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-rw-r--r--kernel/rcutree.h104
1 files changed, 84 insertions, 20 deletions
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index e8f057e44e3e..257664815d5d 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -91,6 +91,14 @@ struct rcu_dynticks {
91 /* remains even for nmi from irq handler. */ 91 /* remains even for nmi from irq handler. */
92}; 92};
93 93
94/* RCU's kthread states for tracing. */
95#define RCU_KTHREAD_STOPPED 0
96#define RCU_KTHREAD_RUNNING 1
97#define RCU_KTHREAD_WAITING 2
98#define RCU_KTHREAD_OFFCPU 3
99#define RCU_KTHREAD_YIELDING 4
100#define RCU_KTHREAD_MAX 4
101
94/* 102/*
95 * Definition for node within the RCU grace-period-detection hierarchy. 103 * Definition for node within the RCU grace-period-detection hierarchy.
96 */ 104 */
@@ -109,10 +117,11 @@ struct rcu_node {
109 /* an rcu_data structure, otherwise, each */ 117 /* an rcu_data structure, otherwise, each */
110 /* bit corresponds to a child rcu_node */ 118 /* bit corresponds to a child rcu_node */
111 /* structure. */ 119 /* structure. */
112 unsigned long expmask; /* Groups that have ->blocked_tasks[] */ 120 unsigned long expmask; /* Groups that have ->blkd_tasks */
113 /* elements that need to drain to allow the */ 121 /* elements that need to drain to allow the */
114 /* current expedited grace period to */ 122 /* current expedited grace period to */
115 /* complete (only for TREE_PREEMPT_RCU). */ 123 /* complete (only for TREE_PREEMPT_RCU). */
124 unsigned long wakemask; /* CPUs whose kthread needs to be awakened. */
116 unsigned long qsmaskinit; 125 unsigned long qsmaskinit;
117 /* Per-GP initial value for qsmask & expmask. */ 126 /* Per-GP initial value for qsmask & expmask. */
118 unsigned long grpmask; /* Mask to apply to parent qsmask. */ 127 unsigned long grpmask; /* Mask to apply to parent qsmask. */
@@ -122,11 +131,68 @@ struct rcu_node {
122 u8 grpnum; /* CPU/group number for next level up. */ 131 u8 grpnum; /* CPU/group number for next level up. */
123 u8 level; /* root is at level 0. */ 132 u8 level; /* root is at level 0. */
124 struct rcu_node *parent; 133 struct rcu_node *parent;
125 struct list_head blocked_tasks[4]; 134 struct list_head blkd_tasks;
126 /* Tasks blocked in RCU read-side critsect. */ 135 /* Tasks blocked in RCU read-side critical */
127 /* Grace period number (->gpnum) x blocked */ 136 /* section. Tasks are placed at the head */
128 /* by tasks on the (x & 0x1) element of the */ 137 /* of this list and age towards the tail. */
129 /* blocked_tasks[] array. */ 138 struct list_head *gp_tasks;
139 /* Pointer to the first task blocking the */
140 /* current grace period, or NULL if there */
141 /* is no such task. */
142 struct list_head *exp_tasks;
143 /* Pointer to the first task blocking the */
144 /* current expedited grace period, or NULL */
145 /* if there is no such task. If there */
146 /* is no current expedited grace period, */
147 /* then there can cannot be any such task. */
148#ifdef CONFIG_RCU_BOOST
149 struct list_head *boost_tasks;
150 /* Pointer to first task that needs to be */
151 /* priority boosted, or NULL if no priority */
152 /* boosting is needed for this rcu_node */
153 /* structure. If there are no tasks */
154 /* queued on this rcu_node structure that */
155 /* are blocking the current grace period, */
156 /* there can be no such task. */
157 unsigned long boost_time;
158 /* When to start boosting (jiffies). */
159 struct task_struct *boost_kthread_task;
160 /* kthread that takes care of priority */
161 /* boosting for this rcu_node structure. */
162 wait_queue_head_t boost_wq;
163 /* Wait queue on which to park the boost */
164 /* kthread. */
165 unsigned int boost_kthread_status;
166 /* State of boost_kthread_task for tracing. */
167 unsigned long n_tasks_boosted;
168 /* Total number of tasks boosted. */
169 unsigned long n_exp_boosts;
170 /* Number of tasks boosted for expedited GP. */
171 unsigned long n_normal_boosts;
172 /* Number of tasks boosted for normal GP. */
173 unsigned long n_balk_blkd_tasks;
174 /* Refused to boost: no blocked tasks. */
175 unsigned long n_balk_exp_gp_tasks;
176 /* Refused to boost: nothing blocking GP. */
177 unsigned long n_balk_boost_tasks;
178 /* Refused to boost: already boosting. */
179 unsigned long n_balk_notblocked;
180 /* Refused to boost: RCU RS CS still running. */
181 unsigned long n_balk_notyet;
182 /* Refused to boost: not yet time. */
183 unsigned long n_balk_nos;
184 /* Refused to boost: not sure why, though. */
185 /* This can happen due to race conditions. */
186#endif /* #ifdef CONFIG_RCU_BOOST */
187 struct task_struct *node_kthread_task;
188 /* kthread that takes care of this rcu_node */
189 /* structure, for example, awakening the */
190 /* per-CPU kthreads as needed. */
191 wait_queue_head_t node_wq;
192 /* Wait queue on which to park the per-node */
193 /* kthread. */
194 unsigned int node_kthread_status;
195 /* State of node_kthread_task for tracing. */
130} ____cacheline_internodealigned_in_smp; 196} ____cacheline_internodealigned_in_smp;
131 197
132/* 198/*
@@ -175,7 +241,7 @@ struct rcu_data {
175 bool passed_quiesc; /* User-mode/idle loop etc. */ 241 bool passed_quiesc; /* User-mode/idle loop etc. */
176 bool qs_pending; /* Core waits for quiesc state. */ 242 bool qs_pending; /* Core waits for quiesc state. */
177 bool beenonline; /* CPU online at least once. */ 243 bool beenonline; /* CPU online at least once. */
178 bool preemptable; /* Preemptable RCU? */ 244 bool preemptible; /* Preemptible RCU? */
179 struct rcu_node *mynode; /* This CPU's leaf of hierarchy */ 245 struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
180 unsigned long grpmask; /* Mask to apply to leaf qsmask. */ 246 unsigned long grpmask; /* Mask to apply to leaf qsmask. */
181 247
@@ -254,7 +320,6 @@ struct rcu_data {
254#endif /* #else #ifdef CONFIG_NO_HZ */ 320#endif /* #else #ifdef CONFIG_NO_HZ */
255 321
256#define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */ 322#define RCU_JIFFIES_TILL_FORCE_QS 3 /* for rsp->jiffies_force_qs */
257#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
258 323
259#ifdef CONFIG_PROVE_RCU 324#ifdef CONFIG_PROVE_RCU
260#define RCU_STALL_DELAY_DELTA (5 * HZ) 325#define RCU_STALL_DELAY_DELTA (5 * HZ)
@@ -272,13 +337,6 @@ struct rcu_data {
272 /* scheduling clock irq */ 337 /* scheduling clock irq */
273 /* before ratting on them. */ 338 /* before ratting on them. */
274 339
275#ifdef CONFIG_RCU_CPU_STALL_DETECTOR_RUNNABLE
276#define RCU_CPU_STALL_SUPPRESS_INIT 0
277#else
278#define RCU_CPU_STALL_SUPPRESS_INIT 1
279#endif
280
281#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
282 340
283/* 341/*
284 * RCU global state, including node hierarchy. This hierarchy is 342 * RCU global state, including node hierarchy. This hierarchy is
@@ -325,12 +383,12 @@ struct rcu_state {
325 /* due to lock unavailable. */ 383 /* due to lock unavailable. */
326 unsigned long n_force_qs_ngp; /* Number of calls leaving */ 384 unsigned long n_force_qs_ngp; /* Number of calls leaving */
327 /* due to no GP active. */ 385 /* due to no GP active. */
328#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
329 unsigned long gp_start; /* Time at which GP started, */ 386 unsigned long gp_start; /* Time at which GP started, */
330 /* but in jiffies. */ 387 /* but in jiffies. */
331 unsigned long jiffies_stall; /* Time at which to check */ 388 unsigned long jiffies_stall; /* Time at which to check */
332 /* for CPU stalls. */ 389 /* for CPU stalls. */
333#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */ 390 unsigned long gp_max; /* Maximum GP duration in */
391 /* jiffies. */
334 char *name; /* Name of structure. */ 392 char *name; /* Name of structure. */
335}; 393};
336 394
@@ -361,16 +419,14 @@ DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
361static void rcu_bootup_announce(void); 419static void rcu_bootup_announce(void);
362long rcu_batches_completed(void); 420long rcu_batches_completed(void);
363static void rcu_preempt_note_context_switch(int cpu); 421static void rcu_preempt_note_context_switch(int cpu);
364static int rcu_preempted_readers(struct rcu_node *rnp); 422static int rcu_preempt_blocked_readers_cgp(struct rcu_node *rnp);
365#ifdef CONFIG_HOTPLUG_CPU 423#ifdef CONFIG_HOTPLUG_CPU
366static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp, 424static void rcu_report_unblock_qs_rnp(struct rcu_node *rnp,
367 unsigned long flags); 425 unsigned long flags);
368#endif /* #ifdef CONFIG_HOTPLUG_CPU */ 426#endif /* #ifdef CONFIG_HOTPLUG_CPU */
369#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
370static void rcu_print_detail_task_stall(struct rcu_state *rsp); 427static void rcu_print_detail_task_stall(struct rcu_state *rsp);
371static void rcu_print_task_stall(struct rcu_node *rnp); 428static void rcu_print_task_stall(struct rcu_node *rnp);
372static void rcu_preempt_stall_reset(void); 429static void rcu_preempt_stall_reset(void);
373#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
374static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp); 430static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
375#ifdef CONFIG_HOTPLUG_CPU 431#ifdef CONFIG_HOTPLUG_CPU
376static int rcu_preempt_offline_tasks(struct rcu_state *rsp, 432static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
@@ -390,5 +446,13 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
390static void rcu_preempt_send_cbs_to_online(void); 446static void rcu_preempt_send_cbs_to_online(void);
391static void __init __rcu_init_preempt(void); 447static void __init __rcu_init_preempt(void);
392static void rcu_needs_cpu_flush(void); 448static void rcu_needs_cpu_flush(void);
449static void __init rcu_init_boost_waitqueue(struct rcu_node *rnp);
450static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags);
451static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp,
452 cpumask_var_t cm);
453static void rcu_preempt_boost_start_gp(struct rcu_node *rnp);
454static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
455 struct rcu_node *rnp,
456 int rnp_index);
393 457
394#endif /* #ifndef RCU_TREE_NONCORE */ 458#endif /* #ifndef RCU_TREE_NONCORE */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-22 23:47:32 -0500