 | sd->sbf_cnt, sd->sbf_balanced, sd->sbf_pushed, | ||
| 522 | sd->ttwu_wake_remote, sd->ttwu_move_affine, | ||
| 523 | sd->ttwu_move_balance); | ||
| 524 | } | ||
| 525 | preempt_enable(); | ||
| 526 | #endif | ||
| 527 | } | ||
| 528 | return 0; | ||
| 529 | } | ||
| 530 | |||
| 531 | static int schedstat_open(struct inode *inode, struct file *file) | ||
| 532 | { | ||
| 533 | unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32); | ||
| 534 | char *buf = kmalloc(size, GFP_KERNEL); | ||
| 535 | struct seq_file *m; | ||
| 536 | int res; | ||
| 537 | |||
| 538 | if (!buf) | ||
| 539 | return -ENOMEM; | ||
| 540 | res = single_open(file, show_schedstat, NULL); | ||
| 541 | if (!res) { | ||
| 542 | m = file->private_data; | ||
| 543 | m->buf = buf; | ||
| 544 | m->size = size; | ||
| 545 | } else | ||
| 546 | kfree(buf); | ||
| 547 | return res; | ||
| 548 | } | ||
| 549 | |||
| 550 | const struct file_operations proc_schedstat_operations = { | ||
| 551 | .open = schedstat_open, | ||
| 552 | .read = seq_read, | ||
| 553 | .llseek = seq_lseek, | ||
| 554 | .release = single_release, | ||
| 555 | }; | ||
| 556 | |||
| 557 | /* | ||
| 558 | * Expects runqueue lock to be held for atomicity of update | ||
| 559 | */ | ||
| 560 | static inline void | ||
| 561 | rq_sched_info_arrive(struct rq *rq, unsigned long delta_jiffies) | ||
| 562 | { | ||
| 563 | if (rq) { | ||
| 564 | rq->rq_sched_info.run_delay += delta_jiffies; | ||
| 565 | rq->rq_sched_info.pcnt++; | ||
| 566 | } | ||
| 567 | } | ||
| 568 | |||
| 569 | /* | ||
| 570 | * Expects runqueue lock to be held for atomicity of update | ||
| 571 | */ | ||
| 572 | static inline void | ||
| 573 | rq_sched_info_depart(struct rq *rq, unsigned long delta_jiffies) | ||
| 574 | { | ||
| 575 | if (rq) | ||
| 576 | rq->rq_sched_info.cpu_time += delta_jiffies; | ||
| 577 | } | ||
| 578 | # define schedstat_inc(rq, field) do { (rq)->field++; } while (0) | ||
| 579 | # define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0) | ||
| 580 | #else /* !CONFIG_SCHEDSTATS */ | ||
| 581 | static inline void | ||
| 582 | rq_sched_info_arrive(struct rq *rq, unsigned long delta_jiffies) | ||
| 583 | {} | ||
| 584 | static inline void | ||
| 585 | rq_sched_info_depart(struct rq *rq, unsigned long delta_jiffies) | ||
| 586 | {} | ||
| 587 | # define schedstat_inc(rq, field) do { } while (0) | ||
| 588 | # define schedstat_add(rq, field, amt) do { } while (0) | ||
| 589 | #endif | ||
| 590 | |||
| 591 | /* | 523 | /* |
| 592 | * this_rq_lock - lock this runqueue and disable interrupts. | 524 | * this_rq_lock - lock this runqueue and disable interrupts. |
| 593 | */ | 525 | */ |
| @@ -603,177 +535,172 @@ static inline struct rq *this_rq_lock(void) | |||
| 603 | return rq; | 535 | return rq; |
| 604 | } | 536 | } |
| 605 | 537 | ||
| 606 | #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) | ||
| 607 | /* | 538 | /* |
| 608 | * Called when a process is dequeued from the active array and given | 539 | * CPU frequency is/was unstable - start new by setting prev_clock_raw: |
| 609 | * the cpu. We should note that with the exception of interactive | ||
| 610 | * tasks, the expired queue will become the active queue after the active | ||
| 611 | * queue is empty, without explicitly dequeuing and requeuing tasks in the | ||
| 612 | * expired queue. (Interactive tasks may be requeued directly to the | ||
| 613 | * active queue, thus delaying tasks in the expired queue from running; | ||
| 614 | * see scheduler_tick()). | ||
| 615 | * | ||
| 616 | * This function is only called from sched_info_arrive(), rather than | ||
| 617 | * dequeue_task(). Even though a task may be queued and dequeued multiple | ||
| 618 | * times as it is shuffled about, we're really interested in knowing how | ||
| 619 | * long it was from the *first* time it was queued to the time that it | ||
| 620 | * finally hit a cpu. | ||
| 621 | */ | 540 | */ |
| 622 | static inline void sched_info_dequeued(struct task_struct *t) | 541 | void sched_clock_unstable_event(void) |
| 623 | { | 542 | { |
| 624 | t->sched_info.last_queued = 0; | 543 | unsigned long flags; |
| 544 | struct rq *rq; | ||
| 545 | |||
| 546 | rq = task_rq_lock(current, &flags); | ||
| 547 | rq->prev_clock_raw = sched_clock(); | ||
| 548 | rq->clock_unstable_events++; | ||
| 549 | task_rq_unlock(rq, &flags); | ||
| 625 | } | 550 | } |
| 626 | 551 | ||
| 627 | /* | 552 | /* |
| 628 | * Called when a task finally hits the cpu. We can now calculate how | 553 | * resched_task - mark a task 'to be rescheduled now'. |
| 629 | * long it was waiting to run. We also note when it began so that we | 554 | * |
| 630 | * can keep stats on how long its timeslice is. | 555 | * On UP this means the setting of the need_resched flag, on SMP it |
| 556 | * might also involve a cross-CPU call to trigger the scheduler on | ||
| 557 | * the target CPU. | ||
| 631 | */ | 558 | */ |
| 632 | static void sched_info_arrive(struct task_struct *t) | 559 | #ifdef CONFIG_SMP |
| 560 | |||
| 561 | #ifndef tsk_is_polling | ||
| 562 | #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) | ||
| 563 | #endif | ||
| 564 | |||
| 565 | static void resched_task(struct task_struct *p) | ||
| 633 | { | 566 | { |
| 634 | unsigned long now = jiffies, delta_jiffies = 0; | 567 | int cpu; |
| 635 | 568 | ||
| 636 | if (t->sched_info.last_queued) | 569 | assert_spin_locked(&task_rq(p)->lock); |
| 637 | delta_jiffies = now - t->sched_info.last_queued; | 570 | |
| 638 | sched_info_dequeued(t); | 571 | if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) |
| 639 | t->sched_info.run_delay += delta_jiffies; | 572 | return; |
| 640 | t->sched_info.last_arrival = now; | ||
| 641 | t->sched_info.pcnt++; | ||
| 642 | 573 | ||
| 643 | rq_sched_info_arrive(task_rq(t), delta_jiffies); | 574 | set_tsk_thread_flag(p, TIF_NEED_RESCHED); |
| 575 | |||
| 576 | cpu = task_cpu(p); | ||
| 577 | if (cpu == smp_processor_id()) | ||
| 578 | return; | ||
| 579 | |||
| 580 | /* NEED_RESCHED must be visible before we test polling */ | ||
| 581 | smp_mb(); | ||
| 582 | if (!tsk_is_polling(p)) | ||
| 583 | smp_send_reschedule(cpu); | ||
| 644 | } | 584 | } |
| 645 | 585 | ||
| 646 | /* | 586 | static void resched_cpu(int cpu) |
| 647 | * Called when a process is queued into either the active or expired | ||
| 648 | * array. The time is noted and later used to determine how long we | ||
| 649 | * had to wait for us to reach the cpu. Since the expired queue will | ||
| 650 | * become the active queue after active queue is empty, without dequeuing | ||
| 651 | * and requeuing any tasks, we are interested in queuing to either. It | ||
| 652 | * is unusual but not impossible for tasks to be dequeued and immediately | ||
| 653 | * requeued in the same or another array: this can happen in sched_yield(), | ||
| 654 | * set_user_nice(), and even load_balance() as it moves tasks from runqueue | ||
| 655 | * to runqueue. | ||
| 656 | * | ||
| 657 | * This function is only called from enqueue_task(), but also only updates | ||
| 658 | * the timestamp if it is already not set. It's assumed that | ||
| 659 | * sched_info_dequeued() will clear that stamp when appropriate. | ||
| 660 | */ | ||
| 661 | static inline void sched_info_queued(struct task_struct *t) | ||
| 662 | { | 587 | { |
| 663 | if (unlikely(sched_info_on())) | 588 | struct rq *rq = cpu_rq(cpu); |
| 664 | if (!t->sched_info.last_queued) | 589 | unsigned long flags; |
| 665 | t->sched_info.last_queued = jiffies; | 590 | |
| 591 | if (!spin_trylock_irqsave(&rq->lock, flags)) | ||
| 592 | return; | ||
| 593 | resched_task(cpu_curr(cpu)); | ||
| 594 | spin_unlock_irqrestore(&rq->lock, flags); | ||
| 595 | } | ||
| 596 | #else | ||
| 597 | static inline void resched_task(struct task_struct *p) | ||
| 598 | { | ||
| 599 | assert_spin_locked(&task_rq(p)->lock); | ||
| 600 | set_tsk_need_resched(p); | ||
| 666 | } | 601 | } |
| 602 | #endif | ||
| 667 | 603 | ||
| 668 | /* | 604 | static u64 div64_likely32(u64 divident, unsigned long divisor) |
| 669 | * Called when a process ceases being the active-running process, either | ||
| 670 | * voluntarily or involuntarily. Now we can calculate how long we ran. | ||
| 671 | */ | ||
| 672 | static inline void sched_info_depart(struct task_struct *t) | ||
| 673 | { | 605 | { |
| 674 | unsigned long delta_jiffies = jiffies - t->sched_info.last_arrival; | 606 | #if BITS_PER_LONG == 32 |
| 607 | if (likely(divident <= 0xffffffffULL)) | ||
| 608 | return (u32)divident / divisor; | ||
| 609 | do_div(divident, divisor); | ||
| 675 | 610 | ||
| 676 | t->sched_info.cpu_time += delta_jiffies; | 611 | return divident; |
| 677 | rq_sched_info_depart(task_rq(t), delta_jiffies); | 612 | #else |
| 613 | return divident / divisor; | ||
| 614 | #endif | ||
| 678 | } | 615 | } |
| 679 | 616 | ||
| 680 | /* | 617 | #if BITS_PER_LONG == 32 |
| 681 | * Called when tasks are switched involuntarily due, typically, to expiring | 618 | # define WMULT_CONST (~0UL) |
| 682 | * their time slice. (This may also be called when switching to or from | 619 | #else |
| 683 | * the idle task.) We are only called when prev != next. | 620 | # define WMULT_CONST (1UL << 32) |
| 684 | */ | 621 | #endif |
| 685 | static inline void | 622 | |
| 686 | __sched_info_switch(struct task_struct *prev, struct task_struct *next) | 623 | #define WMULT_SHIFT 32 |
| 624 | |||
| 625 | static inline unsigned long | ||
| 626 | calc_delta_mine(unsigned long delta_exec, unsigned long weight, | ||
| 627 | struct load_weight *lw) | ||
| 687 | { | 628 | { |
| 688 | struct rq *rq = task_rq(prev); | 629 | u64 tmp; |
| 630 | |||
| 631 | if (unlikely(!lw->inv_weight)) | ||
| 632 | lw->inv_weight = WMULT_CONST / lw->weight; | ||
| 689 | 633 | ||
| 634 | tmp = (u64)delta_exec * weight; | ||
| 690 | /* | 635 | /* |
| 691 | * prev now departs the cpu. It's not interesting to record | 636 | * Check whether we'd overflow the 64-bit multiplication: |
| 692 | * stats about how efficient we were at scheduling the idle | ||
| 693 | * process, however. | ||
| 694 | */ | 637 | */ |
| 695 | if (prev != rq->idle) | 638 | if (unlikely(tmp > WMULT_CONST)) { |
| 696 | sched_info_depart(prev); | 639 | tmp = ((tmp >> WMULT_SHIFT/2) * lw->inv_weight) |
| 640 | >> (WMULT_SHIFT/2); | ||
| 641 | } else { | ||
| 642 | tmp = (tmp * lw->inv_weight) >> WMULT_SHIFT; | ||
| 643 | } | ||
| 697 | 644 | ||
| 698 | if (next != rq->idle) | 645 | return (unsigned long)min(tmp, (u64)sysctl_sched_runtime_limit); |
| 699 | sched_info_arrive(next); | ||
| 700 | } | 646 | } |
| 701 | static inline void | ||
| 702 | sched_info_switch(struct task_struct *prev, struct task_struct *next) | ||
| 703 | { | ||
| 704 | if (unlikely(sched_info_on())) | ||
| 705 | __sched_info_switch(prev, next); | ||
| 706 | } | ||
| 707 | #else | ||
| 708 | #define sched_info_queued(t) do { } while (0) | ||
| 709 | #define sched_info_switch(t, next) do { } while (0) | ||
| 710 | #endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */ | ||
| 711 | 647 | ||
| 712 | /* | 648 | static inline unsigned long |
| 713 | * Adding/removing a task to/from a priority array: | 649 | calc_delta_fair(unsigned long delta_exec, struct load_weight *lw) |
| 714 | */ | ||
| 715 | static void dequeue_task(struct task_struct *p, struct prio_array *array) | ||
| 716 | { | 650 | { |
| 717 | array->nr_active--; | 651 | return calc_delta_mine(delta_exec, NICE_0_LOAD, lw); |
| 718 | list_del(&p->run_list); | ||
| 719 | if (list_empty(array->queue + p->prio)) | ||
| 720 | __clear_bit(p->prio, array->bitmap); | ||
| 721 | } | 652 | } |
| 722 | 653 | ||
| 723 | static void enqueue_task(struct task_struct *p, struct prio_array *array) | 654 | static void update_load_add(struct load_weight *lw, unsigned long inc) |
| 724 | { | 655 | { |
| 725 | sched_info_queued(p); | 656 | lw->weight += inc; |
| 726 | list_add_tail(&p->run_list, array->queue + p->prio); | 657 | lw->inv_weight = 0; |
| 727 | __set_bit(p->prio, array->bitmap); | ||
| 728 | array->nr_active++; | ||
| 729 | p->array = array; | ||
| 730 | } | 658 | } |
| 731 | 659 | ||
| 732 | /* | 660 | static void update_load_sub(struct load_weight *lw, unsigned long dec) |
| 733 | * Put task to the end of the run list without the overhead of dequeue | ||
| 734 | * followed by enqueue. | ||
| 735 | */ | ||
| 736 | static void requeue_task(struct task_struct *p, struct prio_array *array) | ||
| 737 | { | 661 | { |
| 738 | list_move_tail(&p->run_list, array->queue + p->prio); | 662 | lw->weight -= dec; |
| 663 | lw->inv_weight = 0; | ||
| 739 | } | 664 | } |
| 740 | 665 | ||
| 741 | static inline void | 666 | static void __update_curr_load(struct rq *rq, struct load_stat *ls) |
| 742 | enqueue_task_head(struct task_struct *p, struct prio_array *array) | ||
| 743 | { | 667 | { |
| 744 | list_add(&p->run_list, array->queue + p->prio); | 668 | if (rq->curr != rq->idle && ls->load.weight) { |
| 745 | __set_bit(p->prio, array->bitmap); | 669 | ls->delta_exec += ls->delta_stat; |
| 746 | array->nr_active++; | 670 | ls->delta_fair += calc_delta_fair(ls->delta_stat, &ls->load); |
| 747 | p->array = array; | 671 | ls->delta_stat = 0; |
| 672 | } | ||
| 748 | } | 673 | } |
| 749 | 674 | ||
| 750 | /* | 675 | /* |
| 751 | * __normal_prio - return the priority that is based on the static | 676 | * Update delta_exec, delta_fair fields for rq. |
| 752 | * priority but is modified by bonuses/penalties. | ||
| 753 | * | ||
| 754 | * We scale the actual sleep average [0 .... MAX_SLEEP_AVG] | ||
| 755 | * into the -5 ... 0 ... +5 bonus/penalty range. | ||
| 756 | * | 677 | * |
| 757 | * We use 25% of the full 0...39 priority range so that: | 678 | * delta_fair clock advances at a rate inversely proportional to |
| 679 | * total load (rq->ls.load.weight) on the runqueue, while | ||
| 680 | * delta_exec advances at the same rate as wall-clock (provided | ||
| 681 | * cpu is not idle). | ||
| 758 | * | 682 | * |
| 759 | * 1) nice +19 interactive tasks do not preempt nice 0 CPU hogs. | 683 | * delta_exec / delta_fair is a measure of the (smoothened) load on this |
| 760 | * 2) nice -20 CPU hogs do not get preempted by nice 0 tasks. | 684 | * runqueue over any given interval. This (smoothened) load is used |
| 685 | * during load balance. | ||
| 761 | * | 686 | * |
| 762 | * Both properties are important to certain workloads. | 687 | * This function is called /before/ updating rq->ls.load |
| 688 | * and when switching tasks. | ||
| 763 | */ | 689 | */ |
| 764 | 690 | static void update_curr_load(struct rq *rq, u64 now) | |
| 765 | static inline int __normal_prio(struct task_struct *p) | ||
| 766 | { | 691 | { |
| 767 | int bonus, prio; | 692 | struct load_stat *ls = &rq->ls; |
| 693 | u64 start; | ||
| 768 | 694 | ||
| 769 | bonus = CURRENT_BONUS(p) - MAX_BONUS / 2; | 695 | start = ls->load_update_start; |
| 770 | 696 | ls->load_update_start = now; | |
| 771 | prio = p->static_prio - bonus; | 697 | ls->delta_stat += now - start; |
| 772 | if (prio < MAX_RT_PRIO) | 698 | /* |
| 773 | prio = MAX_RT_PRIO; | 699 | * Stagger updates to ls->delta_fair. Very frequent updates |
| 774 | if (prio > MAX_PRIO-1) | 700 | * can be expensive. |
| 775 | prio = MAX_PRIO-1; | 701 | */ |
| 776 | return prio; | 702 | if (ls->delta_stat >= sysctl_sched_stat_granularity) |
| 703 | __update_curr_load(rq, ls); | ||
| 777 | } | 704 | } |
| 778 | 705 | ||
| 779 | /* | 706 | /* |
| @@ -791,53 +718,146 @@ static inline int __normal_prio(struct task_struct *p) | |||
| 791 | * this code will need modification | 718 | * this code will need modification |
| 792 | */ | 719 | */ |
| 793 | #define TIME_SLICE_NICE_ZERO DEF_TIMESLICE | 720 | #define TIME_SLICE_NICE_ZERO DEF_TIMESLICE |
| 794 | #define LOAD_WEIGHT(lp) \ | 721 | #define load_weight(lp) \ |
| 795 | (((lp) * SCHED_LOAD_SCALE) / TIME_SLICE_NICE_ZERO) | 722 | (((lp) * SCHED_LOAD_SCALE) / TIME_SLICE_NICE_ZERO) |
| 796 | #define PRIO_TO_LOAD_WEIGHT(prio) \ | 723 | #define PRIO_TO_LOAD_WEIGHT(prio) \ |
| 797 | LOAD_WEIGHT(static_prio_timeslice(prio)) | 724 | load_weight(static_prio_timeslice(prio)) |
| 798 | #define RTPRIO_TO_LOAD_WEIGHT(rp) \ | 725 | #define RTPRIO_TO_LOAD_WEIGHT(rp) \ |
| 799 | (PRIO_TO_LOAD_WEIGHT(MAX_RT_PRIO) + LOAD_WEIGHT(rp)) | 726 | (PRIO_TO_LOAD_WEIGHT(MAX_RT_PRIO) + load_weight(rp)) |
| 800 | 727 | ||
| 801 | static void set_load_weight(struct task_struct *p) | 728 | #define WEIGHT_IDLEPRIO 2 |
| 802 | { | 729 | #define WMULT_IDLEPRIO (1 << 31) |
| 803 | if (has_rt_policy(p)) { | 730 | |
| 804 | #ifdef CONFIG_SMP | 731 | /* |
| 805 | if (p == task_rq(p)->migration_thread) | 732 | * Nice levels are multiplicative, with a gentle 10% change for every |
| 806 | /* | 733 | * nice level changed. I.e. when a CPU-bound task goes from nice 0 to |
| 807 | * The migration thread does the actual balancing. | 734 | * nice 1, it will get ~10% less CPU time than another CPU-bound task |
| 808 | * Giving its load any weight will skew balancing | 735 | * that remained on nice 0. |
| 809 | * adversely. | 736 | * |
| 810 | */ | 737 | * The "10% effect" is relative and cumulative: from _any_ nice level, |
| 811 | p->load_weight = 0; | 738 | * if you go up 1 level, it's -10% CPU usage, if you go down 1 level |
| 812 | else | 739 | * it's +10% CPU usage. |
| 813 | #endif | 740 | */ |
| 814 | p->load_weight = RTPRIO_TO_LOAD_WEIGHT(p->rt_priority); | 741 | static const int prio_to_weight[40] = { |
| 815 | } else | 742 | /* -20 */ 88818, 71054, 56843, 45475, 36380, 29104, 23283, 18626, 14901, 11921, |
| 816 | p->load_weight = PRIO_TO_LOAD_WEIGHT(p->static_prio); | 743 | /* -10 */ 9537, 7629, 6103, 4883, 3906, 3125, 2500, 2000, 1600, 1280, |
| 817 | } | 744 | /* 0 */ NICE_0_LOAD /* 1024 */, |
| 745 | /* 1 */ 819, 655, 524, 419, 336, 268, 215, 172, 137, | ||
| 746 | /* 10 */ 110, 87, 70, 56, 45, 36, 29, 23, 18, 15, | ||
| 747 | }; | ||
| 748 | |||
| 749 | static const u32 prio_to_wmult[40] = { | ||
| 750 | 48356, 60446, 75558, 94446, 118058, 147573, | ||
| 751 | 184467, 230589, 288233, 360285, 450347, | ||
| 752 | 562979, 703746, 879575, 1099582, 1374389, | ||
| 753 | 1717986, 2147483, 2684354, 3355443, 4194304, | ||
| 754 | 5244160, 6557201, 8196502, 10250518, 12782640, | ||
| 755 | 16025997, 19976592, 24970740, 31350126, 39045157, | ||
| 756 | 49367440, 61356675, 76695844, 95443717, 119304647, | ||
| 757 | 148102320, 186737708, 238609294, 286331153, | ||
| 758 | }; | ||
| 818 | 759 | ||
| 819 | static inline void | 760 | static inline void |
| 820 | inc_raw_weighted_load(struct rq *rq, const struct task_struct *p) | 761 | inc_load(struct rq *rq, const struct task_struct *p, u64 now) |
| 821 | { | 762 | { |
| 822 | rq->raw_weighted_load += p->load_weight; | 763 | update_curr_load(rq, now); |
| 764 | update_load_add(&rq->ls.load, p->se.load.weight); | ||
| 823 | } | 765 | } |
| 824 | 766 | ||
| 825 | static inline void | 767 | static inline void |
| 826 | dec_raw_weighted_load(struct rq *rq, const struct task_struct *p) | 768 | dec_load(struct rq *rq, const struct task_struct *p, u64 now) |
| 827 | { | 769 | { |
| 828 | rq->raw_weighted_load -= p->load_weight; | 770 | update_curr_load(rq, now); |
| 771 | update_load_sub(&rq->ls.load, p->se.load.weight); | ||
| 829 | } | 772 | } |
| 830 | 773 | ||
| 831 | static inline void inc_nr_running(struct task_struct *p, struct rq *rq) | 774 | static inline void inc_nr_running(struct task_struct *p, struct rq *rq, u64 now) |
| 832 | { | 775 | { |
| 833 | rq->nr_running++; | 776 | rq->nr_running++; |
| 834 | inc_raw_weighted_load(rq, p); | 777 | inc_load(rq, p, now); |
| 835 | } | 778 | } |
| 836 | 779 | ||
| 837 | static inline void dec_nr_running(struct task_struct *p, struct rq *rq) | 780 | static inline void dec_nr_running(struct task_struct *p, struct rq *rq, u64 now) |
| 838 | { | 781 | { |
| 839 | rq->nr_running--; | 782 | rq->nr_running--; |
| 840 | dec_raw_weighted_load(rq, p); | 783 | dec_load(rq, p, now); |
| 784 | } | ||
| 785 | |||
| 786 | static void activate_task(struct rq *rq, struct task_struct *p, int wakeup); | ||
| 787 | |||
| 788 | /* | ||
| 789 | * runqueue iterator, to support SMP load-balancing between different | ||
| 790 | * scheduling classes, without having to expose their internal data | ||
| 791 | * structures to the load-balancing proper: | ||
| 792 | */ | ||
| 793 | struct rq_iterator { | ||
| 794 | void *arg; | ||
| 795 | struct task_struct *(*start)(void *); | ||
| 796 | struct task_struct *(*next)(void *); | ||
| 797 | }; | ||
| 798 | |||
| 799 | static int balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, | ||
| 800 | unsigned long max_nr_move, unsigned long max_load_move, | ||
| 801 | struct sched_domain *sd, enum cpu_idle_type idle, | ||
| 802 | int *all_pinned, unsigned long *load_moved, | ||
| 803 | int this_best_prio, int best_prio, int best_prio_seen, | ||
| 804 | struct rq_iterator *iterator); | ||
| 805 | |||
| 806 | #include "sched_stats.h" | ||
| 807 | #include "sched_rt.c" | ||
| 808 | #include "sched_fair.c" | ||
| 809 | #include "sched_idletask.c" | ||
| 810 | #ifdef CONFIG_SCHED_DEBUG | ||
| 811 | # include "sched_debug.c" | ||
| 812 | #endif | ||
| 813 | |||
| 814 | #define sched_class_highest (&rt_sched_class) | ||
| 815 | |||
| 816 | static void set_load_weight(struct task_struct *p) | ||
| 817 | { | ||
| 818 | task_rq(p)->cfs.wait_runtime -= p->se.wait_runtime; | ||
| 819 | p->se.wait_runtime = 0; | ||
| 820 | |||
| 821 | if (task_has_rt_policy(p)) { | ||
| 822 | p->se.load.weight = prio_to_weight[0] * 2; | ||
| 823 | p->se.load.inv_weight = prio_to_wmult[0] >> 1; | ||
| 824 | return; | ||
| 825 | } | ||
| 826 | |||
| 827 | /* | ||
| 828 | * SCHED_IDLE tasks get minimal weight: | ||
| 829 | */ | ||
| 830 | if (p->policy == SCHED_IDLE) { | ||
| 831 | p->se.load.weight = WEIGHT_IDLEPRIO; | ||
| 832 | p->se.load.inv_weight = WMULT_IDLEPRIO; | ||
| 833 | return; | ||
| 834 | } | ||
| 835 | |||
| 836 | p->se.load.weight = prio_to_weight[p->static_prio - MAX_RT_PRIO]; | ||
| 837 | p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO]; | ||
| 838 | } | ||
| 839 | |||
| 840 | static void | ||
| 841 | enqueue_task(struct rq *rq, struct task_struct *p, int wakeup, u64 now) | ||
| 842 | { | ||
| 843 | sched_info_queued(p); | ||
| 844 | p->sched_class->enqueue_task(rq, p, wakeup, now); | ||
| 845 | p->se.on_rq = 1; | ||
| 846 | } | ||
| 847 | |||
| 848 | static void | ||
| 849 | dequeue_task(struct rq *rq, struct task_struct *p, int sleep, u64 now) | ||
| 850 | { | ||
| 851 | p->sched_class->dequeue_task(rq, p, sleep, now); | ||
| 852 | p->se.on_rq = 0; | ||
| 853 | } | ||
| 854 | |||
| 855 | /* | ||
| 856 | * __normal_prio - return the priority that is based on the static prio | ||
| 857 | */ | ||
| 858 | static inline int __normal_prio(struct task_struct *p) | ||
| 859 | { | ||
| 860 | return p->static_prio; | ||
| 841 | } | 861 | } |
| 842 | 862 | ||
| 843 | /* | 863 | /* |
| @@ -851,7 +871,7 @@ static inline int normal_prio(struct task_struct *p) | |||
| 851 | { | 871 | { |
| 852 | int prio; | 872 | int prio; |
| 853 | 873 | ||
| 854 | if (has_rt_policy(p)) | 874 | if (task_has_rt_policy(p)) |
| 855 | prio = MAX_RT_PRIO-1 - p->rt_priority; | 875 | prio = MAX_RT_PRIO-1 - p->rt_priority; |
| 856 | else | 876 | else |
| 857 | prio = __normal_prio(p); | 877 | prio = __normal_prio(p); |
| @@ -879,221 +899,46 @@ static int effective_prio(struct task_struct *p) | |||
| 879 | } | 899 | } |
| 880 | 900 | ||
| 881 | /* | 901 | /* |
| 882 | * __activate_task - move a task to the runqueue. | 902 | * activate_task - move a task to the runqueue. |
| 883 | */ | ||
| 884 | static void __activate_task(struct task_struct *p, struct rq *rq) | ||
| 885 | { | ||
| 886 | struct prio_array *target = rq->active; | ||
| 887 | |||
| 888 | if (batch_task(p)) | ||
| 889 | target = rq->expired; | ||
| 890 | enqueue_task(p, target); | ||
| 891 | inc_nr_running(p, rq); | ||
| 892 | } | ||
| 893 | |||
| 894 | /* | ||
| 895 | * __activate_idle_task - move idle task to the _front_ of runqueue. | ||
| 896 | */ | 903 | */ |
| 897 | static inline void __activate_idle_task(struct task_struct *p, struct rq *rq) | 904 | static void activate_task(struct rq *rq, struct task_struct *p, int wakeup) |
| 898 | { | 905 | { |
| 899 | enqueue_task_head(p, rq->active); | 906 | u64 now = rq_clock(rq); |
| 900 | inc_nr_running(p, rq); | ||
| 901 | } | ||
| 902 | 907 | ||
| 903 | /* | 908 | if (p->state == TASK_UNINTERRUPTIBLE) |
| 904 | * Recalculate p->normal_prio and p->prio after having slept, | 909 | rq->nr_uninterruptible--; |
| 905 | * updating the sleep-average too: | ||
| 906 | */ | ||
| 907 | static int recalc_task_prio(struct task_struct *p, unsigned long long now) | ||
| 908 | { | ||
| 909 | /* Caller must always ensure 'now >= p->timestamp' */ | ||
| 910 | unsigned long sleep_time = now - p->timestamp; | ||
| 911 | |||
| 912 | if (batch_task(p)) | ||
| 913 | sleep_time = 0; | ||
| 914 | |||
| 915 | if (likely(sleep_time > 0)) { | ||
| 916 | /* | ||
| 917 | * This ceiling is set to the lowest priority that would allow | ||
| 918 | * a task to be reinserted into the active array on timeslice | ||
| 919 | * completion. | ||
| 920 | */ | ||
| 921 | unsigned long ceiling = INTERACTIVE_SLEEP(p); | ||
| 922 | |||
| 923 | if (p->mm && sleep_time > ceiling && p->sleep_avg < ceiling) { | ||
| 924 | /* | ||
| 925 | * Prevents user tasks from achieving best priority | ||
| 926 | * with one single large enough sleep. | ||
| 927 | */ | ||
| 928 | p->sleep_avg = ceiling; | ||
| 929 | /* | ||
| 930 | * Using INTERACTIVE_SLEEP() as a ceiling places a | ||
| 931 | * nice(0) task 1ms sleep away from promotion, and | ||
| 932 | * gives it 700ms to round-robin with no chance of | ||
| 933 | * being demoted. This is more than generous, so | ||
| 934 | * mark this sleep as non-interactive to prevent the | ||
| 935 | * on-runqueue bonus logic from intervening should | ||
| 936 | * this task not receive cpu immediately. | ||
| 937 | */ | ||
| 938 | p->sleep_type = SLEEP_NONINTERACTIVE; | ||
| 939 | } else { | ||
| 940 | /* | ||
| 941 | * Tasks waking from uninterruptible sleep are | ||
| 942 | * limited in their sleep_avg rise as they | ||
| 943 | * are likely to be waiting on I/O | ||
| 944 | */ | ||
| 945 | if (p->sleep_type == SLEEP_NONINTERACTIVE && p->mm) { | ||
| 946 | if (p->sleep_avg >= ceiling) | ||
| 947 | sleep_time = 0; | ||
| 948 | else if (p->sleep_avg + sleep_time >= | ||
| 949 | ceiling) { | ||
| 950 | p->sleep_avg = ceiling; | ||
| 951 | sleep_time = 0; | ||
| 952 | } | ||
| 953 | } | ||
| 954 | |||
| 955 | /* | ||
| 956 | * This code gives a bonus to interactive tasks. | ||
| 957 | * | ||
| 958 | * The boost works by updating the 'average sleep time' | ||
| 959 | * value here, based on ->timestamp. The more time a | ||
| 960 | * task spends sleeping, the higher the average gets - | ||
| 961 | * and the higher the priority boost gets as well. | ||
| 962 | */ | ||
| 963 | p->sleep_avg += sleep_time; | ||
| 964 | |||
| 965 | } | ||
| 966 | if (p->sleep_avg > NS_MAX_SLEEP_AVG) | ||
| 967 | p->sleep_avg = NS_MAX_SLEEP_AVG; | ||
| 968 | } | ||
| 969 | 910 | ||
| 970 | return effective_prio(p); | 911 | enqueue_task(rq, p, wakeup, now); |
| 912 | inc_nr_running(p, rq, now); | ||
| 971 | } | 913 | } |
| 972 | 914 | ||
| 973 | /* | 915 | /* |
| 974 | * activate_task - move a task to the runqueue and do priority recalculation | 916 | * activate_idle_task - move idle task to the _front_ of runqueue. |
| 975 | * | ||
| 976 | * Update all the scheduling statistics stuff. (sleep average | ||
| 977 | * calculation, priority modifiers, etc.) | ||
| 978 | */ | 917 | */ |
| 979 | static void activate_task(struct task_struct *p, struct rq *rq, int local) | 918 | static inline void activate_idle_task(struct task_struct *p, struct rq *rq) |
| 980 | { | 919 | { |
| 981 | unsigned long long now; | 920 | u64 now = rq_clock(rq); |
| 982 | |||
| 983 | if (rt_task(p)) | ||
| 984 | goto out; | ||
| 985 | |||
| 986 | now = sched_clock(); | ||
| 987 | #ifdef CONFIG_SMP | ||
| 988 | if (!local) { | ||
| 989 | /* Compensate for drifting sched_clock */ | ||
| 990 | struct rq *this_rq = this_rq(); | ||
| 991 | now = (now - this_rq->most_recent_timestamp) | ||
| 992 | + rq->most_recent_timestamp; | ||
| 993 | } | ||
| 994 | #endif | ||
| 995 | 921 | ||
| 996 | /* | 922 | if (p->state == TASK_UNINTERRUPTIBLE) |
| 997 | * Sleep time is in units of nanosecs, so shift by 20 to get a | 923 | rq->nr_uninterruptible--; |
| 998 | * milliseconds-range estimation of the amount of time that the task | ||
| 999 | * spent sleeping: | ||
| 1000 | */ | ||
| 1001 | if (unlikely(prof_on == SLEEP_PROFILING)) { | ||
| 1002 | if (p->state == TASK_UNINTERRUPTIBLE) | ||
| 1003 | profile_hits(SLEEP_PROFILING, (void *)get_wchan(p), | ||
| 1004 | (now - p->timestamp) >> 20); | ||
| 1005 | } | ||
| 1006 | |||
| 1007 | p->prio = recalc_task_prio(p, now); | ||
| 1008 | 924 | ||
| 1009 | /* | 925 | enqueue_task(rq, p, 0, now); |
| 1010 | * This checks to make sure it's not an uninterruptible task | 926 | inc_nr_running(p, rq, now); |
| 1011 | * that is now waking up. | ||
| 1012 | */ | ||
| 1013 | if (p->sleep_type == SLEEP_NORMAL) { | ||
| 1014 | /* | ||
| 1015 | * Tasks which were woken up by interrupts (ie. hw events) | ||
| 1016 | * are most likely of interactive nature. So we give them | ||
| 1017 | * the credit of extending their sleep time to the period | ||
| 1018 | * of time they spend on the runqueue, waiting for execution | ||
| 1019 | * on a CPU, first time around: | ||
| 1020 | */ | ||
| 1021 | if (in_interrupt()) | ||
| 1022 | p->sleep_type = SLEEP_INTERRUPTED; | ||
| 1023 | else { | ||
| 1024 | /* | ||
| 1025 | * Normal first-time wakeups get a credit too for | ||
| 1026 | * on-runqueue time, but it will be weighted down: | ||
| 1027 | */ | ||
| 1028 | p->sleep_type = SLEEP_INTERACTIVE; | ||
| 1029 | } | ||
| 1030 | } | ||
| 1031 | p->timestamp = now; | ||
| 1032 | out: | ||
| 1033 | __activate_task(p, rq); | ||
| 1034 | } | 927 | } |
| 1035 | 928 | ||
| 1036 | /* | 929 | /* |
| 1037 | * deactivate_task - remove a task from the runqueue. | 930 | * deactivate_task - remove a task from the runqueue. |
| 1038 | */ | 931 | */ |
| 1039 | static void deactivate_task(struct task_struct *p, struct rq *rq) | 932 | static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep) |
| 1040 | { | 933 | { |
| 1041 | dec_nr_running(p, rq); | 934 | u64 now = rq_clock(rq); |
| 1042 | dequeue_task(p, p->array); | ||
| 1043 | p->array = NULL; | ||
| 1044 | } | ||
| 1045 | 935 | ||
| 1046 | /* | 936 | if (p->state == TASK_UNINTERRUPTIBLE) |
| 1047 | * resched_task - mark a task 'to be rescheduled now'. | 937 | rq->nr_uninterruptible++; |
| 1048 | * | ||
| 1049 | * On UP this means the setting of the need_resched flag, on SMP it | ||
| 1050 | * might also involve a cross-CPU call to trigger the scheduler on | ||
| 1051 | * the target CPU. | ||
| 1052 | */ | ||
| 1053 | #ifdef CONFIG_SMP | ||
| 1054 | |||
| 1055 | #ifndef tsk_is_polling | ||
| 1056 | #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) | ||
| 1057 | #endif | ||
| 1058 | |||
| 1059 | static void resched_task(struct task_struct *p) | ||
| 1060 | { | ||
| 1061 | int cpu; | ||
| 1062 | |||
| 1063 | assert_spin_locked(&task_rq(p)->lock); | ||
| 1064 | |||
| 1065 | if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) | ||
| 1066 | return; | ||
| 1067 | |||
| 1068 | set_tsk_thread_flag(p, TIF_NEED_RESCHED); | ||
| 1069 | |||
| 1070 | cpu = task_cpu(p); | ||
| 1071 | if (cpu == smp_processor_id()) | ||
| 1072 | return; | ||
| 1073 | |||
| 1074 | /* NEED_RESCHED must be visible before we test polling */ | ||
| 1075 | smp_mb(); | ||
| 1076 | if (!tsk_is_polling(p)) | ||
| 1077 | smp_send_reschedule(cpu); | ||
| 1078 | } | ||
| 1079 | |||
| 1080 | static void resched_cpu(int cpu) | ||
| 1081 | { | ||
| 1082 | struct rq *rq = cpu_rq(cpu); | ||
| 1083 | unsigned long flags; | ||
| 1084 | 938 | ||
| 1085 | if (!spin_trylock_irqsave(&rq->lock, flags)) | 939 | dequeue_task(rq, p, sleep, now); |
| 1086 | return; | 940 | dec_nr_running(p, rq, now); |
| 1087 | resched_task(cpu_curr(cpu)); | ||
| 1088 | spin_unlock_irqrestore(&rq->lock, flags); | ||
| 1089 | } | 941 | } |
| 1090 | #else | ||
| 1091 | static inline void resched_task(struct task_struct *p) | ||
| 1092 | { | ||
| 1093 | assert_spin_locked(&task_rq(p)->lock); | ||
| 1094 | set_tsk_need_resched(p); | ||
| 1095 | } | ||
| 1096 | #endif | ||
| 1097 | 942 | ||
| 1098 | /** | 943 | /** |
| 1099 | * task_curr - is this task currently executing on a CPU? | 944 | * task_curr - is this task currently executing on a CPU? |
| @@ -1107,10 +952,42 @@ inline int task_curr(const struct task_struct *p) | |||
| 1107 | /* Used instead of source_load when we know the type == 0 */ | 952 | /* Used instead of source_load when we know the type == 0 */ |
| 1108 | unsigned long weighted_cpuload(const int cpu) | 953 | unsigned long weighted_cpuload(const int cpu) |
| 1109 | { | 954 | { |
| 1110 | return cpu_rq(cpu)->raw_weighted_load; | 955 | return cpu_rq(cpu)->ls.load.weight; |
| 1111 | } | 956 | } |
| 1112 | 957 | ||
| 958 | static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) | ||
| 959 | { | ||
| 1113 | #ifdef CONFIG_SMP | 960 | #ifdef CONFIG_SMP |
| 961 | task_thread_info(p)->cpu = cpu; | ||
| 962 | set_task_cfs_rq(p); | ||
| 963 | #endif | ||
| 964 | } | ||
| 965 | |||
| 966 | #ifdef CONFIG_SMP | ||
| 967 | |||
| 968 | void set_task_cpu(struct task_struct *p, unsigned int new_cpu) | ||
| 969 | { | ||
| 970 | int old_cpu = task_cpu(p); | ||
| 971 | struct rq *old_rq = cpu_rq(old_cpu), *new_rq = cpu_rq(new_cpu); | ||
| 972 | u64 clock_offset, fair_clock_offset; | ||
| 973 | |||
| 974 | clock_offset = old_rq->clock - new_rq->clock; | ||
| 975 | fair_clock_offset = old_rq->cfs.fair_clock - | ||
| 976 | new_rq->cfs.fair_clock; | ||
| 977 | if (p->se.wait_start) | ||
| 978 | p->se.wait_start -= clock_offset; | ||
| 979 | if (p->se.wait_start_fair) | ||
| 980 | p->se.wait_start_fair -= fair_clock_offset; | ||
| 981 | if (p->se.sleep_start) | ||
| 982 | p->se.sleep_start -= clock_offset; | ||
| 983 | if (p->se.block_start) | ||
| 984 | p->se.block_start -= clock_offset; | ||
| 985 | if (p->se.sleep_start_fair) | ||
| 986 | p->se.sleep_start_fair -= fair_clock_offset; | ||
| 987 | |||
| 988 | __set_task_cpu(p, new_cpu); | ||
| 989 | } | ||
| 990 | |||
| 1114 | struct migration_req { | 991 | struct migration_req { |
| 1115 | struct list_head list; | 992 | struct list_head list; |
| 1116 | 993 | ||
| @@ -1133,7 +1010,7 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req) | |||
| 1133 | * If the task is not on a runqueue (and not running), then | 1010 | * If the task is not on a runqueue (and not running), then |
| 1134 | * it is sufficient to simply update the task's cpu field. | 1011 | * it is sufficient to simply update the task's cpu field. |
| 1135 | */ | 1012 | */ |
| 1136 | if (!p->array && !task_running(rq, p)) { | 1013 | if (!p->se.on_rq && !task_running(rq, p)) { |
| 1137 | set_task_cpu(p, dest_cpu); | 1014 | set_task_cpu(p, dest_cpu); |
| 1138 | return 0; | 1015 | return 0; |
| 1139 | } | 1016 | } |
| @@ -1158,22 +1035,72 @@ migrate_task(struct task_struct *p, int dest_cpu, struct migration_req *req) | |||
| 1158 | void wait_task_inactive(struct task_struct *p) | 1035 | void wait_task_inactive(struct task_struct *p) |
| 1159 | { | 1036 | { |
| 1160 | unsigned long flags; | 1037 | unsigned long flags; |
| 1038 | int running, on_rq; | ||
| 1161 | struct rq *rq; | 1039 | struct rq *rq; |
| 1162 | int preempted; | ||
| 1163 | 1040 | ||
| 1164 | repeat: | 1041 | repeat: |
| 1042 | /* | ||
| 1043 | * We do the initial early heuristics without holding | ||
| 1044 | * any task-queue locks at all. We'll only try to get | ||
| 1045 | * the runqueue lock when things look like they will | ||
| 1046 | * work out! | ||
| 1047 | */ | ||
| 1048 | rq = task_rq(p); | ||
| 1049 | |||
| 1050 | /* | ||
| 1051 | * If the task is actively running on another CPU | ||
| 1052 | * still, just relax and busy-wait without holding | ||
| 1053 | * any locks. | ||
| 1054 | * | ||
| 1055 | * NOTE! Since we don't hold any locks, it's not | ||
| 1056 | * even sure that "rq" stays as the right runqueue! | ||
| 1057 | * But we don't care, since "task_running()" will | ||
| 1058 | * return false if the runqueue has changed and p | ||
| 1059 | * is actually now running somewhere else! | ||
| 1060 | */ | ||
| 1061 | while (task_running(rq, p)) | ||
| 1062 | cpu_relax(); | ||
| 1063 | |||
| 1064 | /* | ||
| 1065 | * Ok, time to look more closely! We need the rq | ||
| 1066 | * lock now, to be *sure*. If we're wrong, we'll | ||
| 1067 | * just go back and repeat. | ||
| 1068 | */ | ||
| 1165 | rq = task_rq_lock(p, &flags); | 1069 | rq = task_rq_lock(p, &flags); |
| 1166 | /* Must be off runqueue entirely, not preempted. */ | 1070 | running = task_running(rq, p); |
| 1167 | if (unlikely(p->array || task_running(rq, p))) { | 1071 | on_rq = p->se.on_rq; |
| 1168 | /* If it's preempted, we yield. It could be a while. */ | 1072 | task_rq_unlock(rq, &flags); |
| 1169 | preempted = !task_running(rq, p); | 1073 | |
| 1170 | task_rq_unlock(rq, &flags); | 1074 | /* |
| 1075 | * Was it really running after all now that we | ||
| 1076 | * checked with the proper locks actually held? | ||
| 1077 | * | ||
| 1078 | * Oops. Go back and try again.. | ||
| 1079 | */ | ||
| 1080 | if (unlikely(running)) { | ||
| 1171 | cpu_relax(); | 1081 | cpu_relax(); |
| 1172 | if (preempted) | ||
| 1173 | yield(); | ||
| 1174 | goto repeat; | 1082 | goto repeat; |
| 1175 | } | 1083 | } |
| 1176 | task_rq_unlock(rq, &flags); | 1084 | |
| 1085 | /* | ||
| 1086 | * It's not enough that it's not actively running, | ||
| 1087 | * it must be off the runqueue _entirely_, and not | ||
| 1088 | * preempted! | ||
| 1089 | * | ||
| 1090 | * So if it wa still runnable (but just not actively | ||
| 1091 | * running right now), it's preempted, and we should | ||
| 1092 | * yield - it could be a while. | ||
| 1093 | */ | ||
| 1094 | if (unlikely(on_rq)) { | ||
| 1095 | yield(); | ||
| 1096 | goto repeat; | ||
| 1097 | } | ||
| 1098 | |||
| 1099 | /* | ||
| 1100 | * Ahh, all good. It wasn't running, and it wasn't | ||
| 1101 | * runnable, which means that it will never become | ||
| 1102 | * running in the future either. We're all done! | ||
| 1103 | */ | ||
| 1177 | } | 1104 | } |
| 1178 | 1105 | ||
| 1179 | /*** | 1106 | /*** |
| @@ -1210,11 +1137,12 @@ void kick_process(struct task_struct *p) | |||
| 1210 | static inline unsigned long source_load(int cpu, int type) | 1137 | static inline unsigned long source_load(int cpu, int type) |
| 1211 | { | 1138 | { |
| 1212 | struct rq *rq = cpu_rq(cpu); | 1139 | struct rq *rq = cpu_rq(cpu); |
| 1140 | unsigned long total = weighted_cpuload(cpu); | ||
| 1213 | 1141 | ||
| 1214 | if (type == 0) | 1142 | if (type == 0) |
| 1215 | return rq->raw_weighted_load; | 1143 | return total; |
| 1216 | 1144 | ||
| 1217 | return min(rq->cpu_load[type-1], rq->raw_weighted_load); | 1145 | return min(rq->cpu_load[type-1], total); |
| 1218 | } | 1146 | } |
| 1219 | 1147 | ||
| 1220 | /* | 1148 | /* |
| @@ -1224,11 +1152,12 @@ static inline unsigned long source_load(int cpu, int type) | |||
| 1224 | static inline unsigned long target_load(int cpu, int type) | 1152 | static inline unsigned long target_load(int cpu, int type) |
| 1225 | { | 1153 | { |
| 1226 | struct rq *rq = cpu_rq(cpu); | 1154 | struct rq *rq = cpu_rq(cpu); |
| 1155 | unsigned long total = weighted_cpuload(cpu); | ||
| 1227 | 1156 | ||
| 1228 | if (type == 0) | 1157 | if (type == 0) |
| 1229 | return rq->raw_weighted_load; | 1158 | return total; |
| 1230 | 1159 | ||
| 1231 | return max(rq->cpu_load[type-1], rq->raw_weighted_load); | 1160 | return max(rq->cpu_load[type-1], total); |
| 1232 | } | 1161 | } |
| 1233 | 1162 | ||
| 1234 | /* | 1163 | /* |
| @@ -1237,9 +1166,10 @@ static inline unsigned long target_load(int cpu, int type) | |||
| 1237 | static inline unsigned long cpu_avg_load_per_task(int cpu) | 1166 | static inline unsigned long cpu_avg_load_per_task(int cpu) |
| 1238 | { | 1167 | { |
| 1239 | struct rq *rq = cpu_rq(cpu); | 1168 | struct rq *rq = cpu_rq(cpu); |
| 1169 | unsigned long total = weighted_cpuload(cpu); | ||
| 1240 | unsigned long n = rq->nr_running; | 1170 | unsigned long n = rq->nr_running; |
| 1241 | 1171 | ||
| 1242 | return n ? rq->raw_weighted_load / n : SCHED_LOAD_SCALE; | 1172 | return n ? total / n : SCHED_LOAD_SCALE; |
| 1243 | } | 1173 | } |
| 1244 | 1174 | ||
| 1245 | /* | 1175 | /* |
| @@ -1341,9 +1271,9 @@ static int sched_balance_self(int cpu, int flag) | |||
| 1341 | struct sched_domain *tmp, *sd = NULL; | 1271 | struct sched_domain *tmp, *sd = NULL; |
| 1342 | 1272 | ||
| 1343 | for_each_domain(cpu, tmp) { | 1273 | for_each_domain(cpu, tmp) { |
| 1344 | /* | 1274 | /* |
| 1345 | * If power savings logic is enabled for a domain, stop there. | 1275 | * If power savings logic is enabled for a domain, stop there. |
| 1346 | */ | 1276 | */ |
| 1347 | if (tmp->flags & SD_POWERSAVINGS_BALANCE) | 1277 | if (tmp->flags & SD_POWERSAVINGS_BALANCE) |
| 1348 | break; | 1278 | break; |
| 1349 | if (tmp->flags & flag) | 1279 | if (tmp->flags & flag) |
| @@ -1426,9 +1356,9 @@ static int wake_idle(int cpu, struct task_struct *p) | |||
| 1426 | if (idle_cpu(i)) | 1356 | if (idle_cpu(i)) |
| 1427 | return i; | 1357 | return i; |
| 1428 | } | 1358 | } |
| 1429 | } | 1359 | } else { |
| 1430 | else | ||
| 1431 | break; | 1360 | break; |
| 1361 | } | ||
| 1432 | } | 1362 | } |
| 1433 | return cpu; | 1363 | return cpu; |
| 1434 | } | 1364 | } |
| @@ -1470,7 +1400,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync) | |||
| 1470 | if (!(old_state & state)) | 1400 | if (!(old_state & state)) |
| 1471 | goto out; | 1401 | goto out; |
| 1472 | 1402 | ||
| 1473 | if (p->array) | 1403 | if (p->se.on_rq) |
| 1474 | goto out_running; | 1404 | goto out_running; |
| 1475 | 1405 | ||
| 1476 | cpu = task_cpu(p); | 1406 | cpu = task_cpu(p); |
| @@ -1525,11 +1455,11 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync) | |||
| 1525 | * of the current CPU: | 1455 | * of the current CPU: |
| 1526 | */ | 1456 | */ |
| 1527 | if (sync) | 1457 | if (sync) |
| 1528 | tl -= current->load_weight; | 1458 | tl -= current->se.load.weight; |
| 1529 | 1459 | ||
| 1530 | if ((tl <= load && | 1460 | if ((tl <= load && |
| 1531 | tl + target_load(cpu, idx) <= tl_per_task) || | 1461 | tl + target_load(cpu, idx) <= tl_per_task) || |
| 1532 | 100*(tl + p->load_weight) <= imbalance*load) { | 1462 | 100*(tl + p->se.load.weight) <= imbalance*load) { |
| 1533 | /* | 1463 | /* |
| 1534 | * This domain has SD_WAKE_AFFINE and | 1464 | * This domain has SD_WAKE_AFFINE and |
| 1535 | * p is cache cold in this domain, and | 1465 | * p is cache cold in this domain, and |
| @@ -1563,7 +1493,7 @@ out_set_cpu: | |||
| 1563 | old_state = p->state; | 1493 | old_state = p->state; |
| 1564 | if (!(old_state & state)) | 1494 | if (!(old_state & state)) |
| 1565 | goto out; | 1495 | goto out; |
| 1566 | if (p->array) | 1496 | if (p->se.on_rq) |
| 1567 | goto out_running; | 1497 | goto out_running; |
| 1568 | 1498 | ||
| 1569 | this_cpu = smp_processor_id(); | 1499 | this_cpu = smp_processor_id(); |
| @@ -1572,25 +1502,7 @@ out_set_cpu: | |||
| 1572 | 1502 | ||
| 1573 | out_activate: | 1503 | out_activate: |
| 1574 | #endif /* CONFIG_SMP */ | 1504 | #endif /* CONFIG_SMP */ |
| 1575 | if (old_state == TASK_UNINTERRUPTIBLE) { | 1505 | activate_task(rq, p, 1); |
| 1576 | rq->nr_uninterruptible--; | ||
| 1577 | /* | ||
| 1578 | * Tasks on involuntary sleep don't earn | ||
| 1579 | * sleep_avg beyond just interactive state. | ||
| 1580 | */ | ||
| 1581 | p->sleep_type = SLEEP_NONINTERACTIVE; | ||
| 1582 | } else | ||
| 1583 | |||
| 1584 | /* | ||
| 1585 | * Tasks that have marked their sleep as noninteractive get | ||
| 1586 | * woken up with their sleep average not weighted in an | ||
| 1587 | * interactive way. | ||
| 1588 | */ | ||
| 1589 | if (old_state & TASK_NONINTERACTIVE) | ||
| 1590 | p->sleep_type = SLEEP_NONINTERACTIVE; | ||
| 1591 | |||
| 1592 | |||
| 1593 | activate_task(p, rq, cpu == this_cpu); | ||
| 1594 | /* | 1506 | /* |
| 1595 | * Sync wakeups (i.e. those types of wakeups where the waker | 1507 | * Sync wakeups (i.e. those types of wakeups where the waker |
| 1596 | * has indicated that it will leave the CPU in short order) | 1508 | * has indicated that it will leave the CPU in short order) |
| @@ -1599,10 +1511,8 @@ out_activate: | |||
| 1599 | * the waker guarantees that the freshly woken up task is going | 1511 | * the waker guarantees that the freshly woken up task is going |
| 1600 | * to be considered on this CPU.) | 1512 | * to be considered on this CPU.) |
| 1601 | */ | 1513 | */ |
| 1602 | if (!sync || cpu != this_cpu) { | 1514 | if (!sync || cpu != this_cpu) |
| 1603 | if (TASK_PREEMPTS_CURR(p, rq)) | 1515 | check_preempt_curr(rq, p); |
| 1604 | resched_task(rq->curr); | ||
| 1605 | } | ||
| 1606 | success = 1; | 1516 | success = 1; |
| 1607 | 1517 | ||
| 1608 | out_running: | 1518 | out_running: |
| @@ -1625,19 +1535,36 @@ int fastcall wake_up_state(struct task_struct *p, unsigned int state) | |||
| 1625 | return try_to_wake_up(p, state, 0); | 1535 | return try_to_wake_up(p, state, 0); |
| 1626 | } | 1536 | } |
| 1627 | 1537 | ||
| 1628 | static void task_running_tick(struct rq *rq, struct task_struct *p); | ||
| 1629 | /* | 1538 | /* |
| 1630 | * Perform scheduler related setup for a newly forked process p. | 1539 | * Perform scheduler related setup for a newly forked process p. |
| 1631 | * p is forked by current. | 1540 | * p is forked by current. |
| 1632 | */ | 1541 | * |
| 1633 | void fastcall sched_fork(struct task_struct *p, int clone_flags) | 1542 | * __sched_fork() is basic setup used by init_idle() too: |
| 1634 | { | 1543 | */ |
| 1635 | int cpu = get_cpu(); | 1544 | static void __sched_fork(struct task_struct *p) |
| 1545 | { | ||
| 1546 | p->se.wait_start_fair = 0; | ||
| 1547 | p->se.wait_start = 0; | ||
| 1548 | p->se.exec_start = 0; | ||
| 1549 | p->se.sum_exec_runtime = 0; | ||
| 1550 | p->se.delta_exec = 0; | ||
| 1551 | p->se.delta_fair_run = 0; | ||
| 1552 | p->se.delta_fair_sleep = 0; | ||
| 1553 | p->se.wait_runtime = 0; | ||
| 1554 | p->se.sum_wait_runtime = 0; | ||
| 1555 | p->se.sum_sleep_runtime = 0; | ||
| 1556 | p->se.sleep_start = 0; | ||
| 1557 | p->se.sleep_start_fair = 0; | ||
| 1558 | p->se.block_start = 0; | ||
| 1559 | p->se.sleep_max = 0; | ||
| 1560 | p->se.block_max = 0; | ||
| 1561 | p->se.exec_max = 0; | ||
| 1562 | p->se.wait_max = 0; | ||
| 1563 | p->se.wait_runtime_overruns = 0; | ||
| 1564 | p->se.wait_runtime_underruns = 0; | ||
| 1636 | 1565 | ||
| 1637 | #ifdef CONFIG_SMP | 1566 | INIT_LIST_HEAD(&p->run_list); |
| 1638 | cpu = sched_balance_self(cpu, SD_BALANCE_FORK); | 1567 | p->se.on_rq = 0; |
| 1639 | #endif | ||
| 1640 | set_task_cpu(p, cpu); | ||
| 1641 | 1568 | ||
| 1642 | /* | 1569 | /* |
| 1643 | * We mark the process as running here, but have not actually | 1570 | * We mark the process as running here, but have not actually |
| @@ -1646,16 +1573,29 @@ void fastcall sched_fork(struct task_struct *p, int clone_flags) | |||
| 1646 | * event cannot wake it up and insert it on the runqueue either. | 1573 | * event cannot wake it up and insert it on the runqueue either. |
| 1647 | */ | 1574 | */ |
| 1648 | p->state = TASK_RUNNING; | 1575 | p->state = TASK_RUNNING; |
| 1576 | } | ||
| 1577 | |||
| 1578 | /* | ||
| 1579 | * fork()/clone()-time setup: | ||
| 1580 | */ | ||
| 1581 | void sched_fork(struct task_struct *p, int clone_flags) | ||
| 1582 | { | ||
| 1583 | int cpu = get_cpu(); | ||
| 1584 | |||
| 1585 | __sched_fork(p); | ||
| 1586 | |||
| 1587 | #ifdef CONFIG_SMP | ||
| 1588 | cpu = sched_balance_self(cpu, SD_BALANCE_FORK); | ||
| 1589 | #endif | ||
| 1590 | __set_task_cpu(p, cpu); | ||
| 1649 | 1591 | ||
| 1650 | /* | 1592 | /* |
| 1651 | * Make sure we do not leak PI boosting priority to the child: | 1593 | * Make sure we do not leak PI boosting priority to the child: |
| 1652 | */ | 1594 | */ |
| 1653 | p->prio = current->normal_prio; | 1595 | p->prio = current->normal_prio; |
| 1654 | 1596 | ||
| 1655 | INIT_LIST_HEAD(&p->run_list); | ||
| 1656 | p->array = NULL; | ||
| 1657 | #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) | 1597 | #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) |
| 1658 | if (unlikely(sched_info_on())) | 1598 | if (likely(sched_info_on())) |
| 1659 | memset(&p->sched_info, 0, sizeof(p->sched_info)); | 1599 | memset(&p->sched_info, 0, sizeof(p->sched_info)); |
| 1660 | #endif | 1600 | #endif |
| 1661 | #if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) | 1601 | #if defined(CONFIG_SMP) && defined(__ARCH_WANT_UNLOCKED_CTXSW) |
| @@ -1665,34 +1605,16 @@ void fastcall sched_fork(struct task_struct *p, int clone_flags) | |||
| 1665 | /* Want to start with kernel preemption disabled. */ | 1605 | /* Want to start with kernel preemption disabled. */ |
| 1666 | task_thread_info(p)->preempt_count = 1; | 1606 | task_thread_info(p)->preempt_count = 1; |
| 1667 | #endif | 1607 | #endif |
| 1668 | /* | ||
| 1669 | * Share the timeslice between parent and child, thus the | ||
| 1670 | * total amount of pending timeslices in the system doesn't change, | ||
| 1671 | * resulting in more scheduling fairness. | ||
| 1672 | */ | ||
| 1673 | local_irq_disable(); | ||
| 1674 | p->time_slice = (current->time_slice + 1) >> 1; | ||
| 1675 | /* | ||
| 1676 | * The remainder of the first timeslice might be recovered by | ||
| 1677 | * the parent if the child exits early enough. | ||
| 1678 | */ | ||
| 1679 | p->first_time_slice = 1; | ||
| 1680 | current->time_slice >>= 1; | ||
| 1681 | p->timestamp = sched_clock(); | ||
| 1682 | if (unlikely(!current->time_slice)) { | ||
| 1683 | /* | ||
| 1684 | * This case is rare, it happens when the parent has only | ||
| 1685 | * a single jiffy left from its timeslice. Taking the | ||
| 1686 | * runqueue lock is not a problem. | ||
| 1687 | */ | ||
| 1688 | current->time_slice = 1; | ||
| 1689 | task_running_tick(cpu_rq(cpu), current); | ||
| 1690 | } | ||
| 1691 | local_irq_enable(); | ||
| 1692 | put_cpu(); | 1608 | put_cpu(); |
| 1693 | } | 1609 | } |
| 1694 | 1610 | ||
| 1695 | /* | 1611 | /* |
| 1612 | * After fork, child runs first. (default) If set to 0 then | ||
| 1613 | * parent will (try to) run first. | ||
| 1614 | */ | ||
| 1615 | unsigned int __read_mostly sysctl_sched_child_runs_first = 1; | ||
| 1616 | |||
| 1617 | /* | ||
| 1696 | * wake_up_new_task - wake up a newly created task for the first time. | 1618 | * wake_up_new_task - wake up a newly created task for the first time. |
| 1697 | * | 1619 | * |
| 1698 | * This function will do some initial scheduler statistics housekeeping | 1620 | * This function will do some initial scheduler statistics housekeeping |
| @@ -1701,107 +1623,27 @@ void fastcall sched_fork(struct task_struct *p, int clone_flags) | |||
| 1701 | */ | 1623 | */ |
| 1702 | void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags) | 1624 | void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags) |
| 1703 | { | 1625 | { |
| 1704 | struct rq *rq, *this_rq; | ||
| 1705 | unsigned long flags; | 1626 | unsigned long flags; |
| 1706 | int this_cpu, cpu; | 1627 | struct rq *rq; |
| 1628 | int this_cpu; | ||
| 1707 | 1629 | ||
| 1708 | rq = task_rq_lock(p, &flags); | 1630 | rq = task_rq_lock(p, &flags); |
| 1709 | BUG_ON(p->state != TASK_RUNNING); | 1631 | BUG_ON(p->state != TASK_RUNNING); |
| 1710 | this_cpu = smp_processor_id(); | 1632 | this_cpu = smp_processor_id(); /* parent's CPU */ |
| 1711 | cpu = task_cpu(p); | ||
| 1712 | |||
| 1713 | /* | ||
| 1714 | * We decrease the sleep average of forking parents | ||
| 1715 | * and children as well, to keep max-interactive tasks | ||
| 1716 | * from forking tasks that are max-interactive. The parent | ||
| 1717 | * (current) is done further down, under its lock. | ||
| 1718 | */ | ||
| 1719 | p->sleep_avg = JIFFIES_TO_NS(CURRENT_BONUS(p) * | ||
| 1720 | CHILD_PENALTY / 100 * MAX_SLEEP_AVG / MAX_BONUS); | ||
| 1721 | 1633 | ||
| 1722 | p->prio = effective_prio(p); | 1634 | p->prio = effective_prio(p); |
| 1723 | 1635 | ||
| 1724 | if (likely(cpu == this_cpu)) { | 1636 | if (!sysctl_sched_child_runs_first || (clone_flags & CLONE_VM) || |
| 1725 | if (!(clone_flags & CLONE_VM)) { | 1637 | task_cpu(p) != this_cpu || !current->se.on_rq) { |
| 1726 | /* | 1638 | activate_task(rq, p, 0); |
| 1727 | * The VM isn't cloned, so we're in a good position to | ||
| 1728 | * do child-runs-first in anticipation of an exec. This | ||
| 1729 | * usually avoids a lot of COW overhead. | ||
| 1730 | */ | ||
| 1731 | if (unlikely(!current->array)) | ||
| 1732 | __activate_task(p, rq); | ||
| 1733 | else { | ||
| 1734 | p->prio = current->prio; | ||
| 1735 | p->normal_prio = current->normal_prio; | ||
| 1736 | list_add_tail(&p->run_list, ¤t->run_list); | ||
| 1737 | p->array = current->array; | ||
| 1738 | p->array->nr_active++; | ||
| 1739 | inc_nr_running(p, rq); | ||
| 1740 | } | ||
| 1741 | set_need_resched(); | ||
| 1742 | } else | ||
| 1743 | /* Run child last */ | ||
| 1744 | __activate_task(p, rq); | ||
| 1745 | /* | ||
| 1746 | * We skip the following code due to cpu == this_cpu | ||
| 1747 | * | ||
| 1748 | * task_rq_unlock(rq, &flags); | ||
| 1749 | * this_rq = task_rq_lock(current, &flags); | ||
| 1750 | */ | ||
| 1751 | this_rq = rq; | ||
| 1752 | } else { | 1639 | } else { |
| 1753 | this_rq = cpu_rq(this_cpu); | ||
| 1754 | |||
| 1755 | /* | 1640 | /* |
| 1756 | * Not the local CPU - must adjust timestamp. This should | 1641 | * Let the scheduling class do new task startup |
| 1757 | * get optimised away in the !CONFIG_SMP case. | 1642 | * management (if any): |
| 1758 | */ | 1643 | */ |
| 1759 | p->timestamp = (p->timestamp - this_rq->most_recent_timestamp) | 1644 | p->sched_class->task_new(rq, p); |
| 1760 | + rq->most_recent_timestamp; | ||
| 1761 | __activate_task(p, rq); | ||
| 1762 | if (TASK_PREEMPTS_CURR(p, rq)) | ||
| 1763 | resched_task(rq->curr); | ||
| 1764 | |||
| 1765 | /* | ||
| 1766 | * Parent and child are on different CPUs, now get the | ||
| 1767 | * parent runqueue to update the parent's ->sleep_avg: | ||
| 1768 | */ | ||
| 1769 | task_rq_unlock(rq, &flags); | ||
| 1770 | this_rq = task_rq_lock(current, &flags); | ||
| 1771 | } | ||
| 1772 | current->sleep_avg = JIFFIES_TO_NS(CURRENT_BONUS(current) * | ||
| 1773 | PARENT_PENALTY / 100 * MAX_SLEEP_AVG / MAX_BONUS); | ||
| 1774 | task_rq_unlock(this_rq, &flags); | ||
| 1775 | } | ||
| 1776 | |||
| 1777 | /* | ||
| 1778 | * Potentially available exiting-child timeslices are | ||
| 1779 | * retrieved here - this way the parent does not get | ||
| 1780 | * penalized for creating too many threads. | ||
| 1781 | * | ||
| 1782 | * (this cannot be used to 'generate' timeslices | ||
| 1783 | * artificially, because any timeslice recovered here | ||
| 1784 | * was given away by the parent in the first place.) | ||
| 1785 | */ | ||
| 1786 | void fastcall sched_exit(struct task_struct *p) | ||
| 1787 | { | ||
| 1788 | unsigned long flags; | ||
| 1789 | struct rq *rq; | ||
| 1790 | |||
| 1791 | /* | ||
| 1792 | * If the child was a (relative-) CPU hog then decrease | ||
| 1793 | * the sleep_avg of the parent as well. | ||
| 1794 | */ | ||
| 1795 | rq = task_rq_lock(p->parent, &flags); | ||
| 1796 | if (p->first_time_slice && task_cpu(p) == task_cpu(p->parent)) { | ||
| 1797 | p->parent->time_slice += p->time_slice; | ||
| 1798 | if (unlikely(p->parent->time_slice > task_timeslice(p))) | ||
| 1799 | p->parent->time_slice = task_timeslice(p); | ||
| 1800 | } | 1645 | } |
| 1801 | if (p->sleep_avg < p->parent->sleep_avg) | 1646 | check_preempt_curr(rq, p); |
| 1802 | p->parent->sleep_avg = p->parent->sleep_avg / | ||
| 1803 | (EXIT_WEIGHT + 1) * EXIT_WEIGHT + p->sleep_avg / | ||
| 1804 | (EXIT_WEIGHT + 1); | ||
| 1805 | task_rq_unlock(rq, &flags); | 1647 | task_rq_unlock(rq, &flags); |
| 1806 | } | 1648 | } |
| 1807 | 1649 | ||
| @@ -1866,7 +1708,7 @@ static inline void finish_task_switch(struct rq *rq, struct task_struct *prev) | |||
| 1866 | /* | 1708 | /* |
| 1867 | * Remove function-return probe instances associated with this | 1709 | * Remove function-return probe instances associated with this |
| 1868 | * task and put them back on the free list. | 1710 | * task and put them back on the free list. |
| 1869 | */ | 1711 | */ |
| 1870 | kprobe_flush_task(prev); | 1712 | kprobe_flush_task(prev); |
| 1871 | put_task_struct(prev); | 1713 | put_task_struct(prev); |
| 1872 | } | 1714 | } |
| @@ -1894,13 +1736,15 @@ asmlinkage void schedule_tail(struct task_struct *prev) | |||
| 1894 | * context_switch - switch to the new MM and the new | 1736 | * context_switch - switch to the new MM and the new |
| 1895 | * thread's register state. | 1737 | * thread's register state. |
| 1896 | */ | 1738 | */ |
| 1897 | static inline struct task_struct * | 1739 | static inline void |
| 1898 | context_switch(struct rq *rq, struct task_struct *prev, | 1740 | context_switch(struct rq *rq, struct task_struct *prev, |
| 1899 | struct task_struct *next) | 1741 | struct task_struct *next) |
| 1900 | { | 1742 | { |
| 1901 | struct mm_struct *mm = next->mm; | 1743 | struct mm_struct *mm, *oldmm; |
| 1902 | struct mm_struct *oldmm = prev->active_mm; | ||
| 1903 | 1744 | ||
| 1745 | prepare_task_switch(rq, next); | ||
| 1746 | mm = next->mm; | ||
| 1747 | oldmm = prev->active_mm; | ||
| 1904 | /* | 1748 | /* |
| 1905 | * For paravirt, this is coupled with an exit in switch_to to | 1749 | * For paravirt, this is coupled with an exit in switch_to to |
| 1906 | * combine the page table reload and the switch backend into | 1750 | * combine the page table reload and the switch backend into |
| @@ -1908,16 +1752,15 @@ context_switch(struct rq *rq, struct task_struct *prev, | |||
| 1908 | */ | 1752 | */ |
| 1909 | arch_enter_lazy_cpu_mode(); | 1753 | arch_enter_lazy_cpu_mode(); |
| 1910 | 1754 | ||
| 1911 | if (!mm) { | 1755 | if (unlikely(!mm)) { |
| 1912 | next->active_mm = oldmm; | 1756 | next->active_mm = oldmm; |
| 1913 | atomic_inc(&oldmm->mm_count); | 1757 | atomic_inc(&oldmm->mm_count); |
| 1914 | enter_lazy_tlb(oldmm, next); | 1758 | enter_lazy_tlb(oldmm, next); |
| 1915 | } else | 1759 | } else |
| 1916 | switch_mm(oldmm, mm, next); | 1760 | switch_mm(oldmm, mm, next); |
| 1917 | 1761 | ||
| 1918 | if (!prev->mm) { | 1762 | if (unlikely(!prev->mm)) { |
| 1919 | prev->active_mm = NULL; | 1763 | prev->active_mm = NULL; |
| 1920 | WARN_ON(rq->prev_mm); | ||
| 1921 | rq->prev_mm = oldmm; | 1764 | rq->prev_mm = oldmm; |
| 1922 | } | 1765 | } |
| 1923 | /* | 1766 | /* |
| @@ -1933,7 +1776,13 @@ context_switch(struct rq *rq, struct task_struct *prev, | |||
| 1933 | /* Here we just switch the register state and the stack. */ | 1776 | /* Here we just switch the register state and the stack. */ |
| 1934 | switch_to(prev, next, prev); | 1777 | switch_to(prev, next, prev); |
| 1935 | 1778 | ||
| 1936 | return prev; | 1779 | barrier(); |
| 1780 | /* | ||
| 1781 | * this_rq must be evaluated again because prev may have moved | ||
| 1782 | * CPUs since it called schedule(), thus the 'rq' on its stack | ||
| 1783 | * frame will be invalid. | ||
| 1784 | */ | ||
| 1785 | finish_task_switch(this_rq(), prev); | ||
| 1937 | } | 1786 | } |
| 1938 | 1787 | ||
| 1939 | /* | 1788 | /* |
| @@ -2006,17 +1855,65 @@ unsigned long nr_active(void) | |||
| 2006 | return running + uninterruptible; | 1855 | return running + uninterruptible; |
| 2007 | } | 1856 | } |
| 2008 | 1857 | ||
| 2009 | #ifdef CONFIG_SMP | ||
| 2010 | |||
| 2011 | /* | 1858 | /* |
| 2012 | * Is this task likely cache-hot: | 1859 | * Update rq->cpu_load[] statistics. This function is usually called every |
| 1860 | * scheduler tick (TICK_NSEC). | ||
| 2013 | */ | 1861 | */ |
| 2014 | static inline int | 1862 | static void update_cpu_load(struct rq *this_rq) |
| 2015 | task_hot(struct task_struct *p, unsigned long long now, struct sched_domain *sd) | ||
| 2016 | { | 1863 | { |
| 2017 | return (long long)(now - p->last_ran) < (long long)sd->cache_hot_time; | 1864 | u64 fair_delta64, exec_delta64, idle_delta64, sample_interval64, tmp64; |
| 1865 | unsigned long total_load = this_rq->ls.load.weight; | ||
| 1866 | unsigned long this_load = total_load; | ||
| 1867 | struct load_stat *ls = &this_rq->ls; | ||
| 1868 | u64 now = __rq_clock(this_rq); | ||
| 1869 | int i, scale; | ||
| 1870 | |||
| 1871 | this_rq->nr_load_updates++; | ||
| 1872 | if (unlikely(!(sysctl_sched_features & SCHED_FEAT_PRECISE_CPU_LOAD))) | ||
| 1873 | goto do_avg; | ||
| 1874 | |||
| 1875 | /* Update delta_fair/delta_exec fields first */ | ||
| 1876 | update_curr_load(this_rq, now); | ||
| 1877 | |||
| 1878 | fair_delta64 = ls->delta_fair + 1; | ||
| 1879 | ls->delta_fair = 0; | ||
| 1880 | |||
| 1881 | exec_delta64 = ls->delta_exec + 1; | ||
| 1882 | ls->delta_exec = 0; | ||
| 1883 | |||
| 1884 | sample_interval64 = now - ls->load_update_last; | ||
| 1885 | ls->load_update_last = now; | ||
| 1886 | |||
| 1887 | if ((s64)sample_interval64 < (s64)TICK_NSEC) | ||
| 1888 | sample_interval64 = TICK_NSEC; | ||
| 1889 | |||
| 1890 | if (exec_delta64 > sample_interval64) | ||
| 1891 | exec_delta64 = sample_interval64; | ||
| 1892 | |||
| 1893 | idle_delta64 = sample_interval64 - exec_delta64; | ||
| 1894 | |||
| 1895 | tmp64 = div64_64(SCHED_LOAD_SCALE * exec_delta64, fair_delta64); | ||
| 1896 | tmp64 = div64_64(tmp64 * exec_delta64, sample_interval64); | ||
| 1897 | |||
| 1898 | this_load = (unsigned long)tmp64; | ||
| 1899 | |||
| 1900 | do_avg: | ||
| 1901 | |||
| 1902 | /* Update our load: */ | ||
| 1903 | for (i = 0, scale = 1; i < CPU_LOAD_IDX_MAX; i++, scale += scale) { | ||
| 1904 | unsigned long old_load, new_load; | ||
| 1905 | |||
| 1906 | /* scale is effectively 1 << i now, and >> i divides by scale */ | ||
| 1907 | |||
| 1908 | old_load = this_rq->cpu_load[i]; | ||
| 1909 | new_load = this_load; | ||
| 1910 | |||
| 1911 | this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i; | ||
| 1912 | } | ||
| 2018 | } | 1913 | } |
| 2019 | 1914 | ||
| 1915 | #ifdef CONFIG_SMP | ||
| 1916 | |||
| 2020 | /* | 1917 | /* |
| 2021 | * double_rq_lock - safely lock two runqueues | 1918 | * double_rq_lock - safely lock two runqueues |
| 2022 | * | 1919 | * |
| @@ -2133,23 +2030,17 @@ void sched_exec(void) | |||
| 2133 | * pull_task - move a task from a remote runqueue to the local runqueue. | 2030 | * pull_task - move a task from a remote runqueue to the local runqueue. |
| 2134 | * Both runqueues must be locked. | 2031 | * Both runqueues must be locked. |
| 2135 | */ | 2032 | */ |
| 2136 | static void pull_task(struct rq *src_rq, struct prio_array *src_array, | 2033 | static void pull_task(struct rq *src_rq, struct task_struct *p, |
| 2137 | struct task_struct *p, struct rq *this_rq, | 2034 | struct rq *this_rq, int this_cpu) |
| 2138 | struct prio_array *this_array, int this_cpu) | ||
| 2139 | { | 2035 | { |
| 2140 | dequeue_task(p, src_array); | 2036 | deactivate_task(src_rq, p, 0); |
| 2141 | dec_nr_running(p, src_rq); | ||
| 2142 | set_task_cpu(p, this_cpu); | 2037 | set_task_cpu(p, this_cpu); |
| 2143 | inc_nr_running(p, this_rq); | 2038 | activate_task(this_rq, p, 0); |
| 2144 | enqueue_task(p, this_array); | ||
| 2145 | p->timestamp = (p->timestamp - src_rq->most_recent_timestamp) | ||
| 2146 | + this_rq->most_recent_timestamp; | ||
| 2147 | /* | 2039 | /* |
| 2148 | * Note that idle threads have a prio of MAX_PRIO, for this test | 2040 | * Note that idle threads have a prio of MAX_PRIO, for this test |
| 2149 | * to be always true for them. | 2041 | * to be always true for them. |
| 2150 | */ | 2042 | */ |
| 2151 | if (TASK_PREEMPTS_CURR(p, this_rq)) | 2043 | check_preempt_curr(this_rq, p); |
| 2152 | resched_task(this_rq->curr); | ||
| 2153 | } | 2044 | } |
| 2154 | 2045 | ||
| 2155 | /* | 2046 | /* |
| @@ -2157,7 +2048,7 @@ static void pull_task(struct rq *src_rq, struct prio_array *src_array, | |||
| 2157 | */ | 2048 | */ |
| 2158 | static | 2049 | static |
| 2159 | int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu, | 2050 | int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu, |
| 2160 | struct sched_domain *sd, enum idle_type idle, | 2051 | struct sched_domain *sd, enum cpu_idle_type idle, |
| 2161 | int *all_pinned) | 2052 | int *all_pinned) |
| 2162 | { | 2053 | { |
| 2163 | /* | 2054 | /* |
| @@ -2174,132 +2065,67 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu, | |||
| 2174 | return 0; | 2065 | return 0; |
| 2175 | 2066 | ||
| 2176 | /* | 2067 | /* |
| 2177 | * Aggressive migration if: | 2068 | * Aggressive migration if too many balance attempts have failed: |
| 2178 | * 1) task is cache cold, or | ||
| 2179 | * 2) too many balance attempts have failed. | ||
| 2180 | */ | 2069 | */ |
| 2181 | 2070 | if (sd->nr_balance_failed > sd->cache_nice_tries) | |
| 2182 | if (sd->nr_balance_failed > sd->cache_nice_tries) { | ||
| 2183 | #ifdef CONFIG_SCHEDSTATS | ||
| 2184 | if (task_hot(p, rq->most_recent_timestamp, sd)) | ||
| 2185 | schedstat_inc(sd, lb_hot_gained[idle]); | ||
| 2186 | #endif | ||
| 2187 | return 1; | 2071 | return 1; |
| 2188 | } | ||
| 2189 | 2072 | ||
| 2190 | if (task_hot(p, rq->most_recent_timestamp, sd)) | ||
| 2191 | return 0; | ||
| 2192 | return 1; | 2073 | return 1; |
| 2193 | } | 2074 | } |
| 2194 | 2075 | ||
| 2195 | #define rq_best_prio(rq) min((rq)->curr->prio, (rq)->best_expired_prio) | 2076 | static int balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, |
| 2196 | |||
| 2197 | /* | ||
| 2198 | * move_tasks tries to move up to max_nr_move tasks and max_load_move weighted | ||
| 2199 | * load from busiest to this_rq, as part of a balancing operation within | ||
| 2200 | * "domain". Returns the number of tasks moved. | ||
| 2201 | * | ||
| 2202 | * Called with both runqueues locked. | ||
| 2203 | */ | ||
| 2204 | static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, | ||
| 2205 | unsigned long max_nr_move, unsigned long max_load_move, | 2077 | unsigned long max_nr_move, unsigned long max_load_move, |
| 2206 | struct sched_domain *sd, enum idle_type idle, | 2078 | struct sched_domain *sd, enum cpu_idle_type idle, |
| 2207 | int *all_pinned) | 2079 | int *all_pinned, unsigned long *load_moved, |
| 2080 | int this_best_prio, int best_prio, int best_prio_seen, | ||
| 2081 | struct rq_iterator *iterator) | ||
| 2208 | { | 2082 | { |
| 2209 | int idx, pulled = 0, pinned = 0, this_best_prio, best_prio, | 2083 | int pulled = 0, pinned = 0, skip_for_load; |
| 2210 | best_prio_seen, skip_for_load; | 2084 | struct task_struct *p; |
| 2211 | struct prio_array *array, *dst_array; | 2085 | long rem_load_move = max_load_move; |
| 2212 | struct list_head *head, *curr; | ||
| 2213 | struct task_struct *tmp; | ||
| 2214 | long rem_load_move; | ||
| 2215 | 2086 | ||
| 2216 | if (max_nr_move == 0 || max_load_move == 0) | 2087 | if (max_nr_move == 0 || max_load_move == 0) |
| 2217 | goto out; | 2088 | goto out; |
| 2218 | 2089 | ||
| 2219 | rem_load_move = max_load_move; | ||
| 2220 | pinned = 1; | 2090 | pinned = 1; |
| 2221 | this_best_prio = rq_best_prio(this_rq); | ||
| 2222 | best_prio = rq_best_prio(busiest); | ||
| 2223 | /* | ||
| 2224 | * Enable handling of the case where there is more than one task | ||
| 2225 | * with the best priority. If the current running task is one | ||
| 2226 | * of those with prio==best_prio we know it won't be moved | ||
| 2227 | * and therefore it's safe to override the skip (based on load) of | ||
| 2228 | * any task we find with that prio. | ||
| 2229 | */ | ||
| 2230 | best_prio_seen = best_prio == busiest->curr->prio; | ||
| 2231 | 2091 | ||
| 2232 | /* | 2092 | /* |
| 2233 | * We first consider expired tasks. Those will likely not be | 2093 | * Start the load-balancing iterator: |
| 2234 | * executed in the near future, and they are most likely to | ||
| 2235 | * be cache-cold, thus switching CPUs has the least effect | ||
| 2236 | * on them. | ||
| 2237 | */ | 2094 | */ |
| 2238 | if (busiest->expired->nr_active) { | 2095 | p = iterator->start(iterator->arg); |
| 2239 | array = busiest->expired; | 2096 | next: |
| 2240 | dst_array = this_rq->expired; | 2097 | if (!p) |
| 2241 | } else { | ||
| 2242 | array = busiest->active; | ||
| 2243 | dst_array = this_rq->active; | ||
| 2244 | } | ||
| 2245 | |||
| 2246 | new_array: | ||
| 2247 | /* Start searching at priority 0: */ | ||
| 2248 | idx = 0; | ||
| 2249 | skip_bitmap: | ||
| 2250 | if (!idx) | ||
| 2251 | idx = sched_find_first_bit(array->bitmap); | ||
| 2252 | else | ||
| 2253 | idx = find_next_bit(array->bitmap, MAX_PRIO, idx); | ||
| 2254 | if (idx >= MAX_PRIO) { | ||
| 2255 | if (array == busiest->expired && busiest->active->nr_active) { | ||
| 2256 | array = busiest->active; | ||
| 2257 | dst_array = this_rq->active; | ||
| 2258 | goto new_array; | ||
| 2259 | } | ||
| 2260 | goto out; | 2098 | goto out; |
| 2261 | } | ||
| 2262 | |||
| 2263 | head = array->queue + idx; | ||
| 2264 | curr = head->prev; | ||
| 2265 | skip_queue: | ||
| 2266 | tmp = list_entry(curr, struct task_struct, run_list); | ||
| 2267 | |||
| 2268 | curr = curr->prev; | ||
| 2269 | |||
| 2270 | /* | 2099 | /* |
| 2271 | * To help distribute high priority tasks accross CPUs we don't | 2100 | * To help distribute high priority tasks accross CPUs we don't |
| 2272 | * skip a task if it will be the highest priority task (i.e. smallest | 2101 | * skip a task if it will be the highest priority task (i.e. smallest |
| 2273 | * prio value) on its new queue regardless of its load weight | 2102 | * prio value) on its new queue regardless of its load weight |
| 2274 | */ | 2103 | */ |
| 2275 | skip_for_load = tmp->load_weight > rem_load_move; | 2104 | skip_for_load = (p->se.load.weight >> 1) > rem_load_move + |
| 2276 | if (skip_for_load && idx < this_best_prio) | 2105 | SCHED_LOAD_SCALE_FUZZ; |
| 2277 | skip_for_load = !best_prio_seen && idx == best_prio; | 2106 | if (skip_for_load && p->prio < this_best_prio) |
| 2107 | skip_for_load = !best_prio_seen && p->prio == best_prio; | ||
| 2278 | if (skip_for_load || | 2108 | if (skip_for_load || |
| 2279 | !can_migrate_task(tmp, busiest, this_cpu, sd, idle, &pinned)) { | 2109 | !can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) { |
| 2280 | 2110 | ||
| 2281 | best_prio_seen |= idx == best_prio; | 2111 | best_prio_seen |= p->prio == best_prio; |
| 2282 | if (curr != head) | 2112 | p = iterator->next(iterator->arg); |
| 2283 | goto skip_queue; | 2113 | goto next; |
| 2284 | idx++; | ||
| 2285 | goto skip_bitmap; | ||
| 2286 | } | 2114 | } |
| 2287 | 2115 | ||
| 2288 | pull_task(busiest, array, tmp, this_rq, dst_array, this_cpu); | 2116 | pull_task(busiest, p, this_rq, this_cpu); |
| 2289 | pulled++; | 2117 | pulled++; |
| 2290 | rem_load_move -= tmp->load_weight; | 2118 | rem_load_move -= p->se.load.weight; |
| 2291 | 2119 | ||
| 2292 | /* | 2120 | /* |
| 2293 | * We only want to steal up to the prescribed number of tasks | 2121 | * We only want to steal up to the prescribed number of tasks |
| 2294 | * and the prescribed amount of weighted load. | 2122 | * and the prescribed amount of weighted load. |
| 2295 | */ | 2123 | */ |
| 2296 | if (pulled < max_nr_move && rem_load_move > 0) { | 2124 | if (pulled < max_nr_move && rem_load_move > 0) { |
| 2297 | if (idx < this_best_prio) | 2125 | if (p->prio < this_best_prio) |
| 2298 | this_best_prio = idx; | 2126 | this_best_prio = p->prio; |
| 2299 | if (curr != head) | 2127 | p = iterator->next(iterator->arg); |
| 2300 | goto skip_queue; | 2128 | goto next; |
| 2301 | idx++; | ||
| 2302 | goto skip_bitmap; | ||
| 2303 | } | 2129 | } |
| 2304 | out: | 2130 | out: |
| 2305 | /* | 2131 | /* |
| @@ -2311,18 +2137,48 @@ out: | |||
| 2311 | 2137 | ||
| 2312 | if (all_pinned) | 2138 | if (all_pinned) |
| 2313 | *all_pinned = pinned; | 2139 | *all_pinned = pinned; |
| 2140 | *load_moved = max_load_move - rem_load_move; | ||
| 2314 | return pulled; | 2141 | return pulled; |
| 2315 | } | 2142 | } |
| 2316 | 2143 | ||
| 2317 | /* | 2144 | /* |
| 2145 | * move_tasks tries to move up to max_nr_move tasks and max_load_move weighted | ||
| 2146 | * load from busiest to this_rq, as part of a balancing operation within | ||
| 2147 | * "domain". Returns the number of tasks moved. | ||
| 2148 | * | ||
| 2149 | * Called with both runqueues locked. | ||
| 2150 | */ | ||
| 2151 | static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, | ||
| 2152 | unsigned long max_nr_move, unsigned long max_load_move, | ||
| 2153 | struct sched_domain *sd, enum cpu_idle_type idle, | ||
| 2154 | int *all_pinned) | ||
| 2155 | { | ||
| 2156 | struct sched_class *class = sched_class_highest; | ||
| 2157 | unsigned long load_moved, total_nr_moved = 0, nr_moved; | ||
| 2158 | long rem_load_move = max_load_move; | ||
| 2159 | |||
| 2160 | do { | ||
| 2161 | nr_moved = class->load_balance(this_rq, this_cpu, busiest, | ||
| 2162 | max_nr_move, (unsigned long)rem_load_move, | ||
| 2163 | sd, idle, all_pinned, &load_moved); | ||
| 2164 | total_nr_moved += nr_moved; | ||
| 2165 | max_nr_move -= nr_moved; | ||
| 2166 | rem_load_move -= load_moved; | ||
| 2167 | class = class->next; | ||
| 2168 | } while (class && max_nr_move && rem_load_move > 0); | ||
| 2169 | |||
| 2170 | return total_nr_moved; | ||
| 2171 | } | ||
| 2172 | |||
| 2173 | /* | ||
| 2318 | * find_busiest_group finds and returns the busiest CPU group within the | 2174 | * find_busiest_group finds and returns the busiest CPU group within the |
| 2319 | * domain. It calculates and returns the amount of weighted load which | 2175 | * domain. It calculates and returns the amount of weighted load which |
| 2320 | * should be moved to restore balance via the imbalance parameter. | 2176 | * should be moved to restore balance via the imbalance parameter. |
| 2321 | */ | 2177 | */ |
| 2322 | static struct sched_group * | 2178 | static struct sched_group * |
| 2323 | find_busiest_group(struct sched_domain *sd, int this_cpu, | 2179 | find_busiest_group(struct sched_domain *sd, int this_cpu, |
| 2324 | unsigned long *imbalance, enum idle_type idle, int *sd_idle, | 2180 | unsigned long *imbalance, enum cpu_idle_type idle, |
| 2325 | cpumask_t *cpus, int *balance) | 2181 | int *sd_idle, cpumask_t *cpus, int *balance) |
| 2326 | { | 2182 | { |
| 2327 | struct sched_group *busiest = NULL, *this = NULL, *group = sd->groups; | 2183 | struct sched_group *busiest = NULL, *this = NULL, *group = sd->groups; |
| 2328 | unsigned long max_load, avg_load, total_load, this_load, total_pwr; | 2184 | unsigned long max_load, avg_load, total_load, this_load, total_pwr; |
| @@ -2340,9 +2196,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
| 2340 | max_load = this_load = total_load = total_pwr = 0; | 2196 | max_load = this_load = total_load = total_pwr = 0; |
| 2341 | busiest_load_per_task = busiest_nr_running = 0; | 2197 | busiest_load_per_task = busiest_nr_running = 0; |
| 2342 | this_load_per_task = this_nr_running = 0; | 2198 | this_load_per_task = this_nr_running = 0; |
| 2343 | if (idle == NOT_IDLE) | 2199 | if (idle == CPU_NOT_IDLE) |
| 2344 | load_idx = sd->busy_idx; | 2200 | load_idx = sd->busy_idx; |
| 2345 | else if (idle == NEWLY_IDLE) | 2201 | else if (idle == CPU_NEWLY_IDLE) |
| 2346 | load_idx = sd->newidle_idx; | 2202 | load_idx = sd->newidle_idx; |
| 2347 | else | 2203 | else |
| 2348 | load_idx = sd->idle_idx; | 2204 | load_idx = sd->idle_idx; |
| @@ -2386,7 +2242,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
| 2386 | 2242 | ||
| 2387 | avg_load += load; | 2243 | avg_load += load; |
| 2388 | sum_nr_running += rq->nr_running; | 2244 | sum_nr_running += rq->nr_running; |
| 2389 | sum_weighted_load += rq->raw_weighted_load; | 2245 | sum_weighted_load += weighted_cpuload(i); |
| 2390 | } | 2246 | } |
| 2391 | 2247 | ||
| 2392 | /* | 2248 | /* |
| @@ -2426,8 +2282,9 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
| 2426 | * Busy processors will not participate in power savings | 2282 | * Busy processors will not participate in power savings |
| 2427 | * balance. | 2283 | * balance. |
| 2428 | */ | 2284 | */ |
| 2429 | if (idle == NOT_IDLE || !(sd->flags & SD_POWERSAVINGS_BALANCE)) | 2285 | if (idle == CPU_NOT_IDLE || |
| 2430 | goto group_next; | 2286 | !(sd->flags & SD_POWERSAVINGS_BALANCE)) |
| 2287 | goto group_next; | ||
| 2431 | 2288 | ||
| 2432 | /* | 2289 | /* |
| 2433 | * If the local group is idle or completely loaded | 2290 | * If the local group is idle or completely loaded |
| @@ -2437,42 +2294,42 @@ find_busiest_group(struct sched_domain *sd, int this_cpu, | |||
| 2437 | !this_nr_running)) | 2294 | !this_nr_running)) |
| 2438 | power_savings_balance = 0; | 2295 | power_savings_balance = 0; |
| 2439 | 2296 | ||
| 2440 | /* | 2297 | /* |
| 2441 | * If a group is already running at full capacity or idle, | 2298 | * If a group is already running at full capacity or idle, |
| 2442 | * don't include that group in power savings calculations | 2299 | * don't include that group in power savings calculations |
| 2443 | */ | 2300 | */ |
| 2444 | if (!power_savings_balance || sum_nr_running >= group_capacity | 2301 | if (!power_savings_balance || sum_nr_running >= group_capacity |
| 2445 | || !sum_nr_running) | 2302 | || !sum_nr_running) |
| 2446 | goto group_next; | 2303 | goto group_next; |
| 2447 | 2304 | ||
| 2448 | /* | 2305 | /* |
| 2449 | * Calculate the group which has the least non-idle load. | 2306 | * Calculate the group which has the least non-idle load. |
| 2450 | * This is the group from where we need to pick up the load | 2307 | * This is the group from where we need to pick up the load |
| 2451 | * for saving power | 2308 | * for saving power |
| 2452 | */ | 2309 | */ |
| 2453 | if ((sum_nr_running < min_nr_running) || | 2310 | if ((sum_nr_running < min_nr_running) || |
| 2454 | (sum_nr_running == min_nr_running && | 2311 | (sum_nr_running == min_nr_running && |
| 2455 | first_cpu(group->cpumask) < | 2312 | first_cpu(group->cpumask) < |
| 2456 | first_cpu(group_min->cpumask))) { | 2313 | first_cpu(group_min->cpumask))) { |
| 2457 | group_min = group; | 2314 | group_min = group; |
| 2458 | min_nr_running = sum_nr_running; | 2315 | min_nr_running = sum_nr_running; |
| 2459 | min_load_per_task = sum_weighted_load / | 2316 | min_load_per_task = sum_weighted_load / |
| 2460 | sum_nr_running; | 2317 | sum_nr_running; |
| 2461 | } | 2318 | } |
| 2462 | 2319 | ||
| 2463 | /* | 2320 | /* |
| 2464 | * Calculate the group which is almost near its | 2321 | * Calculate the group which is almost near its |
| 2465 | * capacity but still has some space to pick up some load | 2322 | * capacity but still has some space to pick up some load |
| 2466 | * from other group and save more power | 2323 | * from other group and save more power |
| 2467 | */ | 2324 | */ |
| 2468 | if (sum_nr_running <= group_capacity - 1) { | 2325 | if (sum_nr_running <= group_capacity - 1) { |
| 2469 | if (sum_nr_running > leader_nr_running || | 2326 | if (sum_nr_running > leader_nr_running || |
| 2470 | (sum_nr_running == leader_nr_running && | 2327 | (sum_nr_running == leader_nr_running && |
| 2471 | first_cpu(group->cpumask) > | 2328 | first_cpu(group->cpumask) > |
| 2472 | first_cpu(group_leader->cpumask))) { | 2329 | first_cpu(group_leader->cpumask))) { |
| 2473 | group_leader = group; | 2330 | group_leader = group; |
| 2474 | leader_nr_running = sum_nr_running; | 2331 | leader_nr_running = sum_nr_running; |
| 2475 | } | 2332 | } |
| 2476 | } | 2333 | } |
| 2477 | group_next: | 2334 | group_next: |
| 2478 | #endif | 2335 | #endif |
| @@ -2527,7 +2384,7 @@ group_next: | |||
| 2527 | * a think about bumping its value to force at least one task to be | 2384 | * a think about bumping its value to force at least one task to be |
| 2528 | * moved | 2385 | * moved |
| 2529 | */ | 2386 | */ |
| 2530 | if (*imbalance < busiest_load_per_task) { | 2387 | if (*imbalance + SCHED_LOAD_SCALE_FUZZ < busiest_load_per_task/2) { |
| 2531 | unsigned long tmp, pwr_now, pwr_move; | 2388 | unsigned long tmp, pwr_now, pwr_move; |
| 2532 | unsigned int imbn; | 2389 | unsigned int imbn; |
| 2533 | 2390 | ||
| @@ -2541,7 +2398,8 @@ small_imbalance: | |||
| 2541 | } else | 2398 | } else |
| 2542 | this_load_per_task = SCHED_LOAD_SCALE; | 2399 | this_load_per_task = SCHED_LOAD_SCALE; |
| 2543 | 2400 | ||
| 2544 | if (max_load - this_load >= busiest_load_per_task * imbn) { | 2401 | if (max_load - this_load + SCHED_LOAD_SCALE_FUZZ >= |
| 2402 | busiest_load_per_task * imbn) { | ||
| 2545 | *imbalance = busiest_load_per_task; | 2403 | *imbalance = busiest_load_per_task; |
| 2546 | return busiest; | 2404 | return busiest; |
| 2547 | } | 2405 | } |
| @@ -2588,7 +2446,7 @@ small_imbalance: | |||
| 2588 | 2446 | ||
| 2589 | out_balanced: | 2447 | out_balanced: |
| 2590 | #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) | 2448 | #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) |
| 2591 | if (idle == NOT_IDLE || !(sd->flags & SD_POWERSAVINGS_BALANCE)) | 2449 | if (idle == CPU_NOT_IDLE || !(sd->flags & SD_POWERSAVINGS_BALANCE)) |
| 2592 | goto ret; | 2450 | goto ret; |
| 2593 | 2451 | ||
| 2594 | if (this == group_leader && group_leader != group_min) { | 2452 | if (this == group_leader && group_leader != group_min) { |
| @@ -2605,7 +2463,7 @@ ret: | |||
| 2605 | * find_busiest_queue - find the busiest runqueue among the cpus in group. | 2463 | * find_busiest_queue - find the busiest runqueue among the cpus in group. |
| 2606 | */ | 2464 | */ |
| 2607 | static struct rq * | 2465 | static struct rq * |
| 2608 | find_busiest_queue(struct sched_group *group, enum idle_type idle, | 2466 | find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle, |
| 2609 | unsigned long imbalance, cpumask_t *cpus) | 2467 | unsigned long imbalance, cpumask_t *cpus) |
| 2610 | { | 2468 | { |
| 2611 | struct rq *busiest = NULL, *rq; | 2469 | struct rq *busiest = NULL, *rq; |
| @@ -2613,17 +2471,19 @@ find_busiest_queue(struct sched_group *group, enum idle_type idle, | |||
| 2613 | int i; | 2471 | int i; |
| 2614 | 2472 | ||
| 2615 | for_each_cpu_mask(i, group->cpumask) { | 2473 | for_each_cpu_mask(i, group->cpumask) { |
| 2474 | unsigned long wl; | ||
| 2616 | 2475 | ||
| 2617 | if (!cpu_isset(i, *cpus)) | 2476 | if (!cpu_isset(i, *cpus)) |
| 2618 | continue; | 2477 | continue; |
| 2619 | 2478 | ||
| 2620 | rq = cpu_rq(i); | 2479 | rq = cpu_rq(i); |
| 2480 | wl = weighted_cpuload(i); | ||
| 2621 | 2481 | ||
| 2622 | if (rq->nr_running == 1 && rq->raw_weighted_load > imbalance) | 2482 | if (rq->nr_running == 1 && wl > imbalance) |
| 2623 | continue; | 2483 | continue; |
| 2624 | 2484 | ||
| 2625 | if (rq->raw_weighted_load > max_load) { | 2485 | if (wl > max_load) { |
| 2626 | max_load = rq->raw_weighted_load; | 2486 | max_load = wl; |
| 2627 | busiest = rq; | 2487 | busiest = rq; |
| 2628 | } | 2488 | } |
| 2629 | } | 2489 | } |
| @@ -2647,7 +2507,7 @@ static inline unsigned long minus_1_or_zero(unsigned long n) | |||
| 2647 | * tasks if there is an imbalance. | 2507 | * tasks if there is an imbalance. |
| 2648 | */ | 2508 | */ |
| 2649 | static int load_balance(int this_cpu, struct rq *this_rq, | 2509 | static int load_balance(int this_cpu, struct rq *this_rq, |
| 2650 | struct sched_domain *sd, enum idle_type idle, | 2510 | struct sched_domain *sd, enum cpu_idle_type idle, |
| 2651 | int *balance) | 2511 | int *balance) |
| 2652 | { | 2512 | { |
| 2653 | int nr_moved, all_pinned = 0, active_balance = 0, sd_idle = 0; | 2513 | int nr_moved, all_pinned = 0, active_balance = 0, sd_idle = 0; |
| @@ -2660,10 +2520,10 @@ static int load_balance(int this_cpu, struct rq *this_rq, | |||
| 2660 | /* | 2520 | /* |
| 2661 | * When power savings policy is enabled for the parent domain, idle | 2521 | * When power savings policy is enabled for the parent domain, idle |
| 2662 | * sibling can pick up load irrespective of busy siblings. In this case, | 2522 | * sibling can pick up load irrespective of busy siblings. In this case, |
| 2663 | * let the state of idle sibling percolate up as IDLE, instead of | 2523 | * let the state of idle sibling percolate up as CPU_IDLE, instead of |
| 2664 | * portraying it as NOT_IDLE. | 2524 | * portraying it as CPU_NOT_IDLE. |
| 2665 | */ | 2525 | */ |
| 2666 | if (idle != NOT_IDLE && sd->flags & SD_SHARE_CPUPOWER && | 2526 | if (idle != CPU_NOT_IDLE && sd->flags & SD_SHARE_CPUPOWER && |
| 2667 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) | 2527 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) |
| 2668 | sd_idle = 1; | 2528 | sd_idle = 1; |
| 2669 | 2529 | ||
| @@ -2797,7 +2657,7 @@ out_one_pinned: | |||
| 2797 | * Check this_cpu to ensure it is balanced within domain. Attempt to move | 2657 | * Check this_cpu to ensure it is balanced within domain. Attempt to move |
| 2798 | * tasks if there is an imbalance. | 2658 | * tasks if there is an imbalance. |
| 2799 | * | 2659 | * |
| 2800 | * Called from schedule when this_rq is about to become idle (NEWLY_IDLE). | 2660 | * Called from schedule when this_rq is about to become idle (CPU_NEWLY_IDLE). |
| 2801 | * this_rq is locked. | 2661 | * this_rq is locked. |
| 2802 | */ | 2662 | */ |
| 2803 | static int | 2663 | static int |
| @@ -2814,31 +2674,31 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd) | |||
| 2814 | * When power savings policy is enabled for the parent domain, idle | 2674 | * When power savings policy is enabled for the parent domain, idle |
| 2815 | * sibling can pick up load irrespective of busy siblings. In this case, | 2675 | * sibling can pick up load irrespective of busy siblings. In this case, |
| 2816 | * let the state of idle sibling percolate up as IDLE, instead of | 2676 | * let the state of idle sibling percolate up as IDLE, instead of |
| 2817 | * portraying it as NOT_IDLE. | 2677 | * portraying it as CPU_NOT_IDLE. |
| 2818 | */ | 2678 | */ |
| 2819 | if (sd->flags & SD_SHARE_CPUPOWER && | 2679 | if (sd->flags & SD_SHARE_CPUPOWER && |
| 2820 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) | 2680 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) |
| 2821 | sd_idle = 1; | 2681 | sd_idle = 1; |
| 2822 | 2682 | ||
| 2823 | schedstat_inc(sd, lb_cnt[NEWLY_IDLE]); | 2683 | schedstat_inc(sd, lb_cnt[CPU_NEWLY_IDLE]); |
| 2824 | redo: | 2684 | redo: |
| 2825 | group = find_busiest_group(sd, this_cpu, &imbalance, NEWLY_IDLE, | 2685 | group = find_busiest_group(sd, this_cpu, &imbalance, CPU_NEWLY_IDLE, |
| 2826 | &sd_idle, &cpus, NULL); | 2686 | &sd_idle, &cpus, NULL); |
| 2827 | if (!group) { | 2687 | if (!group) { |
| 2828 | schedstat_inc(sd, lb_nobusyg[NEWLY_IDLE]); | 2688 | schedstat_inc(sd, lb_nobusyg[CPU_NEWLY_IDLE]); |
| 2829 | goto out_balanced; | 2689 | goto out_balanced; |
| 2830 | } | 2690 | } |
| 2831 | 2691 | ||
| 2832 | busiest = find_busiest_queue(group, NEWLY_IDLE, imbalance, | 2692 | busiest = find_busiest_queue(group, CPU_NEWLY_IDLE, imbalance, |
| 2833 | &cpus); | 2693 | &cpus); |
| 2834 | if (!busiest) { | 2694 | if (!busiest) { |
| 2835 | schedstat_inc(sd, lb_nobusyq[NEWLY_IDLE]); | 2695 | schedstat_inc(sd, lb_nobusyq[CPU_NEWLY_IDLE]); |
| 2836 | goto out_balanced; | 2696 | goto out_balanced; |
| 2837 | } | 2697 | } |
| 2838 | 2698 | ||
| 2839 | BUG_ON(busiest == this_rq); | 2699 | BUG_ON(busiest == this_rq); |
| 2840 | 2700 | ||
| 2841 | schedstat_add(sd, lb_imbalance[NEWLY_IDLE], imbalance); | 2701 | schedstat_add(sd, lb_imbalance[CPU_NEWLY_IDLE], imbalance); |
| 2842 | 2702 | ||
| 2843 | nr_moved = 0; | 2703 | nr_moved = 0; |
| 2844 | if (busiest->nr_running > 1) { | 2704 | if (busiest->nr_running > 1) { |
| @@ -2846,7 +2706,7 @@ redo: | |||
| 2846 | double_lock_balance(this_rq, busiest); | 2706 | double_lock_balance(this_rq, busiest); |
| 2847 | nr_moved = move_tasks(this_rq, this_cpu, busiest, | 2707 | nr_moved = move_tasks(this_rq, this_cpu, busiest, |
| 2848 | minus_1_or_zero(busiest->nr_running), | 2708 | minus_1_or_zero(busiest->nr_running), |
| 2849 | imbalance, sd, NEWLY_IDLE, NULL); | 2709 | imbalance, sd, CPU_NEWLY_IDLE, NULL); |
| 2850 | spin_unlock(&busiest->lock); | 2710 | spin_unlock(&busiest->lock); |
| 2851 | 2711 | ||
| 2852 | if (!nr_moved) { | 2712 | if (!nr_moved) { |
| @@ -2857,7 +2717,7 @@ redo: | |||
| 2857 | } | 2717 | } |
| 2858 | 2718 | ||
| 2859 | if (!nr_moved) { | 2719 | if (!nr_moved) { |
| 2860 | schedstat_inc(sd, lb_failed[NEWLY_IDLE]); | 2720 | schedstat_inc(sd, lb_failed[CPU_NEWLY_IDLE]); |
| 2861 | if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && | 2721 | if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && |
| 2862 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) | 2722 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) |
| 2863 | return -1; | 2723 | return -1; |
| @@ -2867,7 +2727,7 @@ redo: | |||
| 2867 | return nr_moved; | 2727 | return nr_moved; |
| 2868 | 2728 | ||
| 2869 | out_balanced: | 2729 | out_balanced: |
| 2870 | schedstat_inc(sd, lb_balanced[NEWLY_IDLE]); | 2730 | schedstat_inc(sd, lb_balanced[CPU_NEWLY_IDLE]); |
| 2871 | if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && | 2731 | if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && |
| 2872 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) | 2732 | !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) |
| 2873 | return -1; | 2733 | return -1; |
| @@ -2883,28 +2743,33 @@ out_balanced: | |||
| 2883 | static void idle_balance(int this_cpu, struct rq *this_rq) | 2743 | static void idle_balance(int this_cpu, struct rq *this_rq) |
| 2884 | { | 2744 | { |
| 2885 | struct sched_domain *sd; | 2745 | struct sched_domain *sd; |
| 2886 | int pulled_task = 0; | 2746 | int pulled_task = -1; |
| 2887 | unsigned long next_balance = jiffies + 60 * HZ; | 2747 | unsigned long next_balance = jiffies + HZ; |
| 2888 | 2748 | ||
| 2889 | for_each_domain(this_cpu, sd) { | 2749 | for_each_domain(this_cpu, sd) { |
| 2890 | if (sd->flags & SD_BALANCE_NEWIDLE) { | 2750 | unsigned long interval; |
| 2751 | |||
| 2752 | if (!(sd->flags & SD_LOAD_BALANCE)) | ||
| 2753 | continue; | ||
| 2754 | |||
| 2755 | if (sd->flags & SD_BALANCE_NEWIDLE) | ||
| 2891 | /* If we've pulled tasks over stop searching: */ | 2756 | /* If we've pulled tasks over stop searching: */ |
| 2892 | pulled_task = load_balance_newidle(this_cpu, | 2757 | pulled_task = load_balance_newidle(this_cpu, |
| 2893 | this_rq, sd); | 2758 | this_rq, sd); |
| 2894 | if (time_after(next_balance, | 2759 | |
| 2895 | sd->last_balance + sd->balance_interval)) | 2760 | interval = msecs_to_jiffies(sd->balance_interval); |
| 2896 | next_balance = sd->last_balance | 2761 | if (time_after(next_balance, sd->last_balance + interval)) |
| 2897 | + sd->balance_interval; | 2762 | next_balance = sd->last_balance + interval; |
| 2898 | if (pulled_task) | 2763 | if (pulled_task) |
| 2899 | break; | 2764 | break; |
| 2900 | } | ||
| 2901 | } | 2765 | } |
| 2902 | if (!pulled_task) | 2766 | if (pulled_task || time_after(jiffies, this_rq->next_balance)) { |
| 2903 | /* | 2767 | /* |
| 2904 | * We are going idle. next_balance may be set based on | 2768 | * We are going idle. next_balance may be set based on |
| 2905 | * a busy processor. So reset next_balance. | 2769 | * a busy processor. So reset next_balance. |
| 2906 | */ | 2770 | */ |
| 2907 | this_rq->next_balance = next_balance; | 2771 | this_rq->next_balance = next_balance; |
| 2772 | } | ||
| 2908 | } | 2773 | } |
| 2909 | 2774 | ||
| 2910 | /* | 2775 | /* |
| @@ -2948,7 +2813,7 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) | |||
| 2948 | schedstat_inc(sd, alb_cnt); | 2813 | schedstat_inc(sd, alb_cnt); |
| 2949 | 2814 | ||
| 2950 | if (move_tasks(target_rq, target_cpu, busiest_rq, 1, | 2815 | if (move_tasks(target_rq, target_cpu, busiest_rq, 1, |
| 2951 | RTPRIO_TO_LOAD_WEIGHT(100), sd, SCHED_IDLE, | 2816 | RTPRIO_TO_LOAD_WEIGHT(100), sd, CPU_IDLE, |
| 2952 | NULL)) | 2817 | NULL)) |
| 2953 | schedstat_inc(sd, alb_pushed); | 2818 | schedstat_inc(sd, alb_pushed); |
| 2954 | else | 2819 | else |
| @@ -2957,32 +2822,6 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) | |||
| 2957 | spin_unlock(&target_rq->lock); | 2822 | spin_unlock(&target_rq->lock); |
| 2958 | } | 2823 | } |
| 2959 | 2824 | ||
| 2960 | static void update_load(struct rq *this_rq) | ||
| 2961 | { | ||
| 2962 | unsigned long this_load; | ||
| 2963 | unsigned int i, scale; | ||
| 2964 | |||
| 2965 | this_load = this_rq->raw_weighted_load; | ||
| 2966 | |||
| 2967 | /* Update our load: */ | ||
| 2968 | for (i = 0, scale = 1; i < 3; i++, scale += scale) { | ||
| 2969 | unsigned long old_load, new_load; | ||
| 2970 | |||
| 2971 | /* scale is effectively 1 << i now, and >> i divides by scale */ | ||
| 2972 | |||
| 2973 | old_load = this_rq->cpu_load[i]; | ||
| 2974 | new_load = this_load; | ||
| 2975 | /* | ||
| 2976 | * Round up the averaging division if load is increasing. This | ||
| 2977 | * prevents us from getting stuck on 9 if the load is 10, for | ||
| 2978 | * example. | ||
| 2979 | */ | ||
| 2980 | if (new_load > old_load) | ||
| 2981 | new_load += scale-1; | ||
| 2982 | this_rq->cpu_load[i] = (old_load*(scale-1) + new_load) >> i; | ||
| 2983 | } | ||
| 2984 | } | ||
| 2985 | |||
| 2986 | #ifdef CONFIG_NO_HZ | 2825 | #ifdef CONFIG_NO_HZ |
| 2987 | static struct { | 2826 | static struct { |
| 2988 | atomic_t load_balancer; | 2827 | atomic_t load_balancer; |
| @@ -3065,7 +2904,7 @@ static DEFINE_SPINLOCK(balancing); | |||
| 3065 | * | 2904 | * |
| 3066 | * Balancing parameters are set up in arch_init_sched_domains. | 2905 | * Balancing parameters are set up in arch_init_sched_domains. |
| 3067 | */ | 2906 | */ |
| 3068 | static inline void rebalance_domains(int cpu, enum idle_type idle) | 2907 | static inline void rebalance_domains(int cpu, enum cpu_idle_type idle) |
| 3069 | { | 2908 | { |
| 3070 | int balance = 1; | 2909 | int balance = 1; |
| 3071 | struct rq *rq = cpu_rq(cpu); | 2910 | struct rq *rq = cpu_rq(cpu); |
| @@ -3079,13 +2918,16 @@ static inline void rebalance_domains(int cpu, enum idle_type idle) | |||
| 3079 | continue; | 2918 | continue; |
| 3080 | 2919 | ||
| 3081 | interval = sd->balance_interval; | 2920 | interval = sd->balance_interval; |
| 3082 | if (idle != SCHED_IDLE) | 2921 | if (idle != CPU_IDLE) |
| 3083 | interval *= sd->busy_factor; | 2922 | interval *= sd->busy_factor; |
| 3084 | 2923 | ||
| 3085 | /* scale ms to jiffies */ | 2924 | /* scale ms to jiffies */ |
| 3086 | interval = msecs_to_jiffies(interval); | 2925 | interval = msecs_to_jiffies(interval); |
| 3087 | if (unlikely(!interval)) | 2926 | if (unlikely(!interval)) |
| 3088 | interval = 1; | 2927 | interval = 1; |
| 2928 | if (interval > HZ*NR_CPUS/10) | ||
| 2929 | interval = HZ*NR_CPUS/10; | ||
| 2930 | |||
| 3089 | 2931 | ||
| 3090 | if (sd->flags & SD_SERIALIZE) { | 2932 | if (sd->flags & SD_SERIALIZE) { |
| 3091 | if (!spin_trylock(&balancing)) | 2933 | if (!spin_trylock(&balancing)) |
| @@ -3099,7 +2941,7 @@ static inline void rebalance_domains(int cpu, enum idle_type idle) | |||
| 3099 | * longer idle, or one of our SMT siblings is | 2941 | * longer idle, or one of our SMT siblings is |
| 3100 | * not idle. | 2942 | * not idle. |
| 3101 | */ | 2943 | */ |
| 3102 | idle = NOT_IDLE; | 2944 | idle = CPU_NOT_IDLE; |
| 3103 | } | 2945 | } |
| 3104 | sd->last_balance = jiffies; | 2946 | sd->last_balance = jiffies; |
| 3105 | } | 2947 | } |
| @@ -3127,11 +2969,12 @@ out: | |||
| 3127 | */ | 2969 | */ |
| 3128 | static void run_rebalance_domains(struct softirq_action *h) | 2970 | static void run_rebalance_domains(struct softirq_action *h) |
| 3129 | { | 2971 | { |
| 3130 | int local_cpu = smp_processor_id(); | 2972 | int this_cpu = smp_processor_id(); |
| 3131 | struct rq *local_rq = cpu_rq(local_cpu); | 2973 | struct rq *this_rq = cpu_rq(this_cpu); |
| 3132 | enum idle_type idle = local_rq->idle_at_tick ? SCHED_IDLE : NOT_IDLE; | 2974 | enum cpu_idle_type idle = this_rq->idle_at_tick ? |
| 2975 | CPU_IDLE : CPU_NOT_IDLE; | ||
| 3133 | 2976 | ||
| 3134 | rebalance_domains(local_cpu, idle); | 2977 | rebalance_domains(this_cpu, idle); |
| 3135 | 2978 | ||
| 3136 | #ifdef CONFIG_NO_HZ | 2979 | #ifdef CONFIG_NO_HZ |
| 3137 | /* | 2980 | /* |
| @@ -3139,13 +2982,13 @@ static void run_rebalance_domains(struct softirq_action *h) | |||
| 3139 | * balancing on behalf of the other idle cpus whose ticks are | 2982 | * balancing on behalf of the other idle cpus whose ticks are |
| 3140 | * stopped. | 2983 | * stopped. |
| 3141 | */ | 2984 | */ |
| 3142 | if (local_rq->idle_at_tick && | 2985 | if (this_rq->idle_at_tick && |
| 3143 | atomic_read(&nohz.load_balancer) == local_cpu) { | 2986 | atomic_read(&nohz.load_balancer) == this_cpu) { |
| 3144 | cpumask_t cpus = nohz.cpu_mask; | 2987 | cpumask_t cpus = nohz.cpu_mask; |
| 3145 | struct rq *rq; | 2988 | struct rq *rq; |
| 3146 | int balance_cpu; | 2989 | int balance_cpu; |
| 3147 | 2990 | ||
| 3148 | cpu_clear(local_cpu, cpus); | 2991 | cpu_clear(this_cpu, cpus); |
| 3149 | for_each_cpu_mask(balance_cpu, cpus) { | 2992 | for_each_cpu_mask(balance_cpu, cpus) { |
| 3150 | /* | 2993 | /* |
| 3151 | * If this cpu gets work to do, stop the load balancing | 2994 | * If this cpu gets work to do, stop the load balancing |
| @@ -3158,8 +3001,8 @@ static void run_rebalance_domains(struct softirq_action *h) | |||
| 3158 | rebalance_domains(balance_cpu, SCHED_IDLE); | 3001 | rebalance_domains(balance_cpu, SCHED_IDLE); |
| 3159 | 3002 | ||
| 3160 | rq = cpu_rq(balance_cpu); | 3003 | rq = cpu_rq(balance_cpu); |
| 3161 | if (time_after(local_rq->next_balance, rq->next_balance)) | 3004 | if (time_after(this_rq->next_balance, rq->next_balance)) |
| 3162 | local_rq->next_balance = rq->next_balance; | 3005 | this_rq->next_balance = rq->next_balance; |
| 3163 | } | 3006 | } |
| 3164 | } | 3007 | } |
| 3165 | #endif | 3008 | #endif |
| @@ -3172,9 +3015,8 @@ static void run_rebalance_domains(struct softirq_action *h) | |||
| 3172 | * idle load balancing owner or decide to stop the periodic load balancing, | 3015 | * idle load balancing owner or decide to stop the periodic load balancing, |
| 3173 | * if the whole system is idle. | 3016 | * if the whole system is idle. |
| 3174 | */ | 3017 | */ |
| 3175 | static inline void trigger_load_balance(int cpu) | 3018 | static inline void trigger_load_balance(struct rq *rq, int cpu) |
| 3176 | { | 3019 | { |
| 3177 | struct rq *rq = cpu_rq(cpu); | ||
| 3178 | #ifdef CONFIG_NO_HZ | 3020 | #ifdef CONFIG_NO_HZ |
| 3179 | /* | 3021 | /* |
| 3180 | * If we were in the nohz mode recently and busy at the current | 3022 | * If we were in the nohz mode recently and busy at the current |
| @@ -3226,13 +3068,29 @@ static inline void trigger_load_balance(int cpu) | |||
| 3226 | if (time_after_eq(jiffies, rq->next_balance)) | 3068 | if (time_after_eq(jiffies, rq->next_balance)) |
| 3227 | raise_softirq(SCHED_SOFTIRQ); | 3069 | raise_softirq(SCHED_SOFTIRQ); |
| 3228 | } | 3070 | } |
| 3229 | #else | 3071 | |
| 3072 | #else /* CONFIG_SMP */ | ||
| 3073 | |||
| 3230 | /* | 3074 | /* |
| 3231 | * on UP we do not need to balance between CPUs: | 3075 | * on UP we do not need to balance between CPUs: |
| 3232 | */ | 3076 | */ |
| 3233 | static inline void idle_balance(int cpu, struct rq *rq) | 3077 | static inline void idle_balance(int cpu, struct rq *rq) |
| 3234 | { | 3078 | { |
| 3235 | } | 3079 | } |
| 3080 | |||
| 3081 | /* Avoid "used but not defined" warning on UP */ | ||
| 3082 | static int balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, | ||
| 3083 | unsigned long max_nr_move, unsigned long max_load_move, | ||
| 3084 | struct sched_domain *sd, enum cpu_idle_type idle, | ||
| 3085 | int *all_pinned, unsigned long *load_moved, | ||
| 3086 | int this_best_prio, int best_prio, int best_prio_seen, | ||
| 3087 | struct rq_iterator *iterator) | ||
| 3088 | { | ||
| 3089 | *load_moved = 0; | ||
| 3090 | |||
| 3091 | return 0; | ||
| 3092 | } | ||
| 3093 | |||
| 3236 | #endif | 3094 | #endif |
| 3237 | 3095 | ||
| 3238 | DEFINE_PER_CPU(struct kernel_stat, kstat); | 3096 | DEFINE_PER_CPU(struct kernel_stat, kstat); |
| @@ -3240,54 +3098,28 @@ DEFINE_PER_CPU(struct kernel_stat, kstat); | |||
| 3240 | EXPORT_PER_CPU_SYMBOL(kstat); | 3098 | EXPORT_PER_CPU_SYMBOL(kstat); |
| 3241 | 3099 | ||
| 3242 | /* | 3100 | /* |
| 3243 | * This is called on clock ticks and on context switches. | 3101 | * Return p->sum_exec_runtime plus any more ns on the sched_clock |
| 3244 | * Bank in p->sched_time the ns elapsed since the last tick or switch. | 3102 | * that have not yet been banked in case the task is currently running. |
| 3245 | */ | 3103 | */ |
| 3246 | static inline void | 3104 | unsigned long long task_sched_runtime(struct task_struct *p) |
| 3247 | update_cpu_clock(struct task_struct *p, struct rq *rq, unsigned long long now) | ||
| 3248 | { | ||
| 3249 | p->sched_time += now - p->last_ran; | ||
| 3250 | p->last_ran = rq->most_recent_timestamp = now; | ||
| 3251 | } | ||
| 3252 | |||
| 3253 | /* | ||
| 3254 | * Return current->sched_time plus any more ns on the sched_clock | ||
| 3255 | * that have not yet been banked. | ||
| 3256 | */ | ||
| 3257 | unsigned long long current_sched_time(const struct task_struct *p) | ||
| 3258 | { | 3105 | { |
| 3259 | unsigned long long ns; | ||
| 3260 | unsigned long flags; | 3106 | unsigned long flags; |
| 3107 | u64 ns, delta_exec; | ||
| 3108 | struct rq *rq; | ||
| 3261 | 3109 | ||
| 3262 | local_irq_save(flags); | 3110 | rq = task_rq_lock(p, &flags); |
| 3263 | ns = p->sched_time + sched_clock() - p->last_ran; | 3111 | ns = p->se.sum_exec_runtime; |
| 3264 | local_irq_restore(flags); | 3112 | if (rq->curr == p) { |
| 3113 | delta_exec = rq_clock(rq) - p->se.exec_start; | ||
| 3114 | if ((s64)delta_exec > 0) | ||
| 3115 | ns += delta_exec; | ||
| 3116 | } | ||
| 3117 | task_rq_unlock(rq, &flags); | ||
| 3265 | 3118 | ||
| 3266 | return ns; | 3119 | return ns; |
| 3267 | } | 3120 | } |
| 3268 | 3121 | ||
| 3269 | /* | 3122 | /* |
| 3270 | * We place interactive tasks back into the active array, if possible. | ||
| 3271 | * | ||
| 3272 | * To guarantee that this does not starve expired tasks we ignore the | ||
| 3273 | * interactivity of a task if the first expired task had to wait more | ||
| 3274 | * than a 'reasonable' amount of time. This deadline timeout is | ||
| 3275 | * load-dependent, as the frequency of array switched decreases with | ||
| 3276 | * increasing number of running tasks. We also ignore the interactivity | ||
| 3277 | * if a better static_prio task has expired: | ||
| 3278 | */ | ||
| 3279 | static inline int expired_starving(struct rq *rq) | ||
| 3280 | { | ||
| 3281 | if (rq->curr->static_prio > rq->best_expired_prio) | ||
| 3282 | return 1; | ||
| 3283 | if (!STARVATION_LIMIT || !rq->expired_timestamp) | ||
| 3284 | return 0; | ||
| 3285 | if (jiffies - rq->expired_timestamp > STARVATION_LIMIT * rq->nr_running) | ||
| 3286 | return 1; | ||
| 3287 | return 0; | ||
| 3288 | } | ||
| 3289 | |||
| 3290 | /* | ||
| 3291 | * Account user cpu time to a process. | 3123 | * Account user cpu time to a process. |
| 3292 | * @p: the process that the cpu time gets accounted to | 3124 | * @p: the process that the cpu time gets accounted to |
| 3293 | * @hardirq_offset: the offset to subtract from hardirq_count() | 3125 | * @hardirq_offset: the offset to subtract from hardirq_count() |
| @@ -3360,81 +3192,6 @@ void account_steal_time(struct task_struct *p, cputime_t steal) | |||
| 3360 | cpustat->steal = cputime64_add(cpustat->steal, tmp); | 3192 | cpustat->steal = cputime64_add(cpustat->steal, tmp); |
| 3361 | } | 3193 | } |
| 3362 | 3194 | ||
| 3363 | static void task_running_tick(struct rq *rq, struct task_struct *p) | ||
| 3364 | { | ||
| 3365 | if (p->array != rq->active) { | ||
| 3366 | /* Task has expired but was not scheduled yet */ | ||
| 3367 | set_tsk_need_resched(p); | ||
| 3368 | return; | ||
| 3369 | } | ||
| 3370 | spin_lock(&rq->lock); | ||
| 3371 | /* | ||
| 3372 | * The task was running during this tick - update the | ||
| 3373 | * time slice counter. Note: we do not update a thread's | ||
| 3374 | * priority until it either goes to sleep or uses up its | ||
| 3375 | * timeslice. This makes it possible for interactive tasks | ||
| 3376 | * to use up their timeslices at their highest priority levels. | ||
| 3377 | */ | ||
| 3378 | if (rt_task(p)) { | ||
| 3379 | /* | ||
| 3380 | * RR tasks need a special form of timeslice management. | ||
| 3381 | * FIFO tasks have no timeslices. | ||
| 3382 | */ | ||
| 3383 | if ((p->policy == SCHED_RR) && !--p->time_slice) { | ||
| 3384 | p->time_slice = task_timeslice(p); | ||
| 3385 | p->first_time_slice = 0; | ||
| 3386 | set_tsk_need_resched(p); | ||
| 3387 | |||
| 3388 | /* put it at the end of the queue: */ | ||
| 3389 | requeue_task(p, rq->active); | ||
| 3390 | } | ||
| 3391 | goto out_unlock; | ||
| 3392 | } | ||
| 3393 | if (!--p->time_slice) { | ||
| 3394 | dequeue_task(p, rq->active); | ||
| 3395 | set_tsk_need_resched(p); | ||
| 3396 | p->prio = effective_prio(p); | ||
| 3397 | p->time_slice = task_timeslice(p); | ||
| 3398 | p->first_time_slice = 0; | ||
| 3399 | |||
| 3400 | if (!rq->expired_timestamp) | ||
| 3401 | rq->expired_timestamp = jiffies; | ||
| 3402 | if (!TASK_INTERACTIVE(p) || expired_starving(rq)) { | ||
| 3403 | enqueue_task(p, rq->expired); | ||
| 3404 | if (p->static_prio < rq->best_expired_prio) | ||
| 3405 | rq->best_expired_prio = p->static_prio; | ||
| 3406 | } else | ||
| 3407 | enqueue_task(p, rq->active); | ||
| 3408 | } else { | ||
| 3409 | /* | ||
| 3410 | * Prevent a too long timeslice allowing a task to monopolize | ||
| 3411 | * the CPU. We do this by splitting up the timeslice into | ||
| 3412 | * smaller pieces. | ||
| 3413 | * | ||
| 3414 | * Note: this does not mean the task's timeslices expire or | ||
| 3415 | * get lost in any way, they just might be preempted by | ||
| 3416 | * another task of equal priority. (one with higher | ||
| 3417 | * priority would have preempted this task already.) We | ||
| 3418 | * requeue this task to the end of the list on this priority | ||
| 3419 | * level, which is in essence a round-robin of tasks with | ||
| 3420 | * equal priority. | ||
| 3421 | * | ||
| 3422 | * This only applies to tasks in the interactive | ||
| 3423 | * delta range with at least TIMESLICE_GRANULARITY to requeue. | ||
| 3424 | */ | ||
| 3425 | if (TASK_INTERACTIVE(p) && !((task_timeslice(p) - | ||
| 3426 | p->time_slice) % TIMESLICE_GRANULARITY(p)) && | ||
| 3427 | (p->time_slice >= TIMESLICE_GRANULARITY(p)) && | ||
| 3428 | (p->array == rq->active)) { | ||
| 3429 | |||
| 3430 | requeue_task(p, rq->active); | ||
| 3431 | set_tsk_need_resched(p); | ||
| 3432 | } | ||
| 3433 | } | ||
| 3434 | out_unlock: | ||
| 3435 | spin_unlock(&rq->lock); | ||
| 3436 | } | ||
| 3437 | |||
| 3438 | /* | 3195 | /* |
| 3439 | * This function gets called by the timer code, with HZ frequency. | 3196 | * This function gets called by the timer code, with HZ frequency. |
| 3440 | * We call it with interrupts disabled. | 3197 | * We call it with interrupts disabled. |
| @@ -3444,20 +3201,19 @@ out_unlock: | |||
| 3444 | */ | 3201 | */ |
| 3445 | void scheduler_tick(void) | 3202 | void scheduler_tick(void) |
| 3446 | { | 3203 | { |
| 3447 | unsigned long long now = sched_clock(); | ||
| 3448 | struct task_struct *p = current; | ||
| 3449 | int cpu = smp_processor_id(); | 3204 | int cpu = smp_processor_id(); |
| 3450 | int idle_at_tick = idle_cpu(cpu); | ||
| 3451 | struct rq *rq = cpu_rq(cpu); | 3205 | struct rq *rq = cpu_rq(cpu); |
| 3206 | struct task_struct *curr = rq->curr; | ||
| 3452 | 3207 | ||
| 3453 | update_cpu_clock(p, rq, now); | 3208 | spin_lock(&rq->lock); |
| 3209 | if (curr != rq->idle) /* FIXME: needed? */ | ||
| 3210 | curr->sched_class->task_tick(rq, curr); | ||
| 3211 | update_cpu_load(rq); | ||
| 3212 | spin_unlock(&rq->lock); | ||
| 3454 | 3213 | ||
| 3455 | if (!idle_at_tick) | ||
| 3456 | task_running_tick(rq, p); | ||
| 3457 | #ifdef CONFIG_SMP | 3214 | #ifdef CONFIG_SMP |
| 3458 | update_load(rq); | 3215 | rq->idle_at_tick = idle_cpu(cpu); |
| 3459 | rq->idle_at_tick = idle_at_tick; | 3216 | trigger_load_balance(rq, cpu); |
| 3460 | trigger_load_balance(cpu); | ||
| 3461 | #endif | 3217 | #endif |
| 3462 | } | 3218 | } |
| 3463 | 3219 | ||
| @@ -3499,170 +3255,129 @@ EXPORT_SYMBOL(sub_preempt_count); | |||
| 3499 | 3255 | ||
| 3500 | #endif | 3256 | #endif |
| 3501 | 3257 | ||
| 3502 | static inline int interactive_sleep(enum sleep_type sleep_type) | 3258 | /* |
| 3259 | * Print scheduling while atomic bug: | ||
| 3260 | */ | ||
| 3261 | static noinline void __schedule_bug(struct task_struct *prev) | ||
| 3503 | { | 3262 | { |
| 3504 | return (sleep_type == SLEEP_INTERACTIVE || | 3263 | printk(KERN_ERR "BUG: scheduling while atomic: %s/0x%08x/%d\n", |
| 3505 | sleep_type == SLEEP_INTERRUPTED); | 3264 | prev->comm, preempt_count(), prev->pid); |
| 3265 | debug_show_held_locks(prev); | ||
| 3266 | if (irqs_disabled()) | ||
| 3267 | print_irqtrace_events(prev); | ||
| 3268 | dump_stack(); | ||
| 3506 | } | 3269 | } |
| 3507 | 3270 | ||
| 3508 | /* | 3271 | /* |
| 3509 | * schedule() is the main scheduler function. | 3272 | * Various schedule()-time debugging checks and statistics: |
| 3510 | */ | 3273 | */ |
| 3511 | asmlinkage void __sched schedule(void) | 3274 | static inline void schedule_debug(struct task_struct *prev) |
| 3512 | { | 3275 | { |
| 3513 | struct task_struct *prev, *next; | ||
| 3514 | struct prio_array *array; | ||
| 3515 | struct list_head *queue; | ||
| 3516 | unsigned long long now; | ||
| 3517 | unsigned long run_time; | ||
| 3518 | int cpu, idx, new_prio; | ||
| 3519 | long *switch_count; | ||
| 3520 | struct rq *rq; | ||
| 3521 | |||
| 3522 | /* | 3276 | /* |
| 3523 | * Test if we are atomic. Since do_exit() needs to call into | 3277 | * Test if we are atomic. Since do_exit() needs to call into |
| 3524 | * schedule() atomically, we ignore that path for now. | 3278 | * schedule() atomically, we ignore that path for now. |
| 3525 | * Otherwise, whine if we are scheduling when we should not be. | 3279 | * Otherwise, whine if we are scheduling when we should not be. |
| 3526 | */ | 3280 | */ |
| 3527 | if (unlikely(in_atomic() && !current->exit_state)) { | 3281 | if (unlikely(in_atomic_preempt_off()) && unlikely(!prev->exit_state)) |
| 3528 | printk(KERN_ERR "BUG: scheduling while atomic: " | 3282 | __schedule_bug(prev); |
| 3529 | "%s/0x%08x/%d\n", | ||
| 3530 | current->comm, preempt_count(), current->pid); | ||
| 3531 | debug_show_held_locks(current); | ||
| 3532 | if (irqs_disabled()) | ||
| 3533 | print_irqtrace_events(current); | ||
| 3534 | dump_stack(); | ||
| 3535 | } | ||
| 3536 | profile_hit(SCHED_PROFILING, __builtin_return_address(0)); | ||
| 3537 | 3283 | ||
| 3538 | need_resched: | 3284 | profile_hit(SCHED_PROFILING, __builtin_return_address(0)); |
| 3539 | preempt_disable(); | ||
| 3540 | prev = current; | ||
| 3541 | release_kernel_lock(prev); | ||
| 3542 | need_resched_nonpreemptible: | ||
| 3543 | rq = this_rq(); | ||
| 3544 | 3285 | ||
| 3545 | /* | 3286 | schedstat_inc(this_rq(), sched_cnt); |
| 3546 | * The idle thread is not allowed to schedule! | 3287 | } |
| 3547 | * Remove this check after it has been exercised a bit. | ||
| 3548 | */ | ||
| 3549 | if (unlikely(prev == rq->idle) && prev->state != TASK_RUNNING) { | ||
| 3550 | printk(KERN_ERR "bad: scheduling from the idle thread!\n"); | ||
| 3551 | dump_stack(); | ||
| 3552 | } | ||
| 3553 | 3288 | ||
| 3554 | schedstat_inc(rq, sched_cnt); | 3289 | /* |
| 3555 | now = sched_clock(); | 3290 | * Pick up the highest-prio task: |
| 3556 | if (likely((long long)(now - prev->timestamp) < NS_MAX_SLEEP_AVG)) { | 3291 | */ |
| 3557 | run_time = now - prev->timestamp; | 3292 | static inline struct task_struct * |
| 3558 | if (unlikely((long long)(now - prev->timestamp) < 0)) | 3293 | pick_next_task(struct rq *rq, struct task_struct *prev, u64 now) |
| 3559 | run_time = 0; | 3294 | { |
| 3560 | } else | 3295 | struct sched_class *class; |
| 3561 | run_time = NS_MAX_SLEEP_AVG; | 3296 | struct task_struct *p; |
| 3562 | 3297 | ||
| 3563 | /* | 3298 | /* |
| 3564 | * Tasks charged proportionately less run_time at high sleep_avg to | 3299 | * Optimization: we know that if all tasks are in |
| 3565 | * delay them losing their interactive status | 3300 | * the fair class we can call that function directly: |
| 3566 | */ | 3301 | */ |
| 3567 | run_time /= (CURRENT_BONUS(prev) ? : 1); | 3302 | if (likely(rq->nr_running == rq->cfs.nr_running)) { |
| 3568 | 3303 | p = fair_sched_class.pick_next_task(rq, now); | |
| 3569 | spin_lock_irq(&rq->lock); | 3304 | if (likely(p)) |
| 3570 | 3305 | return p; | |
| 3571 | switch_count = &prev->nivcsw; | ||
| 3572 | if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { | ||
| 3573 | switch_count = &prev->nvcsw; | ||
| 3574 | if (unlikely((prev->state & TASK_INTERRUPTIBLE) && | ||
| 3575 | unlikely(signal_pending(prev)))) | ||
| 3576 | prev->state = TASK_RUNNING; | ||
| 3577 | else { | ||
| 3578 | if (prev->state == TASK_UNINTERRUPTIBLE) | ||
| 3579 | rq->nr_uninterruptible++; | ||
| 3580 | deactivate_task(prev, rq); | ||
| 3581 | } | ||
| 3582 | } | 3306 | } |
| 3583 | 3307 | ||
| 3584 | cpu = smp_processor_id(); | 3308 | class = sched_class_highest; |
| 3585 | if (unlikely(!rq->nr_running)) { | 3309 | for ( ; ; ) { |
| 3586 | idle_balance(cpu, rq); | 3310 | p = class->pick_next_task(rq, now); |
| 3587 | if (!rq->nr_running) { | 3311 | if (p) |
| 3588 | next = rq->idle; | 3312 | return p; |
| 3589 | rq->expired_timestamp = 0; | ||
| 3590 | goto switch_tasks; | ||
| 3591 | } | ||
| 3592 | } | ||
| 3593 | |||
| 3594 | array = rq->active; | ||
| 3595 | if (unlikely(!array->nr_active)) { | ||
| 3596 | /* | 3313 | /* |
| 3597 | * Switch the active and expired arrays. | 3314 | * Will never be NULL as the idle class always |
| 3315 | * returns a non-NULL p: | ||
| 3598 | */ | 3316 | */ |
| 3599 | schedstat_inc(rq, sched_switch); | 3317 | class = class->next; |
| 3600 | rq->active = rq->expired; | ||
| 3601 | rq->expired = array; | ||
| 3602 | array = rq->active; | ||
| 3603 | rq->expired_timestamp = 0; | ||
| 3604 | rq->best_expired_prio = MAX_PRIO; | ||
| 3605 | } | 3318 | } |
| 3319 | } | ||
| 3320 | |||
| 3321 | /* | ||
| 3322 | * schedule() is the main scheduler function. | ||
| 3323 | */ | ||
| 3324 | asmlinkage void __sched schedule(void) | ||
| 3325 | { | ||
| 3326 | struct task_struct *prev, *next; | ||
| 3327 | long *switch_count; | ||
| 3328 | struct rq *rq; | ||
| 3329 | u64 now; | ||
| 3330 | int cpu; | ||
| 3606 | 3331 | ||
| 3607 | idx = sched_find_first_bit(array->bitmap); | 3332 | need_resched: |
| 3608 | queue = array->queue + idx; | 3333 | preempt_disable(); |
| 3609 | next = list_entry(queue->next, struct task_struct, run_list); | 3334 | cpu = smp_processor_id(); |
| 3335 | rq = cpu_rq(cpu); | ||
| 3336 | rcu_qsctr_inc(cpu); | ||
| 3337 | prev = rq->curr; | ||
| 3338 | switch_count = &prev->nivcsw; | ||
| 3610 | 3339 | ||
| 3611 | if (!rt_task(next) && interactive_sleep(next->sleep_type)) { | 3340 | release_kernel_lock(prev); |
| 3612 | unsigned long long delta = now - next->timestamp; | 3341 | need_resched_nonpreemptible: |
| 3613 | if (unlikely((long long)(now - next->timestamp) < 0)) | ||
| 3614 | delta = 0; | ||
| 3615 | 3342 | ||
| 3616 | if (next->sleep_type == SLEEP_INTERACTIVE) | 3343 | schedule_debug(prev); |
| 3617 | delta = delta * (ON_RUNQUEUE_WEIGHT * 128 / 100) / 128; | ||
| 3618 | 3344 | ||
| 3619 | array = next->array; | 3345 | spin_lock_irq(&rq->lock); |
| 3620 | new_prio = recalc_task_prio(next, next->timestamp + delta); | 3346 | clear_tsk_need_resched(prev); |
| 3621 | 3347 | ||
| 3622 | if (unlikely(next->prio != new_prio)) { | 3348 | if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { |
| 3623 | dequeue_task(next, array); | 3349 | if (unlikely((prev->state & TASK_INTERRUPTIBLE) && |
| 3624 | next->prio = new_prio; | 3350 | unlikely(signal_pending(prev)))) { |
| 3625 | enqueue_task(next, array); | 3351 | prev->state = TASK_RUNNING; |
| 3352 | } else { | ||
| 3353 | deactivate_task(rq, prev, 1); | ||
| 3626 | } | 3354 | } |
| 3355 | switch_count = &prev->nvcsw; | ||
| 3627 | } | 3356 | } |
| 3628 | next->sleep_type = SLEEP_NORMAL; | ||
| 3629 | switch_tasks: | ||
| 3630 | if (next == rq->idle) | ||
| 3631 | schedstat_inc(rq, sched_goidle); | ||
| 3632 | prefetch(next); | ||
| 3633 | prefetch_stack(next); | ||
| 3634 | clear_tsk_need_resched(prev); | ||
| 3635 | rcu_qsctr_inc(task_cpu(prev)); | ||
| 3636 | 3357 | ||
| 3637 | update_cpu_clock(prev, rq, now); | 3358 | if (unlikely(!rq->nr_running)) |
| 3359 | idle_balance(cpu, rq); | ||
| 3638 | 3360 | ||
| 3639 | prev->sleep_avg -= run_time; | 3361 | now = __rq_clock(rq); |
| 3640 | if ((long)prev->sleep_avg <= 0) | 3362 | prev->sched_class->put_prev_task(rq, prev, now); |
| 3641 | prev->sleep_avg = 0; | 3363 | next = pick_next_task(rq, prev, now); |
| 3642 | prev->timestamp = prev->last_ran = now; | ||
| 3643 | 3364 | ||
| 3644 | sched_info_switch(prev, next); | 3365 | sched_info_switch(prev, next); |
| 3366 | |||
| 3645 | if (likely(prev != next)) { | 3367 | if (likely(prev != next)) { |
| 3646 | next->timestamp = next->last_ran = now; | ||
| 3647 | rq->nr_switches++; | 3368 | rq->nr_switches++; |
| 3648 | rq->curr = next; | 3369 | rq->curr = next; |
| 3649 | ++*switch_count; | 3370 | ++*switch_count; |
| 3650 | 3371 | ||
| 3651 | prepare_task_switch(rq, next); | 3372 | context_switch(rq, prev, next); /* unlocks the rq */ |
| 3652 | prev = context_switch(rq, prev, next); | ||
| 3653 | barrier(); | ||
| 3654 | /* | ||
| 3655 | * this_rq must be evaluated again because prev may have moved | ||
| 3656 | * CPUs since it called schedule(), thus the 'rq' on its stack | ||
| 3657 | * frame will be invalid. | ||
| 3658 | */ | ||
| 3659 | finish_task_switch(this_rq(), prev); | ||
| 3660 | } else | 3373 | } else |
| 3661 | spin_unlock_irq(&rq->lock); | 3374 | spin_unlock_irq(&rq->lock); |
| 3662 | 3375 | ||
| 3663 | prev = current; | 3376 | if (unlikely(reacquire_kernel_lock(current) < 0)) { |
| 3664 | if (unlikely(reacquire_kernel_lock(prev) < 0)) | 3377 | cpu = smp_processor_id(); |
| 3378 | rq = cpu_rq(cpu); | ||
| 3665 | goto need_resched_nonpreemptible; | 3379 | goto need_resched_nonpreemptible; |
| 3380 | } | ||
| 3666 | preempt_enable_no_resched(); | 3381 | preempt_enable_no_resched(); |
| 3667 | if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) | 3382 | if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) |
| 3668 | goto need_resched; | 3383 | goto need_resched; |
| @@ -3990,74 +3705,85 @@ out: | |||
| 3990 | } | 3705 | } |
| 3991 | EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); | 3706 | EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); |
| 3992 | 3707 | ||
| 3993 | 3708 | static inline void | |
| 3994 | #define SLEEP_ON_VAR \ | 3709 | sleep_on_head(wait_queue_head_t *q, wait_queue_t *wait, unsigned long *flags) |
| 3995 | unsigned long flags; \ | 3710 | { |
| 3996 | wait_queue_t wait; \ | 3711 | spin_lock_irqsave(&q->lock, *flags); |
| 3997 | init_waitqueue_entry(&wait, current); | 3712 | __add_wait_queue(q, wait); |
| 3998 | |||
| 3999 | #define SLEEP_ON_HEAD \ | ||
| 4000 | spin_lock_irqsave(&q->lock,flags); \ | ||
| 4001 | __add_wait_queue(q, &wait); \ | ||
| 4002 | spin_unlock(&q->lock); | 3713 | spin_unlock(&q->lock); |
| 3714 | } | ||
| 4003 | 3715 | ||
| 4004 | #define SLEEP_ON_TAIL \ | 3716 | static inline void |
| 4005 | spin_lock_irq(&q->lock); \ | 3717 | sleep_on_tail(wait_queue_head_t *q, wait_queue_t *wait, unsigned long *flags) |
| 4006 | __remove_wait_queue(q, &wait); \ | 3718 | { |
| 4007 | spin_unlock_irqrestore(&q->lock, flags); | 3719 | spin_lock_irq(&q->lock); |
| 3720 | __remove_wait_queue(q, wait); | ||
| 3721 | spin_unlock_irqrestore(&q->lock, *flags); | ||
| 3722 | } | ||
| 4008 | 3723 | ||
| 4009 | void fastcall __sched interruptible_sleep_on(wait_queue_head_t *q) | 3724 | void __sched interruptible_sleep_on(wait_queue_head_t *q) |
| 4010 | { | 3725 | { |
| 4011 | SLEEP_ON_VAR | 3726 | unsigned long flags; |
| 3727 | wait_queue_t wait; | ||
| 3728 | |||
| 3729 | init_waitqueue_entry(&wait, current); | ||
| 4012 | 3730 | ||
| 4013 | current->state = TASK_INTERRUPTIBLE; | 3731 | current->state = TASK_INTERRUPTIBLE; |
| 4014 | 3732 | ||
| 4015 | SLEEP_ON_HEAD | 3733 | sleep_on_head(q, &wait, &flags); |
| 4016 | schedule(); | 3734 | schedule(); |
| 4017 | SLEEP_ON_TAIL | 3735 | sleep_on_tail(q, &wait, &flags); |
| 4018 | } | 3736 | } |
| 4019 | EXPORT_SYMBOL(interruptible_sleep_on); | 3737 | EXPORT_SYMBOL(interruptible_sleep_on); |
| 4020 | 3738 | ||
| 4021 | long fastcall __sched | 3739 | long __sched |
| 4022 | interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) | 3740 | interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) |
| 4023 | { | 3741 | { |
| 4024 | SLEEP_ON_VAR | 3742 | unsigned long flags; |
| 3743 | wait_queue_t wait; | ||
| 3744 | |||
| 3745 | init_waitqueue_entry(&wait, current); | ||
| 4025 | 3746 | ||
| 4026 | current->state = TASK_INTERRUPTIBLE; | 3747 | current->state = TASK_INTERRUPTIBLE; |
| 4027 | 3748 | ||
| 4028 | SLEEP_ON_HEAD | 3749 | sleep_on_head(q, &wait, &flags); |
| 4029 | timeout = schedule_timeout(timeout); | 3750 | timeout = schedule_timeout(timeout); |
| 4030 | SLEEP_ON_TAIL | 3751 | sleep_on_tail(q, &wait, &flags); |
| 4031 | 3752 | ||
| 4032 | return timeout; | 3753 | return timeout; |
| 4033 | } | 3754 | } |
| 4034 | EXPORT_SYMBOL(interruptible_sleep_on_timeout); | 3755 | EXPORT_SYMBOL(interruptible_sleep_on_timeout); |
| 4035 | 3756 | ||
| 4036 | void fastcall __sched sleep_on(wait_queue_head_t *q) | 3757 | void __sched sleep_on(wait_queue_head_t *q) |
| 4037 | { | 3758 | { |
| 4038 | SLEEP_ON_VAR | 3759 | unsigned long flags; |
| 3760 | wait_queue_t wait; | ||
| 3761 | |||
| 3762 | init_waitqueue_entry(&wait, current); | ||
| 4039 | 3763 | ||
| 4040 | current->state = TASK_UNINTERRUPTIBLE; | 3764 | current->state = TASK_UNINTERRUPTIBLE; |
| 4041 | 3765 | ||
| 4042 | SLEEP_ON_HEAD | 3766 | sleep_on_head(q, &wait, &flags); |
| 4043 | schedule(); | 3767 | schedule(); |
| 4044 | SLEEP_ON_TAIL | 3768 | sleep_on_tail(q, &wait, &flags); |
| 4045 | } | 3769 | } |
| 4046 | EXPORT_SYMBOL(sleep_on); | 3770 | EXPORT_SYMBOL(sleep_on); |
| 4047 | 3771 | ||
| 4048 | long fastcall __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) | 3772 | long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) |
| 4049 | { | 3773 | { |
| 4050 | SLEEP_ON_VAR | 3774 | unsigned long flags; |
| 3775 | wait_queue_t wait; | ||
| 3776 | |||
| 3777 | init_waitqueue_entry(&wait, current); | ||
| 4051 | 3778 | ||
| 4052 | current->state = TASK_UNINTERRUPTIBLE; | 3779 | current->state = TASK_UNINTERRUPTIBLE; |
| 4053 | 3780 | ||
| 4054 | SLEEP_ON_HEAD | 3781 | sleep_on_head(q, &wait, &flags); |
| 4055 | timeout = schedule_timeout(timeout); | 3782 | timeout = schedule_timeout(timeout); |
| 4056 | SLEEP_ON_TAIL | 3783 | sleep_on_tail(q, &wait, &flags); |
| 4057 | 3784 | ||
| 4058 | return timeout; | 3785 | return timeout; |
| 4059 | } | 3786 | } |
| 4060 | |||
| 4061 | EXPORT_SYMBOL(sleep_on_timeout); | 3787 | EXPORT_SYMBOL(sleep_on_timeout); |
| 4062 | 3788 | ||
| 4063 | #ifdef CONFIG_RT_MUTEXES | 3789 | #ifdef CONFIG_RT_MUTEXES |
| @@ -4074,29 +3800,30 @@ EXPORT_SYMBOL(sleep_on_timeout); | |||
| 4074 | */ | 3800 | */ |
| 4075 | void rt_mutex_setprio(struct task_struct *p, int prio) | 3801 | void rt_mutex_setprio(struct task_struct *p, int prio) |
| 4076 | { | 3802 | { |
| 4077 | struct prio_array *array; | ||
| 4078 | unsigned long flags; | 3803 | unsigned long flags; |
| 3804 | int oldprio, on_rq; | ||
| 4079 | struct rq *rq; | 3805 | struct rq *rq; |
| 4080 | int oldprio; | 3806 | u64 now; |
| 4081 | 3807 | ||
| 4082 | BUG_ON(prio < 0 || prio > MAX_PRIO); | 3808 | BUG_ON(prio < 0 || prio > MAX_PRIO); |
| 4083 | 3809 | ||
| 4084 | rq = task_rq_lock(p, &flags); | 3810 | rq = task_rq_lock(p, &flags); |
| 3811 | now = rq_clock(rq); | ||
| 4085 | 3812 | ||
| 4086 | oldprio = p->prio; | 3813 | oldprio = p->prio; |
| 4087 | array = p->array; | 3814 | on_rq = p->se.on_rq; |
| 4088 | if (array) | 3815 | if (on_rq) |
| 4089 | dequeue_task(p, array); | 3816 | dequeue_task(rq, p, 0, now); |
| 3817 | |||
| 3818 | if (rt_prio(prio)) | ||
| 3819 | p->sched_class = &rt_sched_class; | ||
| 3820 | else | ||
| 3821 | p->sched_class = &fair_sched_class; | ||
| 3822 | |||
| 4090 | p->prio = prio; | 3823 | p->prio = prio; |
| 4091 | 3824 | ||
| 4092 | if (array) { | 3825 | if (on_rq) { |
| 4093 | /* | 3826 | enqueue_task(rq, p, 0, now); |
| 4094 | * If changing to an RT priority then queue it | ||
| 4095 | * in the active array! | ||
| 4096 | */ | ||
| 4097 | if (rt_task(p)) | ||
| 4098 | array = rq->active; | ||
| 4099 | enqueue_task(p, array); | ||
| 4100 | /* | 3827 | /* |
| 4101 | * Reschedule if we are currently running on this runqueue and | 3828 | * Reschedule if we are currently running on this runqueue and |
| 4102 | * our priority decreased, or if we are not currently running on | 3829 | * our priority decreased, or if we are not currently running on |
| @@ -4105,8 +3832,9 @@ void rt_mutex_setprio(struct task_struct *p, int prio) | |||
| 4105 | if (task_running(rq, p)) { | 3832 | if (task_running(rq, p)) { |
| 4106 | if (p->prio > oldprio) | 3833 | if (p->prio > oldprio) |
| 4107 | resched_task(rq->curr); | 3834 | resched_task(rq->curr); |
| 4108 | } else if (TASK_PREEMPTS_CURR(p, rq)) | 3835 | } else { |
| 4109 | resched_task(rq->curr); | 3836 | check_preempt_curr(rq, p); |
| 3837 | } | ||
| 4110 | } | 3838 | } |
| 4111 | task_rq_unlock(rq, &flags); | 3839 | task_rq_unlock(rq, &flags); |
| 4112 | } | 3840 | } |
| @@ -4115,10 +3843,10 @@ void rt_mutex_setprio(struct task_struct *p, int prio) | |||
| 4115 | 3843 | ||
| 4116 | void set_user_nice(struct task_struct *p, long nice) | 3844 | void set_user_nice(struct task_struct *p, long nice) |
| 4117 | { | 3845 | { |
| 4118 | struct prio_array *array; | 3846 | int old_prio, delta, on_rq; |
| 4119 | int old_prio, delta; | ||
| 4120 | unsigned long flags; | 3847 | unsigned long flags; |
| 4121 | struct rq *rq; | 3848 | struct rq *rq; |
| 3849 | u64 now; | ||
| 4122 | 3850 | ||
| 4123 | if (TASK_NICE(p) == nice || nice < -20 || nice > 19) | 3851 | if (TASK_NICE(p) == nice || nice < -20 || nice > 19) |
| 4124 | return; | 3852 | return; |
| @@ -4127,20 +3855,21 @@ void set_user_nice(struct task_struct *p, long nice) | |||
| 4127 | * the task might be in the middle of scheduling on another CPU. | 3855 | * the task might be in the middle of scheduling on another CPU. |
| 4128 | */ | 3856 | */ |
| 4129 | rq = task_rq_lock(p, &flags); | 3857 | rq = task_rq_lock(p, &flags); |
| 3858 | now = rq_clock(rq); | ||
| 4130 | /* | 3859 | /* |
| 4131 | * The RT priorities are set via sched_setscheduler(), but we still | 3860 | * The RT priorities are set via sched_setscheduler(), but we still |
| 4132 | * allow the 'normal' nice value to be set - but as expected | 3861 | * allow the 'normal' nice value to be set - but as expected |
| 4133 | * it wont have any effect on scheduling until the task is | 3862 | * it wont have any effect on scheduling until the task is |
| 4134 | * not SCHED_NORMAL/SCHED_BATCH: | 3863 | * SCHED_FIFO/SCHED_RR: |
| 4135 | */ | 3864 | */ |
| 4136 | if (has_rt_policy(p)) { | 3865 | if (task_has_rt_policy(p)) { |
| 4137 | p->static_prio = NICE_TO_PRIO(nice); | 3866 | p->static_prio = NICE_TO_PRIO(nice); |
| 4138 | goto out_unlock; | 3867 | goto out_unlock; |
| 4139 | } | 3868 | } |
| 4140 | array = p->array; | 3869 | on_rq = p->se.on_rq; |
| 4141 | if (array) { | 3870 | if (on_rq) { |
| 4142 | dequeue_task(p, array); | 3871 | dequeue_task(rq, p, 0, now); |
| 4143 | dec_raw_weighted_load(rq, p); | 3872 | dec_load(rq, p, now); |
| 4144 | } | 3873 | } |
| 4145 | 3874 | ||
| 4146 | p->static_prio = NICE_TO_PRIO(nice); | 3875 | p->static_prio = NICE_TO_PRIO(nice); |
| @@ -4149,9 +3878,9 @@ void set_user_nice(struct task_struct *p, long nice) | |||
| 4149 | p->prio = effective_prio(p); | 3878 | p->prio = effective_prio(p); |
| 4150 | delta = p->prio - old_prio; | 3879 | delta = p->prio - old_prio; |
| 4151 | 3880 | ||
| 4152 | if (array) { | 3881 | if (on_rq) { |
| 4153 | enqueue_task(p, array); | 3882 | enqueue_task(rq, p, 0, now); |
| 4154 | inc_raw_weighted_load(rq, p); | 3883 | inc_load(rq, p, now); |
| 4155 | /* | 3884 | /* |
| 4156 | * If the task increased its priority or is running and | 3885 | * If the task increased its priority or is running and |
| 4157 | * lowered its priority, then reschedule its CPU: | 3886 | * lowered its priority, then reschedule its CPU: |
| @@ -4271,20 +4000,28 @@ static inline struct task_struct *find_process_by_pid(pid_t pid) | |||
| 4271 | } | 4000 | } |
| 4272 | 4001 | ||
| 4273 | /* Actually do priority change: must hold rq lock. */ | 4002 | /* Actually do priority change: must hold rq lock. */ |
| 4274 | static void __setscheduler(struct task_struct *p, int policy, int prio) | 4003 | static void |
| 4004 | __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) | ||
| 4275 | { | 4005 | { |
| 4276 | BUG_ON(p->array); | 4006 | BUG_ON(p->se.on_rq); |
| 4277 | 4007 | ||
| 4278 | p->policy = policy; | 4008 | p->policy = policy; |
| 4009 | switch (p->policy) { | ||
| 4010 | case SCHED_NORMAL: | ||
| 4011 | case SCHED_BATCH: | ||
| 4012 | case SCHED_IDLE: | ||
| 4013 | p->sched_class = &fair_sched_class; | ||
| 4014 | break; | ||
| 4015 | case SCHED_FIFO: | ||
| 4016 | case SCHED_RR: | ||
| 4017 | p->sched_class = &rt_sched_class; | ||
| 4018 | break; | ||
| 4019 | } | ||
| 4020 | |||
| 4279 | p->rt_priority = prio; | 4021 | p->rt_priority = prio; |
| 4280 | p->normal_prio = normal_prio(p); | 4022 | p->normal_prio = normal_prio(p); |
| 4281 | /* we are holding p->pi_lock already */ | 4023 | /* we are holding p->pi_lock already */ |
| 4282 | p->prio = rt_mutex_getprio(p); | 4024 | p->prio = rt_mutex_getprio(p); |
| 4283 | /* | ||
| 4284 | * SCHED_BATCH tasks are treated as perpetual CPU hogs: | ||
| 4285 | */ | ||
| 4286 | if (policy == SCHED_BATCH) | ||
| 4287 | p->sleep_avg = 0; | ||
| 4288 | set_load_weight(p); | 4025 | set_load_weight(p); |
| 4289 | } | 4026 | } |
| 4290 | 4027 | ||
| @@ -4299,8 +4036,7 @@ static void __setscheduler(struct task_struct *p, int policy, int prio) | |||
| 4299 | int sched_setscheduler(struct task_struct *p, int policy, | 4036 | int sched_setscheduler(struct task_struct *p, int policy, |
| 4300 | struct sched_param *param) | 4037 | struct sched_param *param) |
| 4301 | { | 4038 | { |
| 4302 | int retval, oldprio, oldpolicy = -1; | 4039 | int retval, oldprio, oldpolicy = -1, on_rq; |
| 4303 | struct prio_array *array; | ||
| 4304 | unsigned long flags; | 4040 | unsigned long flags; |
| 4305 | struct rq *rq; | 4041 | struct rq *rq; |
| 4306 | 4042 | ||
| @@ -4311,27 +4047,27 @@ recheck: | |||
| 4311 | if (policy < 0) | 4047 | if (policy < 0) |
| 4312 | policy = oldpolicy = p->policy; | 4048 | policy = oldpolicy = p->policy; |
| 4313 | else if (policy != SCHED_FIFO && policy != SCHED_RR && | 4049 | else if (policy != SCHED_FIFO && policy != SCHED_RR && |
| 4314 | policy != SCHED_NORMAL && policy != SCHED_BATCH) | 4050 | policy != SCHED_NORMAL && policy != SCHED_BATCH && |
| 4051 | policy != SCHED_IDLE) | ||
| 4315 | return -EINVAL; | 4052 | return -EINVAL; |
| 4316 | /* | 4053 | /* |
| 4317 | * Valid priorities for SCHED_FIFO and SCHED_RR are | 4054 | * Valid priorities for SCHED_FIFO and SCHED_RR are |
| 4318 | * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL and | 4055 | * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL, |
| 4319 | * SCHED_BATCH is 0. | 4056 | * SCHED_BATCH and SCHED_IDLE is 0. |
| 4320 | */ | 4057 | */ |
| 4321 | if (param->sched_priority < 0 || | 4058 | if (param->sched_priority < 0 || |
| 4322 | (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) || | 4059 | (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) || |
| 4323 | (!p->mm && param->sched_priority > MAX_RT_PRIO-1)) | 4060 | (!p->mm && param->sched_priority > MAX_RT_PRIO-1)) |
| 4324 | return -EINVAL; | 4061 | return -EINVAL; |
| 4325 | if (is_rt_policy(policy) != (param->sched_priority != 0)) | 4062 | if (rt_policy(policy) != (param->sched_priority != 0)) |
| 4326 | return -EINVAL; | 4063 | return -EINVAL; |
| 4327 | 4064 | ||
| 4328 | /* | 4065 | /* |
| 4329 | * Allow unprivileged RT tasks to decrease priority: | 4066 | * Allow unprivileged RT tasks to decrease priority: |
| 4330 | */ | 4067 | */ |
| 4331 | if (!capable(CAP_SYS_NICE)) { | 4068 | if (!capable(CAP_SYS_NICE)) { |
| 4332 | if (is_rt_policy(policy)) { | 4069 | if (rt_policy(policy)) { |
| 4333 | unsigned long rlim_rtprio; | 4070 | unsigned long rlim_rtprio; |
| 4334 | unsigned long flags; | ||
| 4335 | 4071 | ||
| 4336 | if (!lock_task_sighand(p, &flags)) | 4072 | if (!lock_task_sighand(p, &flags)) |
| 4337 | return -ESRCH; | 4073 | return -ESRCH; |
| @@ -4347,6 +4083,12 @@ recheck: | |||
| 4347 | param->sched_priority > rlim_rtprio) | 4083 | param->sched_priority > rlim_rtprio) |
| 4348 | return -EPERM; | 4084 | return -EPERM; |
| 4349 | } | 4085 | } |
| 4086 | /* | ||
| 4087 | * Like positive nice levels, dont allow tasks to | ||
| 4088 | * move out of SCHED_IDLE either: | ||
| 4089 | */ | ||
| 4090 | if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) | ||
| 4091 | return -EPERM; | ||
| 4350 | 4092 | ||
| 4351 | /* can't change other user's priorities */ | 4093 | /* can't change other user's priorities */ |
| 4352 | if ((current->euid != p->euid) && | 4094 | if ((current->euid != p->euid) && |
| @@ -4374,13 +4116,13 @@ recheck: | |||
| 4374 | spin_unlock_irqrestore(&p->pi_lock, flags); | 4116 | spin_unlock_irqrestore(&p->pi_lock, flags); |
| 4375 | goto recheck; | 4117 | goto recheck; |
| 4376 | } | 4118 | } |
| 4377 | array = p->array; | 4119 | on_rq = p->se.on_rq; |
| 4378 | if (array) | 4120 | if (on_rq) |
| 4379 | deactivate_task(p, rq); | 4121 | deactivate_task(rq, p, 0); |
| 4380 | oldprio = p->prio; | 4122 | oldprio = p->prio; |
| 4381 | __setscheduler(p, policy, param->sched_priority); | 4123 | __setscheduler(rq, p, policy, param->sched_priority); |
| 4382 | if (array) { | 4124 | if (on_rq) { |
| 4383 | __activate_task(p, rq); | 4125 | activate_task(rq, p, 0); |
| 4384 | /* | 4126 | /* |
| 4385 | * Reschedule if we are currently running on this runqueue and | 4127 | * Reschedule if we are currently running on this runqueue and |
| 4386 | * our priority decreased, or if we are not currently running on | 4128 | * our priority decreased, or if we are not currently running on |
| @@ -4389,8 +4131,9 @@ recheck: | |||
| 4389 | if (task_running(rq, p)) { | 4131 | if (task_running(rq, p)) { |
| 4390 | if (p->prio > oldprio) | 4132 | if (p->prio > oldprio) |
| 4391 | resched_task(rq->curr); | 4133 | resched_task(rq->curr); |
| 4392 | } else if (TASK_PREEMPTS_CURR(p, rq)) | 4134 | } else { |
| 4393 | resched_task(rq->curr); | 4135 | check_preempt_curr(rq, p); |
| 4136 | } | ||
| 4394 | } | 4137 | } |
| 4395 | __task_rq_unlock(rq); | 4138 | __task_rq_unlock(rq); |
| 4396 | spin_unlock_irqrestore(&p->pi_lock, flags); | 4139 | spin_unlock_irqrestore(&p->pi_lock, flags); |
| @@ -4662,41 +4405,18 @@ asmlinkage long sys_sched_getaffinity(pid_t pid, unsigned int len, | |||
| 4662 | /** | 4405 | /** |
| 4663 | * sys_sched_yield - yield the current processor to other threads. | 4406 | * sys_sched_yield - yield the current processor to other threads. |
| 4664 | * | 4407 | * |
| 4665 | * This function yields the current CPU by moving the calling thread | 4408 | * This function yields the current CPU to other tasks. If there are no |
| 4666 | * to the expired array. If there are no other threads running on this | 4409 | * other threads running on this CPU then this function will return. |
| 4667 | * CPU then this function will return. | ||
| 4668 | */ | 4410 | */ |
| 4669 | asmlinkage long sys_sched_yield(void) | 4411 | asmlinkage long sys_sched_yield(void) |
| 4670 | { | 4412 | { |
| 4671 | struct rq *rq = this_rq_lock(); | 4413 | struct rq *rq = this_rq_lock(); |
| 4672 | struct prio_array *array = current->array, *target = rq->expired; | ||
| 4673 | 4414 | ||
| 4674 | schedstat_inc(rq, yld_cnt); | 4415 | schedstat_inc(rq, yld_cnt); |
| 4675 | /* | 4416 | if (unlikely(rq->nr_running == 1)) |
| 4676 | * We implement yielding by moving the task into the expired | ||
| 4677 | * queue. | ||
| 4678 | * | ||
| 4679 | * (special rule: RT tasks will just roundrobin in the active | ||
| 4680 | * array.) | ||
| 4681 | */ | ||
| 4682 | if (rt_task(current)) | ||
| 4683 | target = rq->active; | ||
| 4684 | |||
| 4685 | if (array->nr_active == 1) { | ||
| 4686 | schedstat_inc(rq, yld_act_empty); | 4417 | schedstat_inc(rq, yld_act_empty); |
| 4687 | if (!rq->expired->nr_active) | 4418 | else |
| 4688 | schedstat_inc(rq, yld_both_empty); | 4419 | current->sched_class->yield_task(rq, current); |
| 4689 | } else if (!rq->expired->nr_active) | ||
| 4690 | schedstat_inc(rq, yld_exp_empty); | ||
| 4691 | |||
| 4692 | if (array != target) { | ||
| 4693 | dequeue_task(current, array); | ||
| 4694 | enqueue_task(current, target); | ||
| 4695 | } else | ||
| 4696 | /* | ||
| 4697 | * requeue_task is cheaper so perform that if possible. | ||
| 4698 | */ | ||
| 4699 | requeue_task(current, array); | ||
| 4700 | 4420 | ||
| 4701 | /* | 4421 | /* |
| 4702 | * Since we are going to call schedule() anyway, there's | 4422 | * Since we are going to call schedule() anyway, there's |
| @@ -4847,6 +4567,7 @@ asmlinkage long sys_sched_get_priority_max(int policy) | |||
| 4847 | break; | 4567 | break; |
| 4848 | case SCHED_NORMAL: | 4568 | case SCHED_NORMAL: |
| 4849 | case SCHED_BATCH: | 4569 | case SCHED_BATCH: |
| 4570 | case SCHED_IDLE: | ||
| 4850 | ret = 0; | 4571 | ret = 0; |
| 4851 | break; | 4572 | break; |
| 4852 | } | 4573 | } |
| @@ -4871,6 +4592,7 @@ asmlinkage long sys_sched_get_priority_min(int policy) | |||
| 4871 | break; | 4592 | break; |
| 4872 | case SCHED_NORMAL: | 4593 | case SCHED_NORMAL: |
| 4873 | case SCHED_BATCH: | 4594 | case SCHED_BATCH: |
| 4595 | case SCHED_IDLE: | ||
| 4874 | ret = 0; | 4596 | ret = 0; |
| 4875 | } | 4597 | } |
| 4876 | return ret; | 4598 | return ret; |
| @@ -4905,7 +4627,7 @@ long sys_sched_rr_get_interval(pid_t pid, struct timespec __user *interval) | |||
| 4905 | goto out_unlock; | 4627 | goto out_unlock; |
| 4906 | 4628 | ||
| 4907 | jiffies_to_timespec(p->policy == SCHED_FIFO ? | 4629 | jiffies_to_timespec(p->policy == SCHED_FIFO ? |
| 4908 | 0 : task_timeslice(p), &t); | 4630 | 0 : static_prio_timeslice(p->static_prio), &t); |
| 4909 | read_unlock(&tasklist_lock); | 4631 | read_unlock(&tasklist_lock); |
| 4910 | retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0; | 4632 | retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0; |
| 4911 | out_nounlock: | 4633 | out_nounlock: |
| @@ -4925,14 +4647,14 @@ static void show_task(struct task_struct *p) | |||
| 4925 | state = p->state ? __ffs(p->state) + 1 : 0; | 4647 | state = p->state ? __ffs(p->state) + 1 : 0; |
| 4926 | printk("%-13.13s %c", p->comm, | 4648 | printk("%-13.13s %c", p->comm, |
| 4927 | state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); | 4649 | state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); |
| 4928 | #if (BITS_PER_LONG == 32) | 4650 | #if BITS_PER_LONG == 32 |
| 4929 | if (state == TASK_RUNNING) | 4651 | if (state == TASK_RUNNING) |
| 4930 | printk(" running "); | 4652 | printk(" running "); |
| 4931 | else | 4653 | else |
| 4932 | printk(" %08lX ", thread_saved_pc(p)); | 4654 | printk(" %08lx ", thread_saved_pc(p)); |
| 4933 | #else | 4655 | #else |
| 4934 | if (state == TASK_RUNNING) | 4656 | if (state == TASK_RUNNING) |
| 4935 | printk(" running task "); | 4657 | printk(" running task "); |
| 4936 | else | 4658 | else |
| 4937 | printk(" %016lx ", thread_saved_pc(p)); | 4659 | printk(" %016lx ", thread_saved_pc(p)); |
| 4938 | #endif | 4660 | #endif |
| @@ -4944,11 +4666,7 @@ static void show_task(struct task_struct *p) | |||
| 4944 | free = (unsigned long)n - (unsigned long)end_of_stack(p); | 4666 | free = (unsigned long)n - (unsigned long)end_of_stack(p); |
| 4945 | } | 4667 | } |
| 4946 | #endif | 4668 | #endif |
| 4947 | printk("%5lu %5d %6d", free, p->pid, p->parent->pid); | 4669 | printk("%5lu %5d %6d\n", free, p->pid, p->parent->pid); |
| 4948 | if (!p->mm) | ||
| 4949 | printk(" (L-TLB)\n"); | ||
| 4950 | else | ||
| 4951 | printk(" (NOTLB)\n"); | ||
| 4952 | 4670 | ||
| 4953 | if (state != TASK_RUNNING) | 4671 | if (state != TASK_RUNNING) |
| 4954 | show_stack(p, NULL); | 4672 | show_stack(p, NULL); |
| @@ -4958,14 +4676,12 @@ void show_state_filter(unsigned long state_filter) | |||
| 4958 | { | 4676 | { |
| 4959 | struct task_struct *g, *p; | 4677 | struct task_struct *g, *p; |
| 4960 | 4678 | ||
| 4961 | #if (BITS_PER_LONG == 32) | 4679 | #if BITS_PER_LONG == 32 |
| 4962 | printk("\n" | 4680 | printk(KERN_INFO |
| 4963 | " free sibling\n"); | 4681 | " task PC stack pid father\n"); |
| 4964 | printk(" task PC stack pid father child younger older\n"); | ||
| 4965 | #else | 4682 | #else |
| 4966 | printk("\n" | 4683 | printk(KERN_INFO |
| 4967 | " free sibling\n"); | 4684 | " task PC stack pid father\n"); |
| 4968 | printk(" task PC stack pid father child younger older\n"); | ||
| 4969 | #endif | 4685 | #endif |
| 4970 | read_lock(&tasklist_lock); | 4686 | read_lock(&tasklist_lock); |
| 4971 | do_each_thread(g, p) { | 4687 | do_each_thread(g, p) { |
| @@ -4980,6 +4696,9 @@ void show_state_filter(unsigned long state_filter) | |||
| 4980 | 4696 | ||
| 4981 | touch_all_softlockup_watchdogs(); | 4697 | touch_all_softlockup_watchdogs(); |
| 4982 | 4698 | ||
| 4699 | #ifdef CONFIG_SCHED_DEBUG | ||
| 4700 | sysrq_sched_debug_show(); | ||
| 4701 | #endif | ||
| 4983 | read_unlock(&tasklist_lock); | 4702 | read_unlock(&tasklist_lock); |
| 4984 | /* | 4703 | /* |
| 4985 | * Only show locks if all tasks are dumped: | 4704 | * Only show locks if all tasks are dumped: |
| @@ -4988,6 +4707,11 @@ void show_state_filter(unsigned long state_filter) | |||
| 4988 | debug_show_all_locks(); | 4707 | debug_show_all_locks(); |
| 4989 | } | 4708 | } |
| 4990 | 4709 | ||
| 4710 | void __cpuinit init_idle_bootup_task(struct task_struct *idle) | ||
| 4711 | { | ||
| 4712 | idle->sched_class = &idle_sched_class; | ||
| 4713 | } | ||
| 4714 | |||
| 4991 | /** | 4715 | /** |
| 4992 | * init_idle - set up an idle thread for a given CPU | 4716 | * init_idle - set up an idle thread for a given CPU |
| 4993 | * @idle: task in question | 4717 | * @idle: task in question |
| @@ -5001,13 +4725,12 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) | |||
| 5001 | struct rq *rq = cpu_rq(cpu); | 4725 | struct rq *rq = cpu_rq(cpu); |
| 5002 | unsigned long flags; | 4726 | unsigned long flags; |
| 5003 | 4727 | ||
| 5004 | idle->timestamp = sched_clock(); | 4728 | __sched_fork(idle); |
| 5005 | idle->sleep_avg = 0; | 4729 | idle->se.exec_start = sched_clock(); |
| 5006 | idle->array = NULL; | 4730 | |
| 5007 | idle->prio = idle->normal_prio = MAX_PRIO; | 4731 | idle->prio = idle->normal_prio = MAX_PRIO; |
| 5008 | idle->state = TASK_RUNNING; | ||
| 5009 | idle->cpus_allowed = cpumask_of_cpu(cpu); | 4732 | idle->cpus_allowed = cpumask_of_cpu(cpu); |
| 5010 | set_task_cpu(idle, cpu); | 4733 | __set_task_cpu(idle, cpu); |
| 5011 | 4734 | ||
| 5012 | spin_lock_irqsave(&rq->lock, flags); | 4735 | spin_lock_irqsave(&rq->lock, flags); |
| 5013 | rq->curr = rq->idle = idle; | 4736 | rq->curr = rq->idle = idle; |
| @@ -5022,6 +4745,10 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) | |||
| 5022 | #else | 4745 | #else |
| 5023 | task_thread_info(idle)->preempt_count = 0; | 4746 | task_thread_info(idle)->preempt_count = 0; |
| 5024 | #endif | 4747 | #endif |
| 4748 | /* | ||
| 4749 | * The idle tasks have their own, simple scheduling class: | ||
| 4750 | */ | ||
| 4751 | idle->sched_class = &idle_sched_class; | ||
| 5025 | } | 4752 | } |
| 5026 | 4753 | ||
| 5027 | /* | 4754 | /* |
| @@ -5033,6 +4760,28 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) | |||
| 5033 | */ | 4760 | */ |
| 5034 | cpumask_t nohz_cpu_mask = CPU_MASK_NONE; | 4761 | cpumask_t nohz_cpu_mask = CPU_MASK_NONE; |
| 5035 | 4762 | ||
| 4763 | /* | ||
| 4764 | * Increase the granularity value when there are more CPUs, | ||
| 4765 | * because with more CPUs the 'effective latency' as visible | ||
| 4766 | * to users decreases. But the relationship is not linear, | ||
| 4767 | * so pick a second-best guess by going with the log2 of the | ||
| 4768 | * number of CPUs. | ||
| 4769 | * | ||
| 4770 | * This idea comes from the SD scheduler of Con Kolivas: | ||
| 4771 | */ | ||
| 4772 | static inline void sched_init_granularity(void) | ||
| 4773 | { | ||
| 4774 | unsigned int factor = 1 + ilog2(num_online_cpus()); | ||
| 4775 | const unsigned long gran_limit = 100000000; | ||
| 4776 | |||
| 4777 | sysctl_sched_granularity *= factor; | ||
| 4778 | if (sysctl_sched_granularity > gran_limit) | ||
| 4779 | sysctl_sched_granularity = gran_limit; | ||
| 4780 | |||
| 4781 | sysctl_sched_runtime_limit = sysctl_sched_granularity * 4; | ||
| 4782 | sysctl_sched_wakeup_granularity = sysctl_sched_granularity / 2; | ||
| 4783 | } | ||
| 4784 | |||
| 5036 | #ifdef CONFIG_SMP | 4785 | #ifdef CONFIG_SMP |
| 5037 | /* | 4786 | /* |
| 5038 | * This is how migration works: | 4787 | * This is how migration works: |
| @@ -5106,7 +4855,7 @@ EXPORT_SYMBOL_GPL(set_cpus_allowed); | |||
| 5106 | static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) | 4855 | static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) |
| 5107 | { | 4856 | { |
| 5108 | struct rq *rq_dest, *rq_src; | 4857 | struct rq *rq_dest, *rq_src; |
| 5109 | int ret = 0; | 4858 | int ret = 0, on_rq; |
| 5110 | 4859 | ||
| 5111 | if (unlikely(cpu_is_offline(dest_cpu))) | 4860 | if (unlikely(cpu_is_offline(dest_cpu))) |
| 5112 | return ret; | 4861 | return ret; |
| @@ -5122,20 +4871,13 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) | |||
| 5122 | if (!cpu_isset(dest_cpu, p->cpus_allowed)) | 4871 | if (!cpu_isset(dest_cpu, p->cpus_allowed)) |
| 5123 | goto out; | 4872 | goto out; |
| 5124 | 4873 | ||
| 4874 | on_rq = p->se.on_rq; | ||
| 4875 | if (on_rq) | ||
| 4876 | deactivate_task(rq_src, p, 0); | ||
| 5125 | set_task_cpu(p, dest_cpu); | 4877 | set_task_cpu(p, dest_cpu); |
| 5126 | if (p->array) { | 4878 | if (on_rq) { |
| 5127 | /* | 4879 | activate_task(rq_dest, p, 0); |
| 5128 | * Sync timestamp with rq_dest's before activating. | 4880 | check_preempt_curr(rq_dest, p); |
| 5129 | * The same thing could be achieved by doing this step | ||
| 5130 | * afterwards, and pretending it was a local activate. | ||
| 5131 | * This way is cleaner and logically correct. | ||
| 5132 | */ | ||
| 5133 | p->timestamp = p->timestamp - rq_src->most_recent_timestamp | ||
| 5134 | + rq_dest->most_recent_timestamp; | ||
| 5135 | deactivate_task(p, rq_src); | ||
| 5136 | __activate_task(p, rq_dest); | ||
| 5137 | if (TASK_PREEMPTS_CURR(p, rq_dest)) | ||
| 5138 | resched_task(rq_dest->curr); | ||
| 5139 | } | 4881 | } |
| 5140 | ret = 1; | 4882 | ret = 1; |
| 5141 | out: | 4883 | out: |
| @@ -5287,7 +5029,8 @@ static void migrate_live_tasks(int src_cpu) | |||
| 5287 | write_unlock_irq(&tasklist_lock); | 5029 | write_unlock_irq(&tasklist_lock); |
| 5288 | } | 5030 | } |
| 5289 | 5031 | ||
| 5290 | /* Schedules idle task to be the next runnable task on current CPU. | 5032 | /* |
| 5033 | * Schedules idle task to be the next runnable task on current CPU. | ||
| 5291 | * It does so by boosting its priority to highest possible and adding it to | 5034 | * It does so by boosting its priority to highest possible and adding it to |
| 5292 | * the _front_ of the runqueue. Used by CPU offline code. | 5035 | * the _front_ of the runqueue. Used by CPU offline code. |
| 5293 | */ | 5036 | */ |
| @@ -5307,10 +5050,10 @@ void sched_idle_next(void) | |||
| 5307 | */ | 5050 | */ |
| 5308 | spin_lock_irqsave(&rq->lock, flags); | 5051 | spin_lock_irqsave(&rq->lock, flags); |
| 5309 | 5052 | ||
| 5310 | __setscheduler(p, SCHED_FIFO, MAX_RT_PRIO-1); | 5053 | __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1); |
| 5311 | 5054 | ||
| 5312 | /* Add idle task to the _front_ of its priority queue: */ | 5055 | /* Add idle task to the _front_ of its priority queue: */ |
| 5313 | __activate_idle_task(p, rq); | 5056 | activate_idle_task(p, rq); |
| 5314 | 5057 | ||
| 5315 | spin_unlock_irqrestore(&rq->lock, flags); | 5058 | spin_unlock_irqrestore(&rq->lock, flags); |
| 5316 | } | 5059 | } |
| @@ -5360,16 +5103,15 @@ static void migrate_dead(unsigned int dead_cpu, struct task_struct *p) | |||
| 5360 | static void migrate_dead_tasks(unsigned int dead_cpu) | 5103 | static void migrate_dead_tasks(unsigned int dead_cpu) |
| 5361 | { | 5104 | { |
| 5362 | struct rq *rq = cpu_rq(dead_cpu); | 5105 | struct rq *rq = cpu_rq(dead_cpu); |
| 5363 | unsigned int arr, i; | 5106 | struct task_struct *next; |
| 5364 | 5107 | ||
| 5365 | for (arr = 0; arr < 2; arr++) { | 5108 | for ( ; ; ) { |
| 5366 | for (i = 0; i < MAX_PRIO; i++) { | 5109 | if (!rq->nr_running) |
| 5367 | struct list_head *list = &rq->arrays[arr].queue[i]; | 5110 | break; |
| 5368 | 5111 | next = pick_next_task(rq, rq->curr, rq_clock(rq)); | |
| 5369 | while (!list_empty(list)) | 5112 | if (!next) |
| 5370 | migrate_dead(dead_cpu, list_entry(list->next, | 5113 | break; |
| 5371 | struct task_struct, run_list)); | 5114 | migrate_dead(dead_cpu, next); |
| 5372 | } | ||
| 5373 | } | 5115 | } |
| 5374 | } | 5116 | } |
| 5375 | #endif /* CONFIG_HOTPLUG_CPU */ | 5117 | #endif /* CONFIG_HOTPLUG_CPU */ |
| @@ -5393,14 +5135,14 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) | |||
| 5393 | 5135 | ||
| 5394 | case CPU_UP_PREPARE: | 5136 | case CPU_UP_PREPARE: |
| 5395 | case CPU_UP_PREPARE_FROZEN: | 5137 | case CPU_UP_PREPARE_FROZEN: |
| 5396 | p = kthread_create(migration_thread, hcpu, "migration/%d",cpu); | 5138 | p = kthread_create(migration_thread, hcpu, "migration/%d", cpu); |
| 5397 | if (IS_ERR(p)) | 5139 | if (IS_ERR(p)) |
| 5398 | return NOTIFY_BAD; | 5140 | return NOTIFY_BAD; |
| 5399 | p->flags |= PF_NOFREEZE; | 5141 | p->flags |= PF_NOFREEZE; |
| 5400 | kthread_bind(p, cpu); | 5142 | kthread_bind(p, cpu); |
| 5401 | /* Must be high prio: stop_machine expects to yield to it. */ | 5143 | /* Must be high prio: stop_machine expects to yield to it. */ |
| 5402 | rq = task_rq_lock(p, &flags); | 5144 | rq = task_rq_lock(p, &flags); |
| 5403 | __setscheduler(p, SCHED_FIFO, MAX_RT_PRIO-1); | 5145 | __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1); |
| 5404 | task_rq_unlock(rq, &flags); | 5146 | task_rq_unlock(rq, &flags); |
| 5405 | cpu_rq(cpu)->migration_thread = p; | 5147 | cpu_rq(cpu)->migration_thread = p; |
| 5406 | break; | 5148 | break; |
| @@ -5431,9 +5173,10 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) | |||
| 5431 | rq->migration_thread = NULL; | 5173 | rq->migration_thread = NULL; |
| 5432 | /* Idle task back to normal (off runqueue, low prio) */ | 5174 | /* Idle task back to normal (off runqueue, low prio) */ |
| 5433 | rq = task_rq_lock(rq->idle, &flags); | 5175 | rq = task_rq_lock(rq->idle, &flags); |
| 5434 | deactivate_task(rq->idle, rq); | 5176 | deactivate_task(rq, rq->idle, 0); |
| 5435 | rq->idle->static_prio = MAX_PRIO; | 5177 | rq->idle->static_prio = MAX_PRIO; |
| 5436 | __setscheduler(rq->idle, SCHED_NORMAL, 0); | 5178 | __setscheduler(rq, rq->idle, SCHED_NORMAL, 0); |
| 5179 | rq->idle->sched_class = &idle_sched_class; | ||
| 5437 | migrate_dead_tasks(cpu); | 5180 | migrate_dead_tasks(cpu); |
| 5438 | task_rq_unlock(rq, &flags); | 5181 | task_rq_unlock(rq, &flags); |
| 5439 | migrate_nr_uninterruptible(rq); | 5182 | migrate_nr_uninterruptible(rq); |
| @@ -5742,483 +5485,6 @@ init_sched_build_groups(cpumask_t span, const cpumask_t *cpu_map, | |||
| 5742 | 5485 | ||
| 5743 | #define SD_NODES_PER_DOMAIN 16 | 5486 | #define SD_NODES_PER_DOMAIN 16 |
| 5744 | 5487 | ||
| 5745 | /* | ||
| 5746 | * Self-tuning task migration cost measurement between source and target CPUs. | ||
| 5747 | * | ||
| 5748 | * This is done by measuring the cost of manipulating buffers of varying | ||
| 5749 | * sizes. For a given buffer-size here are the steps that are taken: | ||
| 5750 | * | ||
| 5751 | * 1) the source CPU reads+dirties a shared buffer | ||
| 5752 | * 2) the target CPU reads+dirties the same shared buffer | ||
| 5753 | * | ||
| 5754 | * We measure how long they take, in the following 4 scenarios: | ||
| 5755 | * | ||
| 5756 | * - source: CPU1, target: CPU2 | cost1 | ||
| 5757 | * - source: CPU2, target: CPU1 | cost2 | ||
| 5758 | * - source: CPU1, target: CPU1 | cost3 | ||
| 5759 | * - source: CPU2, target: CPU2 | cost4 | ||
| 5760 | * | ||
| 5761 | * We then calculate the cost3+cost4-cost1-cost2 difference - this is | ||
| 5762 | * the cost of migration. | ||
| 5763 | * | ||
| 5764 | * We then start off from a small buffer-size and iterate up to larger | ||
| 5765 | * buffer sizes, in 5% steps - measuring each buffer-size separately, and | ||
| 5766 | * doing a maximum search for the cost. (The maximum cost for a migration | ||
| 5767 | * normally occurs when the working set size is around the effective cache | ||
| 5768 | * size.) | ||
| 5769 | */ | ||
| 5770 | #define SEARCH_SCOPE 2 | ||
| 5771 | #define MIN_CACHE_SIZE (64*1024U) | ||
| 5772 | #define DEFAULT_CACHE_SIZE (5*1024*1024U) | ||
| 5773 | #define ITERATIONS 1 | ||
| 5774 | #define SIZE_THRESH 130 | ||
| 5775 | #define COST_THRESH 130 | ||
| 5776 | |||
| 5777 | /* | ||
| 5778 | * The migration cost is a function of 'domain distance'. Domain | ||
| 5779 | * distance is the number of steps a CPU has to iterate down its | ||
| 5780 | * domain tree to share a domain with the other CPU. The farther | ||
| 5781 | * two CPUs are from each other, the larger the distance gets. | ||
| 5782 | * | ||
| 5783 | * Note that we use the distance only to cache measurement results, | ||
| 5784 | * the distance value is not used numerically otherwise. When two | ||
| 5785 | * CPUs have the same distance it is assumed that the migration | ||
| 5786 | * cost is the same. (this is a simplification but quite practical) | ||
| 5787 | */ | ||
| 5788 | #define MAX_DOMAIN_DISTANCE 32 | ||
| 5789 | |||
| 5790 | static unsigned long long migration_cost[MAX_DOMAIN_DISTANCE] = | ||
| 5791 | { [ 0 ... MAX_DOMAIN_DISTANCE-1 ] = | ||
| 5792 | /* | ||
| 5793 | * Architectures may override the migration cost and thus avoid | ||
| 5794 | * boot-time calibration. Unit is nanoseconds. Mostly useful for | ||
| 5795 | * virtualized hardware: | ||
| 5796 | */ | ||
| 5797 | #ifdef CONFIG_DEFAULT_MIGRATION_COST | ||
| 5798 | CONFIG_DEFAULT_MIGRATION_COST | ||
| 5799 | #else | ||
| 5800 | -1LL | ||
| 5801 | #endif | ||
| 5802 | }; | ||
| 5803 | |||
| 5804 | /* | ||
| 5805 | * Allow override of migration cost - in units of microseconds. | ||
| 5806 | * E.g. migration_cost=1000,2000,3000 will set up a level-1 cost | ||
| 5807 | * of 1 msec, level-2 cost of 2 msecs and level3 cost of 3 msecs: | ||
| 5808 | */ | ||
| 5809 | static int __init migration_cost_setup(char *str) | ||
| 5810 | { | ||
| 5811 | int ints[MAX_DOMAIN_DISTANCE+1], i; | ||
| 5812 | |||
| 5813 | str = get_options(str, ARRAY_SIZE(ints), ints); | ||
| 5814 | |||
| 5815 | printk("#ints: %d\n", ints[0]); | ||
| 5816 | for (i = 1; i <= ints[0]; i++) { | ||
| 5817 | migration_cost[i-1] = (unsigned long long)ints[i]*1000; | ||
| 5818 | printk("migration_cost[%d]: %Ld\n", i-1, migration_cost[i-1]); | ||
| 5819 | } | ||
| 5820 | return 1; | ||
| 5821 | } | ||
| 5822 | |||
| 5823 | __setup ("migration_cost=", migration_cost_setup); | ||
| 5824 | |||
| 5825 | /* | ||
| 5826 | * Global multiplier (divisor) for migration-cutoff values, | ||
| 5827 | * in percentiles. E.g. use a value of 150 to get 1.5 times | ||
| 5828 | * longer cache-hot cutoff times. | ||
| 5829 | * | ||
| 5830 | * (We scale it from 100 to 128 to long long handling easier.) | ||
| 5831 | */ | ||
| 5832 | |||
| 5833 | #define MIGRATION_FACTOR_SCALE 128 | ||
| 5834 | |||
| 5835 | static unsigned int migration_factor = MIGRATION_FACTOR_SCALE; | ||
| 5836 | |||
| 5837 | static int __init setup_migration_factor(char *str) | ||
| 5838 | { | ||
| 5839 | get_option(&str, &migration_factor); | ||
| 5840 | migration_factor = migration_factor * MIGRATION_FACTOR_SCALE / 100; | ||
| 5841 | return 1; | ||
| 5842 | } | ||
| 5843 | |||
| 5844 | __setup("migration_factor=", setup_migration_factor); | ||
| 5845 | |||
| 5846 | /* | ||
| 5847 | * Estimated distance of two CPUs, measured via the number of domains | ||
| 5848 | * we have to pass for the two CPUs to be in the same span: | ||
| 5849 | */ | ||
| 5850 | static unsigned long domain_distance(int cpu1, int cpu2) | ||
| 5851 | { | ||
| 5852 | unsigned long distance = 0; | ||
| 5853 | struct sched_domain *sd; | ||
| 5854 | |||
| 5855 | for_each_domain(cpu1, sd) { | ||
| 5856 | WARN_ON(!cpu_isset(cpu1, sd->span)); | ||
| 5857 | if (cpu_isset(cpu2, sd->span)) | ||
| 5858 | return distance; | ||
| 5859 | distance++; | ||
| 5860 | } | ||
| 5861 | if (distance >= MAX_DOMAIN_DISTANCE) { | ||
| 5862 | WARN_ON(1); | ||
| 5863 | distance = MAX_DOMAIN_DISTANCE-1; | ||
| 5864 | } | ||
| 5865 | |||
| 5866 | return distance; | ||
| 5867 | } | ||
| 5868 | |||
| 5869 | static unsigned int migration_debug; | ||
| 5870 | |||
| 5871 | static int __init setup_migration_debug(char *str) | ||
| 5872 | { | ||
| 5873 | get_option(&str, &migration_debug); | ||
| 5874 | return 1; | ||
| 5875 | } | ||
| 5876 | |||
| 5877 | __setup("migration_debug=", setup_migration_debug); | ||
| 5878 | |||
| 5879 | /* | ||
| 5880 | * Maximum cache-size that the scheduler should try to measure. | ||
| 5881 | * Architectures with larger caches should tune this up during | ||
| 5882 | * bootup. Gets used in the domain-setup code (i.e. during SMP | ||
| 5883 | * bootup). | ||
| 5884 | */ | ||
| 5885 | unsigned int max_cache_size; | ||
| 5886 | |||
| 5887 | static int __init setup_max_cache_size(char *str) | ||
| 5888 | { | ||
| 5889 | get_option(&str, &max_cache_size); | ||
| 5890 | return 1; | ||
| 5891 | } | ||
| 5892 | |||
| 5893 | __setup("max_cache_size=", setup_max_cache_size); | ||
| 5894 | |||
| 5895 | /* | ||
| 5896 | * Dirty a big buffer in a hard-to-predict (for the L2 cache) way. This | ||
| 5897 | * is the operation that is timed, so we try to generate unpredictable | ||
| 5898 | * cachemisses that still end up filling the L2 cache: | ||
| 5899 | */ | ||
| 5900 | static void touch_cache(void *__cache, unsigned long __size) | ||
| 5901 | { | ||
| 5902 | unsigned long size = __size / sizeof(long); | ||
| 5903 | unsigned long chunk1 = size / 3; | ||
| 5904 | unsigned long chunk2 = 2 * size / 3; | ||
| 5905 | unsigned long *cache = __cache; | ||
| 5906 | int i; | ||
| 5907 | |||
| 5908 | for (i = 0; i < size/6; i += 8) { | ||
| 5909 | switch (i % 6) { | ||
| 5910 | case 0: cache[i]++; | ||
| 5911 | case 1: cache[size-1-i]++; | ||
| 5912 | case 2: cache[chunk1-i]++; | ||
| 5913 | case 3: cache[chunk1+i]++; | ||
| 5914 | case 4: cache[chunk2-i]++; | ||
| 5915 | case 5: cache[chunk2+i]++; | ||
| 5916 | } | ||
| 5917 | } | ||
| 5918 | } | ||
| 5919 | |||
| 5920 | /* | ||
| 5921 | * Measure the cache-cost of one task migration. Returns in units of nsec. | ||
| 5922 | */ | ||
| 5923 | static unsigned long long | ||
| 5924 | measure_one(void *cache, unsigned long size, int source, int target) | ||
| 5925 | { | ||
| 5926 | cpumask_t mask, saved_mask; | ||
| 5927 | unsigned long long t0, t1, t2, t3, cost; | ||
| 5928 | |||
| 5929 | saved_mask = current->cpus_allowed; | ||
| 5930 | |||
| 5931 | /* | ||
| 5932 | * Flush source caches to RAM and invalidate them: | ||
| 5933 | */ | ||
| 5934 | sched_cacheflush(); | ||
| 5935 | |||
| 5936 | /* | ||
| 5937 | * Migrate to the source CPU: | ||
| 5938 | */ | ||
| 5939 | mask = cpumask_of_cpu(source); | ||
| 5940 | set_cpus_allowed(current, mask); | ||
| 5941 | WARN_ON(smp_processor_id() != source); | ||
| 5942 | |||
| 5943 | /* | ||
| 5944 | * Dirty the working set: | ||
| 5945 | */ | ||
| 5946 | t0 = sched_clock(); | ||
| 5947 | touch_cache(cache, size); | ||
| 5948 | t1 = sched_clock(); | ||
| 5949 | |||
| 5950 | /* | ||
| 5951 | * Migrate to the target CPU, dirty the L2 cache and access | ||
| 5952 | * the shared buffer. (which represents the working set | ||
| 5953 | * of a migrated task.) | ||
| 5954 | */ | ||
| 5955 | mask = cpumask_of_cpu(target); | ||
| 5956 | set_cpus_allowed(current, mask); | ||
| 5957 | WARN_ON(smp_processor_id() != target); | ||
| 5958 | |||
| 5959 | t2 = sched_clock(); | ||
| 5960 | touch_cache(cache, size); | ||
| 5961 | t3 = sched_clock(); | ||
| 5962 | |||
| 5963 | cost = t1-t0 + t3-t2; | ||
| 5964 | |||
| 5965 | if (migration_debug >= 2) | ||
| 5966 | printk("[%d->%d]: %8Ld %8Ld %8Ld => %10Ld.\n", | ||
| 5967 | source, target, t1-t0, t1-t0, t3-t2, cost); | ||
| 5968 | /* | ||
| 5969 | * Flush target caches to RAM and invalidate them: | ||
| 5970 | */ | ||
| 5971 | sched_cacheflush(); | ||
| 5972 | |||
| 5973 | set_cpus_allowed(current, saved_mask); | ||
| 5974 | |||
| 5975 | return cost; | ||
| 5976 | } | ||
| 5977 | |||
| 5978 | /* | ||
| 5979 | * Measure a series of task migrations and return the average | ||
| 5980 | * result. Since this code runs early during bootup the system | ||
| 5981 | * is 'undisturbed' and the average latency makes sense. | ||
| 5982 | * | ||
| 5983 | * The algorithm in essence auto-detects the relevant cache-size, | ||
| 5984 | * so it will properly detect different cachesizes for different | ||
| 5985 | * cache-hierarchies, depending on how the CPUs are connected. | ||
| 5986 | * | ||
| 5987 | * Architectures can prime the upper limit of the search range via | ||
| 5988 | * max_cache_size, otherwise the search range defaults to 20MB...64K. | ||
| 5989 | */ | ||
| 5990 | static unsigned long long | ||
| 5991 | measure_cost(int cpu1, int cpu2, void *cache, unsigned int size) | ||
| 5992 | { | ||
| 5993 | unsigned long long cost1, cost2; | ||
| 5994 | int i; | ||
| 5995 | |||
| 5996 | /* | ||
| 5997 | * Measure the migration cost of 'size' bytes, over an | ||
| 5998 | * average of 10 runs: | ||
| 5999 | * | ||
| 6000 | * (We perturb the cache size by a small (0..4k) | ||
| 6001 | * value to compensate size/alignment related artifacts. | ||
| 6002 | * We also subtract the cost of the operation done on | ||
| 6003 | * the same CPU.) | ||
| 6004 | */ | ||
| 6005 | cost1 = 0; | ||
| 6006 | |||
| 6007 | /* | ||
| 6008 | * dry run, to make sure we start off cache-cold on cpu1, | ||
| 6009 | * and to get any vmalloc pagefaults in advance: | ||
| 6010 | */ | ||
| 6011 | measure_one(cache, size, cpu1, cpu2); | ||
| 6012 | for (i = 0; i < ITERATIONS; i++) | ||
| 6013 | cost1 += measure_one(cache, size - i * 1024, cpu1, cpu2); | ||
| 6014 | |||
| 6015 | measure_one(cache, size, cpu2, cpu1); | ||
| 6016 | for (i = 0; i < ITERATIONS; i++) | ||
| 6017 | cost1 += measure_one(cache, size - i * 1024, cpu2, cpu1); | ||
| 6018 | |||
| 6019 | /* | ||
| 6020 | * (We measure the non-migrating [cached] cost on both | ||
| 6021 | * cpu1 and cpu2, to handle CPUs with different speeds) | ||
| 6022 | */ | ||
| 6023 | cost2 = 0; | ||
| 6024 | |||
| 6025 | measure_one(cache, size, cpu1, cpu1); | ||
| 6026 | for (i = 0; i < ITERATIONS; i++) | ||
| 6027 | cost2 += measure_one(cache, size - i * 1024, cpu1, cpu1); | ||
| 6028 | |||
| 6029 | measure_one(cache, size, cpu2, cpu2); | ||
| 6030 | for (i = 0; i < ITERATIONS; i++) | ||
| 6031 | cost2 += measure_one(cache, size - i * 1024, cpu2, cpu2); | ||
| 6032 | |||
| 6033 | /* | ||
| 6034 | * Get the per-iteration migration cost: | ||
| 6035 | */ | ||
| 6036 | do_div(cost1, 2 * ITERATIONS); | ||
| 6037 | do_div(cost2, 2 * ITERATIONS); | ||
| 6038 | |||
| 6039 | return cost1 - cost2; | ||
| 6040 | } | ||
| 6041 | |||
| 6042 | static unsigned long long measure_migration_cost(int cpu1, int cpu2) | ||
| 6043 | { | ||
| 6044 | unsigned long long max_cost = 0, fluct = 0, avg_fluct = 0; | ||
| 6045 | unsigned int max_size, size, size_found = 0; | ||
| 6046 | long long cost = 0, prev_cost; | ||
| 6047 | void *cache; | ||
| 6048 | |||
| 6049 | /* | ||
| 6050 | * Search from max_cache_size*5 down to 64K - the real relevant | ||
| 6051 | * cachesize has to lie somewhere inbetween. | ||
| 6052 | */ | ||
| 6053 | if (max_cache_size) { | ||
| 6054 | max_size = max(max_cache_size * SEARCH_SCOPE, MIN_CACHE_SIZE); | ||
| 6055 | size = max(max_cache_size / SEARCH_SCOPE, MIN_CACHE_SIZE); | ||
| 6056 | } else { | ||
| 6057 | /* | ||
| 6058 | * Since we have no estimation about the relevant | ||
| 6059 | * search range | ||
| 6060 | */ | ||
| 6061 | max_size = DEFAULT_CACHE_SIZE * SEARCH_SCOPE; | ||
| 6062 | size = MIN_CACHE_SIZE; | ||
| 6063 | } | ||
| 6064 | |||
| 6065 | if (!cpu_online(cpu1) || !cpu_online(cpu2)) { | ||
| 6066 | printk("cpu %d and %d not both online!\n", cpu1, cpu2); | ||
| 6067 | return 0; | ||
| 6068 | } | ||
| 6069 | |||
| 6070 | /* | ||
| 6071 | * Allocate the working set: | ||
| 6072 | */ | ||
| 6073 | cache = vmalloc(max_size); | ||
| 6074 | if (!cache) { | ||
| 6075 | printk("could not vmalloc %d bytes for cache!\n", 2 * max_size); | ||
| 6076 | return 1000000; /* return 1 msec on very small boxen */ | ||
| 6077 | } | ||
| 6078 | |||
| 6079 | while (size <= max_size) { | ||
| 6080 | prev_cost = cost; | ||
| 6081 | cost = measure_cost(cpu1, cpu2, cache, size); | ||
| 6082 | |||
| 6083 | /* | ||
| 6084 | * Update the max: | ||
| 6085 | */ | ||
| 6086 | if (cost > 0) { | ||
| 6087 | if (max_cost < cost) { | ||
| 6088 | max_cost = cost; | ||
| 6089 | size_found = size; | ||
| 6090 | } | ||
| 6091 | } | ||
| 6092 | /* | ||
| 6093 | * Calculate average fluctuation, we use this to prevent | ||
| 6094 | * noise from triggering an early break out of the loop: | ||
| 6095 | */ | ||
| 6096 | fluct = abs(cost - prev_cost); | ||
| 6097 | avg_fluct = (avg_fluct + fluct)/2; | ||
| 6098 | |||
| 6099 | if (migration_debug) | ||
| 6100 | printk("-> [%d][%d][%7d] %3ld.%ld [%3ld.%ld] (%ld): " | ||
| 6101 | "(%8Ld %8Ld)\n", | ||
| 6102 | cpu1, cpu2, size, | ||
| 6103 | (long)cost / 1000000, | ||
| 6104 | ((long)cost / 100000) % 10, | ||
| 6105 | (long)max_cost / 1000000, | ||
| 6106 | ((long)max_cost / 100000) % 10, | ||
| 6107 | domain_distance(cpu1, cpu2), | ||
| 6108 | cost, avg_fluct); | ||
| 6109 | |||
| 6110 | /* | ||
| 6111 | * If we iterated at least 20% past the previous maximum, | ||
| 6112 | * and the cost has dropped by more than 20% already, | ||
| 6113 | * (taking fluctuations into account) then we assume to | ||
| 6114 | * have found the maximum and break out of the loop early: | ||
| 6115 | */ | ||
| 6116 | if (size_found && (size*100 > size_found*SIZE_THRESH)) | ||
| 6117 | if (cost+avg_fluct <= 0 || | ||
| 6118 | max_cost*100 > (cost+avg_fluct)*COST_THRESH) { | ||
| 6119 | |||
| 6120 | if (migration_debug) | ||
| 6121 | printk("-> found max.\n"); | ||
| 6122 | break; | ||
| 6123 | } | ||
| 6124 | /* | ||
| 6125 | * Increase the cachesize in 10% steps: | ||
| 6126 | */ | ||
| 6127 | size = size * 10 / 9; | ||
| 6128 | } | ||
| 6129 | |||
| 6130 | if (migration_debug) | ||
| 6131 | printk("[%d][%d] working set size found: %d, cost: %Ld\n", | ||
| 6132 | cpu1, cpu2, size_found, max_cost); | ||
| 6133 | |||
| 6134 | vfree(cache); | ||
| 6135 | |||
| 6136 | /* | ||
| 6137 | * A task is considered 'cache cold' if at least 2 times | ||
| 6138 | * the worst-case cost of migration has passed. | ||
| 6139 | * | ||
| 6140 | * (this limit is only listened to if the load-balancing | ||
| 6141 | * situation is 'nice' - if there is a large imbalance we | ||
| 6142 | * ignore it for the sake of CPU utilization and | ||
| 6143 | * processing fairness.) | ||
| 6144 | */ | ||
| 6145 | return 2 * max_cost * migration_factor / MIGRATION_FACTOR_SCALE; | ||
| 6146 | } | ||
| 6147 | |||
| 6148 | static void calibrate_migration_costs(const cpumask_t *cpu_map) | ||
| 6149 | { | ||
| 6150 | int cpu1 = -1, cpu2 = -1, cpu, orig_cpu = raw_smp_processor_id(); | ||
| 6151 | unsigned long j0, j1, distance, max_distance = 0; | ||
| 6152 | struct sched_domain *sd; | ||
| 6153 | |||
| 6154 | j0 = jiffies; | ||
| 6155 | |||
| 6156 | /* | ||
| 6157 | * First pass - calculate the cacheflush times: | ||
| 6158 | */ | ||
| 6159 | for_each_cpu_mask(cpu1, *cpu_map) { | ||
| 6160 | for_each_cpu_mask(cpu2, *cpu_map) { | ||
| 6161 | if (cpu1 == cpu2) | ||
| 6162 | continue; | ||
| 6163 | distance = domain_distance(cpu1, cpu2); | ||
| 6164 | max_distance = max(max_distance, distance); | ||
| 6165 | /* | ||
| 6166 | * No result cached yet? | ||
| 6167 | */ | ||
| 6168 | if (migration_cost[distance] == -1LL) | ||
| 6169 | migration_cost[distance] = | ||
| 6170 | measure_migration_cost(cpu1, cpu2); | ||
| 6171 | } | ||
| 6172 | } | ||
| 6173 | /* | ||
| 6174 | * Second pass - update the sched domain hierarchy with | ||
| 6175 | * the new cache-hot-time estimations: | ||
| 6176 | */ | ||
| 6177 | for_each_cpu_mask(cpu, *cpu_map) { | ||
| 6178 | distance = 0; | ||
| 6179 | for_each_domain(cpu, sd) { | ||
| 6180 | sd->cache_hot_time = migration_cost[distance]; | ||
| 6181 | distance++; | ||
| 6182 | } | ||
| 6183 | } | ||
| 6184 | /* | ||
| 6185 | * Print the matrix: | ||
| 6186 | */ | ||
| 6187 | if (migration_debug) | ||
| 6188 | printk("migration: max_cache_size: %d, cpu: %d MHz:\n", | ||
| 6189 | max_cache_size, | ||
| 6190 | #ifdef CONFIG_X86 | ||
| 6191 | cpu_khz/1000 | ||
| 6192 | #else | ||
| 6193 | -1 | ||
| 6194 | #endif | ||
| 6195 | ); | ||
| 6196 | if (system_state == SYSTEM_BOOTING && num_online_cpus() > 1) { | ||
| 6197 | printk("migration_cost="); | ||
| 6198 | for (distance = 0; distance <= max_distance; distance++) { | ||
| 6199 | if (distance) | ||
| 6200 | printk(","); | ||
| 6201 | printk("%ld", (long)migration_cost[distance] / 1000); | ||
| 6202 | } | ||
| 6203 | printk("\n"); | ||
| 6204 | } | ||
| 6205 | j1 = jiffies; | ||
| 6206 | if (migration_debug) | ||
| 6207 | printk("migration: %ld seconds\n", (j1-j0) / HZ); | ||
| 6208 | |||
| 6209 | /* | ||
| 6210 | * Move back to the original CPU. NUMA-Q gets confused | ||
| 6211 | * if we migrate to another quad during bootup. | ||
| 6212 | */ | ||
| 6213 | if (raw_smp_processor_id() != orig_cpu) { | ||
| 6214 | cpumask_t mask = cpumask_of_cpu(orig_cpu), | ||
| 6215 | saved_mask = current->cpus_allowed; | ||
| 6216 | |||
| 6217 | set_cpus_allowed(current, mask); | ||
| 6218 | set_cpus_allowed(current, saved_mask); | ||
| 6219 | } | ||
| 6220 | } | ||
| 6221 | |||
| 6222 | #ifdef CONFIG_NUMA | 5488 | #ifdef CONFIG_NUMA |
| 6223 | 5489 | ||
| 6224 | /** | 5490 | /** |
| @@ -6519,7 +5785,6 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) | |||
| 6519 | static int build_sched_domains(const cpumask_t *cpu_map) | 5785 | static int build_sched_domains(const cpumask_t *cpu_map) |
| 6520 | { | 5786 | { |
| 6521 | int i; | 5787 | int i; |
| 6522 | struct sched_domain *sd; | ||
| 6523 | #ifdef CONFIG_NUMA | 5788 | #ifdef CONFIG_NUMA |
| 6524 | struct sched_group **sched_group_nodes = NULL; | 5789 | struct sched_group **sched_group_nodes = NULL; |
| 6525 | int sd_allnodes = 0; | 5790 | int sd_allnodes = 0; |
| @@ -6527,7 +5792,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6527 | /* | 5792 | /* |
| 6528 | * Allocate the per-node list of sched groups | 5793 | * Allocate the per-node list of sched groups |
| 6529 | */ | 5794 | */ |
| 6530 | sched_group_nodes = kzalloc(sizeof(struct sched_group*)*MAX_NUMNODES, | 5795 | sched_group_nodes = kzalloc(sizeof(struct sched_group *)*MAX_NUMNODES, |
| 6531 | GFP_KERNEL); | 5796 | GFP_KERNEL); |
| 6532 | if (!sched_group_nodes) { | 5797 | if (!sched_group_nodes) { |
| 6533 | printk(KERN_WARNING "Can not alloc sched group node list\n"); | 5798 | printk(KERN_WARNING "Can not alloc sched group node list\n"); |
| @@ -6546,8 +5811,8 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6546 | cpus_and(nodemask, nodemask, *cpu_map); | 5811 | cpus_and(nodemask, nodemask, *cpu_map); |
| 6547 | 5812 | ||
| 6548 | #ifdef CONFIG_NUMA | 5813 | #ifdef CONFIG_NUMA |
| 6549 | if (cpus_weight(*cpu_map) | 5814 | if (cpus_weight(*cpu_map) > |
| 6550 | > SD_NODES_PER_DOMAIN*cpus_weight(nodemask)) { | 5815 | SD_NODES_PER_DOMAIN*cpus_weight(nodemask)) { |
| 6551 | sd = &per_cpu(allnodes_domains, i); | 5816 | sd = &per_cpu(allnodes_domains, i); |
| 6552 | *sd = SD_ALLNODES_INIT; | 5817 | *sd = SD_ALLNODES_INIT; |
| 6553 | sd->span = *cpu_map; | 5818 | sd->span = *cpu_map; |
| @@ -6606,7 +5871,8 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6606 | if (i != first_cpu(this_sibling_map)) | 5871 | if (i != first_cpu(this_sibling_map)) |
| 6607 | continue; | 5872 | continue; |
| 6608 | 5873 | ||
| 6609 | init_sched_build_groups(this_sibling_map, cpu_map, &cpu_to_cpu_group); | 5874 | init_sched_build_groups(this_sibling_map, cpu_map, |
| 5875 | &cpu_to_cpu_group); | ||
| 6610 | } | 5876 | } |
| 6611 | #endif | 5877 | #endif |
| 6612 | 5878 | ||
| @@ -6617,11 +5883,11 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6617 | cpus_and(this_core_map, this_core_map, *cpu_map); | 5883 | cpus_and(this_core_map, this_core_map, *cpu_map); |
| 6618 | if (i != first_cpu(this_core_map)) | 5884 | if (i != first_cpu(this_core_map)) |
| 6619 | continue; | 5885 | continue; |
| 6620 | init_sched_build_groups(this_core_map, cpu_map, &cpu_to_core_group); | 5886 | init_sched_build_groups(this_core_map, cpu_map, |
| 5887 | &cpu_to_core_group); | ||
| 6621 | } | 5888 | } |
| 6622 | #endif | 5889 | #endif |
| 6623 | 5890 | ||
| 6624 | |||
| 6625 | /* Set up physical groups */ | 5891 | /* Set up physical groups */ |
| 6626 | for (i = 0; i < MAX_NUMNODES; i++) { | 5892 | for (i = 0; i < MAX_NUMNODES; i++) { |
| 6627 | cpumask_t nodemask = node_to_cpumask(i); | 5893 | cpumask_t nodemask = node_to_cpumask(i); |
| @@ -6636,7 +5902,8 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6636 | #ifdef CONFIG_NUMA | 5902 | #ifdef CONFIG_NUMA |
| 6637 | /* Set up node groups */ | 5903 | /* Set up node groups */ |
| 6638 | if (sd_allnodes) | 5904 | if (sd_allnodes) |
| 6639 | init_sched_build_groups(*cpu_map, cpu_map, &cpu_to_allnodes_group); | 5905 | init_sched_build_groups(*cpu_map, cpu_map, |
| 5906 | &cpu_to_allnodes_group); | ||
| 6640 | 5907 | ||
| 6641 | for (i = 0; i < MAX_NUMNODES; i++) { | 5908 | for (i = 0; i < MAX_NUMNODES; i++) { |
| 6642 | /* Set up node groups */ | 5909 | /* Set up node groups */ |
| @@ -6664,6 +5931,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6664 | sched_group_nodes[i] = sg; | 5931 | sched_group_nodes[i] = sg; |
| 6665 | for_each_cpu_mask(j, nodemask) { | 5932 | for_each_cpu_mask(j, nodemask) { |
| 6666 | struct sched_domain *sd; | 5933 | struct sched_domain *sd; |
| 5934 | |||
| 6667 | sd = &per_cpu(node_domains, j); | 5935 | sd = &per_cpu(node_domains, j); |
| 6668 | sd->groups = sg; | 5936 | sd->groups = sg; |
| 6669 | } | 5937 | } |
| @@ -6708,19 +5976,22 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6708 | /* Calculate CPU power for physical packages and nodes */ | 5976 | /* Calculate CPU power for physical packages and nodes */ |
| 6709 | #ifdef CONFIG_SCHED_SMT | 5977 | #ifdef CONFIG_SCHED_SMT |
| 6710 | for_each_cpu_mask(i, *cpu_map) { | 5978 | for_each_cpu_mask(i, *cpu_map) { |
| 6711 | sd = &per_cpu(cpu_domains, i); | 5979 | struct sched_domain *sd = &per_cpu(cpu_domains, i); |
| 5980 | |||
| 6712 | init_sched_groups_power(i, sd); | 5981 | init_sched_groups_power(i, sd); |
| 6713 | } | 5982 | } |
| 6714 | #endif | 5983 | #endif |
| 6715 | #ifdef CONFIG_SCHED_MC | 5984 | #ifdef CONFIG_SCHED_MC |
| 6716 | for_each_cpu_mask(i, *cpu_map) { | 5985 | for_each_cpu_mask(i, *cpu_map) { |
| 6717 | sd = &per_cpu(core_domains, i); | 5986 | struct sched_domain *sd = &per_cpu(core_domains, i); |
| 5987 | |||
| 6718 | init_sched_groups_power(i, sd); | 5988 | init_sched_groups_power(i, sd); |
| 6719 | } | 5989 | } |
| 6720 | #endif | 5990 | #endif |
| 6721 | 5991 | ||
| 6722 | for_each_cpu_mask(i, *cpu_map) { | 5992 | for_each_cpu_mask(i, *cpu_map) { |
| 6723 | sd = &per_cpu(phys_domains, i); | 5993 | struct sched_domain *sd = &per_cpu(phys_domains, i); |
| 5994 | |||
| 6724 | init_sched_groups_power(i, sd); | 5995 | init_sched_groups_power(i, sd); |
| 6725 | } | 5996 | } |
| 6726 | 5997 | ||
| @@ -6748,10 +6019,6 @@ static int build_sched_domains(const cpumask_t *cpu_map) | |||
| 6748 | #endif | 6019 | #endif |
| 6749 | cpu_attach_domain(sd, i); | 6020 | cpu_attach_domain(sd, i); |
| 6750 | } | 6021 | } |
| 6751 | /* | ||
| 6752 | * Tune cache-hot values: | ||
| 6753 | */ | ||
| 6754 | calibrate_migration_costs(cpu_map); | ||
| 6755 | 6022 | ||
| 6756 | return 0; | 6023 | return 0; |
| 6757 | 6024 | ||
| @@ -6958,10 +6225,12 @@ void __init sched_init_smp(void) | |||
| 6958 | /* Move init over to a non-isolated CPU */ | 6225 | /* Move init over to a non-isolated CPU */ |
| 6959 | if (set_cpus_allowed(current, non_isolated_cpus) < 0) | 6226 | if (set_cpus_allowed(current, non_isolated_cpus) < 0) |
| 6960 | BUG(); | 6227 | BUG(); |
| 6228 | sched_init_granularity(); | ||
| 6961 | } | 6229 | } |
| 6962 | #else | 6230 | #else |
| 6963 | void __init sched_init_smp(void) | 6231 | void __init sched_init_smp(void) |
| 6964 | { | 6232 | { |
| 6233 | sched_init_granularity(); | ||
| 6965 | } | 6234 | } |
| 6966 | #endif /* CONFIG_SMP */ | 6235 | #endif /* CONFIG_SMP */ |
| 6967 | 6236 | ||
| @@ -6975,28 +6244,51 @@ int in_sched_functions(unsigned long addr) | |||
| 6975 | && addr < (unsigned long)__sched_text_end); | 6244 | && addr < (unsigned long)__sched_text_end); |
| 6976 | } | 6245 | } |
| 6977 | 6246 | ||
| 6247 | static inline void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq) | ||
| 6248 | { | ||
| 6249 | cfs_rq->tasks_timeline = RB_ROOT; | ||
| 6250 | cfs_rq->fair_clock = 1; | ||
| 6251 | #ifdef CONFIG_FAIR_GROUP_SCHED | ||
| 6252 | cfs_rq->rq = rq; | ||
| 6253 | #endif | ||
| 6254 | } | ||
| 6255 | |||
| 6978 | void __init sched_init(void) | 6256 | void __init sched_init(void) |
| 6979 | { | 6257 | { |
| 6980 | int i, j, k; | 6258 | u64 now = sched_clock(); |
| 6981 | int highest_cpu = 0; | 6259 | int highest_cpu = 0; |
| 6260 | int i, j; | ||
| 6261 | |||
| 6262 | /* | ||
| 6263 | * Link up the scheduling class hierarchy: | ||
| 6264 | */ | ||
| 6265 | rt_sched_class.next = &fair_sched_class; | ||
| 6266 | fair_sched_class.next = &idle_sched_class; | ||
| 6267 | idle_sched_class.next = NULL; | ||
| 6982 | 6268 | ||
| 6983 | for_each_possible_cpu(i) { | 6269 | for_each_possible_cpu(i) { |
| 6984 | struct prio_array *array; | 6270 | struct rt_prio_array *array; |
| 6985 | struct rq *rq; | 6271 | struct rq *rq; |
| 6986 | 6272 | ||
| 6987 | rq = cpu_rq(i); | 6273 | rq = cpu_rq(i); |
| 6988 | spin_lock_init(&rq->lock); | 6274 | spin_lock_init(&rq->lock); |
| 6989 | lockdep_set_class(&rq->lock, &rq->rq_lock_key); | 6275 | lockdep_set_class(&rq->lock, &rq->rq_lock_key); |
| 6990 | rq->nr_running = 0; | 6276 | rq->nr_running = 0; |
| 6991 | rq->active = rq->arrays; | 6277 | rq->clock = 1; |
| 6992 | rq->expired = rq->arrays + 1; | 6278 | init_cfs_rq(&rq->cfs, rq); |
| 6993 | rq->best_expired_prio = MAX_PRIO; | 6279 | #ifdef CONFIG_FAIR_GROUP_SCHED |
| 6280 | INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); | ||
| 6281 | list_add(&rq->cfs.leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); | ||
| 6282 | #endif | ||
| 6283 | rq->ls.load_update_last = now; | ||
| 6284 | rq->ls.load_update_start = now; | ||
| 6994 | 6285 | ||
| 6286 | for (j = 0; j < CPU_LOAD_IDX_MAX; j++) | ||
| 6287 | rq->cpu_load[j] = 0; | ||
| 6995 | #ifdef CONFIG_SMP | 6288 | #ifdef CONFIG_SMP |
| 6996 | rq->sd = NULL; | 6289 | rq->sd = NULL; |
| 6997 | for (j = 1; j < 3; j++) | ||
| 6998 | rq->cpu_load[j] = 0; | ||
| 6999 | rq->active_balance = 0; | 6290 | rq->active_balance = 0; |
| 6291 | rq->next_balance = jiffies; | ||
| 7000 | rq->push_cpu = 0; | 6292 | rq->push_cpu = 0; |
| 7001 | rq->cpu = i; | 6293 | rq->cpu = i; |
| 7002 | rq->migration_thread = NULL; | 6294 | rq->migration_thread = NULL; |
| @@ -7004,16 +6296,14 @@ void __init sched_init(void) | |||
| 7004 | #endif | 6296 | #endif |
| 7005 | atomic_set(&rq->nr_iowait, 0); | 6297 | atomic_set(&rq->nr_iowait, 0); |
| 7006 | 6298 | ||
| 7007 | for (j = 0; j < 2; j++) { | 6299 | array = &rq->rt.active; |
| 7008 | array = rq->arrays + j; | 6300 | for (j = 0; j < MAX_RT_PRIO; j++) { |
| 7009 | for (k = 0; k < MAX_PRIO; k++) { | 6301 | INIT_LIST_HEAD(array->queue + j); |
| 7010 | INIT_LIST_HEAD(array->queue + k); | 6302 | __clear_bit(j, array->bitmap); |
| 7011 | __clear_bit(k, array->bitmap); | ||
| 7012 | } | ||
| 7013 | // delimiter for bitsearch | ||
| 7014 | __set_bit(MAX_PRIO, array->bitmap); | ||
| 7015 | } | 6303 | } |
| 7016 | highest_cpu = i; | 6304 | highest_cpu = i; |
| 6305 | /* delimiter for bitsearch: */ | ||
| 6306 | __set_bit(MAX_RT_PRIO, array->bitmap); | ||
| 7017 | } | 6307 | } |
| 7018 | 6308 | ||
| 7019 | set_load_weight(&init_task); | 6309 | set_load_weight(&init_task); |
| @@ -7040,6 +6330,10 @@ void __init sched_init(void) | |||
| 7040 | * when this runqueue becomes "idle". | 6330 | * when this runqueue becomes "idle". |
| 7041 | */ | 6331 | */ |
| 7042 | init_idle(current, smp_processor_id()); | 6332 | init_idle(current, smp_processor_id()); |
| 6333 | /* | ||
| 6334 | * During early bootup we pretend to be a normal task: | ||
| 6335 | */ | ||
| 6336 | current->sched_class = &fair_sched_class; | ||
| 7043 | } | 6337 | } |
| 7044 | 6338 | ||
| 7045 | #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP | 6339 | #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP |
| @@ -7070,31 +6364,59 @@ EXPORT_SYMBOL(__might_sleep); | |||
| 7070 | #ifdef CONFIG_MAGIC_SYSRQ | 6364 | #ifdef CONFIG_MAGIC_SYSRQ |
| 7071 | void normalize_rt_tasks(void) | 6365 | void normalize_rt_tasks(void) |
| 7072 | { | 6366 | { |
| 7073 | struct prio_array *array; | 6367 | struct task_struct *g, *p; |
| 7074 | struct task_struct *p; | ||
| 7075 | unsigned long flags; | 6368 | unsigned long flags; |
| 7076 | struct rq *rq; | 6369 | struct rq *rq; |
| 6370 | int on_rq; | ||
| 7077 | 6371 | ||
| 7078 | read_lock_irq(&tasklist_lock); | 6372 | read_lock_irq(&tasklist_lock); |
| 7079 | for_each_process(p) { | 6373 | do_each_thread(g, p) { |
| 7080 | if (!rt_task(p)) | 6374 | p->se.fair_key = 0; |
| 6375 | p->se.wait_runtime = 0; | ||
| 6376 | p->se.wait_start_fair = 0; | ||
| 6377 | p->se.wait_start = 0; | ||
| 6378 | p->se.exec_start = 0; | ||
| 6379 | p->se.sleep_start = 0; | ||
| 6380 | p->se.sleep_start_fair = 0; | ||
| 6381 | p->se.block_start = 0; | ||
| 6382 | task_rq(p)->cfs.fair_clock = 0; | ||
| 6383 | task_rq(p)->clock = 0; | ||
| 6384 | |||
| 6385 | if (!rt_task(p)) { | ||
| 6386 | /* | ||
| 6387 | * Renice negative nice level userspace | ||
| 6388 | * tasks back to 0: | ||
| 6389 | */ | ||
| 6390 | if (TASK_NICE(p) < 0 && p->mm) | ||
| 6391 | set_user_nice(p, 0); | ||
| 7081 | continue; | 6392 | continue; |
| 6393 | } | ||
| 7082 | 6394 | ||
| 7083 | spin_lock_irqsave(&p->pi_lock, flags); | 6395 | spin_lock_irqsave(&p->pi_lock, flags); |
| 7084 | rq = __task_rq_lock(p); | 6396 | rq = __task_rq_lock(p); |
| 6397 | #ifdef CONFIG_SMP | ||
| 6398 | /* | ||
| 6399 | * Do not touch the migration thread: | ||
| 6400 | */ | ||
| 6401 | if (p == rq->migration_thread) | ||
| 6402 | goto out_unlock; | ||
| 6403 | #endif | ||
| 7085 | 6404 | ||
| 7086 | array = p->array; | 6405 | on_rq = p->se.on_rq; |
| 7087 | if (array) | 6406 | if (on_rq) |
| 7088 | deactivate_task(p, task_rq(p)); | 6407 | deactivate_task(task_rq(p), p, 0); |
| 7089 | __setscheduler(p, SCHED_NORMAL, 0); | 6408 | __setscheduler(rq, p, SCHED_NORMAL, 0); |
| 7090 | if (array) { | 6409 | if (on_rq) { |
| 7091 | __activate_task(p, task_rq(p)); | 6410 | activate_task(task_rq(p), p, 0); |
| 7092 | resched_task(rq->curr); | 6411 | resched_task(rq->curr); |
| 7093 | } | 6412 | } |
| 7094 | 6413 | #ifdef CONFIG_SMP | |
| 6414 | out_unlock: | ||
| 6415 | #endif | ||
| 7095 | __task_rq_unlock(rq); | 6416 | __task_rq_unlock(rq); |
| 7096 | spin_unlock_irqrestore(&p->pi_lock, flags); | 6417 | spin_unlock_irqrestore(&p->pi_lock, flags); |
| 7097 | } | 6418 | } while_each_thread(g, p); |
| 6419 | |||
| 7098 | read_unlock_irq(&tasklist_lock); | 6420 | read_unlock_irq(&tasklist_lock); |
| 7099 | } | 6421 | } |
| 7100 | 6422 | ||
