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-rw-r--r--include/linux/async.h1
-rw-r--r--include/linux/workqueue.h35
-rw-r--r--include/trace/events/workqueue.h10
-rw-r--r--kernel/async.c14
-rw-r--r--kernel/sched/core.c2
-rw-r--r--kernel/workqueue.c1530
-rw-r--r--kernel/workqueue_internal.h65
-rw-r--r--kernel/workqueue_sched.h9
8 files changed, 818 insertions, 848 deletions
diff --git a/include/linux/async.h b/include/linux/async.h
index 7a24fe9b44b4..345169cfa304 100644
--- a/include/linux/async.h
+++ b/include/linux/async.h
@@ -52,4 +52,5 @@ extern void async_synchronize_full_domain(struct async_domain *domain);
52extern void async_synchronize_cookie(async_cookie_t cookie); 52extern void async_synchronize_cookie(async_cookie_t cookie);
53extern void async_synchronize_cookie_domain(async_cookie_t cookie, 53extern void async_synchronize_cookie_domain(async_cookie_t cookie,
54 struct async_domain *domain); 54 struct async_domain *domain);
55extern bool current_is_async(void);
55#endif 56#endif
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 2b58905d3504..8afab27cdbc2 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -27,7 +27,7 @@ void delayed_work_timer_fn(unsigned long __data);
27enum { 27enum {
28 WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */ 28 WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
29 WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */ 29 WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */
30 WORK_STRUCT_CWQ_BIT = 2, /* data points to cwq */ 30 WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */
31 WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */ 31 WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */
32#ifdef CONFIG_DEBUG_OBJECTS_WORK 32#ifdef CONFIG_DEBUG_OBJECTS_WORK
33 WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */ 33 WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */
@@ -40,7 +40,7 @@ enum {
40 40
41 WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT, 41 WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
42 WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT, 42 WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT,
43 WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_BIT, 43 WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT,
44 WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT, 44 WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
45#ifdef CONFIG_DEBUG_OBJECTS_WORK 45#ifdef CONFIG_DEBUG_OBJECTS_WORK
46 WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT, 46 WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
@@ -57,29 +57,36 @@ enum {
57 57
58 /* special cpu IDs */ 58 /* special cpu IDs */
59 WORK_CPU_UNBOUND = NR_CPUS, 59 WORK_CPU_UNBOUND = NR_CPUS,
60 WORK_CPU_NONE = NR_CPUS + 1, 60 WORK_CPU_END = NR_CPUS + 1,
61 WORK_CPU_LAST = WORK_CPU_NONE,
62 61
63 /* 62 /*
64 * Reserve 7 bits off of cwq pointer w/ debugobjects turned 63 * Reserve 7 bits off of pwq pointer w/ debugobjects turned off.
65 * off. This makes cwqs aligned to 256 bytes and allows 15 64 * This makes pwqs aligned to 256 bytes and allows 15 workqueue
66 * workqueue flush colors. 65 * flush colors.
67 */ 66 */
68 WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT + 67 WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
69 WORK_STRUCT_COLOR_BITS, 68 WORK_STRUCT_COLOR_BITS,
70 69
71 /* data contains off-queue information when !WORK_STRUCT_CWQ */ 70 /* data contains off-queue information when !WORK_STRUCT_PWQ */
72 WORK_OFFQ_FLAG_BASE = WORK_STRUCT_FLAG_BITS, 71 WORK_OFFQ_FLAG_BASE = WORK_STRUCT_FLAG_BITS,
73 72
74 WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE), 73 WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE),
75 74
75 /*
76 * When a work item is off queue, its high bits point to the last
77 * pool it was on. Cap at 31 bits and use the highest number to
78 * indicate that no pool is associated.
79 */
76 WORK_OFFQ_FLAG_BITS = 1, 80 WORK_OFFQ_FLAG_BITS = 1,
77 WORK_OFFQ_CPU_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS, 81 WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
82 WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
83 WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
84 WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1,
78 85
79 /* convenience constants */ 86 /* convenience constants */
80 WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1, 87 WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
81 WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK, 88 WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
82 WORK_STRUCT_NO_CPU = (unsigned long)WORK_CPU_NONE << WORK_OFFQ_CPU_SHIFT, 89 WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
83 90
84 /* bit mask for work_busy() return values */ 91 /* bit mask for work_busy() return values */
85 WORK_BUSY_PENDING = 1 << 0, 92 WORK_BUSY_PENDING = 1 << 0,
@@ -95,13 +102,16 @@ struct work_struct {
95#endif 102#endif
96}; 103};
97 104
98#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU) 105#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL)
99#define WORK_DATA_STATIC_INIT() \ 106#define WORK_DATA_STATIC_INIT() \
100 ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU | WORK_STRUCT_STATIC) 107 ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)
101 108
102struct delayed_work { 109struct delayed_work {
103 struct work_struct work; 110 struct work_struct work;
104 struct timer_list timer; 111 struct timer_list timer;
112
113 /* target workqueue and CPU ->timer uses to queue ->work */
114 struct workqueue_struct *wq;
105 int cpu; 115 int cpu;
106}; 116};
107 117
@@ -426,7 +436,6 @@ extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
426extern void workqueue_set_max_active(struct workqueue_struct *wq, 436extern void workqueue_set_max_active(struct workqueue_struct *wq,
427 int max_active); 437 int max_active);
428extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq); 438extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
429extern unsigned int work_cpu(struct work_struct *work);
430extern unsigned int work_busy(struct work_struct *work); 439extern unsigned int work_busy(struct work_struct *work);
431 440
432/* 441/*
diff --git a/include/trace/events/workqueue.h b/include/trace/events/workqueue.h
index f28d1b65f178..bf0e18ba6cfb 100644
--- a/include/trace/events/workqueue.h
+++ b/include/trace/events/workqueue.h
@@ -27,7 +27,7 @@ DECLARE_EVENT_CLASS(workqueue_work,
27/** 27/**
28 * workqueue_queue_work - called when a work gets queued 28 * workqueue_queue_work - called when a work gets queued
29 * @req_cpu: the requested cpu 29 * @req_cpu: the requested cpu
30 * @cwq: pointer to struct cpu_workqueue_struct 30 * @pwq: pointer to struct pool_workqueue
31 * @work: pointer to struct work_struct 31 * @work: pointer to struct work_struct
32 * 32 *
33 * This event occurs when a work is queued immediately or once a 33 * This event occurs when a work is queued immediately or once a
@@ -36,10 +36,10 @@ DECLARE_EVENT_CLASS(workqueue_work,
36 */ 36 */
37TRACE_EVENT(workqueue_queue_work, 37TRACE_EVENT(workqueue_queue_work,
38 38
39 TP_PROTO(unsigned int req_cpu, struct cpu_workqueue_struct *cwq, 39 TP_PROTO(unsigned int req_cpu, struct pool_workqueue *pwq,
40 struct work_struct *work), 40 struct work_struct *work),
41 41
42 TP_ARGS(req_cpu, cwq, work), 42 TP_ARGS(req_cpu, pwq, work),
43 43
44 TP_STRUCT__entry( 44 TP_STRUCT__entry(
45 __field( void *, work ) 45 __field( void *, work )
@@ -52,9 +52,9 @@ TRACE_EVENT(workqueue_queue_work,
52 TP_fast_assign( 52 TP_fast_assign(
53 __entry->work = work; 53 __entry->work = work;
54 __entry->function = work->func; 54 __entry->function = work->func;
55 __entry->workqueue = cwq->wq; 55 __entry->workqueue = pwq->wq;
56 __entry->req_cpu = req_cpu; 56 __entry->req_cpu = req_cpu;
57 __entry->cpu = cwq->pool->gcwq->cpu; 57 __entry->cpu = pwq->pool->cpu;
58 ), 58 ),
59 59
60 TP_printk("work struct=%p function=%pf workqueue=%p req_cpu=%u cpu=%u", 60 TP_printk("work struct=%p function=%pf workqueue=%p req_cpu=%u cpu=%u",
diff --git a/kernel/async.c b/kernel/async.c
index 6f34904a0b53..6c68fc3fae7b 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -57,6 +57,8 @@ asynchronous and synchronous parts of the kernel.
57#include <linux/slab.h> 57#include <linux/slab.h>
58#include <linux/workqueue.h> 58#include <linux/workqueue.h>
59 59
60#include "workqueue_internal.h"
61
60static async_cookie_t next_cookie = 1; 62static async_cookie_t next_cookie = 1;
61 63
62#define MAX_WORK 32768 64#define MAX_WORK 32768
@@ -353,3 +355,15 @@ void async_synchronize_cookie(async_cookie_t cookie)
353 async_synchronize_cookie_domain(cookie, &async_running); 355 async_synchronize_cookie_domain(cookie, &async_running);
354} 356}
355EXPORT_SYMBOL_GPL(async_synchronize_cookie); 357EXPORT_SYMBOL_GPL(async_synchronize_cookie);
358
359/**
360 * current_is_async - is %current an async worker task?
361 *
362 * Returns %true if %current is an async worker task.
363 */
364bool current_is_async(void)
365{
366 struct worker *worker = current_wq_worker();
367
368 return worker && worker->current_func == async_run_entry_fn;
369}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4a88f1d51563..03d7784b7bd2 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -83,7 +83,7 @@
83#endif 83#endif
84 84
85#include "sched.h" 85#include "sched.h"
86#include "../workqueue_sched.h" 86#include "../workqueue_internal.h"
87#include "../smpboot.h" 87#include "../smpboot.h"
88 88
89#define CREATE_TRACE_POINTS 89#define CREATE_TRACE_POINTS
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index fbc6576a83c3..f4feacad3812 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -41,32 +41,31 @@
41#include <linux/debug_locks.h> 41#include <linux/debug_locks.h>
42#include <linux/lockdep.h> 42#include <linux/lockdep.h>
43#include <linux/idr.h> 43#include <linux/idr.h>
44#include <linux/hashtable.h>
44 45
45#include "workqueue_sched.h" 46#include "workqueue_internal.h"
46 47
47enum { 48enum {
48 /* 49 /*
49 * global_cwq flags 50 * worker_pool flags
50 * 51 *
51 * A bound gcwq is either associated or disassociated with its CPU. 52 * A bound pool is either associated or disassociated with its CPU.
52 * While associated (!DISASSOCIATED), all workers are bound to the 53 * While associated (!DISASSOCIATED), all workers are bound to the
53 * CPU and none has %WORKER_UNBOUND set and concurrency management 54 * CPU and none has %WORKER_UNBOUND set and concurrency management
54 * is in effect. 55 * is in effect.
55 * 56 *
56 * While DISASSOCIATED, the cpu may be offline and all workers have 57 * While DISASSOCIATED, the cpu may be offline and all workers have
57 * %WORKER_UNBOUND set and concurrency management disabled, and may 58 * %WORKER_UNBOUND set and concurrency management disabled, and may
58 * be executing on any CPU. The gcwq behaves as an unbound one. 59 * be executing on any CPU. The pool behaves as an unbound one.
59 * 60 *
60 * Note that DISASSOCIATED can be flipped only while holding 61 * Note that DISASSOCIATED can be flipped only while holding
61 * assoc_mutex of all pools on the gcwq to avoid changing binding 62 * assoc_mutex to avoid changing binding state while
62 * state while create_worker() is in progress. 63 * create_worker() is in progress.
63 */ 64 */
64 GCWQ_DISASSOCIATED = 1 << 0, /* cpu can't serve workers */
65 GCWQ_FREEZING = 1 << 1, /* freeze in progress */
66
67 /* pool flags */
68 POOL_MANAGE_WORKERS = 1 << 0, /* need to manage workers */ 65 POOL_MANAGE_WORKERS = 1 << 0, /* need to manage workers */
69 POOL_MANAGING_WORKERS = 1 << 1, /* managing workers */ 66 POOL_MANAGING_WORKERS = 1 << 1, /* managing workers */
67 POOL_DISASSOCIATED = 1 << 2, /* cpu can't serve workers */
68 POOL_FREEZING = 1 << 3, /* freeze in progress */
70 69
71 /* worker flags */ 70 /* worker flags */
72 WORKER_STARTED = 1 << 0, /* started */ 71 WORKER_STARTED = 1 << 0, /* started */
@@ -79,11 +78,9 @@ enum {
79 WORKER_NOT_RUNNING = WORKER_PREP | WORKER_UNBOUND | 78 WORKER_NOT_RUNNING = WORKER_PREP | WORKER_UNBOUND |
80 WORKER_CPU_INTENSIVE, 79 WORKER_CPU_INTENSIVE,
81 80
82 NR_WORKER_POOLS = 2, /* # worker pools per gcwq */ 81 NR_STD_WORKER_POOLS = 2, /* # standard pools per cpu */
83 82
84 BUSY_WORKER_HASH_ORDER = 6, /* 64 pointers */ 83 BUSY_WORKER_HASH_ORDER = 6, /* 64 pointers */
85 BUSY_WORKER_HASH_SIZE = 1 << BUSY_WORKER_HASH_ORDER,
86 BUSY_WORKER_HASH_MASK = BUSY_WORKER_HASH_SIZE - 1,
87 84
88 MAX_IDLE_WORKERS_RATIO = 4, /* 1/4 of busy can be idle */ 85 MAX_IDLE_WORKERS_RATIO = 4, /* 1/4 of busy can be idle */
89 IDLE_WORKER_TIMEOUT = 300 * HZ, /* keep idle ones for 5 mins */ 86 IDLE_WORKER_TIMEOUT = 300 * HZ, /* keep idle ones for 5 mins */
@@ -111,48 +108,24 @@ enum {
111 * P: Preemption protected. Disabling preemption is enough and should 108 * P: Preemption protected. Disabling preemption is enough and should
112 * only be modified and accessed from the local cpu. 109 * only be modified and accessed from the local cpu.
113 * 110 *
114 * L: gcwq->lock protected. Access with gcwq->lock held. 111 * L: pool->lock protected. Access with pool->lock held.
115 * 112 *
116 * X: During normal operation, modification requires gcwq->lock and 113 * X: During normal operation, modification requires pool->lock and should
117 * should be done only from local cpu. Either disabling preemption 114 * be done only from local cpu. Either disabling preemption on local
118 * on local cpu or grabbing gcwq->lock is enough for read access. 115 * cpu or grabbing pool->lock is enough for read access. If
119 * If GCWQ_DISASSOCIATED is set, it's identical to L. 116 * POOL_DISASSOCIATED is set, it's identical to L.
120 * 117 *
121 * F: wq->flush_mutex protected. 118 * F: wq->flush_mutex protected.
122 * 119 *
123 * W: workqueue_lock protected. 120 * W: workqueue_lock protected.
124 */ 121 */
125 122
126struct global_cwq; 123/* struct worker is defined in workqueue_internal.h */
127struct worker_pool;
128
129/*
130 * The poor guys doing the actual heavy lifting. All on-duty workers
131 * are either serving the manager role, on idle list or on busy hash.
132 */
133struct worker {
134 /* on idle list while idle, on busy hash table while busy */
135 union {
136 struct list_head entry; /* L: while idle */
137 struct hlist_node hentry; /* L: while busy */
138 };
139
140 struct work_struct *current_work; /* L: work being processed */
141 struct cpu_workqueue_struct *current_cwq; /* L: current_work's cwq */
142 struct list_head scheduled; /* L: scheduled works */
143 struct task_struct *task; /* I: worker task */
144 struct worker_pool *pool; /* I: the associated pool */
145 /* 64 bytes boundary on 64bit, 32 on 32bit */
146 unsigned long last_active; /* L: last active timestamp */
147 unsigned int flags; /* X: flags */
148 int id; /* I: worker id */
149
150 /* for rebinding worker to CPU */
151 struct work_struct rebind_work; /* L: for busy worker */
152};
153 124
154struct worker_pool { 125struct worker_pool {
155 struct global_cwq *gcwq; /* I: the owning gcwq */ 126 spinlock_t lock; /* the pool lock */
127 unsigned int cpu; /* I: the associated cpu */
128 int id; /* I: pool ID */
156 unsigned int flags; /* X: flags */ 129 unsigned int flags; /* X: flags */
157 130
158 struct list_head worklist; /* L: list of pending works */ 131 struct list_head worklist; /* L: list of pending works */
@@ -165,34 +138,28 @@ struct worker_pool {
165 struct timer_list idle_timer; /* L: worker idle timeout */ 138 struct timer_list idle_timer; /* L: worker idle timeout */
166 struct timer_list mayday_timer; /* L: SOS timer for workers */ 139 struct timer_list mayday_timer; /* L: SOS timer for workers */
167 140
168 struct mutex assoc_mutex; /* protect GCWQ_DISASSOCIATED */ 141 /* workers are chained either in busy_hash or idle_list */
169 struct ida worker_ida; /* L: for worker IDs */ 142 DECLARE_HASHTABLE(busy_hash, BUSY_WORKER_HASH_ORDER);
170};
171
172/*
173 * Global per-cpu workqueue. There's one and only one for each cpu
174 * and all works are queued and processed here regardless of their
175 * target workqueues.
176 */
177struct global_cwq {
178 spinlock_t lock; /* the gcwq lock */
179 unsigned int cpu; /* I: the associated cpu */
180 unsigned int flags; /* L: GCWQ_* flags */
181
182 /* workers are chained either in busy_hash or pool idle_list */
183 struct hlist_head busy_hash[BUSY_WORKER_HASH_SIZE];
184 /* L: hash of busy workers */ 143 /* L: hash of busy workers */
185 144
186 struct worker_pool pools[NR_WORKER_POOLS]; 145 struct mutex assoc_mutex; /* protect POOL_DISASSOCIATED */
187 /* normal and highpri pools */ 146 struct ida worker_ida; /* L: for worker IDs */
147
148 /*
149 * The current concurrency level. As it's likely to be accessed
150 * from other CPUs during try_to_wake_up(), put it in a separate
151 * cacheline.
152 */
153 atomic_t nr_running ____cacheline_aligned_in_smp;
188} ____cacheline_aligned_in_smp; 154} ____cacheline_aligned_in_smp;
189 155
190/* 156/*
191 * The per-CPU workqueue. The lower WORK_STRUCT_FLAG_BITS of 157 * The per-pool workqueue. While queued, the lower WORK_STRUCT_FLAG_BITS
192 * work_struct->data are used for flags and thus cwqs need to be 158 * of work_struct->data are used for flags and the remaining high bits
193 * aligned at two's power of the number of flag bits. 159 * point to the pwq; thus, pwqs need to be aligned at two's power of the
160 * number of flag bits.
194 */ 161 */
195struct cpu_workqueue_struct { 162struct pool_workqueue {
196 struct worker_pool *pool; /* I: the associated pool */ 163 struct worker_pool *pool; /* I: the associated pool */
197 struct workqueue_struct *wq; /* I: the owning workqueue */ 164 struct workqueue_struct *wq; /* I: the owning workqueue */
198 int work_color; /* L: current color */ 165 int work_color; /* L: current color */
@@ -241,16 +208,16 @@ typedef unsigned long mayday_mask_t;
241struct workqueue_struct { 208struct workqueue_struct {
242 unsigned int flags; /* W: WQ_* flags */ 209 unsigned int flags; /* W: WQ_* flags */
243 union { 210 union {
244 struct cpu_workqueue_struct __percpu *pcpu; 211 struct pool_workqueue __percpu *pcpu;
245 struct cpu_workqueue_struct *single; 212 struct pool_workqueue *single;
246 unsigned long v; 213 unsigned long v;
247 } cpu_wq; /* I: cwq's */ 214 } pool_wq; /* I: pwq's */
248 struct list_head list; /* W: list of all workqueues */ 215 struct list_head list; /* W: list of all workqueues */
249 216
250 struct mutex flush_mutex; /* protects wq flushing */ 217 struct mutex flush_mutex; /* protects wq flushing */
251 int work_color; /* F: current work color */ 218 int work_color; /* F: current work color */
252 int flush_color; /* F: current flush color */ 219 int flush_color; /* F: current flush color */
253 atomic_t nr_cwqs_to_flush; /* flush in progress */ 220 atomic_t nr_pwqs_to_flush; /* flush in progress */
254 struct wq_flusher *first_flusher; /* F: first flusher */ 221 struct wq_flusher *first_flusher; /* F: first flusher */
255 struct list_head flusher_queue; /* F: flush waiters */ 222 struct list_head flusher_queue; /* F: flush waiters */
256 struct list_head flusher_overflow; /* F: flush overflow list */ 223 struct list_head flusher_overflow; /* F: flush overflow list */
@@ -259,7 +226,7 @@ struct workqueue_struct {
259 struct worker *rescuer; /* I: rescue worker */ 226 struct worker *rescuer; /* I: rescue worker */
260 227
261 int nr_drainers; /* W: drain in progress */ 228 int nr_drainers; /* W: drain in progress */
262 int saved_max_active; /* W: saved cwq max_active */ 229 int saved_max_active; /* W: saved pwq max_active */
263#ifdef CONFIG_LOCKDEP 230#ifdef CONFIG_LOCKDEP
264 struct lockdep_map lockdep_map; 231 struct lockdep_map lockdep_map;
265#endif 232#endif
@@ -280,16 +247,15 @@ EXPORT_SYMBOL_GPL(system_freezable_wq);
280#define CREATE_TRACE_POINTS 247#define CREATE_TRACE_POINTS
281#include <trace/events/workqueue.h> 248#include <trace/events/workqueue.h>
282 249
283#define for_each_worker_pool(pool, gcwq) \ 250#define for_each_std_worker_pool(pool, cpu) \
284 for ((pool) = &(gcwq)->pools[0]; \ 251 for ((pool) = &std_worker_pools(cpu)[0]; \
285 (pool) < &(gcwq)->pools[NR_WORKER_POOLS]; (pool)++) 252 (pool) < &std_worker_pools(cpu)[NR_STD_WORKER_POOLS]; (pool)++)
286 253
287#define for_each_busy_worker(worker, i, pos, gcwq) \ 254#define for_each_busy_worker(worker, i, pos, pool) \
288 for (i = 0; i < BUSY_WORKER_HASH_SIZE; i++) \ 255 hash_for_each(pool->busy_hash, i, pos, worker, hentry)
289 hlist_for_each_entry(worker, pos, &gcwq->busy_hash[i], hentry)
290 256
291static inline int __next_gcwq_cpu(int cpu, const struct cpumask *mask, 257static inline int __next_wq_cpu(int cpu, const struct cpumask *mask,
292 unsigned int sw) 258 unsigned int sw)
293{ 259{
294 if (cpu < nr_cpu_ids) { 260 if (cpu < nr_cpu_ids) {
295 if (sw & 1) { 261 if (sw & 1) {
@@ -300,42 +266,42 @@ static inline int __next_gcwq_cpu(int cpu, const struct cpumask *mask,
300 if (sw & 2) 266 if (sw & 2)
301 return WORK_CPU_UNBOUND; 267 return WORK_CPU_UNBOUND;
302 } 268 }
303 return WORK_CPU_NONE; 269 return WORK_CPU_END;
304} 270}
305 271
306static inline int __next_wq_cpu(int cpu, const struct cpumask *mask, 272static inline int __next_pwq_cpu(int cpu, const struct cpumask *mask,
307 struct workqueue_struct *wq) 273 struct workqueue_struct *wq)
308{ 274{
309 return __next_gcwq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2); 275 return __next_wq_cpu(cpu, mask, !(wq->flags & WQ_UNBOUND) ? 1 : 2);
310} 276}
311 277
312/* 278/*
313 * CPU iterators 279 * CPU iterators
314 * 280 *
315 * An extra gcwq is defined for an invalid cpu number 281 * An extra cpu number is defined using an invalid cpu number
316 * (WORK_CPU_UNBOUND) to host workqueues which are not bound to any 282 * (WORK_CPU_UNBOUND) to host workqueues which are not bound to any
317 * specific CPU. The following iterators are similar to 283 * specific CPU. The following iterators are similar to for_each_*_cpu()
318 * for_each_*_cpu() iterators but also considers the unbound gcwq. 284 * iterators but also considers the unbound CPU.
319 * 285 *
320 * for_each_gcwq_cpu() : possible CPUs + WORK_CPU_UNBOUND 286 * for_each_wq_cpu() : possible CPUs + WORK_CPU_UNBOUND
321 * for_each_online_gcwq_cpu() : online CPUs + WORK_CPU_UNBOUND 287 * for_each_online_wq_cpu() : online CPUs + WORK_CPU_UNBOUND
322 * for_each_cwq_cpu() : possible CPUs for bound workqueues, 288 * for_each_pwq_cpu() : possible CPUs for bound workqueues,
323 * WORK_CPU_UNBOUND for unbound workqueues 289 * WORK_CPU_UNBOUND for unbound workqueues
324 */ 290 */
325#define for_each_gcwq_cpu(cpu) \ 291#define for_each_wq_cpu(cpu) \
326 for ((cpu) = __next_gcwq_cpu(-1, cpu_possible_mask, 3); \ 292 for ((cpu) = __next_wq_cpu(-1, cpu_possible_mask, 3); \
327 (cpu) < WORK_CPU_NONE; \ 293 (cpu) < WORK_CPU_END; \
328 (cpu) = __next_gcwq_cpu((cpu), cpu_possible_mask, 3)) 294 (cpu) = __next_wq_cpu((cpu), cpu_possible_mask, 3))
329 295
330#define for_each_online_gcwq_cpu(cpu) \ 296#define for_each_online_wq_cpu(cpu) \
331 for ((cpu) = __next_gcwq_cpu(-1, cpu_online_mask, 3); \ 297 for ((cpu) = __next_wq_cpu(-1, cpu_online_mask, 3); \
332 (cpu) < WORK_CPU_NONE; \ 298 (cpu) < WORK_CPU_END; \
333 (cpu) = __next_gcwq_cpu((cpu), cpu_online_mask, 3)) 299 (cpu) = __next_wq_cpu((cpu), cpu_online_mask, 3))
334 300
335#define for_each_cwq_cpu(cpu, wq) \ 301#define for_each_pwq_cpu(cpu, wq) \
336 for ((cpu) = __next_wq_cpu(-1, cpu_possible_mask, (wq)); \ 302 for ((cpu) = __next_pwq_cpu(-1, cpu_possible_mask, (wq)); \
337 (cpu) < WORK_CPU_NONE; \ 303 (cpu) < WORK_CPU_END; \
338 (cpu) = __next_wq_cpu((cpu), cpu_possible_mask, (wq))) 304 (cpu) = __next_pwq_cpu((cpu), cpu_possible_mask, (wq)))
339 305
340#ifdef CONFIG_DEBUG_OBJECTS_WORK 306#ifdef CONFIG_DEBUG_OBJECTS_WORK
341 307
@@ -459,57 +425,69 @@ static LIST_HEAD(workqueues);
459static bool workqueue_freezing; /* W: have wqs started freezing? */ 425static bool workqueue_freezing; /* W: have wqs started freezing? */
460 426
461/* 427/*
462 * The almighty global cpu workqueues. nr_running is the only field 428 * The CPU and unbound standard worker pools. The unbound ones have
463 * which is expected to be used frequently by other cpus via 429 * POOL_DISASSOCIATED set, and their workers have WORKER_UNBOUND set.
464 * try_to_wake_up(). Put it in a separate cacheline.
465 */ 430 */
466static DEFINE_PER_CPU(struct global_cwq, global_cwq); 431static DEFINE_PER_CPU_SHARED_ALIGNED(struct worker_pool [NR_STD_WORKER_POOLS],
467static DEFINE_PER_CPU_SHARED_ALIGNED(atomic_t, pool_nr_running[NR_WORKER_POOLS]); 432 cpu_std_worker_pools);
433static struct worker_pool unbound_std_worker_pools[NR_STD_WORKER_POOLS];
468 434
469/* 435/* idr of all pools */
470 * Global cpu workqueue and nr_running counter for unbound gcwq. The 436static DEFINE_MUTEX(worker_pool_idr_mutex);
471 * gcwq is always online, has GCWQ_DISASSOCIATED set, and all its 437static DEFINE_IDR(worker_pool_idr);
472 * workers have WORKER_UNBOUND set.
473 */
474static struct global_cwq unbound_global_cwq;
475static atomic_t unbound_pool_nr_running[NR_WORKER_POOLS] = {
476 [0 ... NR_WORKER_POOLS - 1] = ATOMIC_INIT(0), /* always 0 */
477};
478 438
479static int worker_thread(void *__worker); 439static int worker_thread(void *__worker);
480 440
481static int worker_pool_pri(struct worker_pool *pool) 441static struct worker_pool *std_worker_pools(int cpu)
482{ 442{
483 return pool - pool->gcwq->pools; 443 if (cpu != WORK_CPU_UNBOUND)
444 return per_cpu(cpu_std_worker_pools, cpu);
445 else
446 return unbound_std_worker_pools;
484} 447}
485 448
486static struct global_cwq *get_gcwq(unsigned int cpu) 449static int std_worker_pool_pri(struct worker_pool *pool)
487{ 450{
488 if (cpu != WORK_CPU_UNBOUND) 451 return pool - std_worker_pools(pool->cpu);
489 return &per_cpu(global_cwq, cpu);
490 else
491 return &unbound_global_cwq;
492} 452}
493 453
494static atomic_t *get_pool_nr_running(struct worker_pool *pool) 454/* allocate ID and assign it to @pool */
455static int worker_pool_assign_id(struct worker_pool *pool)
495{ 456{
496 int cpu = pool->gcwq->cpu; 457 int ret;
497 int idx = worker_pool_pri(pool);
498 458
499 if (cpu != WORK_CPU_UNBOUND) 459 mutex_lock(&worker_pool_idr_mutex);
500 return &per_cpu(pool_nr_running, cpu)[idx]; 460 idr_pre_get(&worker_pool_idr, GFP_KERNEL);
501 else 461 ret = idr_get_new(&worker_pool_idr, pool, &pool->id);
502 return &unbound_pool_nr_running[idx]; 462 mutex_unlock(&worker_pool_idr_mutex);
463
464 return ret;
503} 465}
504 466
505static struct cpu_workqueue_struct *get_cwq(unsigned int cpu, 467/*
506 struct workqueue_struct *wq) 468 * Lookup worker_pool by id. The idr currently is built during boot and
469 * never modified. Don't worry about locking for now.
470 */
471static struct worker_pool *worker_pool_by_id(int pool_id)
472{
473 return idr_find(&worker_pool_idr, pool_id);
474}
475
476static struct worker_pool *get_std_worker_pool(int cpu, bool highpri)
477{
478 struct worker_pool *pools = std_worker_pools(cpu);
479
480 return &pools[highpri];
481}
482
483static struct pool_workqueue *get_pwq(unsigned int cpu,
484 struct workqueue_struct *wq)
507{ 485{
508 if (!(wq->flags & WQ_UNBOUND)) { 486 if (!(wq->flags & WQ_UNBOUND)) {
509 if (likely(cpu < nr_cpu_ids)) 487 if (likely(cpu < nr_cpu_ids))
510 return per_cpu_ptr(wq->cpu_wq.pcpu, cpu); 488 return per_cpu_ptr(wq->pool_wq.pcpu, cpu);
511 } else if (likely(cpu == WORK_CPU_UNBOUND)) 489 } else if (likely(cpu == WORK_CPU_UNBOUND))
512 return wq->cpu_wq.single; 490 return wq->pool_wq.single;
513 return NULL; 491 return NULL;
514} 492}
515 493
@@ -530,19 +508,19 @@ static int work_next_color(int color)
530} 508}
531 509
532/* 510/*
533 * While queued, %WORK_STRUCT_CWQ is set and non flag bits of a work's data 511 * While queued, %WORK_STRUCT_PWQ is set and non flag bits of a work's data
534 * contain the pointer to the queued cwq. Once execution starts, the flag 512 * contain the pointer to the queued pwq. Once execution starts, the flag
535 * is cleared and the high bits contain OFFQ flags and CPU number. 513 * is cleared and the high bits contain OFFQ flags and pool ID.
536 * 514 *
537 * set_work_cwq(), set_work_cpu_and_clear_pending(), mark_work_canceling() 515 * set_work_pwq(), set_work_pool_and_clear_pending(), mark_work_canceling()
538 * and clear_work_data() can be used to set the cwq, cpu or clear 516 * and clear_work_data() can be used to set the pwq, pool or clear
539 * work->data. These functions should only be called while the work is 517 * work->data. These functions should only be called while the work is
540 * owned - ie. while the PENDING bit is set. 518 * owned - ie. while the PENDING bit is set.
541 * 519 *
542 * get_work_[g]cwq() can be used to obtain the gcwq or cwq corresponding to 520 * get_work_pool() and get_work_pwq() can be used to obtain the pool or pwq
543 * a work. gcwq is available once the work has been queued anywhere after 521 * corresponding to a work. Pool is available once the work has been
544 * initialization until it is sync canceled. cwq is available only while 522 * queued anywhere after initialization until it is sync canceled. pwq is
545 * the work item is queued. 523 * available only while the work item is queued.
546 * 524 *
547 * %WORK_OFFQ_CANCELING is used to mark a work item which is being 525 * %WORK_OFFQ_CANCELING is used to mark a work item which is being
548 * canceled. While being canceled, a work item may have its PENDING set 526 * canceled. While being canceled, a work item may have its PENDING set
@@ -556,16 +534,22 @@ static inline void set_work_data(struct work_struct *work, unsigned long data,
556 atomic_long_set(&work->data, data | flags | work_static(work)); 534 atomic_long_set(&work->data, data | flags | work_static(work));
557} 535}
558 536
559static void set_work_cwq(struct work_struct *work, 537static void set_work_pwq(struct work_struct *work, struct pool_workqueue *pwq,
560 struct cpu_workqueue_struct *cwq,
561 unsigned long extra_flags) 538 unsigned long extra_flags)
562{ 539{
563 set_work_data(work, (unsigned long)cwq, 540 set_work_data(work, (unsigned long)pwq,
564 WORK_STRUCT_PENDING | WORK_STRUCT_CWQ | extra_flags); 541 WORK_STRUCT_PENDING | WORK_STRUCT_PWQ | extra_flags);
565} 542}
566 543
567static void set_work_cpu_and_clear_pending(struct work_struct *work, 544static void set_work_pool_and_keep_pending(struct work_struct *work,
568 unsigned int cpu) 545 int pool_id)
546{
547 set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT,
548 WORK_STRUCT_PENDING);
549}
550
551static void set_work_pool_and_clear_pending(struct work_struct *work,
552 int pool_id)
569{ 553{
570 /* 554 /*
571 * The following wmb is paired with the implied mb in 555 * The following wmb is paired with the implied mb in
@@ -574,67 +558,92 @@ static void set_work_cpu_and_clear_pending(struct work_struct *work,
574 * owner. 558 * owner.
575 */ 559 */
576 smp_wmb(); 560 smp_wmb();
577 set_work_data(work, (unsigned long)cpu << WORK_OFFQ_CPU_SHIFT, 0); 561 set_work_data(work, (unsigned long)pool_id << WORK_OFFQ_POOL_SHIFT, 0);
578} 562}
579 563
580static void clear_work_data(struct work_struct *work) 564static void clear_work_data(struct work_struct *work)
581{ 565{
582 smp_wmb(); /* see set_work_cpu_and_clear_pending() */ 566 smp_wmb(); /* see set_work_pool_and_clear_pending() */
583 set_work_data(work, WORK_STRUCT_NO_CPU, 0); 567 set_work_data(work, WORK_STRUCT_NO_POOL, 0);
584} 568}
585 569
586static struct cpu_workqueue_struct *get_work_cwq(struct work_struct *work) 570static struct pool_workqueue *get_work_pwq(struct work_struct *work)
587{ 571{
588 unsigned long data = atomic_long_read(&work->data); 572 unsigned long data = atomic_long_read(&work->data);
589 573
590 if (data & WORK_STRUCT_CWQ) 574 if (data & WORK_STRUCT_PWQ)
591 return (void *)(data & WORK_STRUCT_WQ_DATA_MASK); 575 return (void *)(data & WORK_STRUCT_WQ_DATA_MASK);
592 else 576 else
593 return NULL; 577 return NULL;
594} 578}
595 579
596static struct global_cwq *get_work_gcwq(struct work_struct *work) 580/**
581 * get_work_pool - return the worker_pool a given work was associated with
582 * @work: the work item of interest
583 *
584 * Return the worker_pool @work was last associated with. %NULL if none.
585 */
586static struct worker_pool *get_work_pool(struct work_struct *work)
597{ 587{
598 unsigned long data = atomic_long_read(&work->data); 588 unsigned long data = atomic_long_read(&work->data);
599 unsigned int cpu; 589 struct worker_pool *pool;
590 int pool_id;
600 591
601 if (data & WORK_STRUCT_CWQ) 592 if (data & WORK_STRUCT_PWQ)
602 return ((struct cpu_workqueue_struct *) 593 return ((struct pool_workqueue *)
603 (data & WORK_STRUCT_WQ_DATA_MASK))->pool->gcwq; 594 (data & WORK_STRUCT_WQ_DATA_MASK))->pool;
604 595
605 cpu = data >> WORK_OFFQ_CPU_SHIFT; 596 pool_id = data >> WORK_OFFQ_POOL_SHIFT;
606 if (cpu == WORK_CPU_NONE) 597 if (pool_id == WORK_OFFQ_POOL_NONE)
607 return NULL; 598 return NULL;
608 599
609 BUG_ON(cpu >= nr_cpu_ids && cpu != WORK_CPU_UNBOUND); 600 pool = worker_pool_by_id(pool_id);
610 return get_gcwq(cpu); 601 WARN_ON_ONCE(!pool);
602 return pool;
603}
604
605/**
606 * get_work_pool_id - return the worker pool ID a given work is associated with
607 * @work: the work item of interest
608 *
609 * Return the worker_pool ID @work was last associated with.
610 * %WORK_OFFQ_POOL_NONE if none.
611 */
612static int get_work_pool_id(struct work_struct *work)
613{
614 unsigned long data = atomic_long_read(&work->data);
615
616 if (data & WORK_STRUCT_PWQ)
617 return ((struct pool_workqueue *)
618 (data & WORK_STRUCT_WQ_DATA_MASK))->pool->id;
619
620 return data >> WORK_OFFQ_POOL_SHIFT;
611} 621}
612 622
613static void mark_work_canceling(struct work_struct *work) 623static void mark_work_canceling(struct work_struct *work)
614{ 624{
615 struct global_cwq *gcwq = get_work_gcwq(work); 625 unsigned long pool_id = get_work_pool_id(work);
616 unsigned long cpu = gcwq ? gcwq->cpu : WORK_CPU_NONE;
617 626
618 set_work_data(work, (cpu << WORK_OFFQ_CPU_SHIFT) | WORK_OFFQ_CANCELING, 627 pool_id <<= WORK_OFFQ_POOL_SHIFT;
619 WORK_STRUCT_PENDING); 628 set_work_data(work, pool_id | WORK_OFFQ_CANCELING, WORK_STRUCT_PENDING);
620} 629}
621 630
622static bool work_is_canceling(struct work_struct *work) 631static bool work_is_canceling(struct work_struct *work)
623{ 632{
624 unsigned long data = atomic_long_read(&work->data); 633 unsigned long data = atomic_long_read(&work->data);
625 634
626 return !(data & WORK_STRUCT_CWQ) && (data & WORK_OFFQ_CANCELING); 635 return !(data & WORK_STRUCT_PWQ) && (data & WORK_OFFQ_CANCELING);
627} 636}
628 637
629/* 638/*
630 * Policy functions. These define the policies on how the global worker 639 * Policy functions. These define the policies on how the global worker
631 * pools are managed. Unless noted otherwise, these functions assume that 640 * pools are managed. Unless noted otherwise, these functions assume that
632 * they're being called with gcwq->lock held. 641 * they're being called with pool->lock held.
633 */ 642 */
634 643
635static bool __need_more_worker(struct worker_pool *pool) 644static bool __need_more_worker(struct worker_pool *pool)
636{ 645{
637 return !atomic_read(get_pool_nr_running(pool)); 646 return !atomic_read(&pool->nr_running);
638} 647}
639 648
640/* 649/*
@@ -642,7 +651,7 @@ static bool __need_more_worker(struct worker_pool *pool)
642 * running workers. 651 * running workers.
643 * 652 *
644 * Note that, because unbound workers never contribute to nr_running, this 653 * Note that, because unbound workers never contribute to nr_running, this
645 * function will always return %true for unbound gcwq as long as the 654 * function will always return %true for unbound pools as long as the
646 * worklist isn't empty. 655 * worklist isn't empty.
647 */ 656 */
648static bool need_more_worker(struct worker_pool *pool) 657static bool need_more_worker(struct worker_pool *pool)
@@ -659,9 +668,8 @@ static bool may_start_working(struct worker_pool *pool)
659/* Do I need to keep working? Called from currently running workers. */ 668/* Do I need to keep working? Called from currently running workers. */
660static bool keep_working(struct worker_pool *pool) 669static bool keep_working(struct worker_pool *pool)
661{ 670{
662 atomic_t *nr_running = get_pool_nr_running(pool); 671 return !list_empty(&pool->worklist) &&
663 672 atomic_read(&pool->nr_running) <= 1;
664 return !list_empty(&pool->worklist) && atomic_read(nr_running) <= 1;
665} 673}
666 674
667/* Do we need a new worker? Called from manager. */ 675/* Do we need a new worker? Called from manager. */
@@ -714,7 +722,7 @@ static struct worker *first_worker(struct worker_pool *pool)
714 * Wake up the first idle worker of @pool. 722 * Wake up the first idle worker of @pool.
715 * 723 *
716 * CONTEXT: 724 * CONTEXT:
717 * spin_lock_irq(gcwq->lock). 725 * spin_lock_irq(pool->lock).
718 */ 726 */
719static void wake_up_worker(struct worker_pool *pool) 727static void wake_up_worker(struct worker_pool *pool)
720{ 728{
@@ -740,8 +748,8 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu)
740 struct worker *worker = kthread_data(task); 748 struct worker *worker = kthread_data(task);
741 749
742 if (!(worker->flags & WORKER_NOT_RUNNING)) { 750 if (!(worker->flags & WORKER_NOT_RUNNING)) {
743 WARN_ON_ONCE(worker->pool->gcwq->cpu != cpu); 751 WARN_ON_ONCE(worker->pool->cpu != cpu);
744 atomic_inc(get_pool_nr_running(worker->pool)); 752 atomic_inc(&worker->pool->nr_running);
745 } 753 }
746} 754}
747 755
@@ -764,12 +772,18 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
764 unsigned int cpu) 772 unsigned int cpu)
765{ 773{
766 struct worker *worker = kthread_data(task), *to_wakeup = NULL; 774 struct worker *worker = kthread_data(task), *to_wakeup = NULL;
767 struct worker_pool *pool = worker->pool; 775 struct worker_pool *pool;
768 atomic_t *nr_running = get_pool_nr_running(pool);
769 776
777 /*
778 * Rescuers, which may not have all the fields set up like normal
779 * workers, also reach here, let's not access anything before
780 * checking NOT_RUNNING.
781 */
770 if (worker->flags & WORKER_NOT_RUNNING) 782 if (worker->flags & WORKER_NOT_RUNNING)
771 return NULL; 783 return NULL;
772 784
785 pool = worker->pool;
786
773 /* this can only happen on the local cpu */ 787 /* this can only happen on the local cpu */
774 BUG_ON(cpu != raw_smp_processor_id()); 788 BUG_ON(cpu != raw_smp_processor_id());
775 789
@@ -781,10 +795,11 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
781 * NOT_RUNNING is clear. This means that we're bound to and 795 * NOT_RUNNING is clear. This means that we're bound to and
782 * running on the local cpu w/ rq lock held and preemption 796 * running on the local cpu w/ rq lock held and preemption
783 * disabled, which in turn means that none else could be 797 * disabled, which in turn means that none else could be
784 * manipulating idle_list, so dereferencing idle_list without gcwq 798 * manipulating idle_list, so dereferencing idle_list without pool
785 * lock is safe. 799 * lock is safe.
786 */ 800 */
787 if (atomic_dec_and_test(nr_running) && !list_empty(&pool->worklist)) 801 if (atomic_dec_and_test(&pool->nr_running) &&
802 !list_empty(&pool->worklist))
788 to_wakeup = first_worker(pool); 803 to_wakeup = first_worker(pool);
789 return to_wakeup ? to_wakeup->task : NULL; 804 return to_wakeup ? to_wakeup->task : NULL;
790} 805}
@@ -800,7 +815,7 @@ struct task_struct *wq_worker_sleeping(struct task_struct *task,
800 * woken up. 815 * woken up.
801 * 816 *
802 * CONTEXT: 817 * CONTEXT:
803 * spin_lock_irq(gcwq->lock) 818 * spin_lock_irq(pool->lock)
804 */ 819 */
805static inline void worker_set_flags(struct worker *worker, unsigned int flags, 820static inline void worker_set_flags(struct worker *worker, unsigned int flags,
806 bool wakeup) 821 bool wakeup)
@@ -816,14 +831,12 @@ static inline void worker_set_flags(struct worker *worker, unsigned int flags,
816 */ 831 */
817 if ((flags & WORKER_NOT_RUNNING) && 832 if ((flags & WORKER_NOT_RUNNING) &&
818 !(worker->flags & WORKER_NOT_RUNNING)) { 833 !(worker->flags & WORKER_NOT_RUNNING)) {
819 atomic_t *nr_running = get_pool_nr_running(pool);
820
821 if (wakeup) { 834 if (wakeup) {
822 if (atomic_dec_and_test(nr_running) && 835 if (atomic_dec_and_test(&pool->nr_running) &&
823 !list_empty(&pool->worklist)) 836 !list_empty(&pool->worklist))
824 wake_up_worker(pool); 837 wake_up_worker(pool);
825 } else 838 } else
826 atomic_dec(nr_running); 839 atomic_dec(&pool->nr_running);
827 } 840 }
828 841
829 worker->flags |= flags; 842 worker->flags |= flags;
@@ -837,7 +850,7 @@ static inline void worker_set_flags(struct worker *worker, unsigned int flags,
837 * Clear @flags in @worker->flags and adjust nr_running accordingly. 850 * Clear @flags in @worker->flags and adjust nr_running accordingly.
838 * 851 *
839 * CONTEXT: 852 * CONTEXT:
840 * spin_lock_irq(gcwq->lock) 853 * spin_lock_irq(pool->lock)
841 */ 854 */
842static inline void worker_clr_flags(struct worker *worker, unsigned int flags) 855static inline void worker_clr_flags(struct worker *worker, unsigned int flags)
843{ 856{
@@ -855,87 +868,56 @@ static inline void worker_clr_flags(struct worker *worker, unsigned int flags)
855 */ 868 */
856 if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING)) 869 if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING))
857 if (!(worker->flags & WORKER_NOT_RUNNING)) 870 if (!(worker->flags & WORKER_NOT_RUNNING))
858 atomic_inc(get_pool_nr_running(pool)); 871 atomic_inc(&pool->nr_running);
859} 872}
860 873
861/** 874/**
862 * busy_worker_head - return the busy hash head for a work 875 * find_worker_executing_work - find worker which is executing a work
863 * @gcwq: gcwq of interest 876 * @pool: pool of interest
864 * @work: work to be hashed
865 *
866 * Return hash head of @gcwq for @work.
867 *
868 * CONTEXT:
869 * spin_lock_irq(gcwq->lock).
870 *
871 * RETURNS:
872 * Pointer to the hash head.
873 */
874static struct hlist_head *busy_worker_head(struct global_cwq *gcwq,
875 struct work_struct *work)
876{
877 const int base_shift = ilog2(sizeof(struct work_struct));
878 unsigned long v = (unsigned long)work;
879
880 /* simple shift and fold hash, do we need something better? */
881 v >>= base_shift;
882 v += v >> BUSY_WORKER_HASH_ORDER;
883 v &= BUSY_WORKER_HASH_MASK;
884
885 return &gcwq->busy_hash[v];
886}
887
888/**
889 * __find_worker_executing_work - find worker which is executing a work
890 * @gcwq: gcwq of interest
891 * @bwh: hash head as returned by busy_worker_head()
892 * @work: work to find worker for 877 * @work: work to find worker for
893 * 878 *
894 * Find a worker which is executing @work on @gcwq. @bwh should be 879 * Find a worker which is executing @work on @pool by searching
895 * the hash head obtained by calling busy_worker_head() with the same 880 * @pool->busy_hash which is keyed by the address of @work. For a worker
896 * work. 881 * to match, its current execution should match the address of @work and
882 * its work function. This is to avoid unwanted dependency between
883 * unrelated work executions through a work item being recycled while still
884 * being executed.
885 *
886 * This is a bit tricky. A work item may be freed once its execution
887 * starts and nothing prevents the freed area from being recycled for
888 * another work item. If the same work item address ends up being reused
889 * before the original execution finishes, workqueue will identify the
890 * recycled work item as currently executing and make it wait until the
891 * current execution finishes, introducing an unwanted dependency.
892 *
893 * This function checks the work item address, work function and workqueue
894 * to avoid false positives. Note that this isn't complete as one may
895 * construct a work function which can introduce dependency onto itself
896 * through a recycled work item. Well, if somebody wants to shoot oneself
897 * in the foot that badly, there's only so much we can do, and if such
898 * deadlock actually occurs, it should be easy to locate the culprit work
899 * function.
897 * 900 *
898 * CONTEXT: 901 * CONTEXT:
899 * spin_lock_irq(gcwq->lock). 902 * spin_lock_irq(pool->lock).
900 * 903 *
901 * RETURNS: 904 * RETURNS:
902 * Pointer to worker which is executing @work if found, NULL 905 * Pointer to worker which is executing @work if found, NULL
903 * otherwise. 906 * otherwise.
904 */ 907 */
905static struct worker *__find_worker_executing_work(struct global_cwq *gcwq, 908static struct worker *find_worker_executing_work(struct worker_pool *pool,
906 struct hlist_head *bwh, 909 struct work_struct *work)
907 struct work_struct *work)
908{ 910{
909 struct worker *worker; 911 struct worker *worker;
910 struct hlist_node *tmp; 912 struct hlist_node *tmp;
911 913
912 hlist_for_each_entry(worker, tmp, bwh, hentry) 914 hash_for_each_possible(pool->busy_hash, worker, tmp, hentry,
913 if (worker->current_work == work) 915 (unsigned long)work)
916 if (worker->current_work == work &&
917 worker->current_func == work->func)
914 return worker; 918 return worker;
915 return NULL;
916}
917 919
918/** 920 return NULL;
919 * find_worker_executing_work - find worker which is executing a work
920 * @gcwq: gcwq of interest
921 * @work: work to find worker for
922 *
923 * Find a worker which is executing @work on @gcwq. This function is
924 * identical to __find_worker_executing_work() except that this
925 * function calculates @bwh itself.
926 *
927 * CONTEXT:
928 * spin_lock_irq(gcwq->lock).
929 *
930 * RETURNS:
931 * Pointer to worker which is executing @work if found, NULL
932 * otherwise.
933 */
934static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
935 struct work_struct *work)
936{
937 return __find_worker_executing_work(gcwq, busy_worker_head(gcwq, work),
938 work);
939} 921}
940 922
941/** 923/**
@@ -953,7 +935,7 @@ static struct worker *find_worker_executing_work(struct global_cwq *gcwq,
953 * nested inside outer list_for_each_entry_safe(). 935 * nested inside outer list_for_each_entry_safe().
954 * 936 *
955 * CONTEXT: 937 * CONTEXT:
956 * spin_lock_irq(gcwq->lock). 938 * spin_lock_irq(pool->lock).
957 */ 939 */
958static void move_linked_works(struct work_struct *work, struct list_head *head, 940static void move_linked_works(struct work_struct *work, struct list_head *head,
959 struct work_struct **nextp) 941 struct work_struct **nextp)
@@ -979,67 +961,67 @@ static void move_linked_works(struct work_struct *work, struct list_head *head,
979 *nextp = n; 961 *nextp = n;
980} 962}
981 963
982static void cwq_activate_delayed_work(struct work_struct *work) 964static void pwq_activate_delayed_work(struct work_struct *work)
983{ 965{
984 struct cpu_workqueue_struct *cwq = get_work_cwq(work); 966 struct pool_workqueue *pwq = get_work_pwq(work);
985 967
986 trace_workqueue_activate_work(work); 968 trace_workqueue_activate_work(work);
987 move_linked_works(work, &cwq->pool->worklist, NULL); 969 move_linked_works(work, &pwq->pool->worklist, NULL);
988 __clear_bit(WORK_STRUCT_DELAYED_BIT, work_data_bits(work)); 970 __clear_bit(WORK_STRUCT_DELAYED_BIT, work_data_bits(work));
989 cwq->nr_active++; 971 pwq->nr_active++;
990} 972}
991 973
992static void cwq_activate_first_delayed(struct cpu_workqueue_struct *cwq) 974static void pwq_activate_first_delayed(struct pool_workqueue *pwq)
993{ 975{
994 struct work_struct *work = list_first_entry(&cwq->delayed_works, 976 struct work_struct *work = list_first_entry(&pwq->delayed_works,
995 struct work_struct, entry); 977 struct work_struct, entry);
996 978
997 cwq_activate_delayed_work(work); 979 pwq_activate_delayed_work(work);
998} 980}
999 981
1000/** 982/**
1001 * cwq_dec_nr_in_flight - decrement cwq's nr_in_flight 983 * pwq_dec_nr_in_flight - decrement pwq's nr_in_flight
1002 * @cwq: cwq of interest 984 * @pwq: pwq of interest
1003 * @color: color of work which left the queue 985 * @color: color of work which left the queue
1004 * 986 *
1005 * A work either has completed or is removed from pending queue, 987 * A work either has completed or is removed from pending queue,
1006 * decrement nr_in_flight of its cwq and handle workqueue flushing. 988 * decrement nr_in_flight of its pwq and handle workqueue flushing.
1007 * 989 *
1008 * CONTEXT: 990 * CONTEXT:
1009 * spin_lock_irq(gcwq->lock). 991 * spin_lock_irq(pool->lock).
1010 */ 992 */
1011static void cwq_dec_nr_in_flight(struct cpu_workqueue_struct *cwq, int color) 993static void pwq_dec_nr_in_flight(struct pool_workqueue *pwq, int color)
1012{ 994{
1013 /* ignore uncolored works */ 995 /* ignore uncolored works */
1014 if (color == WORK_NO_COLOR) 996 if (color == WORK_NO_COLOR)
1015 return; 997 return;
1016 998
1017 cwq->nr_in_flight[color]--; 999 pwq->nr_in_flight[color]--;
1018 1000
1019 cwq->nr_active--; 1001 pwq->nr_active--;
1020 if (!list_empty(&cwq->delayed_works)) { 1002 if (!list_empty(&pwq->delayed_works)) {
1021 /* one down, submit a delayed one */ 1003 /* one down, submit a delayed one */
1022 if (cwq->nr_active < cwq->max_active) 1004 if (pwq->nr_active < pwq->max_active)
1023 cwq_activate_first_delayed(cwq); 1005 pwq_activate_first_delayed(pwq);
1024 } 1006 }
1025 1007
1026 /* is flush in progress and are we at the flushing tip? */ 1008 /* is flush in progress and are we at the flushing tip? */
1027 if (likely(cwq->flush_color != color)) 1009 if (likely(pwq->flush_color != color))
1028 return; 1010 return;
1029 1011
1030 /* are there still in-flight works? */ 1012 /* are there still in-flight works? */
1031 if (cwq->nr_in_flight[color]) 1013 if (pwq->nr_in_flight[color])
1032 return; 1014 return;
1033 1015
1034 /* this cwq is done, clear flush_color */ 1016 /* this pwq is done, clear flush_color */
1035 cwq->flush_color = -1; 1017 pwq->flush_color = -1;
1036 1018
1037 /* 1019 /*
1038 * If this was the last cwq, wake up the first flusher. It 1020 * If this was the last pwq, wake up the first flusher. It
1039 * will handle the rest. 1021 * will handle the rest.
1040 */ 1022 */
1041 if (atomic_dec_and_test(&cwq->wq->nr_cwqs_to_flush)) 1023 if (atomic_dec_and_test(&pwq->wq->nr_pwqs_to_flush))
1042 complete(&cwq->wq->first_flusher->done); 1024 complete(&pwq->wq->first_flusher->done);
1043} 1025}
1044 1026
1045/** 1027/**
@@ -1070,7 +1052,8 @@ static void cwq_dec_nr_in_flight(struct cpu_workqueue_struct *cwq, int color)
1070static int try_to_grab_pending(struct work_struct *work, bool is_dwork, 1052static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
1071 unsigned long *flags) 1053 unsigned long *flags)
1072{ 1054{
1073 struct global_cwq *gcwq; 1055 struct worker_pool *pool;
1056 struct pool_workqueue *pwq;
1074 1057
1075 local_irq_save(*flags); 1058 local_irq_save(*flags);
1076 1059
@@ -1095,41 +1078,43 @@ static int try_to_grab_pending(struct work_struct *work, bool is_dwork,
1095 * The queueing is in progress, or it is already queued. Try to 1078 * The queueing is in progress, or it is already queued. Try to
1096 * steal it from ->worklist without clearing WORK_STRUCT_PENDING. 1079 * steal it from ->worklist without clearing WORK_STRUCT_PENDING.
1097 */ 1080 */
1098 gcwq = get_work_gcwq(work); 1081 pool = get_work_pool(work);
1099 if (!gcwq) 1082 if (!pool)
1100 goto fail; 1083 goto fail;
1101 1084
1102 spin_lock(&gcwq->lock); 1085 spin_lock(&pool->lock);
1103 if (!list_empty(&work->entry)) { 1086 /*
1087 * work->data is guaranteed to point to pwq only while the work
1088 * item is queued on pwq->wq, and both updating work->data to point
1089 * to pwq on queueing and to pool on dequeueing are done under
1090 * pwq->pool->lock. This in turn guarantees that, if work->data
1091 * points to pwq which is associated with a locked pool, the work
1092 * item is currently queued on that pool.
1093 */
1094 pwq = get_work_pwq(work);
1095 if (pwq && pwq->pool == pool) {
1096 debug_work_deactivate(work);
1097
1104 /* 1098 /*
1105 * This work is queued, but perhaps we locked the wrong gcwq. 1099 * A delayed work item cannot be grabbed directly because
1106 * In that case we must see the new value after rmb(), see 1100 * it might have linked NO_COLOR work items which, if left
1107 * insert_work()->wmb(). 1101 * on the delayed_list, will confuse pwq->nr_active
1102 * management later on and cause stall. Make sure the work
1103 * item is activated before grabbing.
1108 */ 1104 */
1109 smp_rmb(); 1105 if (*work_data_bits(work) & WORK_STRUCT_DELAYED)
1110 if (gcwq == get_work_gcwq(work)) { 1106 pwq_activate_delayed_work(work);
1111 debug_work_deactivate(work);
1112 1107
1113 /* 1108 list_del_init(&work->entry);
1114 * A delayed work item cannot be grabbed directly 1109 pwq_dec_nr_in_flight(get_work_pwq(work), get_work_color(work));
1115 * because it might have linked NO_COLOR work items
1116 * which, if left on the delayed_list, will confuse
1117 * cwq->nr_active management later on and cause
1118 * stall. Make sure the work item is activated
1119 * before grabbing.
1120 */
1121 if (*work_data_bits(work) & WORK_STRUCT_DELAYED)
1122 cwq_activate_delayed_work(work);
1123 1110
1124 list_del_init(&work->entry); 1111 /* work->data points to pwq iff queued, point to pool */
1125 cwq_dec_nr_in_flight(get_work_cwq(work), 1112 set_work_pool_and_keep_pending(work, pool->id);
1126 get_work_color(work));
1127 1113
1128 spin_unlock(&gcwq->lock); 1114 spin_unlock(&pool->lock);
1129 return 1; 1115 return 1;
1130 }
1131 } 1116 }
1132 spin_unlock(&gcwq->lock); 1117 spin_unlock(&pool->lock);
1133fail: 1118fail:
1134 local_irq_restore(*flags); 1119 local_irq_restore(*flags);
1135 if (work_is_canceling(work)) 1120 if (work_is_canceling(work))
@@ -1139,33 +1124,25 @@ fail:
1139} 1124}
1140 1125
1141/** 1126/**
1142 * insert_work - insert a work into gcwq 1127 * insert_work - insert a work into a pool
1143 * @cwq: cwq @work belongs to 1128 * @pwq: pwq @work belongs to
1144 * @work: work to insert 1129 * @work: work to insert
1145 * @head: insertion point 1130 * @head: insertion point
1146 * @extra_flags: extra WORK_STRUCT_* flags to set 1131 * @extra_flags: extra WORK_STRUCT_* flags to set
1147 * 1132 *
1148 * Insert @work which belongs to @cwq into @gcwq after @head. 1133 * Insert @work which belongs to @pwq after @head. @extra_flags is or'd to
1149 * @extra_flags is or'd to work_struct flags. 1134 * work_struct flags.
1150 * 1135 *
1151 * CONTEXT: 1136 * CONTEXT:
1152 * spin_lock_irq(gcwq->lock). 1137 * spin_lock_irq(pool->lock).
1153 */ 1138 */
1154static void insert_work(struct cpu_workqueue_struct *cwq, 1139static void insert_work(struct pool_workqueue *pwq, struct work_struct *work,
1155 struct work_struct *work, struct list_head *head, 1140 struct list_head *head, unsigned int extra_flags)
1156 unsigned int extra_flags)
1157{ 1141{
1158 struct worker_pool *pool = cwq->pool; 1142 struct worker_pool *pool = pwq->pool;
1159 1143
1160 /* we own @work, set data and link */ 1144 /* we own @work, set data and link */
1161 set_work_cwq(work, cwq, extra_flags); 1145 set_work_pwq(work, pwq, extra_flags);
1162
1163 /*
1164 * Ensure that we get the right work->data if we see the
1165 * result of list_add() below, see try_to_grab_pending().
1166 */
1167 smp_wmb();
1168
1169 list_add_tail(&work->entry, head); 1146 list_add_tail(&work->entry, head);
1170 1147
1171 /* 1148 /*
@@ -1181,41 +1158,24 @@ static void insert_work(struct cpu_workqueue_struct *cwq,
1181 1158
1182/* 1159/*
1183 * Test whether @work is being queued from another work executing on the 1160 * Test whether @work is being queued from another work executing on the
1184 * same workqueue. This is rather expensive and should only be used from 1161 * same workqueue.
1185 * cold paths.
1186 */ 1162 */
1187static bool is_chained_work(struct workqueue_struct *wq) 1163static bool is_chained_work(struct workqueue_struct *wq)
1188{ 1164{
1189 unsigned long flags; 1165 struct worker *worker;
1190 unsigned int cpu;
1191
1192 for_each_gcwq_cpu(cpu) {
1193 struct global_cwq *gcwq = get_gcwq(cpu);
1194 struct worker *worker;
1195 struct hlist_node *pos;
1196 int i;
1197 1166
1198 spin_lock_irqsave(&gcwq->lock, flags); 1167 worker = current_wq_worker();
1199 for_each_busy_worker(worker, i, pos, gcwq) { 1168 /*
1200 if (worker->task != current) 1169 * Return %true iff I'm a worker execuing a work item on @wq. If
1201 continue; 1170 * I'm @worker, it's safe to dereference it without locking.
1202 spin_unlock_irqrestore(&gcwq->lock, flags); 1171 */
1203 /* 1172 return worker && worker->current_pwq->wq == wq;
1204 * I'm @worker, no locking necessary. See if @work
1205 * is headed to the same workqueue.
1206 */
1207 return worker->current_cwq->wq == wq;
1208 }
1209 spin_unlock_irqrestore(&gcwq->lock, flags);
1210 }
1211 return false;
1212} 1173}
1213 1174
1214static void __queue_work(unsigned int cpu, struct workqueue_struct *wq, 1175static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
1215 struct work_struct *work) 1176 struct work_struct *work)
1216{ 1177{
1217 struct global_cwq *gcwq; 1178 struct pool_workqueue *pwq;
1218 struct cpu_workqueue_struct *cwq;
1219 struct list_head *worklist; 1179 struct list_head *worklist;
1220 unsigned int work_flags; 1180 unsigned int work_flags;
1221 unsigned int req_cpu = cpu; 1181 unsigned int req_cpu = cpu;
@@ -1235,9 +1195,9 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
1235 WARN_ON_ONCE(!is_chained_work(wq))) 1195 WARN_ON_ONCE(!is_chained_work(wq)))
1236 return; 1196 return;
1237 1197
1238 /* determine gcwq to use */ 1198 /* determine the pwq to use */
1239 if (!(wq->flags & WQ_UNBOUND)) { 1199 if (!(wq->flags & WQ_UNBOUND)) {
1240 struct global_cwq *last_gcwq; 1200 struct worker_pool *last_pool;
1241 1201
1242 if (cpu == WORK_CPU_UNBOUND) 1202 if (cpu == WORK_CPU_UNBOUND)
1243 cpu = raw_smp_processor_id(); 1203 cpu = raw_smp_processor_id();
@@ -1248,55 +1208,54 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq,
1248 * work needs to be queued on that cpu to guarantee 1208 * work needs to be queued on that cpu to guarantee
1249 * non-reentrancy. 1209 * non-reentrancy.
1250 */ 1210 */
1251 gcwq = get_gcwq(cpu); 1211 pwq = get_pwq(cpu, wq);
1252 last_gcwq = get_work_gcwq(work); 1212 last_pool = get_work_pool(work);
1253 1213
1254 if (last_gcwq && last_gcwq != gcwq) { 1214 if (last_pool && last_pool != pwq->pool) {
1255 struct worker *worker; 1215 struct worker *worker;
1256 1216
1257 spin_lock(&last_gcwq->lock); 1217 spin_lock(&last_pool->lock);
1258 1218
1259 worker = find_worker_executing_work(last_gcwq, work); 1219 worker = find_worker_executing_work(last_pool, work);
1260 1220
1261 if (worker && worker->current_cwq->wq == wq) 1221 if (worker && worker->current_pwq->wq == wq) {
1262 gcwq = last_gcwq; 1222 pwq = get_pwq(last_pool->cpu, wq);
1263 else { 1223 } else {
1264 /* meh... not running there, queue here */ 1224 /* meh... not running there, queue here */
1265 spin_unlock(&last_gcwq->lock); 1225 spin_unlock(&last_pool->lock);
1266 spin_lock(&gcwq->lock); 1226 spin_lock(&pwq->pool->lock);
1267 } 1227 }
1268 } else { 1228 } else {
1269 spin_lock(&gcwq->lock); 1229 spin_lock(&pwq->pool->lock);
1270 } 1230 }
1271 } else { 1231 } else {
1272 gcwq = get_gcwq(WORK_CPU_UNBOUND); 1232 pwq = get_pwq(WORK_CPU_UNBOUND, wq);
1273 spin_lock(&gcwq->lock); 1233 spin_lock(&pwq->pool->lock);
1274 } 1234 }
1275 1235
1276 /* gcwq determined, get cwq and queue */ 1236 /* pwq determined, queue */
1277 cwq = get_cwq(gcwq->cpu, wq); 1237 trace_workqueue_queue_work(req_cpu, pwq, work);
1278 trace_workqueue_queue_work(req_cpu, cwq, work);
1279 1238
1280 if (WARN_ON(!list_empty(&work->entry))) { 1239 if (WARN_ON(!list_empty(&work->entry))) {
1281 spin_unlock(&gcwq->lock); 1240 spin_unlock(&pwq->pool->lock);
1282 return; 1241 return;
1283 } 1242 }
1284 1243
1285 cwq->nr_in_flight[cwq->work_color]++; 1244 pwq->nr_in_flight[pwq->work_color]++;
1286 work_flags = work_color_to_flags(cwq->work_color); 1245 work_flags = work_color_to_flags(pwq->work_color);
1287 1246
1288 if (likely(cwq->nr_active < cwq->max_active)) { 1247 if (likely(pwq->nr_active < pwq->max_active)) {
1289 trace_workqueue_activate_work(work); 1248 trace_workqueue_activate_work(work);
1290 cwq->nr_active++; 1249 pwq->nr_active++;
1291 worklist = &cwq->pool->worklist; 1250 worklist = &pwq->pool->worklist;
1292 } else { 1251 } else {
1293 work_flags |= WORK_STRUCT_DELAYED; 1252 work_flags |= WORK_STRUCT_DELAYED;
1294 worklist = &cwq->delayed_works; 1253 worklist = &pwq->delayed_works;
1295 } 1254 }
1296 1255
1297 insert_work(cwq, work, worklist, work_flags); 1256 insert_work(pwq, work, worklist, work_flags);
1298 1257
1299 spin_unlock(&gcwq->lock); 1258 spin_unlock(&pwq->pool->lock);
1300} 1259}
1301 1260
1302/** 1261/**
@@ -1347,19 +1306,17 @@ EXPORT_SYMBOL_GPL(queue_work);
1347void delayed_work_timer_fn(unsigned long __data) 1306void delayed_work_timer_fn(unsigned long __data)
1348{ 1307{
1349 struct delayed_work *dwork = (struct delayed_work *)__data; 1308 struct delayed_work *dwork = (struct delayed_work *)__data;
1350 struct cpu_workqueue_struct *cwq = get_work_cwq(&dwork->work);
1351 1309
1352 /* should have been called from irqsafe timer with irq already off */ 1310 /* should have been called from irqsafe timer with irq already off */
1353 __queue_work(dwork->cpu, cwq->wq, &dwork->work); 1311 __queue_work(dwork->cpu, dwork->wq, &dwork->work);
1354} 1312}
1355EXPORT_SYMBOL_GPL(delayed_work_timer_fn); 1313EXPORT_SYMBOL(delayed_work_timer_fn);
1356 1314
1357static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, 1315static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
1358 struct delayed_work *dwork, unsigned long delay) 1316 struct delayed_work *dwork, unsigned long delay)
1359{ 1317{
1360 struct timer_list *timer = &dwork->timer; 1318 struct timer_list *timer = &dwork->timer;
1361 struct work_struct *work = &dwork->work; 1319 struct work_struct *work = &dwork->work;
1362 unsigned int lcpu;
1363 1320
1364 WARN_ON_ONCE(timer->function != delayed_work_timer_fn || 1321 WARN_ON_ONCE(timer->function != delayed_work_timer_fn ||
1365 timer->data != (unsigned long)dwork); 1322 timer->data != (unsigned long)dwork);
@@ -1379,30 +1336,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq,
1379 1336
1380 timer_stats_timer_set_start_info(&dwork->timer); 1337 timer_stats_timer_set_start_info(&dwork->timer);
1381 1338
1382 /* 1339 dwork->wq = wq;
1383 * This stores cwq for the moment, for the timer_fn. Note that the
1384 * work's gcwq is preserved to allow reentrance detection for
1385 * delayed works.
1386 */
1387 if (!(wq->flags & WQ_UNBOUND)) {
1388 struct global_cwq *gcwq = get_work_gcwq(work);
1389
1390 /*
1391 * If we cannot get the last gcwq from @work directly,
1392 * select the last CPU such that it avoids unnecessarily
1393 * triggering non-reentrancy check in __queue_work().
1394 */
1395 lcpu = cpu;
1396 if (gcwq)
1397 lcpu = gcwq->cpu;
1398 if (lcpu == WORK_CPU_UNBOUND)
1399 lcpu = raw_smp_processor_id();
1400 } else {
1401 lcpu = WORK_CPU_UNBOUND;
1402 }
1403
1404 set_work_cwq(work, get_cwq(lcpu, wq), 0);
1405
1406 dwork->cpu = cpu; 1340 dwork->cpu = cpu;
1407 timer->expires = jiffies + delay; 1341 timer->expires = jiffies + delay;
1408 1342
@@ -1519,12 +1453,11 @@ EXPORT_SYMBOL_GPL(mod_delayed_work);
1519 * necessary. 1453 * necessary.
1520 * 1454 *
1521 * LOCKING: 1455 * LOCKING:
1522 * spin_lock_irq(gcwq->lock). 1456 * spin_lock_irq(pool->lock).
1523 */ 1457 */
1524static void worker_enter_idle(struct worker *worker) 1458static void worker_enter_idle(struct worker *worker)
1525{ 1459{
1526 struct worker_pool *pool = worker->pool; 1460 struct worker_pool *pool = worker->pool;
1527 struct global_cwq *gcwq = pool->gcwq;
1528 1461
1529 BUG_ON(worker->flags & WORKER_IDLE); 1462 BUG_ON(worker->flags & WORKER_IDLE);
1530 BUG_ON(!list_empty(&worker->entry) && 1463 BUG_ON(!list_empty(&worker->entry) &&
@@ -1542,14 +1475,14 @@ static void worker_enter_idle(struct worker *worker)
1542 mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT); 1475 mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);
1543 1476
1544 /* 1477 /*
1545 * Sanity check nr_running. Because gcwq_unbind_fn() releases 1478 * Sanity check nr_running. Because wq_unbind_fn() releases
1546 * gcwq->lock between setting %WORKER_UNBOUND and zapping 1479 * pool->lock between setting %WORKER_UNBOUND and zapping
1547 * nr_running, the warning may trigger spuriously. Check iff 1480 * nr_running, the warning may trigger spuriously. Check iff
1548 * unbind is not in progress. 1481 * unbind is not in progress.
1549 */ 1482 */
1550 WARN_ON_ONCE(!(gcwq->flags & GCWQ_DISASSOCIATED) && 1483 WARN_ON_ONCE(!(pool->flags & POOL_DISASSOCIATED) &&
1551 pool->nr_workers == pool->nr_idle && 1484 pool->nr_workers == pool->nr_idle &&
1552 atomic_read(get_pool_nr_running(pool))); 1485 atomic_read(&pool->nr_running));
1553} 1486}
1554 1487
1555/** 1488/**
@@ -1559,7 +1492,7 @@ static void worker_enter_idle(struct worker *worker)
1559 * @worker is leaving idle state. Update stats. 1492 * @worker is leaving idle state. Update stats.
1560 * 1493 *
1561 * LOCKING: 1494 * LOCKING:
1562 * spin_lock_irq(gcwq->lock). 1495 * spin_lock_irq(pool->lock).
1563 */ 1496 */
1564static void worker_leave_idle(struct worker *worker) 1497static void worker_leave_idle(struct worker *worker)
1565{ 1498{
@@ -1572,7 +1505,7 @@ static void worker_leave_idle(struct worker *worker)
1572} 1505}
1573 1506
1574/** 1507/**
1575 * worker_maybe_bind_and_lock - bind worker to its cpu if possible and lock gcwq 1508 * worker_maybe_bind_and_lock - bind worker to its cpu if possible and lock pool
1576 * @worker: self 1509 * @worker: self
1577 * 1510 *
1578 * Works which are scheduled while the cpu is online must at least be 1511 * Works which are scheduled while the cpu is online must at least be
@@ -1584,27 +1517,27 @@ static void worker_leave_idle(struct worker *worker)
1584 * themselves to the target cpu and may race with cpu going down or 1517 * themselves to the target cpu and may race with cpu going down or
1585 * coming online. kthread_bind() can't be used because it may put the 1518 * coming online. kthread_bind() can't be used because it may put the
1586 * worker to already dead cpu and set_cpus_allowed_ptr() can't be used 1519 * worker to already dead cpu and set_cpus_allowed_ptr() can't be used
1587 * verbatim as it's best effort and blocking and gcwq may be 1520 * verbatim as it's best effort and blocking and pool may be
1588 * [dis]associated in the meantime. 1521 * [dis]associated in the meantime.
1589 * 1522 *
1590 * This function tries set_cpus_allowed() and locks gcwq and verifies the 1523 * This function tries set_cpus_allowed() and locks pool and verifies the
1591 * binding against %GCWQ_DISASSOCIATED which is set during 1524 * binding against %POOL_DISASSOCIATED which is set during
1592 * %CPU_DOWN_PREPARE and cleared during %CPU_ONLINE, so if the worker 1525 * %CPU_DOWN_PREPARE and cleared during %CPU_ONLINE, so if the worker
1593 * enters idle state or fetches works without dropping lock, it can 1526 * enters idle state or fetches works without dropping lock, it can
1594 * guarantee the scheduling requirement described in the first paragraph. 1527 * guarantee the scheduling requirement described in the first paragraph.
1595 * 1528 *
1596 * CONTEXT: 1529 * CONTEXT:
1597 * Might sleep. Called without any lock but returns with gcwq->lock 1530 * Might sleep. Called without any lock but returns with pool->lock
1598 * held. 1531 * held.
1599 * 1532 *
1600 * RETURNS: 1533 * RETURNS:
1601 * %true if the associated gcwq is online (@worker is successfully 1534 * %true if the associated pool is online (@worker is successfully
1602 * bound), %false if offline. 1535 * bound), %false if offline.
1603 */ 1536 */
1604static bool worker_maybe_bind_and_lock(struct worker *worker) 1537static bool worker_maybe_bind_and_lock(struct worker *worker)
1605__acquires(&gcwq->lock) 1538__acquires(&pool->lock)
1606{ 1539{
1607 struct global_cwq *gcwq = worker->pool->gcwq; 1540 struct worker_pool *pool = worker->pool;
1608 struct task_struct *task = worker->task; 1541 struct task_struct *task = worker->task;
1609 1542
1610 while (true) { 1543 while (true) {
@@ -1612,19 +1545,19 @@ __acquires(&gcwq->lock)
1612 * The following call may fail, succeed or succeed 1545 * The following call may fail, succeed or succeed
1613 * without actually migrating the task to the cpu if 1546 * without actually migrating the task to the cpu if
1614 * it races with cpu hotunplug operation. Verify 1547 * it races with cpu hotunplug operation. Verify
1615 * against GCWQ_DISASSOCIATED. 1548 * against POOL_DISASSOCIATED.
1616 */ 1549 */
1617 if (!(gcwq->flags & GCWQ_DISASSOCIATED)) 1550 if (!(pool->flags & POOL_DISASSOCIATED))
1618 set_cpus_allowed_ptr(task, get_cpu_mask(gcwq->cpu)); 1551 set_cpus_allowed_ptr(task, get_cpu_mask(pool->cpu));
1619 1552
1620 spin_lock_irq(&gcwq->lock); 1553 spin_lock_irq(&pool->lock);
1621 if (gcwq->flags & GCWQ_DISASSOCIATED) 1554 if (pool->flags & POOL_DISASSOCIATED)
1622 return false; 1555 return false;
1623 if (task_cpu(task) == gcwq->cpu && 1556 if (task_cpu(task) == pool->cpu &&
1624 cpumask_equal(&current->cpus_allowed, 1557 cpumask_equal(&current->cpus_allowed,
1625 get_cpu_mask(gcwq->cpu))) 1558 get_cpu_mask(pool->cpu)))
1626 return true; 1559 return true;
1627 spin_unlock_irq(&gcwq->lock); 1560 spin_unlock_irq(&pool->lock);
1628 1561
1629 /* 1562 /*
1630 * We've raced with CPU hot[un]plug. Give it a breather 1563 * We've raced with CPU hot[un]plug. Give it a breather
@@ -1643,15 +1576,13 @@ __acquires(&gcwq->lock)
1643 */ 1576 */
1644static void idle_worker_rebind(struct worker *worker) 1577static void idle_worker_rebind(struct worker *worker)
1645{ 1578{
1646 struct global_cwq *gcwq = worker->pool->gcwq;
1647
1648 /* CPU may go down again inbetween, clear UNBOUND only on success */ 1579 /* CPU may go down again inbetween, clear UNBOUND only on success */
1649 if (worker_maybe_bind_and_lock(worker)) 1580 if (worker_maybe_bind_and_lock(worker))
1650 worker_clr_flags(worker, WORKER_UNBOUND); 1581 worker_clr_flags(worker, WORKER_UNBOUND);
1651 1582
1652 /* rebind complete, become available again */ 1583 /* rebind complete, become available again */
1653 list_add(&worker->entry, &worker->pool->idle_list); 1584 list_add(&worker->entry, &worker->pool->idle_list);
1654 spin_unlock_irq(&gcwq->lock); 1585 spin_unlock_irq(&worker->pool->lock);
1655} 1586}
1656 1587
1657/* 1588/*
@@ -1663,19 +1594,18 @@ static void idle_worker_rebind(struct worker *worker)
1663static void busy_worker_rebind_fn(struct work_struct *work) 1594static void busy_worker_rebind_fn(struct work_struct *work)
1664{ 1595{
1665 struct worker *worker = container_of(work, struct worker, rebind_work); 1596 struct worker *worker = container_of(work, struct worker, rebind_work);
1666 struct global_cwq *gcwq = worker->pool->gcwq;
1667 1597
1668 if (worker_maybe_bind_and_lock(worker)) 1598 if (worker_maybe_bind_and_lock(worker))
1669 worker_clr_flags(worker, WORKER_UNBOUND); 1599 worker_clr_flags(worker, WORKER_UNBOUND);
1670 1600
1671 spin_unlock_irq(&gcwq->lock); 1601 spin_unlock_irq(&worker->pool->lock);
1672} 1602}
1673 1603
1674/** 1604/**
1675 * rebind_workers - rebind all workers of a gcwq to the associated CPU 1605 * rebind_workers - rebind all workers of a pool to the associated CPU
1676 * @gcwq: gcwq of interest 1606 * @pool: pool of interest
1677 * 1607 *
1678 * @gcwq->cpu is coming online. Rebind all workers to the CPU. Rebinding 1608 * @pool->cpu is coming online. Rebind all workers to the CPU. Rebinding
1679 * is different for idle and busy ones. 1609 * is different for idle and busy ones.
1680 * 1610 *
1681 * Idle ones will be removed from the idle_list and woken up. They will 1611 * Idle ones will be removed from the idle_list and woken up. They will
@@ -1693,38 +1623,32 @@ static void busy_worker_rebind_fn(struct work_struct *work)
1693 * including the manager will not appear on @idle_list until rebind is 1623 * including the manager will not appear on @idle_list until rebind is
1694 * complete, making local wake-ups safe. 1624 * complete, making local wake-ups safe.
1695 */ 1625 */
1696static void rebind_workers(struct global_cwq *gcwq) 1626static void rebind_workers(struct worker_pool *pool)
1697{ 1627{
1698 struct worker_pool *pool;
1699 struct worker *worker, *n; 1628 struct worker *worker, *n;
1700 struct hlist_node *pos; 1629 struct hlist_node *pos;
1701 int i; 1630 int i;
1702 1631
1703 lockdep_assert_held(&gcwq->lock); 1632 lockdep_assert_held(&pool->assoc_mutex);
1704 1633 lockdep_assert_held(&pool->lock);
1705 for_each_worker_pool(pool, gcwq)
1706 lockdep_assert_held(&pool->assoc_mutex);
1707 1634
1708 /* dequeue and kick idle ones */ 1635 /* dequeue and kick idle ones */
1709 for_each_worker_pool(pool, gcwq) { 1636 list_for_each_entry_safe(worker, n, &pool->idle_list, entry) {
1710 list_for_each_entry_safe(worker, n, &pool->idle_list, entry) { 1637 /*
1711 /* 1638 * idle workers should be off @pool->idle_list until rebind
1712 * idle workers should be off @pool->idle_list 1639 * is complete to avoid receiving premature local wake-ups.
1713 * until rebind is complete to avoid receiving 1640 */
1714 * premature local wake-ups. 1641 list_del_init(&worker->entry);
1715 */
1716 list_del_init(&worker->entry);
1717 1642
1718 /* 1643 /*
1719 * worker_thread() will see the above dequeuing 1644 * worker_thread() will see the above dequeuing and call
1720 * and call idle_worker_rebind(). 1645 * idle_worker_rebind().
1721 */ 1646 */
1722 wake_up_process(worker->task); 1647 wake_up_process(worker->task);
1723 }
1724 } 1648 }
1725 1649
1726 /* rebind busy workers */ 1650 /* rebind busy workers */
1727 for_each_busy_worker(worker, i, pos, gcwq) { 1651 for_each_busy_worker(worker, i, pos, pool) {
1728 struct work_struct *rebind_work = &worker->rebind_work; 1652 struct work_struct *rebind_work = &worker->rebind_work;
1729 struct workqueue_struct *wq; 1653 struct workqueue_struct *wq;
1730 1654
@@ -1736,16 +1660,16 @@ static void rebind_workers(struct global_cwq *gcwq)
1736 1660
1737 /* 1661 /*
1738 * wq doesn't really matter but let's keep @worker->pool 1662 * wq doesn't really matter but let's keep @worker->pool
1739 * and @cwq->pool consistent for sanity. 1663 * and @pwq->pool consistent for sanity.
1740 */ 1664 */
1741 if (worker_pool_pri(worker->pool)) 1665 if (std_worker_pool_pri(worker->pool))
1742 wq = system_highpri_wq; 1666 wq = system_highpri_wq;
1743 else 1667 else
1744 wq = system_wq; 1668 wq = system_wq;
1745 1669
1746 insert_work(get_cwq(gcwq->cpu, wq), rebind_work, 1670 insert_work(get_pwq(pool->cpu, wq), rebind_work,
1747 worker->scheduled.next, 1671 worker->scheduled.next,
1748 work_color_to_flags(WORK_NO_COLOR)); 1672 work_color_to_flags(WORK_NO_COLOR));
1749 } 1673 }
1750} 1674}
1751 1675
@@ -1780,19 +1704,18 @@ static struct worker *alloc_worker(void)
1780 */ 1704 */
1781static struct worker *create_worker(struct worker_pool *pool) 1705static struct worker *create_worker(struct worker_pool *pool)
1782{ 1706{
1783 struct global_cwq *gcwq = pool->gcwq; 1707 const char *pri = std_worker_pool_pri(pool) ? "H" : "";
1784 const char *pri = worker_pool_pri(pool) ? "H" : "";
1785 struct worker *worker = NULL; 1708 struct worker *worker = NULL;
1786 int id = -1; 1709 int id = -1;
1787 1710
1788 spin_lock_irq(&gcwq->lock); 1711 spin_lock_irq(&pool->lock);
1789 while (ida_get_new(&pool->worker_ida, &id)) { 1712 while (ida_get_new(&pool->worker_ida, &id)) {
1790 spin_unlock_irq(&gcwq->lock); 1713 spin_unlock_irq(&pool->lock);
1791 if (!ida_pre_get(&pool->worker_ida, GFP_KERNEL)) 1714 if (!ida_pre_get(&pool->worker_ida, GFP_KERNEL))
1792 goto fail; 1715 goto fail;
1793 spin_lock_irq(&gcwq->lock); 1716 spin_lock_irq(&pool->lock);
1794 } 1717 }
1795 spin_unlock_irq(&gcwq->lock); 1718 spin_unlock_irq(&pool->lock);
1796 1719
1797 worker = alloc_worker(); 1720 worker = alloc_worker();
1798 if (!worker) 1721 if (!worker)
@@ -1801,30 +1724,30 @@ static struct worker *create_worker(struct worker_pool *pool)
1801 worker->pool = pool; 1724 worker->pool = pool;
1802 worker->id = id; 1725 worker->id = id;
1803 1726
1804 if (gcwq->cpu != WORK_CPU_UNBOUND) 1727 if (pool->cpu != WORK_CPU_UNBOUND)
1805 worker->task = kthread_create_on_node(worker_thread, 1728 worker->task = kthread_create_on_node(worker_thread,
1806 worker, cpu_to_node(gcwq->cpu), 1729 worker, cpu_to_node(pool->cpu),
1807 "kworker/%u:%d%s", gcwq->cpu, id, pri); 1730 "kworker/%u:%d%s", pool->cpu, id, pri);
1808 else 1731 else
1809 worker->task = kthread_create(worker_thread, worker, 1732 worker->task = kthread_create(worker_thread, worker,
1810 "kworker/u:%d%s", id, pri); 1733 "kworker/u:%d%s", id, pri);
1811 if (IS_ERR(worker->task)) 1734 if (IS_ERR(worker->task))
1812 goto fail; 1735 goto fail;
1813 1736
1814 if (worker_pool_pri(pool)) 1737 if (std_worker_pool_pri(pool))
1815 set_user_nice(worker->task, HIGHPRI_NICE_LEVEL); 1738 set_user_nice(worker->task, HIGHPRI_NICE_LEVEL);
1816 1739
1817 /* 1740 /*
1818 * Determine CPU binding of the new worker depending on 1741 * Determine CPU binding of the new worker depending on
1819 * %GCWQ_DISASSOCIATED. The caller is responsible for ensuring the 1742 * %POOL_DISASSOCIATED. The caller is responsible for ensuring the
1820 * flag remains stable across this function. See the comments 1743 * flag remains stable across this function. See the comments
1821 * above the flag definition for details. 1744 * above the flag definition for details.
1822 * 1745 *
1823 * As an unbound worker may later become a regular one if CPU comes 1746 * As an unbound worker may later become a regular one if CPU comes
1824 * online, make sure every worker has %PF_THREAD_BOUND set. 1747 * online, make sure every worker has %PF_THREAD_BOUND set.
1825 */ 1748 */
1826 if (!(gcwq->flags & GCWQ_DISASSOCIATED)) { 1749 if (!(pool->flags & POOL_DISASSOCIATED)) {
1827 kthread_bind(worker->task, gcwq->cpu); 1750 kthread_bind(worker->task, pool->cpu);
1828 } else { 1751 } else {
1829 worker->task->flags |= PF_THREAD_BOUND; 1752 worker->task->flags |= PF_THREAD_BOUND;
1830 worker->flags |= WORKER_UNBOUND; 1753 worker->flags |= WORKER_UNBOUND;
@@ -1833,9 +1756,9 @@ static struct worker *create_worker(struct worker_pool *pool)
1833 return worker; 1756 return worker;
1834fail: 1757fail:
1835 if (id >= 0) { 1758 if (id >= 0) {
1836 spin_lock_irq(&gcwq->lock); 1759 spin_lock_irq(&pool->lock);
1837 ida_remove(&pool->worker_ida, id); 1760 ida_remove(&pool->worker_ida, id);
1838 spin_unlock_irq(&gcwq->lock); 1761 spin_unlock_irq(&pool->lock);
1839 } 1762 }
1840 kfree(worker); 1763 kfree(worker);
1841 return NULL; 1764 return NULL;
@@ -1845,10 +1768,10 @@ fail:
1845 * start_worker - start a newly created worker 1768 * start_worker - start a newly created worker
1846 * @worker: worker to start 1769 * @worker: worker to start
1847 * 1770 *
1848 * Make the gcwq aware of @worker and start it. 1771 * Make the pool aware of @worker and start it.
1849 * 1772 *
1850 * CONTEXT: 1773 * CONTEXT:
1851 * spin_lock_irq(gcwq->lock). 1774 * spin_lock_irq(pool->lock).
1852 */ 1775 */
1853static void start_worker(struct worker *worker) 1776static void start_worker(struct worker *worker)
1854{ 1777{
@@ -1862,15 +1785,14 @@ static void start_worker(struct worker *worker)
1862 * destroy_worker - destroy a workqueue worker 1785 * destroy_worker - destroy a workqueue worker
1863 * @worker: worker to be destroyed 1786 * @worker: worker to be destroyed
1864 * 1787 *
1865 * Destroy @worker and adjust @gcwq stats accordingly. 1788 * Destroy @worker and adjust @pool stats accordingly.
1866 * 1789 *
1867 * CONTEXT: 1790 * CONTEXT:
1868 * spin_lock_irq(gcwq->lock) which is released and regrabbed. 1791 * spin_lock_irq(pool->lock) which is released and regrabbed.
1869 */ 1792 */
1870static void destroy_worker(struct worker *worker) 1793static void destroy_worker(struct worker *worker)
1871{ 1794{
1872 struct worker_pool *pool = worker->pool; 1795 struct worker_pool *pool = worker->pool;
1873 struct global_cwq *gcwq = pool->gcwq;
1874 int id = worker->id; 1796 int id = worker->id;
1875 1797
1876 /* sanity check frenzy */ 1798 /* sanity check frenzy */
@@ -1885,21 +1807,20 @@ static void destroy_worker(struct worker *worker)
1885 list_del_init(&worker->entry); 1807 list_del_init(&worker->entry);
1886 worker->flags |= WORKER_DIE; 1808 worker->flags |= WORKER_DIE;
1887 1809
1888 spin_unlock_irq(&gcwq->lock); 1810 spin_unlock_irq(&pool->lock);
1889 1811
1890 kthread_stop(worker->task); 1812 kthread_stop(worker->task);
1891 kfree(worker); 1813 kfree(worker);
1892 1814
1893 spin_lock_irq(&gcwq->lock); 1815 spin_lock_irq(&pool->lock);
1894 ida_remove(&pool->worker_ida, id); 1816 ida_remove(&pool->worker_ida, id);
1895} 1817}
1896 1818
1897static void idle_worker_timeout(unsigned long __pool) 1819static void idle_worker_timeout(unsigned long __pool)
1898{ 1820{
1899 struct worker_pool *pool = (void *)__pool; 1821 struct worker_pool *pool = (void *)__pool;
1900 struct global_cwq *gcwq = pool->gcwq;
1901 1822
1902 spin_lock_irq(&gcwq->lock); 1823 spin_lock_irq(&pool->lock);
1903 1824
1904 if (too_many_workers(pool)) { 1825 if (too_many_workers(pool)) {
1905 struct worker *worker; 1826 struct worker *worker;
@@ -1918,20 +1839,20 @@ static void idle_worker_timeout(unsigned long __pool)
1918 } 1839 }
1919 } 1840 }
1920 1841
1921 spin_unlock_irq(&gcwq->lock); 1842 spin_unlock_irq(&pool->lock);
1922} 1843}
1923 1844
1924static bool send_mayday(struct work_struct *work) 1845static bool send_mayday(struct work_struct *work)
1925{ 1846{
1926 struct cpu_workqueue_struct *cwq = get_work_cwq(work); 1847 struct pool_workqueue *pwq = get_work_pwq(work);
1927 struct workqueue_struct *wq = cwq->wq; 1848 struct workqueue_struct *wq = pwq->wq;
1928 unsigned int cpu; 1849 unsigned int cpu;
1929 1850
1930 if (!(wq->flags & WQ_RESCUER)) 1851 if (!(wq->flags & WQ_RESCUER))
1931 return false; 1852 return false;
1932 1853
1933 /* mayday mayday mayday */ 1854 /* mayday mayday mayday */
1934 cpu = cwq->pool->gcwq->cpu; 1855 cpu = pwq->pool->cpu;
1935 /* WORK_CPU_UNBOUND can't be set in cpumask, use cpu 0 instead */ 1856 /* WORK_CPU_UNBOUND can't be set in cpumask, use cpu 0 instead */
1936 if (cpu == WORK_CPU_UNBOUND) 1857 if (cpu == WORK_CPU_UNBOUND)
1937 cpu = 0; 1858 cpu = 0;
@@ -1940,13 +1861,12 @@ static bool send_mayday(struct work_struct *work)
1940 return true; 1861 return true;
1941} 1862}
1942 1863
1943static void gcwq_mayday_timeout(unsigned long __pool) 1864static void pool_mayday_timeout(unsigned long __pool)
1944{ 1865{
1945 struct worker_pool *pool = (void *)__pool; 1866 struct worker_pool *pool = (void *)__pool;
1946 struct global_cwq *gcwq = pool->gcwq;
1947 struct work_struct *work; 1867 struct work_struct *work;
1948 1868
1949 spin_lock_irq(&gcwq->lock); 1869 spin_lock_irq(&pool->lock);
1950 1870
1951 if (need_to_create_worker(pool)) { 1871 if (need_to_create_worker(pool)) {
1952 /* 1872 /*
@@ -1959,7 +1879,7 @@ static void gcwq_mayday_timeout(unsigned long __pool)
1959 send_mayday(work); 1879 send_mayday(work);
1960 } 1880 }
1961 1881
1962 spin_unlock_irq(&gcwq->lock); 1882 spin_unlock_irq(&pool->lock);
1963 1883
1964 mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INTERVAL); 1884 mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INTERVAL);
1965} 1885}
@@ -1978,24 +1898,22 @@ static void gcwq_mayday_timeout(unsigned long __pool)
1978 * may_start_working() true. 1898 * may_start_working() true.
1979 * 1899 *
1980 * LOCKING: 1900 * LOCKING:
1981 * spin_lock_irq(gcwq->lock) which may be released and regrabbed 1901 * spin_lock_irq(pool->lock) which may be released and regrabbed
1982 * multiple times. Does GFP_KERNEL allocations. Called only from 1902 * multiple times. Does GFP_KERNEL allocations. Called only from
1983 * manager. 1903 * manager.
1984 * 1904 *
1985 * RETURNS: 1905 * RETURNS:
1986 * false if no action was taken and gcwq->lock stayed locked, true 1906 * false if no action was taken and pool->lock stayed locked, true
1987 * otherwise. 1907 * otherwise.
1988 */ 1908 */
1989static bool maybe_create_worker(struct worker_pool *pool) 1909static bool maybe_create_worker(struct worker_pool *pool)
1990__releases(&gcwq->lock) 1910__releases(&pool->lock)
1991__acquires(&gcwq->lock) 1911__acquires(&pool->lock)
1992{ 1912{
1993 struct global_cwq *gcwq = pool->gcwq;
1994
1995 if (!need_to_create_worker(pool)) 1913 if (!need_to_create_worker(pool))
1996 return false; 1914 return false;
1997restart: 1915restart:
1998 spin_unlock_irq(&gcwq->lock); 1916 spin_unlock_irq(&pool->lock);
1999 1917
2000 /* if we don't make progress in MAYDAY_INITIAL_TIMEOUT, call for help */ 1918 /* if we don't make progress in MAYDAY_INITIAL_TIMEOUT, call for help */
2001 mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INITIAL_TIMEOUT); 1919 mod_timer(&pool->mayday_timer, jiffies + MAYDAY_INITIAL_TIMEOUT);
@@ -2006,7 +1924,7 @@ restart:
2006 worker = create_worker(pool); 1924 worker = create_worker(pool);
2007 if (worker) { 1925 if (worker) {
2008 del_timer_sync(&pool->mayday_timer); 1926 del_timer_sync(&pool->mayday_timer);
2009 spin_lock_irq(&gcwq->lock); 1927 spin_lock_irq(&pool->lock);
2010 start_worker(worker); 1928 start_worker(worker);
2011 BUG_ON(need_to_create_worker(pool)); 1929 BUG_ON(need_to_create_worker(pool));
2012 return true; 1930 return true;
@@ -2023,7 +1941,7 @@ restart:
2023 } 1941 }
2024 1942
2025 del_timer_sync(&pool->mayday_timer); 1943 del_timer_sync(&pool->mayday_timer);
2026 spin_lock_irq(&gcwq->lock); 1944 spin_lock_irq(&pool->lock);
2027 if (need_to_create_worker(pool)) 1945 if (need_to_create_worker(pool))
2028 goto restart; 1946 goto restart;
2029 return true; 1947 return true;
@@ -2037,11 +1955,11 @@ restart:
2037 * IDLE_WORKER_TIMEOUT. 1955 * IDLE_WORKER_TIMEOUT.
2038 * 1956 *
2039 * LOCKING: 1957 * LOCKING:
2040 * spin_lock_irq(gcwq->lock) which may be released and regrabbed 1958 * spin_lock_irq(pool->lock) which may be released and regrabbed
2041 * multiple times. Called only from manager. 1959 * multiple times. Called only from manager.
2042 * 1960 *
2043 * RETURNS: 1961 * RETURNS:
2044 * false if no action was taken and gcwq->lock stayed locked, true 1962 * false if no action was taken and pool->lock stayed locked, true
2045 * otherwise. 1963 * otherwise.
2046 */ 1964 */
2047static bool maybe_destroy_workers(struct worker_pool *pool) 1965static bool maybe_destroy_workers(struct worker_pool *pool)
@@ -2071,21 +1989,21 @@ static bool maybe_destroy_workers(struct worker_pool *pool)
2071 * manage_workers - manage worker pool 1989 * manage_workers - manage worker pool
2072 * @worker: self 1990 * @worker: self
2073 * 1991 *
2074 * Assume the manager role and manage gcwq worker pool @worker belongs 1992 * Assume the manager role and manage the worker pool @worker belongs
2075 * to. At any given time, there can be only zero or one manager per 1993 * to. At any given time, there can be only zero or one manager per
2076 * gcwq. The exclusion is handled automatically by this function. 1994 * pool. The exclusion is handled automatically by this function.
2077 * 1995 *
2078 * The caller can safely start processing works on false return. On 1996 * The caller can safely start processing works on false return. On
2079 * true return, it's guaranteed that need_to_create_worker() is false 1997 * true return, it's guaranteed that need_to_create_worker() is false
2080 * and may_start_working() is true. 1998 * and may_start_working() is true.
2081 * 1999 *
2082 * CONTEXT: 2000 * CONTEXT:
2083 * spin_lock_irq(gcwq->lock) which may be released and regrabbed 2001 * spin_lock_irq(pool->lock) which may be released and regrabbed
2084 * multiple times. Does GFP_KERNEL allocations. 2002 * multiple times. Does GFP_KERNEL allocations.
2085 * 2003 *
2086 * RETURNS: 2004 * RETURNS:
2087 * false if no action was taken and gcwq->lock stayed locked, true if 2005 * spin_lock_irq(pool->lock) which may be released and regrabbed
2088 * some action was taken. 2006 * multiple times. Does GFP_KERNEL allocations.
2089 */ 2007 */
2090static bool manage_workers(struct worker *worker) 2008static bool manage_workers(struct worker *worker)
2091{ 2009{
@@ -2107,20 +2025,20 @@ static bool manage_workers(struct worker *worker)
2107 * manager against CPU hotplug. 2025 * manager against CPU hotplug.
2108 * 2026 *
2109 * assoc_mutex would always be free unless CPU hotplug is in 2027 * assoc_mutex would always be free unless CPU hotplug is in
2110 * progress. trylock first without dropping @gcwq->lock. 2028 * progress. trylock first without dropping @pool->lock.
2111 */ 2029 */
2112 if (unlikely(!mutex_trylock(&pool->assoc_mutex))) { 2030 if (unlikely(!mutex_trylock(&pool->assoc_mutex))) {
2113 spin_unlock_irq(&pool->gcwq->lock); 2031 spin_unlock_irq(&pool->lock);
2114 mutex_lock(&pool->assoc_mutex); 2032 mutex_lock(&pool->assoc_mutex);
2115 /* 2033 /*
2116 * CPU hotplug could have happened while we were waiting 2034 * CPU hotplug could have happened while we were waiting
2117 * for assoc_mutex. Hotplug itself can't handle us 2035 * for assoc_mutex. Hotplug itself can't handle us
2118 * because manager isn't either on idle or busy list, and 2036 * because manager isn't either on idle or busy list, and
2119 * @gcwq's state and ours could have deviated. 2037 * @pool's state and ours could have deviated.
2120 * 2038 *
2121 * As hotplug is now excluded via assoc_mutex, we can 2039 * As hotplug is now excluded via assoc_mutex, we can
2122 * simply try to bind. It will succeed or fail depending 2040 * simply try to bind. It will succeed or fail depending
2123 * on @gcwq's current state. Try it and adjust 2041 * on @pool's current state. Try it and adjust
2124 * %WORKER_UNBOUND accordingly. 2042 * %WORKER_UNBOUND accordingly.
2125 */ 2043 */
2126 if (worker_maybe_bind_and_lock(worker)) 2044 if (worker_maybe_bind_and_lock(worker))
@@ -2157,18 +2075,15 @@ static bool manage_workers(struct worker *worker)
2157 * call this function to process a work. 2075 * call this function to process a work.
2158 * 2076 *
2159 * CONTEXT: 2077 * CONTEXT:
2160 * spin_lock_irq(gcwq->lock) which is released and regrabbed. 2078 * spin_lock_irq(pool->lock) which is released and regrabbed.
2161 */ 2079 */
2162static void process_one_work(struct worker *worker, struct work_struct *work) 2080static void process_one_work(struct worker *worker, struct work_struct *work)
2163__releases(&gcwq->lock) 2081__releases(&pool->lock)
2164__acquires(&gcwq->lock) 2082__acquires(&pool->lock)
2165{ 2083{
2166 struct cpu_workqueue_struct *cwq = get_work_cwq(work); 2084 struct pool_workqueue *pwq = get_work_pwq(work);
2167 struct worker_pool *pool = worker->pool; 2085 struct worker_pool *pool = worker->pool;
2168 struct global_cwq *gcwq = pool->gcwq; 2086 bool cpu_intensive = pwq->wq->flags & WQ_CPU_INTENSIVE;
2169 struct hlist_head *bwh = busy_worker_head(gcwq, work);
2170 bool cpu_intensive = cwq->wq->flags & WQ_CPU_INTENSIVE;
2171 work_func_t f = work->func;
2172 int work_color; 2087 int work_color;
2173 struct worker *collision; 2088 struct worker *collision;
2174#ifdef CONFIG_LOCKDEP 2089#ifdef CONFIG_LOCKDEP
@@ -2186,11 +2101,11 @@ __acquires(&gcwq->lock)
2186 /* 2101 /*
2187 * Ensure we're on the correct CPU. DISASSOCIATED test is 2102 * Ensure we're on the correct CPU. DISASSOCIATED test is
2188 * necessary to avoid spurious warnings from rescuers servicing the 2103 * necessary to avoid spurious warnings from rescuers servicing the
2189 * unbound or a disassociated gcwq. 2104 * unbound or a disassociated pool.
2190 */ 2105 */
2191 WARN_ON_ONCE(!(worker->flags & WORKER_UNBOUND) && 2106 WARN_ON_ONCE(!(worker->flags & WORKER_UNBOUND) &&
2192 !(gcwq->flags & GCWQ_DISASSOCIATED) && 2107 !(pool->flags & POOL_DISASSOCIATED) &&
2193 raw_smp_processor_id() != gcwq->cpu); 2108 raw_smp_processor_id() != pool->cpu);
2194 2109
2195 /* 2110 /*
2196 * A single work shouldn't be executed concurrently by 2111 * A single work shouldn't be executed concurrently by
@@ -2198,7 +2113,7 @@ __acquires(&gcwq->lock)
2198 * already processing the work. If so, defer the work to the 2113 * already processing the work. If so, defer the work to the
2199 * currently executing one. 2114 * currently executing one.
2200 */ 2115 */
2201 collision = __find_worker_executing_work(gcwq, bwh, work); 2116 collision = find_worker_executing_work(pool, work);
2202 if (unlikely(collision)) { 2117 if (unlikely(collision)) {
2203 move_linked_works(work, &collision->scheduled, NULL); 2118 move_linked_works(work, &collision->scheduled, NULL);
2204 return; 2119 return;
@@ -2206,9 +2121,10 @@ __acquires(&gcwq->lock)
2206 2121
2207 /* claim and dequeue */ 2122 /* claim and dequeue */
2208 debug_work_deactivate(work); 2123 debug_work_deactivate(work);
2209 hlist_add_head(&worker->hentry, bwh); 2124 hash_add(pool->busy_hash, &worker->hentry, (unsigned long)work);
2210 worker->current_work = work; 2125 worker->current_work = work;
2211 worker->current_cwq = cwq; 2126 worker->current_func = work->func;
2127 worker->current_pwq = pwq;
2212 work_color = get_work_color(work); 2128 work_color = get_work_color(work);
2213 2129
2214 list_del_init(&work->entry); 2130 list_del_init(&work->entry);
@@ -2221,53 +2137,55 @@ __acquires(&gcwq->lock)
2221 worker_set_flags(worker, WORKER_CPU_INTENSIVE, true); 2137 worker_set_flags(worker, WORKER_CPU_INTENSIVE, true);
2222 2138
2223 /* 2139 /*
2224 * Unbound gcwq isn't concurrency managed and work items should be 2140 * Unbound pool isn't concurrency managed and work items should be
2225 * executed ASAP. Wake up another worker if necessary. 2141 * executed ASAP. Wake up another worker if necessary.
2226 */ 2142 */
2227 if ((worker->flags & WORKER_UNBOUND) && need_more_worker(pool)) 2143 if ((worker->flags & WORKER_UNBOUND) && need_more_worker(pool))
2228 wake_up_worker(pool); 2144 wake_up_worker(pool);
2229 2145
2230 /* 2146 /*
2231 * Record the last CPU and clear PENDING which should be the last 2147 * Record the last pool and clear PENDING which should be the last
2232 * update to @work. Also, do this inside @gcwq->lock so that 2148 * update to @work. Also, do this inside @pool->lock so that
2233 * PENDING and queued state changes happen together while IRQ is 2149 * PENDING and queued state changes happen together while IRQ is
2234 * disabled. 2150 * disabled.
2235 */ 2151 */
2236 set_work_cpu_and_clear_pending(work, gcwq->cpu); 2152 set_work_pool_and_clear_pending(work, pool->id);
2237 2153
2238 spin_unlock_irq(&gcwq->lock); 2154 spin_unlock_irq(&pool->lock);
2239 2155
2240 lock_map_acquire_read(&cwq->wq->lockdep_map); 2156 lock_map_acquire_read(&pwq->wq->lockdep_map);
2241 lock_map_acquire(&lockdep_map); 2157 lock_map_acquire(&lockdep_map);
2242 trace_workqueue_execute_start(work); 2158 trace_workqueue_execute_start(work);
2243 f(work); 2159 worker->current_func(work);
2244 /* 2160 /*
2245 * While we must be careful to not use "work" after this, the trace 2161 * While we must be careful to not use "work" after this, the trace
2246 * point will only record its address. 2162 * point will only record its address.
2247 */ 2163 */
2248 trace_workqueue_execute_end(work); 2164 trace_workqueue_execute_end(work);
2249 lock_map_release(&lockdep_map); 2165 lock_map_release(&lockdep_map);
2250 lock_map_release(&cwq->wq->lockdep_map); 2166 lock_map_release(&pwq->wq->lockdep_map);
2251 2167
2252 if (unlikely(in_atomic() || lockdep_depth(current) > 0)) { 2168 if (unlikely(in_atomic() || lockdep_depth(current) > 0)) {
2253 pr_err("BUG: workqueue leaked lock or atomic: %s/0x%08x/%d\n" 2169 pr_err("BUG: workqueue leaked lock or atomic: %s/0x%08x/%d\n"
2254 " last function: %pf\n", 2170 " last function: %pf\n",
2255 current->comm, preempt_count(), task_pid_nr(current), f); 2171 current->comm, preempt_count(), task_pid_nr(current),
2172 worker->current_func);
2256 debug_show_held_locks(current); 2173 debug_show_held_locks(current);
2257 dump_stack(); 2174 dump_stack();
2258 } 2175 }
2259 2176
2260 spin_lock_irq(&gcwq->lock); 2177 spin_lock_irq(&pool->lock);
2261 2178
2262 /* clear cpu intensive status */ 2179 /* clear cpu intensive status */
2263 if (unlikely(cpu_intensive)) 2180 if (unlikely(cpu_intensive))
2264 worker_clr_flags(worker, WORKER_CPU_INTENSIVE); 2181 worker_clr_flags(worker, WORKER_CPU_INTENSIVE);
2265 2182
2266 /* we're done with it, release */ 2183 /* we're done with it, release */
2267 hlist_del_init(&worker->hentry); 2184 hash_del(&worker->hentry);
2268 worker->current_work = NULL; 2185 worker->current_work = NULL;
2269 worker->current_cwq = NULL; 2186 worker->current_func = NULL;
2270 cwq_dec_nr_in_flight(cwq, work_color); 2187 worker->current_pwq = NULL;
2188 pwq_dec_nr_in_flight(pwq, work_color);
2271} 2189}
2272 2190
2273/** 2191/**
@@ -2279,7 +2197,7 @@ __acquires(&gcwq->lock)
2279 * fetches a work from the top and executes it. 2197 * fetches a work from the top and executes it.
2280 * 2198 *
2281 * CONTEXT: 2199 * CONTEXT:
2282 * spin_lock_irq(gcwq->lock) which may be released and regrabbed 2200 * spin_lock_irq(pool->lock) which may be released and regrabbed
2283 * multiple times. 2201 * multiple times.
2284 */ 2202 */
2285static void process_scheduled_works(struct worker *worker) 2203static void process_scheduled_works(struct worker *worker)
@@ -2295,8 +2213,8 @@ static void process_scheduled_works(struct worker *worker)
2295 * worker_thread - the worker thread function 2213 * worker_thread - the worker thread function
2296 * @__worker: self 2214 * @__worker: self
2297 * 2215 *
2298 * The gcwq worker thread function. There's a single dynamic pool of 2216 * The worker thread function. There are NR_CPU_WORKER_POOLS dynamic pools
2299 * these per each cpu. These workers process all works regardless of 2217 * of these per each cpu. These workers process all works regardless of
2300 * their specific target workqueue. The only exception is works which 2218 * their specific target workqueue. The only exception is works which
2301 * belong to workqueues with a rescuer which will be explained in 2219 * belong to workqueues with a rescuer which will be explained in
2302 * rescuer_thread(). 2220 * rescuer_thread().
@@ -2305,16 +2223,15 @@ static int worker_thread(void *__worker)
2305{ 2223{
2306 struct worker *worker = __worker; 2224 struct worker *worker = __worker;
2307 struct worker_pool *pool = worker->pool; 2225 struct worker_pool *pool = worker->pool;
2308 struct global_cwq *gcwq = pool->gcwq;
2309 2226
2310 /* tell the scheduler that this is a workqueue worker */ 2227 /* tell the scheduler that this is a workqueue worker */
2311 worker->task->flags |= PF_WQ_WORKER; 2228 worker->task->flags |= PF_WQ_WORKER;
2312woke_up: 2229woke_up:
2313 spin_lock_irq(&gcwq->lock); 2230 spin_lock_irq(&pool->lock);
2314 2231
2315 /* we are off idle list if destruction or rebind is requested */ 2232 /* we are off idle list if destruction or rebind is requested */
2316 if (unlikely(list_empty(&worker->entry))) { 2233 if (unlikely(list_empty(&worker->entry))) {
2317 spin_unlock_irq(&gcwq->lock); 2234 spin_unlock_irq(&pool->lock);
2318 2235
2319 /* if DIE is set, destruction is requested */ 2236 /* if DIE is set, destruction is requested */
2320 if (worker->flags & WORKER_DIE) { 2237 if (worker->flags & WORKER_DIE) {
@@ -2373,52 +2290,59 @@ sleep:
2373 goto recheck; 2290 goto recheck;
2374 2291
2375 /* 2292 /*
2376 * gcwq->lock is held and there's no work to process and no 2293 * pool->lock is held and there's no work to process and no need to
2377 * need to manage, sleep. Workers are woken up only while 2294 * manage, sleep. Workers are woken up only while holding
2378 * holding gcwq->lock or from local cpu, so setting the 2295 * pool->lock or from local cpu, so setting the current state
2379 * current state before releasing gcwq->lock is enough to 2296 * before releasing pool->lock is enough to prevent losing any
2380 * prevent losing any event. 2297 * event.
2381 */ 2298 */
2382 worker_enter_idle(worker); 2299 worker_enter_idle(worker);
2383 __set_current_state(TASK_INTERRUPTIBLE); 2300 __set_current_state(TASK_INTERRUPTIBLE);
2384 spin_unlock_irq(&gcwq->lock); 2301 spin_unlock_irq(&pool->lock);
2385 schedule(); 2302 schedule();
2386 goto woke_up; 2303 goto woke_up;
2387} 2304}
2388 2305
2389/** 2306/**
2390 * rescuer_thread - the rescuer thread function 2307 * rescuer_thread - the rescuer thread function
2391 * @__wq: the associated workqueue 2308 * @__rescuer: self
2392 * 2309 *
2393 * Workqueue rescuer thread function. There's one rescuer for each 2310 * Workqueue rescuer thread function. There's one rescuer for each
2394 * workqueue which has WQ_RESCUER set. 2311 * workqueue which has WQ_RESCUER set.
2395 * 2312 *
2396 * Regular work processing on a gcwq may block trying to create a new 2313 * Regular work processing on a pool may block trying to create a new
2397 * worker which uses GFP_KERNEL allocation which has slight chance of 2314 * worker which uses GFP_KERNEL allocation which has slight chance of
2398 * developing into deadlock if some works currently on the same queue 2315 * developing into deadlock if some works currently on the same queue
2399 * need to be processed to satisfy the GFP_KERNEL allocation. This is 2316 * need to be processed to satisfy the GFP_KERNEL allocation. This is
2400 * the problem rescuer solves. 2317 * the problem rescuer solves.
2401 * 2318 *
2402 * When such condition is possible, the gcwq summons rescuers of all 2319 * When such condition is possible, the pool summons rescuers of all
2403 * workqueues which have works queued on the gcwq and let them process 2320 * workqueues which have works queued on the pool and let them process
2404 * those works so that forward progress can be guaranteed. 2321 * those works so that forward progress can be guaranteed.
2405 * 2322 *
2406 * This should happen rarely. 2323 * This should happen rarely.
2407 */ 2324 */
2408static int rescuer_thread(void *__wq) 2325static int rescuer_thread(void *__rescuer)
2409{ 2326{
2410 struct workqueue_struct *wq = __wq; 2327 struct worker *rescuer = __rescuer;
2411 struct worker *rescuer = wq->rescuer; 2328 struct workqueue_struct *wq = rescuer->rescue_wq;
2412 struct list_head *scheduled = &rescuer->scheduled; 2329 struct list_head *scheduled = &rescuer->scheduled;
2413 bool is_unbound = wq->flags & WQ_UNBOUND; 2330 bool is_unbound = wq->flags & WQ_UNBOUND;
2414 unsigned int cpu; 2331 unsigned int cpu;
2415 2332
2416 set_user_nice(current, RESCUER_NICE_LEVEL); 2333 set_user_nice(current, RESCUER_NICE_LEVEL);
2334
2335 /*
2336 * Mark rescuer as worker too. As WORKER_PREP is never cleared, it
2337 * doesn't participate in concurrency management.
2338 */
2339 rescuer->task->flags |= PF_WQ_WORKER;
2417repeat: 2340repeat:
2418 set_current_state(TASK_INTERRUPTIBLE); 2341 set_current_state(TASK_INTERRUPTIBLE);
2419 2342
2420 if (kthread_should_stop()) { 2343 if (kthread_should_stop()) {
2421 __set_current_state(TASK_RUNNING); 2344 __set_current_state(TASK_RUNNING);
2345 rescuer->task->flags &= ~PF_WQ_WORKER;
2422 return 0; 2346 return 0;
2423 } 2347 }
2424 2348
@@ -2428,9 +2352,8 @@ repeat:
2428 */ 2352 */
2429 for_each_mayday_cpu(cpu, wq->mayday_mask) { 2353 for_each_mayday_cpu(cpu, wq->mayday_mask) {
2430 unsigned int tcpu = is_unbound ? WORK_CPU_UNBOUND : cpu; 2354 unsigned int tcpu = is_unbound ? WORK_CPU_UNBOUND : cpu;
2431 struct cpu_workqueue_struct *cwq = get_cwq(tcpu, wq); 2355 struct pool_workqueue *pwq = get_pwq(tcpu, wq);
2432 struct worker_pool *pool = cwq->pool; 2356 struct worker_pool *pool = pwq->pool;
2433 struct global_cwq *gcwq = pool->gcwq;
2434 struct work_struct *work, *n; 2357 struct work_struct *work, *n;
2435 2358
2436 __set_current_state(TASK_RUNNING); 2359 __set_current_state(TASK_RUNNING);
@@ -2446,22 +2369,24 @@ repeat:
2446 */ 2369 */
2447 BUG_ON(!list_empty(&rescuer->scheduled)); 2370 BUG_ON(!list_empty(&rescuer->scheduled));
2448 list_for_each_entry_safe(work, n, &pool->worklist, entry) 2371 list_for_each_entry_safe(work, n, &pool->worklist, entry)
2449 if (get_work_cwq(work) == cwq) 2372 if (get_work_pwq(work) == pwq)
2450 move_linked_works(work, scheduled, &n); 2373 move_linked_works(work, scheduled, &n);
2451 2374
2452 process_scheduled_works(rescuer); 2375 process_scheduled_works(rescuer);
2453 2376
2454 /* 2377 /*
2455 * Leave this gcwq. If keep_working() is %true, notify a 2378 * Leave this pool. If keep_working() is %true, notify a
2456 * regular worker; otherwise, we end up with 0 concurrency 2379 * regular worker; otherwise, we end up with 0 concurrency
2457 * and stalling the execution. 2380 * and stalling the execution.
2458 */ 2381 */
2459 if (keep_working(pool)) 2382 if (keep_working(pool))
2460 wake_up_worker(pool); 2383 wake_up_worker(pool);
2461 2384
2462 spin_unlock_irq(&gcwq->lock); 2385 spin_unlock_irq(&pool->lock);
2463 } 2386 }
2464 2387
2388 /* rescuers should never participate in concurrency management */
2389 WARN_ON_ONCE(!(rescuer->flags & WORKER_NOT_RUNNING));
2465 schedule(); 2390 schedule();
2466 goto repeat; 2391 goto repeat;
2467} 2392}
@@ -2479,7 +2404,7 @@ static void wq_barrier_func(struct work_struct *work)
2479 2404
2480/** 2405/**
2481 * insert_wq_barrier - insert a barrier work 2406 * insert_wq_barrier - insert a barrier work
2482 * @cwq: cwq to insert barrier into 2407 * @pwq: pwq to insert barrier into
2483 * @barr: wq_barrier to insert 2408 * @barr: wq_barrier to insert
2484 * @target: target work to attach @barr to 2409 * @target: target work to attach @barr to
2485 * @worker: worker currently executing @target, NULL if @target is not executing 2410 * @worker: worker currently executing @target, NULL if @target is not executing
@@ -2496,12 +2421,12 @@ static void wq_barrier_func(struct work_struct *work)
2496 * after a work with LINKED flag set. 2421 * after a work with LINKED flag set.
2497 * 2422 *
2498 * Note that when @worker is non-NULL, @target may be modified 2423 * Note that when @worker is non-NULL, @target may be modified
2499 * underneath us, so we can't reliably determine cwq from @target. 2424 * underneath us, so we can't reliably determine pwq from @target.
2500 * 2425 *
2501 * CONTEXT: 2426 * CONTEXT:
2502 * spin_lock_irq(gcwq->lock). 2427 * spin_lock_irq(pool->lock).
2503 */ 2428 */
2504static void insert_wq_barrier(struct cpu_workqueue_struct *cwq, 2429static void insert_wq_barrier(struct pool_workqueue *pwq,
2505 struct wq_barrier *barr, 2430 struct wq_barrier *barr,
2506 struct work_struct *target, struct worker *worker) 2431 struct work_struct *target, struct worker *worker)
2507{ 2432{
@@ -2509,7 +2434,7 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
2509 unsigned int linked = 0; 2434 unsigned int linked = 0;
2510 2435
2511 /* 2436 /*
2512 * debugobject calls are safe here even with gcwq->lock locked 2437 * debugobject calls are safe here even with pool->lock locked
2513 * as we know for sure that this will not trigger any of the 2438 * as we know for sure that this will not trigger any of the
2514 * checks and call back into the fixup functions where we 2439 * checks and call back into the fixup functions where we
2515 * might deadlock. 2440 * might deadlock.
@@ -2534,23 +2459,23 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
2534 } 2459 }
2535 2460
2536 debug_work_activate(&barr->work); 2461 debug_work_activate(&barr->work);
2537 insert_work(cwq, &barr->work, head, 2462 insert_work(pwq, &barr->work, head,
2538 work_color_to_flags(WORK_NO_COLOR) | linked); 2463 work_color_to_flags(WORK_NO_COLOR) | linked);
2539} 2464}
2540 2465
2541/** 2466/**
2542 * flush_workqueue_prep_cwqs - prepare cwqs for workqueue flushing 2467 * flush_workqueue_prep_pwqs - prepare pwqs for workqueue flushing
2543 * @wq: workqueue being flushed 2468 * @wq: workqueue being flushed
2544 * @flush_color: new flush color, < 0 for no-op 2469 * @flush_color: new flush color, < 0 for no-op
2545 * @work_color: new work color, < 0 for no-op 2470 * @work_color: new work color, < 0 for no-op
2546 * 2471 *
2547 * Prepare cwqs for workqueue flushing. 2472 * Prepare pwqs for workqueue flushing.
2548 * 2473 *
2549 * If @flush_color is non-negative, flush_color on all cwqs should be 2474 * If @flush_color is non-negative, flush_color on all pwqs should be
2550 * -1. If no cwq has in-flight commands at the specified color, all 2475 * -1. If no pwq has in-flight commands at the specified color, all
2551 * cwq->flush_color's stay at -1 and %false is returned. If any cwq 2476 * pwq->flush_color's stay at -1 and %false is returned. If any pwq
2552 * has in flight commands, its cwq->flush_color is set to 2477 * has in flight commands, its pwq->flush_color is set to
2553 * @flush_color, @wq->nr_cwqs_to_flush is updated accordingly, cwq 2478 * @flush_color, @wq->nr_pwqs_to_flush is updated accordingly, pwq
2554 * wakeup logic is armed and %true is returned. 2479 * wakeup logic is armed and %true is returned.
2555 * 2480 *
2556 * The caller should have initialized @wq->first_flusher prior to 2481 * The caller should have initialized @wq->first_flusher prior to
@@ -2558,7 +2483,7 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
2558 * @flush_color is negative, no flush color update is done and %false 2483 * @flush_color is negative, no flush color update is done and %false
2559 * is returned. 2484 * is returned.
2560 * 2485 *
2561 * If @work_color is non-negative, all cwqs should have the same 2486 * If @work_color is non-negative, all pwqs should have the same
2562 * work_color which is previous to @work_color and all will be 2487 * work_color which is previous to @work_color and all will be
2563 * advanced to @work_color. 2488 * advanced to @work_color.
2564 * 2489 *
@@ -2569,42 +2494,42 @@ static void insert_wq_barrier(struct cpu_workqueue_struct *cwq,
2569 * %true if @flush_color >= 0 and there's something to flush. %false 2494 * %true if @flush_color >= 0 and there's something to flush. %false
2570 * otherwise. 2495 * otherwise.
2571 */ 2496 */
2572static bool flush_workqueue_prep_cwqs(struct workqueue_struct *wq, 2497static bool flush_workqueue_prep_pwqs(struct workqueue_struct *wq,
2573 int flush_color, int work_color) 2498 int flush_color, int work_color)
2574{ 2499{
2575 bool wait = false; 2500 bool wait = false;
2576 unsigned int cpu; 2501 unsigned int cpu;
2577 2502
2578 if (flush_color >= 0) { 2503 if (flush_color >= 0) {
2579 BUG_ON(atomic_read(&wq->nr_cwqs_to_flush)); 2504 BUG_ON(atomic_read(&wq->nr_pwqs_to_flush));
2580 atomic_set(&wq->nr_cwqs_to_flush, 1); 2505 atomic_set(&wq->nr_pwqs_to_flush, 1);
2581 } 2506 }
2582 2507
2583 for_each_cwq_cpu(cpu, wq) { 2508 for_each_pwq_cpu(cpu, wq) {
2584 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 2509 struct pool_workqueue *pwq = get_pwq(cpu, wq);
2585 struct global_cwq *gcwq = cwq->pool->gcwq; 2510 struct worker_pool *pool = pwq->pool;
2586 2511
2587 spin_lock_irq(&gcwq->lock); 2512 spin_lock_irq(&pool->lock);
2588 2513
2589 if (flush_color >= 0) { 2514 if (flush_color >= 0) {
2590 BUG_ON(cwq->flush_color != -1); 2515 BUG_ON(pwq->flush_color != -1);
2591 2516
2592 if (cwq->nr_in_flight[flush_color]) { 2517 if (pwq->nr_in_flight[flush_color]) {
2593 cwq->flush_color = flush_color; 2518 pwq->flush_color = flush_color;
2594 atomic_inc(&wq->nr_cwqs_to_flush); 2519 atomic_inc(&wq->nr_pwqs_to_flush);
2595 wait = true; 2520 wait = true;
2596 } 2521 }
2597 } 2522 }
2598 2523
2599 if (work_color >= 0) { 2524 if (work_color >= 0) {
2600 BUG_ON(work_color != work_next_color(cwq->work_color)); 2525 BUG_ON(work_color != work_next_color(pwq->work_color));
2601 cwq->work_color = work_color; 2526 pwq->work_color = work_color;
2602 } 2527 }
2603 2528
2604 spin_unlock_irq(&gcwq->lock); 2529 spin_unlock_irq(&pool->lock);
2605 } 2530 }
2606 2531
2607 if (flush_color >= 0 && atomic_dec_and_test(&wq->nr_cwqs_to_flush)) 2532 if (flush_color >= 0 && atomic_dec_and_test(&wq->nr_pwqs_to_flush))
2608 complete(&wq->first_flusher->done); 2533 complete(&wq->first_flusher->done);
2609 2534
2610 return wait; 2535 return wait;
@@ -2655,7 +2580,7 @@ void flush_workqueue(struct workqueue_struct *wq)
2655 2580
2656 wq->first_flusher = &this_flusher; 2581 wq->first_flusher = &this_flusher;
2657 2582
2658 if (!flush_workqueue_prep_cwqs(wq, wq->flush_color, 2583 if (!flush_workqueue_prep_pwqs(wq, wq->flush_color,
2659 wq->work_color)) { 2584 wq->work_color)) {
2660 /* nothing to flush, done */ 2585 /* nothing to flush, done */
2661 wq->flush_color = next_color; 2586 wq->flush_color = next_color;
@@ -2666,7 +2591,7 @@ void flush_workqueue(struct workqueue_struct *wq)
2666 /* wait in queue */ 2591 /* wait in queue */
2667 BUG_ON(wq->flush_color == this_flusher.flush_color); 2592 BUG_ON(wq->flush_color == this_flusher.flush_color);
2668 list_add_tail(&this_flusher.list, &wq->flusher_queue); 2593 list_add_tail(&this_flusher.list, &wq->flusher_queue);
2669 flush_workqueue_prep_cwqs(wq, -1, wq->work_color); 2594 flush_workqueue_prep_pwqs(wq, -1, wq->work_color);
2670 } 2595 }
2671 } else { 2596 } else {
2672 /* 2597 /*
@@ -2733,7 +2658,7 @@ void flush_workqueue(struct workqueue_struct *wq)
2733 2658
2734 list_splice_tail_init(&wq->flusher_overflow, 2659 list_splice_tail_init(&wq->flusher_overflow,
2735 &wq->flusher_queue); 2660 &wq->flusher_queue);
2736 flush_workqueue_prep_cwqs(wq, -1, wq->work_color); 2661 flush_workqueue_prep_pwqs(wq, -1, wq->work_color);
2737 } 2662 }
2738 2663
2739 if (list_empty(&wq->flusher_queue)) { 2664 if (list_empty(&wq->flusher_queue)) {
@@ -2743,7 +2668,7 @@ void flush_workqueue(struct workqueue_struct *wq)
2743 2668
2744 /* 2669 /*
2745 * Need to flush more colors. Make the next flusher 2670 * Need to flush more colors. Make the next flusher
2746 * the new first flusher and arm cwqs. 2671 * the new first flusher and arm pwqs.
2747 */ 2672 */
2748 BUG_ON(wq->flush_color == wq->work_color); 2673 BUG_ON(wq->flush_color == wq->work_color);
2749 BUG_ON(wq->flush_color != next->flush_color); 2674 BUG_ON(wq->flush_color != next->flush_color);
@@ -2751,7 +2676,7 @@ void flush_workqueue(struct workqueue_struct *wq)
2751 list_del_init(&next->list); 2676 list_del_init(&next->list);
2752 wq->first_flusher = next; 2677 wq->first_flusher = next;
2753 2678
2754 if (flush_workqueue_prep_cwqs(wq, wq->flush_color, -1)) 2679 if (flush_workqueue_prep_pwqs(wq, wq->flush_color, -1))
2755 break; 2680 break;
2756 2681
2757 /* 2682 /*
@@ -2794,13 +2719,13 @@ void drain_workqueue(struct workqueue_struct *wq)
2794reflush: 2719reflush:
2795 flush_workqueue(wq); 2720 flush_workqueue(wq);
2796 2721
2797 for_each_cwq_cpu(cpu, wq) { 2722 for_each_pwq_cpu(cpu, wq) {
2798 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 2723 struct pool_workqueue *pwq = get_pwq(cpu, wq);
2799 bool drained; 2724 bool drained;
2800 2725
2801 spin_lock_irq(&cwq->pool->gcwq->lock); 2726 spin_lock_irq(&pwq->pool->lock);
2802 drained = !cwq->nr_active && list_empty(&cwq->delayed_works); 2727 drained = !pwq->nr_active && list_empty(&pwq->delayed_works);
2803 spin_unlock_irq(&cwq->pool->gcwq->lock); 2728 spin_unlock_irq(&pwq->pool->lock);
2804 2729
2805 if (drained) 2730 if (drained)
2806 continue; 2731 continue;
@@ -2822,34 +2747,29 @@ EXPORT_SYMBOL_GPL(drain_workqueue);
2822static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr) 2747static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
2823{ 2748{
2824 struct worker *worker = NULL; 2749 struct worker *worker = NULL;
2825 struct global_cwq *gcwq; 2750 struct worker_pool *pool;
2826 struct cpu_workqueue_struct *cwq; 2751 struct pool_workqueue *pwq;
2827 2752
2828 might_sleep(); 2753 might_sleep();
2829 gcwq = get_work_gcwq(work); 2754 pool = get_work_pool(work);
2830 if (!gcwq) 2755 if (!pool)
2831 return false; 2756 return false;
2832 2757
2833 spin_lock_irq(&gcwq->lock); 2758 spin_lock_irq(&pool->lock);
2834 if (!list_empty(&work->entry)) { 2759 /* see the comment in try_to_grab_pending() with the same code */
2835 /* 2760 pwq = get_work_pwq(work);
2836 * See the comment near try_to_grab_pending()->smp_rmb(). 2761 if (pwq) {
2837 * If it was re-queued to a different gcwq under us, we 2762 if (unlikely(pwq->pool != pool))
2838 * are not going to wait.
2839 */
2840 smp_rmb();
2841 cwq = get_work_cwq(work);
2842 if (unlikely(!cwq || gcwq != cwq->pool->gcwq))
2843 goto already_gone; 2763 goto already_gone;
2844 } else { 2764 } else {
2845 worker = find_worker_executing_work(gcwq, work); 2765 worker = find_worker_executing_work(pool, work);
2846 if (!worker) 2766 if (!worker)
2847 goto already_gone; 2767 goto already_gone;
2848 cwq = worker->current_cwq; 2768 pwq = worker->current_pwq;
2849 } 2769 }
2850 2770
2851 insert_wq_barrier(cwq, barr, work, worker); 2771 insert_wq_barrier(pwq, barr, work, worker);
2852 spin_unlock_irq(&gcwq->lock); 2772 spin_unlock_irq(&pool->lock);
2853 2773
2854 /* 2774 /*
2855 * If @max_active is 1 or rescuer is in use, flushing another work 2775 * If @max_active is 1 or rescuer is in use, flushing another work
@@ -2857,15 +2777,15 @@ static bool start_flush_work(struct work_struct *work, struct wq_barrier *barr)
2857 * flusher is not running on the same workqueue by verifying write 2777 * flusher is not running on the same workqueue by verifying write
2858 * access. 2778 * access.
2859 */ 2779 */
2860 if (cwq->wq->saved_max_active == 1 || cwq->wq->flags & WQ_RESCUER) 2780 if (pwq->wq->saved_max_active == 1 || pwq->wq->flags & WQ_RESCUER)
2861 lock_map_acquire(&cwq->wq->lockdep_map); 2781 lock_map_acquire(&pwq->wq->lockdep_map);
2862 else 2782 else
2863 lock_map_acquire_read(&cwq->wq->lockdep_map); 2783 lock_map_acquire_read(&pwq->wq->lockdep_map);
2864 lock_map_release(&cwq->wq->lockdep_map); 2784 lock_map_release(&pwq->wq->lockdep_map);
2865 2785
2866 return true; 2786 return true;
2867already_gone: 2787already_gone:
2868 spin_unlock_irq(&gcwq->lock); 2788 spin_unlock_irq(&pool->lock);
2869 return false; 2789 return false;
2870} 2790}
2871 2791
@@ -2961,8 +2881,7 @@ bool flush_delayed_work(struct delayed_work *dwork)
2961{ 2881{
2962 local_irq_disable(); 2882 local_irq_disable();
2963 if (del_timer_sync(&dwork->timer)) 2883 if (del_timer_sync(&dwork->timer))
2964 __queue_work(dwork->cpu, 2884 __queue_work(dwork->cpu, dwork->wq, &dwork->work);
2965 get_work_cwq(&dwork->work)->wq, &dwork->work);
2966 local_irq_enable(); 2885 local_irq_enable();
2967 return flush_work(&dwork->work); 2886 return flush_work(&dwork->work);
2968} 2887}
@@ -2992,7 +2911,8 @@ bool cancel_delayed_work(struct delayed_work *dwork)
2992 if (unlikely(ret < 0)) 2911 if (unlikely(ret < 0))
2993 return false; 2912 return false;
2994 2913
2995 set_work_cpu_and_clear_pending(&dwork->work, work_cpu(&dwork->work)); 2914 set_work_pool_and_clear_pending(&dwork->work,
2915 get_work_pool_id(&dwork->work));
2996 local_irq_restore(flags); 2916 local_irq_restore(flags);
2997 return ret; 2917 return ret;
2998} 2918}
@@ -3171,46 +3091,46 @@ int keventd_up(void)
3171 return system_wq != NULL; 3091 return system_wq != NULL;
3172} 3092}
3173 3093
3174static int alloc_cwqs(struct workqueue_struct *wq) 3094static int alloc_pwqs(struct workqueue_struct *wq)
3175{ 3095{
3176 /* 3096 /*
3177 * cwqs are forced aligned according to WORK_STRUCT_FLAG_BITS. 3097 * pwqs are forced aligned according to WORK_STRUCT_FLAG_BITS.
3178 * Make sure that the alignment isn't lower than that of 3098 * Make sure that the alignment isn't lower than that of
3179 * unsigned long long. 3099 * unsigned long long.
3180 */ 3100 */
3181 const size_t size = sizeof(struct cpu_workqueue_struct); 3101 const size_t size = sizeof(struct pool_workqueue);
3182 const size_t align = max_t(size_t, 1 << WORK_STRUCT_FLAG_BITS, 3102 const size_t align = max_t(size_t, 1 << WORK_STRUCT_FLAG_BITS,
3183 __alignof__(unsigned long long)); 3103 __alignof__(unsigned long long));
3184 3104
3185 if (!(wq->flags & WQ_UNBOUND)) 3105 if (!(wq->flags & WQ_UNBOUND))
3186 wq->cpu_wq.pcpu = __alloc_percpu(size, align); 3106 wq->pool_wq.pcpu = __alloc_percpu(size, align);
3187 else { 3107 else {
3188 void *ptr; 3108 void *ptr;
3189 3109
3190 /* 3110 /*
3191 * Allocate enough room to align cwq and put an extra 3111 * Allocate enough room to align pwq and put an extra
3192 * pointer at the end pointing back to the originally 3112 * pointer at the end pointing back to the originally
3193 * allocated pointer which will be used for free. 3113 * allocated pointer which will be used for free.
3194 */ 3114 */
3195 ptr = kzalloc(size + align + sizeof(void *), GFP_KERNEL); 3115 ptr = kzalloc(size + align + sizeof(void *), GFP_KERNEL);
3196 if (ptr) { 3116 if (ptr) {
3197 wq->cpu_wq.single = PTR_ALIGN(ptr, align); 3117 wq->pool_wq.single = PTR_ALIGN(ptr, align);
3198 *(void **)(wq->cpu_wq.single + 1) = ptr; 3118 *(void **)(wq->pool_wq.single + 1) = ptr;
3199 } 3119 }
3200 } 3120 }
3201 3121
3202 /* just in case, make sure it's actually aligned */ 3122 /* just in case, make sure it's actually aligned */
3203 BUG_ON(!IS_ALIGNED(wq->cpu_wq.v, align)); 3123 BUG_ON(!IS_ALIGNED(wq->pool_wq.v, align));
3204 return wq->cpu_wq.v ? 0 : -ENOMEM; 3124 return wq->pool_wq.v ? 0 : -ENOMEM;
3205} 3125}
3206 3126
3207static void free_cwqs(struct workqueue_struct *wq) 3127static void free_pwqs(struct workqueue_struct *wq)
3208{ 3128{
3209 if (!(wq->flags & WQ_UNBOUND)) 3129 if (!(wq->flags & WQ_UNBOUND))
3210 free_percpu(wq->cpu_wq.pcpu); 3130 free_percpu(wq->pool_wq.pcpu);
3211 else if (wq->cpu_wq.single) { 3131 else if (wq->pool_wq.single) {
3212 /* the pointer to free is stored right after the cwq */ 3132 /* the pointer to free is stored right after the pwq */
3213 kfree(*(void **)(wq->cpu_wq.single + 1)); 3133 kfree(*(void **)(wq->pool_wq.single + 1));
3214 } 3134 }
3215} 3135}
3216 3136
@@ -3264,27 +3184,25 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
3264 wq->flags = flags; 3184 wq->flags = flags;
3265 wq->saved_max_active = max_active; 3185 wq->saved_max_active = max_active;
3266 mutex_init(&wq->flush_mutex); 3186 mutex_init(&wq->flush_mutex);
3267 atomic_set(&wq->nr_cwqs_to_flush, 0); 3187 atomic_set(&wq->nr_pwqs_to_flush, 0);
3268 INIT_LIST_HEAD(&wq->flusher_queue); 3188 INIT_LIST_HEAD(&wq->flusher_queue);
3269 INIT_LIST_HEAD(&wq->flusher_overflow); 3189 INIT_LIST_HEAD(&wq->flusher_overflow);
3270 3190
3271 lockdep_init_map(&wq->lockdep_map, lock_name, key, 0); 3191 lockdep_init_map(&wq->lockdep_map, lock_name, key, 0);
3272 INIT_LIST_HEAD(&wq->list); 3192 INIT_LIST_HEAD(&wq->list);
3273 3193
3274 if (alloc_cwqs(wq) < 0) 3194 if (alloc_pwqs(wq) < 0)
3275 goto err; 3195 goto err;
3276 3196
3277 for_each_cwq_cpu(cpu, wq) { 3197 for_each_pwq_cpu(cpu, wq) {
3278 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3198 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3279 struct global_cwq *gcwq = get_gcwq(cpu); 3199
3280 int pool_idx = (bool)(flags & WQ_HIGHPRI); 3200 BUG_ON((unsigned long)pwq & WORK_STRUCT_FLAG_MASK);
3281 3201 pwq->pool = get_std_worker_pool(cpu, flags & WQ_HIGHPRI);
3282 BUG_ON((unsigned long)cwq & WORK_STRUCT_FLAG_MASK); 3202 pwq->wq = wq;
3283 cwq->pool = &gcwq->pools[pool_idx]; 3203 pwq->flush_color = -1;
3284 cwq->wq = wq; 3204 pwq->max_active = max_active;
3285 cwq->flush_color = -1; 3205 INIT_LIST_HEAD(&pwq->delayed_works);
3286 cwq->max_active = max_active;
3287 INIT_LIST_HEAD(&cwq->delayed_works);
3288 } 3206 }
3289 3207
3290 if (flags & WQ_RESCUER) { 3208 if (flags & WQ_RESCUER) {
@@ -3297,7 +3215,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
3297 if (!rescuer) 3215 if (!rescuer)
3298 goto err; 3216 goto err;
3299 3217
3300 rescuer->task = kthread_create(rescuer_thread, wq, "%s", 3218 rescuer->rescue_wq = wq;
3219 rescuer->task = kthread_create(rescuer_thread, rescuer, "%s",
3301 wq->name); 3220 wq->name);
3302 if (IS_ERR(rescuer->task)) 3221 if (IS_ERR(rescuer->task))
3303 goto err; 3222 goto err;
@@ -3314,8 +3233,8 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
3314 spin_lock(&workqueue_lock); 3233 spin_lock(&workqueue_lock);
3315 3234
3316 if (workqueue_freezing && wq->flags & WQ_FREEZABLE) 3235 if (workqueue_freezing && wq->flags & WQ_FREEZABLE)
3317 for_each_cwq_cpu(cpu, wq) 3236 for_each_pwq_cpu(cpu, wq)
3318 get_cwq(cpu, wq)->max_active = 0; 3237 get_pwq(cpu, wq)->max_active = 0;
3319 3238
3320 list_add(&wq->list, &workqueues); 3239 list_add(&wq->list, &workqueues);
3321 3240
@@ -3324,7 +3243,7 @@ struct workqueue_struct *__alloc_workqueue_key(const char *fmt,
3324 return wq; 3243 return wq;
3325err: 3244err:
3326 if (wq) { 3245 if (wq) {
3327 free_cwqs(wq); 3246 free_pwqs(wq);
3328 free_mayday_mask(wq->mayday_mask); 3247 free_mayday_mask(wq->mayday_mask);
3329 kfree(wq->rescuer); 3248 kfree(wq->rescuer);
3330 kfree(wq); 3249 kfree(wq);
@@ -3355,14 +3274,14 @@ void destroy_workqueue(struct workqueue_struct *wq)
3355 spin_unlock(&workqueue_lock); 3274 spin_unlock(&workqueue_lock);
3356 3275
3357 /* sanity check */ 3276 /* sanity check */
3358 for_each_cwq_cpu(cpu, wq) { 3277 for_each_pwq_cpu(cpu, wq) {
3359 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3278 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3360 int i; 3279 int i;
3361 3280
3362 for (i = 0; i < WORK_NR_COLORS; i++) 3281 for (i = 0; i < WORK_NR_COLORS; i++)
3363 BUG_ON(cwq->nr_in_flight[i]); 3282 BUG_ON(pwq->nr_in_flight[i]);
3364 BUG_ON(cwq->nr_active); 3283 BUG_ON(pwq->nr_active);
3365 BUG_ON(!list_empty(&cwq->delayed_works)); 3284 BUG_ON(!list_empty(&pwq->delayed_works));
3366 } 3285 }
3367 3286
3368 if (wq->flags & WQ_RESCUER) { 3287 if (wq->flags & WQ_RESCUER) {
@@ -3371,29 +3290,29 @@ void destroy_workqueue(struct workqueue_struct *wq)
3371 kfree(wq->rescuer); 3290 kfree(wq->rescuer);
3372 } 3291 }
3373 3292
3374 free_cwqs(wq); 3293 free_pwqs(wq);
3375 kfree(wq); 3294 kfree(wq);
3376} 3295}
3377EXPORT_SYMBOL_GPL(destroy_workqueue); 3296EXPORT_SYMBOL_GPL(destroy_workqueue);
3378 3297
3379/** 3298/**
3380 * cwq_set_max_active - adjust max_active of a cwq 3299 * pwq_set_max_active - adjust max_active of a pwq
3381 * @cwq: target cpu_workqueue_struct 3300 * @pwq: target pool_workqueue
3382 * @max_active: new max_active value. 3301 * @max_active: new max_active value.
3383 * 3302 *
3384 * Set @cwq->max_active to @max_active and activate delayed works if 3303 * Set @pwq->max_active to @max_active and activate delayed works if
3385 * increased. 3304 * increased.
3386 * 3305 *
3387 * CONTEXT: 3306 * CONTEXT:
3388 * spin_lock_irq(gcwq->lock). 3307 * spin_lock_irq(pool->lock).
3389 */ 3308 */
3390static void cwq_set_max_active(struct cpu_workqueue_struct *cwq, int max_active) 3309static void pwq_set_max_active(struct pool_workqueue *pwq, int max_active)
3391{ 3310{
3392 cwq->max_active = max_active; 3311 pwq->max_active = max_active;
3393 3312
3394 while (!list_empty(&cwq->delayed_works) && 3313 while (!list_empty(&pwq->delayed_works) &&
3395 cwq->nr_active < cwq->max_active) 3314 pwq->nr_active < pwq->max_active)
3396 cwq_activate_first_delayed(cwq); 3315 pwq_activate_first_delayed(pwq);
3397} 3316}
3398 3317
3399/** 3318/**
@@ -3416,16 +3335,17 @@ void workqueue_set_max_active(struct workqueue_struct *wq, int max_active)
3416 3335
3417 wq->saved_max_active = max_active; 3336 wq->saved_max_active = max_active;
3418 3337
3419 for_each_cwq_cpu(cpu, wq) { 3338 for_each_pwq_cpu(cpu, wq) {
3420 struct global_cwq *gcwq = get_gcwq(cpu); 3339 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3340 struct worker_pool *pool = pwq->pool;
3421 3341
3422 spin_lock_irq(&gcwq->lock); 3342 spin_lock_irq(&pool->lock);
3423 3343
3424 if (!(wq->flags & WQ_FREEZABLE) || 3344 if (!(wq->flags & WQ_FREEZABLE) ||
3425 !(gcwq->flags & GCWQ_FREEZING)) 3345 !(pool->flags & POOL_FREEZING))
3426 cwq_set_max_active(get_cwq(gcwq->cpu, wq), max_active); 3346 pwq_set_max_active(pwq, max_active);
3427 3347
3428 spin_unlock_irq(&gcwq->lock); 3348 spin_unlock_irq(&pool->lock);
3429 } 3349 }
3430 3350
3431 spin_unlock(&workqueue_lock); 3351 spin_unlock(&workqueue_lock);
@@ -3446,57 +3366,38 @@ EXPORT_SYMBOL_GPL(workqueue_set_max_active);
3446 */ 3366 */
3447bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq) 3367bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq)
3448{ 3368{
3449 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3369 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3450 3370
3451 return !list_empty(&cwq->delayed_works); 3371 return !list_empty(&pwq->delayed_works);
3452} 3372}
3453EXPORT_SYMBOL_GPL(workqueue_congested); 3373EXPORT_SYMBOL_GPL(workqueue_congested);
3454 3374
3455/** 3375/**
3456 * work_cpu - return the last known associated cpu for @work
3457 * @work: the work of interest
3458 *
3459 * RETURNS:
3460 * CPU number if @work was ever queued. WORK_CPU_NONE otherwise.
3461 */
3462unsigned int work_cpu(struct work_struct *work)
3463{
3464 struct global_cwq *gcwq = get_work_gcwq(work);
3465
3466 return gcwq ? gcwq->cpu : WORK_CPU_NONE;
3467}
3468EXPORT_SYMBOL_GPL(work_cpu);
3469
3470/**
3471 * work_busy - test whether a work is currently pending or running 3376 * work_busy - test whether a work is currently pending or running
3472 * @work: the work to be tested 3377 * @work: the work to be tested
3473 * 3378 *
3474 * Test whether @work is currently pending or running. There is no 3379 * Test whether @work is currently pending or running. There is no
3475 * synchronization around this function and the test result is 3380 * synchronization around this function and the test result is
3476 * unreliable and only useful as advisory hints or for debugging. 3381 * unreliable and only useful as advisory hints or for debugging.
3477 * Especially for reentrant wqs, the pending state might hide the
3478 * running state.
3479 * 3382 *
3480 * RETURNS: 3383 * RETURNS:
3481 * OR'd bitmask of WORK_BUSY_* bits. 3384 * OR'd bitmask of WORK_BUSY_* bits.
3482 */ 3385 */
3483unsigned int work_busy(struct work_struct *work) 3386unsigned int work_busy(struct work_struct *work)
3484{ 3387{
3485 struct global_cwq *gcwq = get_work_gcwq(work); 3388 struct worker_pool *pool = get_work_pool(work);
3486 unsigned long flags; 3389 unsigned long flags;
3487 unsigned int ret = 0; 3390 unsigned int ret = 0;
3488 3391
3489 if (!gcwq)
3490 return 0;
3491
3492 spin_lock_irqsave(&gcwq->lock, flags);
3493
3494 if (work_pending(work)) 3392 if (work_pending(work))
3495 ret |= WORK_BUSY_PENDING; 3393 ret |= WORK_BUSY_PENDING;
3496 if (find_worker_executing_work(gcwq, work))
3497 ret |= WORK_BUSY_RUNNING;
3498 3394
3499 spin_unlock_irqrestore(&gcwq->lock, flags); 3395 if (pool) {
3396 spin_lock_irqsave(&pool->lock, flags);
3397 if (find_worker_executing_work(pool, work))
3398 ret |= WORK_BUSY_RUNNING;
3399 spin_unlock_irqrestore(&pool->lock, flags);
3400 }
3500 3401
3501 return ret; 3402 return ret;
3502} 3403}
@@ -3506,65 +3407,49 @@ EXPORT_SYMBOL_GPL(work_busy);
3506 * CPU hotplug. 3407 * CPU hotplug.
3507 * 3408 *
3508 * There are two challenges in supporting CPU hotplug. Firstly, there 3409 * There are two challenges in supporting CPU hotplug. Firstly, there
3509 * are a lot of assumptions on strong associations among work, cwq and 3410 * are a lot of assumptions on strong associations among work, pwq and
3510 * gcwq which make migrating pending and scheduled works very 3411 * pool which make migrating pending and scheduled works very
3511 * difficult to implement without impacting hot paths. Secondly, 3412 * difficult to implement without impacting hot paths. Secondly,
3512 * gcwqs serve mix of short, long and very long running works making 3413 * worker pools serve mix of short, long and very long running works making
3513 * blocked draining impractical. 3414 * blocked draining impractical.
3514 * 3415 *
3515 * This is solved by allowing a gcwq to be disassociated from the CPU 3416 * This is solved by allowing the pools to be disassociated from the CPU
3516 * running as an unbound one and allowing it to be reattached later if the 3417 * running as an unbound one and allowing it to be reattached later if the
3517 * cpu comes back online. 3418 * cpu comes back online.
3518 */ 3419 */
3519 3420
3520/* claim manager positions of all pools */ 3421static void wq_unbind_fn(struct work_struct *work)
3521static void gcwq_claim_assoc_and_lock(struct global_cwq *gcwq)
3522{ 3422{
3523 struct worker_pool *pool; 3423 int cpu = smp_processor_id();
3524
3525 for_each_worker_pool(pool, gcwq)
3526 mutex_lock_nested(&pool->assoc_mutex, pool - gcwq->pools);
3527 spin_lock_irq(&gcwq->lock);
3528}
3529
3530/* release manager positions */
3531static void gcwq_release_assoc_and_unlock(struct global_cwq *gcwq)
3532{
3533 struct worker_pool *pool;
3534
3535 spin_unlock_irq(&gcwq->lock);
3536 for_each_worker_pool(pool, gcwq)
3537 mutex_unlock(&pool->assoc_mutex);
3538}
3539
3540static void gcwq_unbind_fn(struct work_struct *work)
3541{
3542 struct global_cwq *gcwq = get_gcwq(smp_processor_id());
3543 struct worker_pool *pool; 3424 struct worker_pool *pool;
3544 struct worker *worker; 3425 struct worker *worker;
3545 struct hlist_node *pos; 3426 struct hlist_node *pos;
3546 int i; 3427 int i;
3547 3428
3548 BUG_ON(gcwq->cpu != smp_processor_id()); 3429 for_each_std_worker_pool(pool, cpu) {
3430 BUG_ON(cpu != smp_processor_id());
3549 3431
3550 gcwq_claim_assoc_and_lock(gcwq); 3432 mutex_lock(&pool->assoc_mutex);
3433 spin_lock_irq(&pool->lock);
3551 3434
3552 /* 3435 /*
3553 * We've claimed all manager positions. Make all workers unbound 3436 * We've claimed all manager positions. Make all workers
3554 * and set DISASSOCIATED. Before this, all workers except for the 3437 * unbound and set DISASSOCIATED. Before this, all workers
3555 * ones which are still executing works from before the last CPU 3438 * except for the ones which are still executing works from
3556 * down must be on the cpu. After this, they may become diasporas. 3439 * before the last CPU down must be on the cpu. After
3557 */ 3440 * this, they may become diasporas.
3558 for_each_worker_pool(pool, gcwq) 3441 */
3559 list_for_each_entry(worker, &pool->idle_list, entry) 3442 list_for_each_entry(worker, &pool->idle_list, entry)
3560 worker->flags |= WORKER_UNBOUND; 3443 worker->flags |= WORKER_UNBOUND;
3561 3444
3562 for_each_busy_worker(worker, i, pos, gcwq) 3445 for_each_busy_worker(worker, i, pos, pool)
3563 worker->flags |= WORKER_UNBOUND; 3446 worker->flags |= WORKER_UNBOUND;
3564 3447
3565 gcwq->flags |= GCWQ_DISASSOCIATED; 3448 pool->flags |= POOL_DISASSOCIATED;
3566 3449
3567 gcwq_release_assoc_and_unlock(gcwq); 3450 spin_unlock_irq(&pool->lock);
3451 mutex_unlock(&pool->assoc_mutex);
3452 }
3568 3453
3569 /* 3454 /*
3570 * Call schedule() so that we cross rq->lock and thus can guarantee 3455 * Call schedule() so that we cross rq->lock and thus can guarantee
@@ -3576,16 +3461,16 @@ static void gcwq_unbind_fn(struct work_struct *work)
3576 /* 3461 /*
3577 * Sched callbacks are disabled now. Zap nr_running. After this, 3462 * Sched callbacks are disabled now. Zap nr_running. After this,
3578 * nr_running stays zero and need_more_worker() and keep_working() 3463 * nr_running stays zero and need_more_worker() and keep_working()
3579 * are always true as long as the worklist is not empty. @gcwq now 3464 * are always true as long as the worklist is not empty. Pools on
3580 * behaves as unbound (in terms of concurrency management) gcwq 3465 * @cpu now behave as unbound (in terms of concurrency management)
3581 * which is served by workers tied to the CPU. 3466 * pools which are served by workers tied to the CPU.
3582 * 3467 *
3583 * On return from this function, the current worker would trigger 3468 * On return from this function, the current worker would trigger
3584 * unbound chain execution of pending work items if other workers 3469 * unbound chain execution of pending work items if other workers
3585 * didn't already. 3470 * didn't already.
3586 */ 3471 */
3587 for_each_worker_pool(pool, gcwq) 3472 for_each_std_worker_pool(pool, cpu)
3588 atomic_set(get_pool_nr_running(pool), 0); 3473 atomic_set(&pool->nr_running, 0);
3589} 3474}
3590 3475
3591/* 3476/*
@@ -3597,12 +3482,11 @@ static int __cpuinit workqueue_cpu_up_callback(struct notifier_block *nfb,
3597 void *hcpu) 3482 void *hcpu)
3598{ 3483{
3599 unsigned int cpu = (unsigned long)hcpu; 3484 unsigned int cpu = (unsigned long)hcpu;
3600 struct global_cwq *gcwq = get_gcwq(cpu);
3601 struct worker_pool *pool; 3485 struct worker_pool *pool;
3602 3486
3603 switch (action & ~CPU_TASKS_FROZEN) { 3487 switch (action & ~CPU_TASKS_FROZEN) {
3604 case CPU_UP_PREPARE: 3488 case CPU_UP_PREPARE:
3605 for_each_worker_pool(pool, gcwq) { 3489 for_each_std_worker_pool(pool, cpu) {
3606 struct worker *worker; 3490 struct worker *worker;
3607 3491
3608 if (pool->nr_workers) 3492 if (pool->nr_workers)
@@ -3612,18 +3496,24 @@ static int __cpuinit workqueue_cpu_up_callback(struct notifier_block *nfb,
3612 if (!worker) 3496 if (!worker)
3613 return NOTIFY_BAD; 3497 return NOTIFY_BAD;
3614 3498
3615 spin_lock_irq(&gcwq->lock); 3499 spin_lock_irq(&pool->lock);
3616 start_worker(worker); 3500 start_worker(worker);
3617 spin_unlock_irq(&gcwq->lock); 3501 spin_unlock_irq(&pool->lock);
3618 } 3502 }
3619 break; 3503 break;
3620 3504
3621 case CPU_DOWN_FAILED: 3505 case CPU_DOWN_FAILED:
3622 case CPU_ONLINE: 3506 case CPU_ONLINE:
3623 gcwq_claim_assoc_and_lock(gcwq); 3507 for_each_std_worker_pool(pool, cpu) {
3624 gcwq->flags &= ~GCWQ_DISASSOCIATED; 3508 mutex_lock(&pool->assoc_mutex);
3625 rebind_workers(gcwq); 3509 spin_lock_irq(&pool->lock);
3626 gcwq_release_assoc_and_unlock(gcwq); 3510
3511 pool->flags &= ~POOL_DISASSOCIATED;
3512 rebind_workers(pool);
3513
3514 spin_unlock_irq(&pool->lock);
3515 mutex_unlock(&pool->assoc_mutex);
3516 }
3627 break; 3517 break;
3628 } 3518 }
3629 return NOTIFY_OK; 3519 return NOTIFY_OK;
@@ -3643,7 +3533,7 @@ static int __cpuinit workqueue_cpu_down_callback(struct notifier_block *nfb,
3643 switch (action & ~CPU_TASKS_FROZEN) { 3533 switch (action & ~CPU_TASKS_FROZEN) {
3644 case CPU_DOWN_PREPARE: 3534 case CPU_DOWN_PREPARE:
3645 /* unbinding should happen on the local CPU */ 3535 /* unbinding should happen on the local CPU */
3646 INIT_WORK_ONSTACK(&unbind_work, gcwq_unbind_fn); 3536 INIT_WORK_ONSTACK(&unbind_work, wq_unbind_fn);
3647 queue_work_on(cpu, system_highpri_wq, &unbind_work); 3537 queue_work_on(cpu, system_highpri_wq, &unbind_work);
3648 flush_work(&unbind_work); 3538 flush_work(&unbind_work);
3649 break; 3539 break;
@@ -3696,10 +3586,10 @@ EXPORT_SYMBOL_GPL(work_on_cpu);
3696 * 3586 *
3697 * Start freezing workqueues. After this function returns, all freezable 3587 * Start freezing workqueues. After this function returns, all freezable
3698 * workqueues will queue new works to their frozen_works list instead of 3588 * workqueues will queue new works to their frozen_works list instead of
3699 * gcwq->worklist. 3589 * pool->worklist.
3700 * 3590 *
3701 * CONTEXT: 3591 * CONTEXT:
3702 * Grabs and releases workqueue_lock and gcwq->lock's. 3592 * Grabs and releases workqueue_lock and pool->lock's.
3703 */ 3593 */
3704void freeze_workqueues_begin(void) 3594void freeze_workqueues_begin(void)
3705{ 3595{
@@ -3710,23 +3600,26 @@ void freeze_workqueues_begin(void)
3710 BUG_ON(workqueue_freezing); 3600 BUG_ON(workqueue_freezing);
3711 workqueue_freezing = true; 3601 workqueue_freezing = true;
3712 3602
3713 for_each_gcwq_cpu(cpu) { 3603 for_each_wq_cpu(cpu) {
3714 struct global_cwq *gcwq = get_gcwq(cpu); 3604 struct worker_pool *pool;
3715 struct workqueue_struct *wq; 3605 struct workqueue_struct *wq;
3716 3606
3717 spin_lock_irq(&gcwq->lock); 3607 for_each_std_worker_pool(pool, cpu) {
3608 spin_lock_irq(&pool->lock);
3718 3609
3719 BUG_ON(gcwq->flags & GCWQ_FREEZING); 3610 WARN_ON_ONCE(pool->flags & POOL_FREEZING);
3720 gcwq->flags |= GCWQ_FREEZING; 3611 pool->flags |= POOL_FREEZING;
3721 3612
3722 list_for_each_entry(wq, &workqueues, list) { 3613 list_for_each_entry(wq, &workqueues, list) {
3723 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3614 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3724 3615
3725 if (cwq && wq->flags & WQ_FREEZABLE) 3616 if (pwq && pwq->pool == pool &&
3726 cwq->max_active = 0; 3617 (wq->flags & WQ_FREEZABLE))
3727 } 3618 pwq->max_active = 0;
3619 }
3728 3620
3729 spin_unlock_irq(&gcwq->lock); 3621 spin_unlock_irq(&pool->lock);
3622 }
3730 } 3623 }
3731 3624
3732 spin_unlock(&workqueue_lock); 3625 spin_unlock(&workqueue_lock);
@@ -3754,20 +3647,20 @@ bool freeze_workqueues_busy(void)
3754 3647
3755 BUG_ON(!workqueue_freezing); 3648 BUG_ON(!workqueue_freezing);
3756 3649
3757 for_each_gcwq_cpu(cpu) { 3650 for_each_wq_cpu(cpu) {
3758 struct workqueue_struct *wq; 3651 struct workqueue_struct *wq;
3759 /* 3652 /*
3760 * nr_active is monotonically decreasing. It's safe 3653 * nr_active is monotonically decreasing. It's safe
3761 * to peek without lock. 3654 * to peek without lock.
3762 */ 3655 */
3763 list_for_each_entry(wq, &workqueues, list) { 3656 list_for_each_entry(wq, &workqueues, list) {
3764 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3657 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3765 3658
3766 if (!cwq || !(wq->flags & WQ_FREEZABLE)) 3659 if (!pwq || !(wq->flags & WQ_FREEZABLE))
3767 continue; 3660 continue;
3768 3661
3769 BUG_ON(cwq->nr_active < 0); 3662 BUG_ON(pwq->nr_active < 0);
3770 if (cwq->nr_active) { 3663 if (pwq->nr_active) {
3771 busy = true; 3664 busy = true;
3772 goto out_unlock; 3665 goto out_unlock;
3773 } 3666 }
@@ -3782,10 +3675,10 @@ out_unlock:
3782 * thaw_workqueues - thaw workqueues 3675 * thaw_workqueues - thaw workqueues
3783 * 3676 *
3784 * Thaw workqueues. Normal queueing is restored and all collected 3677 * Thaw workqueues. Normal queueing is restored and all collected
3785 * frozen works are transferred to their respective gcwq worklists. 3678 * frozen works are transferred to their respective pool worklists.
3786 * 3679 *
3787 * CONTEXT: 3680 * CONTEXT:
3788 * Grabs and releases workqueue_lock and gcwq->lock's. 3681 * Grabs and releases workqueue_lock and pool->lock's.
3789 */ 3682 */
3790void thaw_workqueues(void) 3683void thaw_workqueues(void)
3791{ 3684{
@@ -3796,30 +3689,31 @@ void thaw_workqueues(void)
3796 if (!workqueue_freezing) 3689 if (!workqueue_freezing)
3797 goto out_unlock; 3690 goto out_unlock;
3798 3691
3799 for_each_gcwq_cpu(cpu) { 3692 for_each_wq_cpu(cpu) {
3800 struct global_cwq *gcwq = get_gcwq(cpu);
3801 struct worker_pool *pool; 3693 struct worker_pool *pool;
3802 struct workqueue_struct *wq; 3694 struct workqueue_struct *wq;
3803 3695
3804 spin_lock_irq(&gcwq->lock); 3696 for_each_std_worker_pool(pool, cpu) {
3697 spin_lock_irq(&pool->lock);
3805 3698
3806 BUG_ON(!(gcwq->flags & GCWQ_FREEZING)); 3699 WARN_ON_ONCE(!(pool->flags & POOL_FREEZING));
3807 gcwq->flags &= ~GCWQ_FREEZING; 3700 pool->flags &= ~POOL_FREEZING;
3808 3701
3809 list_for_each_entry(wq, &workqueues, list) { 3702 list_for_each_entry(wq, &workqueues, list) {
3810 struct cpu_workqueue_struct *cwq = get_cwq(cpu, wq); 3703 struct pool_workqueue *pwq = get_pwq(cpu, wq);
3811 3704
3812 if (!cwq || !(wq->flags & WQ_FREEZABLE)) 3705 if (!pwq || pwq->pool != pool ||
3813 continue; 3706 !(wq->flags & WQ_FREEZABLE))
3707 continue;
3814 3708
3815 /* restore max_active and repopulate worklist */ 3709 /* restore max_active and repopulate worklist */
3816 cwq_set_max_active(cwq, wq->saved_max_active); 3710 pwq_set_max_active(pwq, wq->saved_max_active);
3817 } 3711 }
3818 3712
3819 for_each_worker_pool(pool, gcwq)
3820 wake_up_worker(pool); 3713 wake_up_worker(pool);
3821 3714
3822 spin_unlock_irq(&gcwq->lock); 3715 spin_unlock_irq(&pool->lock);
3716 }
3823 } 3717 }
3824 3718
3825 workqueue_freezing = false; 3719 workqueue_freezing = false;
@@ -3831,60 +3725,56 @@ out_unlock:
3831static int __init init_workqueues(void) 3725static int __init init_workqueues(void)
3832{ 3726{
3833 unsigned int cpu; 3727 unsigned int cpu;
3834 int i;
3835 3728
3836 /* make sure we have enough bits for OFFQ CPU number */ 3729 /* make sure we have enough bits for OFFQ pool ID */
3837 BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_CPU_SHIFT)) < 3730 BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT)) <
3838 WORK_CPU_LAST); 3731 WORK_CPU_END * NR_STD_WORKER_POOLS);
3839 3732
3840 cpu_notifier(workqueue_cpu_up_callback, CPU_PRI_WORKQUEUE_UP); 3733 cpu_notifier(workqueue_cpu_up_callback, CPU_PRI_WORKQUEUE_UP);
3841 hotcpu_notifier(workqueue_cpu_down_callback, CPU_PRI_WORKQUEUE_DOWN); 3734 hotcpu_notifier(workqueue_cpu_down_callback, CPU_PRI_WORKQUEUE_DOWN);
3842 3735
3843 /* initialize gcwqs */ 3736 /* initialize CPU pools */
3844 for_each_gcwq_cpu(cpu) { 3737 for_each_wq_cpu(cpu) {
3845 struct global_cwq *gcwq = get_gcwq(cpu);
3846 struct worker_pool *pool; 3738 struct worker_pool *pool;
3847 3739
3848 spin_lock_init(&gcwq->lock); 3740 for_each_std_worker_pool(pool, cpu) {
3849 gcwq->cpu = cpu; 3741 spin_lock_init(&pool->lock);
3850 gcwq->flags |= GCWQ_DISASSOCIATED; 3742 pool->cpu = cpu;
3851 3743 pool->flags |= POOL_DISASSOCIATED;
3852 for (i = 0; i < BUSY_WORKER_HASH_SIZE; i++)
3853 INIT_HLIST_HEAD(&gcwq->busy_hash[i]);
3854
3855 for_each_worker_pool(pool, gcwq) {
3856 pool->gcwq = gcwq;
3857 INIT_LIST_HEAD(&pool->worklist); 3744 INIT_LIST_HEAD(&pool->worklist);
3858 INIT_LIST_HEAD(&pool->idle_list); 3745 INIT_LIST_HEAD(&pool->idle_list);
3746 hash_init(pool->busy_hash);
3859 3747
3860 init_timer_deferrable(&pool->idle_timer); 3748 init_timer_deferrable(&pool->idle_timer);
3861 pool->idle_timer.function = idle_worker_timeout; 3749 pool->idle_timer.function = idle_worker_timeout;
3862 pool->idle_timer.data = (unsigned long)pool; 3750 pool->idle_timer.data = (unsigned long)pool;
3863 3751
3864 setup_timer(&pool->mayday_timer, gcwq_mayday_timeout, 3752 setup_timer(&pool->mayday_timer, pool_mayday_timeout,
3865 (unsigned long)pool); 3753 (unsigned long)pool);
3866 3754
3867 mutex_init(&pool->assoc_mutex); 3755 mutex_init(&pool->assoc_mutex);
3868 ida_init(&pool->worker_ida); 3756 ida_init(&pool->worker_ida);
3757
3758 /* alloc pool ID */
3759 BUG_ON(worker_pool_assign_id(pool));
3869 } 3760 }
3870 } 3761 }
3871 3762
3872 /* create the initial worker */ 3763 /* create the initial worker */
3873 for_each_online_gcwq_cpu(cpu) { 3764 for_each_online_wq_cpu(cpu) {
3874 struct global_cwq *gcwq = get_gcwq(cpu);
3875 struct worker_pool *pool; 3765 struct worker_pool *pool;
3876 3766
3877 if (cpu != WORK_CPU_UNBOUND) 3767 for_each_std_worker_pool(pool, cpu) {
3878 gcwq->flags &= ~GCWQ_DISASSOCIATED;
3879
3880 for_each_worker_pool(pool, gcwq) {
3881 struct worker *worker; 3768 struct worker *worker;
3882 3769
3770 if (cpu != WORK_CPU_UNBOUND)
3771 pool->flags &= ~POOL_DISASSOCIATED;
3772
3883 worker = create_worker(pool); 3773 worker = create_worker(pool);
3884 BUG_ON(!worker); 3774 BUG_ON(!worker);
3885 spin_lock_irq(&gcwq->lock); 3775 spin_lock_irq(&pool->lock);
3886 start_worker(worker); 3776 start_worker(worker);
3887 spin_unlock_irq(&gcwq->lock); 3777 spin_unlock_irq(&pool->lock);
3888 } 3778 }
3889 } 3779 }
3890 3780
diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
new file mode 100644
index 000000000000..07650264ec15
--- /dev/null
+++ b/kernel/workqueue_internal.h
@@ -0,0 +1,65 @@
1/*
2 * kernel/workqueue_internal.h
3 *
4 * Workqueue internal header file. Only to be included by workqueue and
5 * core kernel subsystems.
6 */
7#ifndef _KERNEL_WORKQUEUE_INTERNAL_H
8#define _KERNEL_WORKQUEUE_INTERNAL_H
9
10#include <linux/workqueue.h>
11#include <linux/kthread.h>
12
13struct worker_pool;
14
15/*
16 * The poor guys doing the actual heavy lifting. All on-duty workers are
17 * either serving the manager role, on idle list or on busy hash. For
18 * details on the locking annotation (L, I, X...), refer to workqueue.c.
19 *
20 * Only to be used in workqueue and async.
21 */
22struct worker {
23 /* on idle list while idle, on busy hash table while busy */
24 union {
25 struct list_head entry; /* L: while idle */
26 struct hlist_node hentry; /* L: while busy */
27 };
28
29 struct work_struct *current_work; /* L: work being processed */
30 work_func_t current_func; /* L: current_work's fn */
31 struct pool_workqueue *current_pwq; /* L: current_work's pwq */
32 struct list_head scheduled; /* L: scheduled works */
33 struct task_struct *task; /* I: worker task */
34 struct worker_pool *pool; /* I: the associated pool */
35 /* 64 bytes boundary on 64bit, 32 on 32bit */
36 unsigned long last_active; /* L: last active timestamp */
37 unsigned int flags; /* X: flags */
38 int id; /* I: worker id */
39
40 /* for rebinding worker to CPU */
41 struct work_struct rebind_work; /* L: for busy worker */
42
43 /* used only by rescuers to point to the target workqueue */
44 struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */
45};
46
47/**
48 * current_wq_worker - return struct worker if %current is a workqueue worker
49 */
50static inline struct worker *current_wq_worker(void)
51{
52 if (current->flags & PF_WQ_WORKER)
53 return kthread_data(current);
54 return NULL;
55}
56
57/*
58 * Scheduler hooks for concurrency managed workqueue. Only to be used from
59 * sched.c and workqueue.c.
60 */
61void wq_worker_waking_up(struct task_struct *task, unsigned int cpu);
62struct task_struct *wq_worker_sleeping(struct task_struct *task,
63 unsigned int cpu);
64
65#endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
diff --git a/kernel/workqueue_sched.h b/kernel/workqueue_sched.h
deleted file mode 100644
index 2d10fc98dc79..000000000000
--- a/kernel/workqueue_sched.h
+++ /dev/null
@@ -1,9 +0,0 @@
1/*
2 * kernel/workqueue_sched.h
3 *
4 * Scheduler hooks for concurrency managed workqueue. Only to be
5 * included from sched.c and workqueue.c.
6 */
7void wq_worker_waking_up(struct task_struct *task, unsigned int cpu);
8struct task_struct *wq_worker_sleeping(struct task_struct *task,
9 unsigned int cpu);
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-01 16:53:05 -0400