11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * workqueue.h --- work queue handling for Linux. 31da177e4SLinus Torvalds */ 41da177e4SLinus Torvalds 51da177e4SLinus Torvalds #ifndef _LINUX_WORKQUEUE_H 61da177e4SLinus Torvalds #define _LINUX_WORKQUEUE_H 71da177e4SLinus Torvalds 81da177e4SLinus Torvalds #include <linux/timer.h> 91da177e4SLinus Torvalds #include <linux/linkage.h> 101da177e4SLinus Torvalds #include <linux/bitops.h> 114e6045f1SJohannes Berg #include <linux/lockdep.h> 127a22ad75STejun Heo #include <linux/threads.h> 1360063497SArun Sharma #include <linux/atomic.h> 147a4e344cSTejun Heo #include <linux/cpumask.h> 151da177e4SLinus Torvalds 161da177e4SLinus Torvalds struct workqueue_struct; 171da177e4SLinus Torvalds 1865f27f38SDavid Howells struct work_struct; 1965f27f38SDavid Howells typedef void (*work_func_t)(struct work_struct *work); 20d8e794dfSTejun Heo void delayed_work_timer_fn(unsigned long __data); 216bb49e59SDavid Howells 22a08727baSLinus Torvalds /* 23a08727baSLinus Torvalds * The first word is the work queue pointer and the flags rolled into 24a08727baSLinus Torvalds * one 25a08727baSLinus Torvalds */ 26a08727baSLinus Torvalds #define work_data_bits(work) ((unsigned long *)(&(work)->data)) 27a08727baSLinus Torvalds 2822df02bbSTejun Heo enum { 2922df02bbSTejun Heo WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */ 308a2e8e5dSTejun Heo WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */ 31112202d9STejun Heo WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */ 328a2e8e5dSTejun Heo WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */ 3322df02bbSTejun Heo #ifdef CONFIG_DEBUG_OBJECTS_WORK 348a2e8e5dSTejun Heo WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */ 358a2e8e5dSTejun Heo WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */ 360f900049STejun Heo #else 378a2e8e5dSTejun Heo WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */ 3822df02bbSTejun Heo #endif 3922df02bbSTejun Heo 4073f53c4aSTejun Heo WORK_STRUCT_COLOR_BITS = 4, 4173f53c4aSTejun Heo 4222df02bbSTejun Heo WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT, 438a2e8e5dSTejun Heo WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT, 44112202d9STejun Heo WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT, 45affee4b2STejun Heo WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT, 4622df02bbSTejun Heo #ifdef CONFIG_DEBUG_OBJECTS_WORK 4722df02bbSTejun Heo WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT, 4822df02bbSTejun Heo #else 4922df02bbSTejun Heo WORK_STRUCT_STATIC = 0, 5022df02bbSTejun Heo #endif 5122df02bbSTejun Heo 5273f53c4aSTejun Heo /* 5373f53c4aSTejun Heo * The last color is no color used for works which don't 5473f53c4aSTejun Heo * participate in workqueue flushing. 5573f53c4aSTejun Heo */ 5673f53c4aSTejun Heo WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1, 5773f53c4aSTejun Heo WORK_NO_COLOR = WORK_NR_COLORS, 5873f53c4aSTejun Heo 59bdbc5dd7STejun Heo /* special cpu IDs */ 60f3421797STejun Heo WORK_CPU_UNBOUND = NR_CPUS, 616be19588SLai Jiangshan WORK_CPU_END = NR_CPUS + 1, 62bdbc5dd7STejun Heo 6373f53c4aSTejun Heo /* 64112202d9STejun Heo * Reserve 7 bits off of pwq pointer w/ debugobjects turned off. 65112202d9STejun Heo * This makes pwqs aligned to 256 bytes and allows 15 workqueue 66112202d9STejun Heo * flush colors. 6773f53c4aSTejun Heo */ 6873f53c4aSTejun Heo WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT + 6973f53c4aSTejun Heo WORK_STRUCT_COLOR_BITS, 7073f53c4aSTejun Heo 71112202d9STejun Heo /* data contains off-queue information when !WORK_STRUCT_PWQ */ 7245d9550aSLai Jiangshan WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT, 73bbb68dfaSTejun Heo 74bbb68dfaSTejun Heo WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE), 75bbb68dfaSTejun Heo 76715b06b8STejun Heo /* 77715b06b8STejun Heo * When a work item is off queue, its high bits point to the last 787c3eed5cSTejun Heo * pool it was on. Cap at 31 bits and use the highest number to 797c3eed5cSTejun Heo * indicate that no pool is associated. 80715b06b8STejun Heo */ 81bbb68dfaSTejun Heo WORK_OFFQ_FLAG_BITS = 1, 827c3eed5cSTejun Heo WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS, 837c3eed5cSTejun Heo WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT, 847c3eed5cSTejun Heo WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31, 857c3eed5cSTejun Heo WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1, 86b5490077STejun Heo 87b5490077STejun Heo /* convenience constants */ 880f900049STejun Heo WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1, 8922df02bbSTejun Heo WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK, 907c3eed5cSTejun Heo WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT, 91dcd989cbSTejun Heo 92dcd989cbSTejun Heo /* bit mask for work_busy() return values */ 93dcd989cbSTejun Heo WORK_BUSY_PENDING = 1 << 0, 94dcd989cbSTejun Heo WORK_BUSY_RUNNING = 1 << 1, 953d1cb205STejun Heo 963d1cb205STejun Heo /* maximum string length for set_worker_desc() */ 973d1cb205STejun Heo WORKER_DESC_LEN = 24, 9822df02bbSTejun Heo }; 9922df02bbSTejun Heo 1001da177e4SLinus Torvalds struct work_struct { 101a08727baSLinus Torvalds atomic_long_t data; 1021da177e4SLinus Torvalds struct list_head entry; 1036bb49e59SDavid Howells work_func_t func; 1044e6045f1SJohannes Berg #ifdef CONFIG_LOCKDEP 1054e6045f1SJohannes Berg struct lockdep_map lockdep_map; 1064e6045f1SJohannes Berg #endif 10752bad64dSDavid Howells }; 10852bad64dSDavid Howells 1097c3eed5cSTejun Heo #define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL) 1107a22ad75STejun Heo #define WORK_DATA_STATIC_INIT() \ 1117c3eed5cSTejun Heo ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC) 112a08727baSLinus Torvalds 11352bad64dSDavid Howells struct delayed_work { 11452bad64dSDavid Howells struct work_struct work; 1151da177e4SLinus Torvalds struct timer_list timer; 11660c057bcSLai Jiangshan 11760c057bcSLai Jiangshan /* target workqueue and CPU ->timer uses to queue ->work */ 11860c057bcSLai Jiangshan struct workqueue_struct *wq; 1191265057fSTejun Heo int cpu; 1201da177e4SLinus Torvalds }; 1211da177e4SLinus Torvalds 1227a4e344cSTejun Heo /* 1237a4e344cSTejun Heo * A struct for workqueue attributes. This can be used to change 1247a4e344cSTejun Heo * attributes of an unbound workqueue. 125d55262c4STejun Heo * 126d55262c4STejun Heo * Unlike other fields, ->no_numa isn't a property of a worker_pool. It 127d55262c4STejun Heo * only modifies how apply_workqueue_attrs() select pools and thus doesn't 128d55262c4STejun Heo * participate in pool hash calculations or equality comparisons. 1297a4e344cSTejun Heo */ 1307a4e344cSTejun Heo struct workqueue_attrs { 1317a4e344cSTejun Heo int nice; /* nice level */ 1327a4e344cSTejun Heo cpumask_var_t cpumask; /* allowed CPUs */ 133d55262c4STejun Heo bool no_numa; /* disable NUMA affinity */ 1347a4e344cSTejun Heo }; 1357a4e344cSTejun Heo 136bf6aede7SJean Delvare static inline struct delayed_work *to_delayed_work(struct work_struct *work) 137bf6aede7SJean Delvare { 138bf6aede7SJean Delvare return container_of(work, struct delayed_work, work); 139bf6aede7SJean Delvare } 140bf6aede7SJean Delvare 1411fa44ecaSJames Bottomley struct execute_work { 1421fa44ecaSJames Bottomley struct work_struct work; 1431fa44ecaSJames Bottomley }; 1441fa44ecaSJames Bottomley 1454e6045f1SJohannes Berg #ifdef CONFIG_LOCKDEP 1464e6045f1SJohannes Berg /* 1474e6045f1SJohannes Berg * NB: because we have to copy the lockdep_map, setting _key 1484e6045f1SJohannes Berg * here is required, otherwise it could get initialised to the 1494e6045f1SJohannes Berg * copy of the lockdep_map! 1504e6045f1SJohannes Berg */ 1514e6045f1SJohannes Berg #define __WORK_INIT_LOCKDEP_MAP(n, k) \ 1524e6045f1SJohannes Berg .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k), 1534e6045f1SJohannes Berg #else 1544e6045f1SJohannes Berg #define __WORK_INIT_LOCKDEP_MAP(n, k) 1554e6045f1SJohannes Berg #endif 1564e6045f1SJohannes Berg 15765f27f38SDavid Howells #define __WORK_INITIALIZER(n, f) { \ 158dc186ad7SThomas Gleixner .data = WORK_DATA_STATIC_INIT(), \ 15965f27f38SDavid Howells .entry = { &(n).entry, &(n).entry }, \ 16065f27f38SDavid Howells .func = (f), \ 1614e6045f1SJohannes Berg __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \ 16265f27f38SDavid Howells } 16365f27f38SDavid Howells 164f991b318STejun Heo #define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \ 16565f27f38SDavid Howells .work = __WORK_INITIALIZER((n).work, (f)), \ 166f991b318STejun Heo .timer = __TIMER_INITIALIZER(delayed_work_timer_fn, \ 167e0aecdd8STejun Heo 0, (unsigned long)&(n), \ 168e0aecdd8STejun Heo (tflags) | TIMER_IRQSAFE), \ 169dd6414b5SPhil Carmody } 170dd6414b5SPhil Carmody 17165f27f38SDavid Howells #define DECLARE_WORK(n, f) \ 17265f27f38SDavid Howells struct work_struct n = __WORK_INITIALIZER(n, f) 17365f27f38SDavid Howells 17465f27f38SDavid Howells #define DECLARE_DELAYED_WORK(n, f) \ 175f991b318STejun Heo struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0) 17665f27f38SDavid Howells 177203b42f7STejun Heo #define DECLARE_DEFERRABLE_WORK(n, f) \ 178f991b318STejun Heo struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE) 179dd6414b5SPhil Carmody 180dc186ad7SThomas Gleixner #ifdef CONFIG_DEBUG_OBJECTS_WORK 181dc186ad7SThomas Gleixner extern void __init_work(struct work_struct *work, int onstack); 182dc186ad7SThomas Gleixner extern void destroy_work_on_stack(struct work_struct *work); 1834690c4abSTejun Heo static inline unsigned int work_static(struct work_struct *work) 1844690c4abSTejun Heo { 18522df02bbSTejun Heo return *work_data_bits(work) & WORK_STRUCT_STATIC; 1864690c4abSTejun Heo } 187dc186ad7SThomas Gleixner #else 188dc186ad7SThomas Gleixner static inline void __init_work(struct work_struct *work, int onstack) { } 189dc186ad7SThomas Gleixner static inline void destroy_work_on_stack(struct work_struct *work) { } 1904690c4abSTejun Heo static inline unsigned int work_static(struct work_struct *work) { return 0; } 191dc186ad7SThomas Gleixner #endif 192dc186ad7SThomas Gleixner 1931da177e4SLinus Torvalds /* 19452bad64dSDavid Howells * initialize all of a work item in one go 195a08727baSLinus Torvalds * 196b9049df5SDmitri Vorobiev * NOTE! No point in using "atomic_long_set()": using a direct 197a08727baSLinus Torvalds * assignment of the work data initializer allows the compiler 198a08727baSLinus Torvalds * to generate better code. 1991da177e4SLinus Torvalds */ 2004e6045f1SJohannes Berg #ifdef CONFIG_LOCKDEP 201dc186ad7SThomas Gleixner #define __INIT_WORK(_work, _func, _onstack) \ 2024e6045f1SJohannes Berg do { \ 2034e6045f1SJohannes Berg static struct lock_class_key __key; \ 2044e6045f1SJohannes Berg \ 205dc186ad7SThomas Gleixner __init_work((_work), _onstack); \ 2064e6045f1SJohannes Berg (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ 2074e6045f1SJohannes Berg lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0); \ 2084e6045f1SJohannes Berg INIT_LIST_HEAD(&(_work)->entry); \ 209f073f922STejun Heo (_work)->func = (_func); \ 2104e6045f1SJohannes Berg } while (0) 2114e6045f1SJohannes Berg #else 212dc186ad7SThomas Gleixner #define __INIT_WORK(_work, _func, _onstack) \ 2131da177e4SLinus Torvalds do { \ 214dc186ad7SThomas Gleixner __init_work((_work), _onstack); \ 21523b2e599SOleg Nesterov (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ 21665f27f38SDavid Howells INIT_LIST_HEAD(&(_work)->entry); \ 217f073f922STejun Heo (_work)->func = (_func); \ 21865f27f38SDavid Howells } while (0) 2194e6045f1SJohannes Berg #endif 22065f27f38SDavid Howells 221dc186ad7SThomas Gleixner #define INIT_WORK(_work, _func) \ 222dc186ad7SThomas Gleixner do { \ 223dc186ad7SThomas Gleixner __INIT_WORK((_work), (_func), 0); \ 224dc186ad7SThomas Gleixner } while (0) 225dc186ad7SThomas Gleixner 226ca1cab37SAndrew Morton #define INIT_WORK_ONSTACK(_work, _func) \ 227dc186ad7SThomas Gleixner do { \ 228dc186ad7SThomas Gleixner __INIT_WORK((_work), (_func), 1); \ 229dc186ad7SThomas Gleixner } while (0) 230dc186ad7SThomas Gleixner 231f991b318STejun Heo #define __INIT_DELAYED_WORK(_work, _func, _tflags) \ 23265f27f38SDavid Howells do { \ 23365f27f38SDavid Howells INIT_WORK(&(_work)->work, (_func)); \ 234f991b318STejun Heo __setup_timer(&(_work)->timer, delayed_work_timer_fn, \ 235e0aecdd8STejun Heo (unsigned long)(_work), \ 236e0aecdd8STejun Heo (_tflags) | TIMER_IRQSAFE); \ 23765f27f38SDavid Howells } while (0) 23865f27f38SDavid Howells 239f991b318STejun Heo #define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags) \ 2406d612b0fSPeter Zijlstra do { \ 241ca1cab37SAndrew Morton INIT_WORK_ONSTACK(&(_work)->work, (_func)); \ 242f991b318STejun Heo __setup_timer_on_stack(&(_work)->timer, \ 243f991b318STejun Heo delayed_work_timer_fn, \ 244f991b318STejun Heo (unsigned long)(_work), \ 245e0aecdd8STejun Heo (_tflags) | TIMER_IRQSAFE); \ 2466d612b0fSPeter Zijlstra } while (0) 2476d612b0fSPeter Zijlstra 248f991b318STejun Heo #define INIT_DELAYED_WORK(_work, _func) \ 249f991b318STejun Heo __INIT_DELAYED_WORK(_work, _func, 0) 250f991b318STejun Heo 251f991b318STejun Heo #define INIT_DELAYED_WORK_ONSTACK(_work, _func) \ 252f991b318STejun Heo __INIT_DELAYED_WORK_ONSTACK(_work, _func, 0) 253f991b318STejun Heo 254203b42f7STejun Heo #define INIT_DEFERRABLE_WORK(_work, _func) \ 255f991b318STejun Heo __INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE) 256f991b318STejun Heo 257f991b318STejun Heo #define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func) \ 258f991b318STejun Heo __INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE) 25928287033SVenki Pallipadi 260365970a1SDavid Howells /** 261365970a1SDavid Howells * work_pending - Find out whether a work item is currently pending 262365970a1SDavid Howells * @work: The work item in question 263365970a1SDavid Howells */ 264365970a1SDavid Howells #define work_pending(work) \ 26522df02bbSTejun Heo test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)) 266365970a1SDavid Howells 267365970a1SDavid Howells /** 268365970a1SDavid Howells * delayed_work_pending - Find out whether a delayable work item is currently 269365970a1SDavid Howells * pending 270365970a1SDavid Howells * @work: The work item in question 271365970a1SDavid Howells */ 2720221872aSLinus Torvalds #define delayed_work_pending(w) \ 2730221872aSLinus Torvalds work_pending(&(w)->work) 274365970a1SDavid Howells 27565f27f38SDavid Howells /** 27623b2e599SOleg Nesterov * work_clear_pending - for internal use only, mark a work item as not pending 27723b2e599SOleg Nesterov * @work: The work item in question 27865f27f38SDavid Howells */ 27923b2e599SOleg Nesterov #define work_clear_pending(work) \ 28022df02bbSTejun Heo clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)) 28165f27f38SDavid Howells 282c54fce6eSTejun Heo /* 283c54fce6eSTejun Heo * Workqueue flags and constants. For details, please refer to 284c54fce6eSTejun Heo * Documentation/workqueue.txt. 285c54fce6eSTejun Heo */ 28697e37d7bSTejun Heo enum { 28712076373STejun Heo /* 28812076373STejun Heo * All wqs are now non-reentrant making the following flag 28912076373STejun Heo * meaningless. Will be removed. 29012076373STejun Heo */ 29112076373STejun Heo WQ_NON_REENTRANT = 1 << 0, /* DEPRECATED */ 29212076373STejun Heo 293c7fc77f7STejun Heo WQ_UNBOUND = 1 << 1, /* not bound to any cpu */ 29458a69cb4STejun Heo WQ_FREEZABLE = 1 << 2, /* freeze during suspend */ 2956370a6adSTejun Heo WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */ 296649027d7STejun Heo WQ_HIGHPRI = 1 << 4, /* high priority */ 297fb0e7bebSTejun Heo WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */ 298226223abSTejun Heo WQ_SYSFS = 1 << 6, /* visible in sysfs, see wq_sysfs_register() */ 299b71ab8c2STejun Heo 300cee22a15SViresh Kumar /* 301cee22a15SViresh Kumar * Per-cpu workqueues are generally preferred because they tend to 302cee22a15SViresh Kumar * show better performance thanks to cache locality. Per-cpu 303cee22a15SViresh Kumar * workqueues exclude the scheduler from choosing the CPU to 304cee22a15SViresh Kumar * execute the worker threads, which has an unfortunate side effect 305cee22a15SViresh Kumar * of increasing power consumption. 306cee22a15SViresh Kumar * 307cee22a15SViresh Kumar * The scheduler considers a CPU idle if it doesn't have any task 308cee22a15SViresh Kumar * to execute and tries to keep idle cores idle to conserve power; 309cee22a15SViresh Kumar * however, for example, a per-cpu work item scheduled from an 310cee22a15SViresh Kumar * interrupt handler on an idle CPU will force the scheduler to 311cee22a15SViresh Kumar * excute the work item on that CPU breaking the idleness, which in 312cee22a15SViresh Kumar * turn may lead to more scheduling choices which are sub-optimal 313cee22a15SViresh Kumar * in terms of power consumption. 314cee22a15SViresh Kumar * 315cee22a15SViresh Kumar * Workqueues marked with WQ_POWER_EFFICIENT are per-cpu by default 316cee22a15SViresh Kumar * but become unbound if workqueue.power_efficient kernel param is 317cee22a15SViresh Kumar * specified. Per-cpu workqueues which are identified to 318cee22a15SViresh Kumar * contribute significantly to power-consumption are identified and 319cee22a15SViresh Kumar * marked with this flag and enabling the power_efficient mode 320cee22a15SViresh Kumar * leads to noticeable power saving at the cost of small 321cee22a15SViresh Kumar * performance disadvantage. 322cee22a15SViresh Kumar * 323cee22a15SViresh Kumar * http://thread.gmane.org/gmane.linux.kernel/1480396 324cee22a15SViresh Kumar */ 325cee22a15SViresh Kumar WQ_POWER_EFFICIENT = 1 << 7, 326cee22a15SViresh Kumar 327618b01ebSTejun Heo __WQ_DRAINING = 1 << 16, /* internal: workqueue is draining */ 3288719dceaSTejun Heo __WQ_ORDERED = 1 << 17, /* internal: workqueue is ordered */ 329e41e704bSTejun Heo 330b71ab8c2STejun Heo WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */ 331f3421797STejun Heo WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */ 332b71ab8c2STejun Heo WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2, 33397e37d7bSTejun Heo }; 33452bad64dSDavid Howells 335f3421797STejun Heo /* unbound wq's aren't per-cpu, scale max_active according to #cpus */ 336f3421797STejun Heo #define WQ_UNBOUND_MAX_ACTIVE \ 337f3421797STejun Heo max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU) 338f3421797STejun Heo 339d320c038STejun Heo /* 340d320c038STejun Heo * System-wide workqueues which are always present. 341d320c038STejun Heo * 342d320c038STejun Heo * system_wq is the one used by schedule[_delayed]_work[_on](). 343d320c038STejun Heo * Multi-CPU multi-threaded. There are users which expect relatively 344d320c038STejun Heo * short queue flush time. Don't queue works which can run for too 345d320c038STejun Heo * long. 346d320c038STejun Heo * 347d320c038STejun Heo * system_long_wq is similar to system_wq but may host long running 348d320c038STejun Heo * works. Queue flushing might take relatively long. 349d320c038STejun Heo * 350f3421797STejun Heo * system_unbound_wq is unbound workqueue. Workers are not bound to 351f3421797STejun Heo * any specific CPU, not concurrency managed, and all queued works are 352f3421797STejun Heo * executed immediately as long as max_active limit is not reached and 353f3421797STejun Heo * resources are available. 3544149efb2STejun Heo * 35524d51addSTejun Heo * system_freezable_wq is equivalent to system_wq except that it's 35624d51addSTejun Heo * freezable. 3570668106cSViresh Kumar * 3580668106cSViresh Kumar * *_power_efficient_wq are inclined towards saving power and converted 3590668106cSViresh Kumar * into WQ_UNBOUND variants if 'wq_power_efficient' is enabled; otherwise, 3600668106cSViresh Kumar * they are same as their non-power-efficient counterparts - e.g. 3610668106cSViresh Kumar * system_power_efficient_wq is identical to system_wq if 3620668106cSViresh Kumar * 'wq_power_efficient' is disabled. See WQ_POWER_EFFICIENT for more info. 363d320c038STejun Heo */ 364d320c038STejun Heo extern struct workqueue_struct *system_wq; 365d320c038STejun Heo extern struct workqueue_struct *system_long_wq; 366f3421797STejun Heo extern struct workqueue_struct *system_unbound_wq; 36724d51addSTejun Heo extern struct workqueue_struct *system_freezable_wq; 3680668106cSViresh Kumar extern struct workqueue_struct *system_power_efficient_wq; 3690668106cSViresh Kumar extern struct workqueue_struct *system_freezable_power_efficient_wq; 370ae930e0fSTejun Heo 3713b07e9caSTejun Heo static inline struct workqueue_struct * __deprecated __system_nrt_wq(void) 372ae930e0fSTejun Heo { 373ae930e0fSTejun Heo return system_wq; 374ae930e0fSTejun Heo } 375ae930e0fSTejun Heo 3763b07e9caSTejun Heo static inline struct workqueue_struct * __deprecated __system_nrt_freezable_wq(void) 377ae930e0fSTejun Heo { 378ae930e0fSTejun Heo return system_freezable_wq; 379ae930e0fSTejun Heo } 380ae930e0fSTejun Heo 381ae930e0fSTejun Heo /* equivlalent to system_wq and system_freezable_wq, deprecated */ 382ae930e0fSTejun Heo #define system_nrt_wq __system_nrt_wq() 383ae930e0fSTejun Heo #define system_nrt_freezable_wq __system_nrt_freezable_wq() 3841da177e4SLinus Torvalds 3854e6045f1SJohannes Berg extern struct workqueue_struct * 386b196be89STejun Heo __alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, 387b196be89STejun Heo struct lock_class_key *key, const char *lock_name, ...) __printf(1, 6); 3884e6045f1SJohannes Berg 389b196be89STejun Heo /** 390b196be89STejun Heo * alloc_workqueue - allocate a workqueue 391b196be89STejun Heo * @fmt: printf format for the name of the workqueue 392b196be89STejun Heo * @flags: WQ_* flags 393b196be89STejun Heo * @max_active: max in-flight work items, 0 for default 394b196be89STejun Heo * @args: args for @fmt 395b196be89STejun Heo * 396b196be89STejun Heo * Allocate a workqueue with the specified parameters. For detailed 397b196be89STejun Heo * information on WQ_* flags, please refer to Documentation/workqueue.txt. 398b196be89STejun Heo * 399b196be89STejun Heo * The __lock_name macro dance is to guarantee that single lock_class_key 400b196be89STejun Heo * doesn't end up with different namesm, which isn't allowed by lockdep. 401b196be89STejun Heo * 402b196be89STejun Heo * RETURNS: 403b196be89STejun Heo * Pointer to the allocated workqueue on success, %NULL on failure. 404b196be89STejun Heo */ 4054e6045f1SJohannes Berg #ifdef CONFIG_LOCKDEP 406b196be89STejun Heo #define alloc_workqueue(fmt, flags, max_active, args...) \ 4074e6045f1SJohannes Berg ({ \ 4084e6045f1SJohannes Berg static struct lock_class_key __key; \ 409eb13ba87SJohannes Berg const char *__lock_name; \ 410eb13ba87SJohannes Berg \ 411fada94eeSLi Zhong __lock_name = #fmt#args; \ 4124e6045f1SJohannes Berg \ 413b196be89STejun Heo __alloc_workqueue_key((fmt), (flags), (max_active), \ 414b196be89STejun Heo &__key, __lock_name, ##args); \ 4154e6045f1SJohannes Berg }) 4164e6045f1SJohannes Berg #else 417b196be89STejun Heo #define alloc_workqueue(fmt, flags, max_active, args...) \ 418b196be89STejun Heo __alloc_workqueue_key((fmt), (flags), (max_active), \ 419b196be89STejun Heo NULL, NULL, ##args) 4204e6045f1SJohannes Berg #endif 4214e6045f1SJohannes Berg 42281dcaf65STejun Heo /** 42381dcaf65STejun Heo * alloc_ordered_workqueue - allocate an ordered workqueue 424b196be89STejun Heo * @fmt: printf format for the name of the workqueue 42558a69cb4STejun Heo * @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful) 426b196be89STejun Heo * @args: args for @fmt 42781dcaf65STejun Heo * 42881dcaf65STejun Heo * Allocate an ordered workqueue. An ordered workqueue executes at 42981dcaf65STejun Heo * most one work item at any given time in the queued order. They are 43081dcaf65STejun Heo * implemented as unbound workqueues with @max_active of one. 43181dcaf65STejun Heo * 43281dcaf65STejun Heo * RETURNS: 43381dcaf65STejun Heo * Pointer to the allocated workqueue on success, %NULL on failure. 43481dcaf65STejun Heo */ 435b196be89STejun Heo #define alloc_ordered_workqueue(fmt, flags, args...) \ 4368719dceaSTejun Heo alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | (flags), 1, ##args) 43781dcaf65STejun Heo 43897e37d7bSTejun Heo #define create_workqueue(name) \ 439d8537548SKees Cook alloc_workqueue("%s", WQ_MEM_RECLAIM, 1, (name)) 44058a69cb4STejun Heo #define create_freezable_workqueue(name) \ 441d8537548SKees Cook alloc_workqueue("%s", WQ_FREEZABLE | WQ_UNBOUND | WQ_MEM_RECLAIM, \ 442d8537548SKees Cook 1, (name)) 44397e37d7bSTejun Heo #define create_singlethread_workqueue(name) \ 444d8537548SKees Cook alloc_workqueue("%s", WQ_UNBOUND | WQ_MEM_RECLAIM, 1, (name)) 4451da177e4SLinus Torvalds 4461da177e4SLinus Torvalds extern void destroy_workqueue(struct workqueue_struct *wq); 4471da177e4SLinus Torvalds 4487a4e344cSTejun Heo struct workqueue_attrs *alloc_workqueue_attrs(gfp_t gfp_mask); 4497a4e344cSTejun Heo void free_workqueue_attrs(struct workqueue_attrs *attrs); 4509e8cd2f5STejun Heo int apply_workqueue_attrs(struct workqueue_struct *wq, 4519e8cd2f5STejun Heo const struct workqueue_attrs *attrs); 4527a4e344cSTejun Heo 453d4283e93STejun Heo extern bool queue_work_on(int cpu, struct workqueue_struct *wq, 454c1a220e7SZhang Rui struct work_struct *work); 455d4283e93STejun Heo extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq, 45652bad64dSDavid Howells struct delayed_work *work, unsigned long delay); 4578376fe22STejun Heo extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq, 4588376fe22STejun Heo struct delayed_work *dwork, unsigned long delay); 45928e53bddSOleg Nesterov 460b3c97528SHarvey Harrison extern void flush_workqueue(struct workqueue_struct *wq); 4619c5a2ba7STejun Heo extern void drain_workqueue(struct workqueue_struct *wq); 46228e53bddSOleg Nesterov extern void flush_scheduled_work(void); 4631da177e4SLinus Torvalds 46465f27f38SDavid Howells extern int schedule_on_each_cpu(work_func_t func); 4651da177e4SLinus Torvalds 46665f27f38SDavid Howells int execute_in_process_context(work_func_t fn, struct execute_work *); 4671da177e4SLinus Torvalds 468401a8d04STejun Heo extern bool flush_work(struct work_struct *work); 469401a8d04STejun Heo extern bool cancel_work_sync(struct work_struct *work); 470401a8d04STejun Heo 471401a8d04STejun Heo extern bool flush_delayed_work(struct delayed_work *dwork); 47257b30ae7STejun Heo extern bool cancel_delayed_work(struct delayed_work *dwork); 473401a8d04STejun Heo extern bool cancel_delayed_work_sync(struct delayed_work *dwork); 47428e53bddSOleg Nesterov 475dcd989cbSTejun Heo extern void workqueue_set_max_active(struct workqueue_struct *wq, 476dcd989cbSTejun Heo int max_active); 477e6267616STejun Heo extern bool current_is_workqueue_rescuer(void); 478d84ff051STejun Heo extern bool workqueue_congested(int cpu, struct workqueue_struct *wq); 479dcd989cbSTejun Heo extern unsigned int work_busy(struct work_struct *work); 4803d1cb205STejun Heo extern __printf(1, 2) void set_worker_desc(const char *fmt, ...); 4813d1cb205STejun Heo extern void print_worker_info(const char *log_lvl, struct task_struct *task); 482dcd989cbSTejun Heo 4838425e3d5STejun Heo /** 4848425e3d5STejun Heo * queue_work - queue work on a workqueue 4858425e3d5STejun Heo * @wq: workqueue to use 4868425e3d5STejun Heo * @work: work to queue 4878425e3d5STejun Heo * 4888425e3d5STejun Heo * Returns %false if @work was already on a queue, %true otherwise. 4898425e3d5STejun Heo * 4908425e3d5STejun Heo * We queue the work to the CPU on which it was submitted, but if the CPU dies 4918425e3d5STejun Heo * it can be processed by another CPU. 4928425e3d5STejun Heo */ 4938425e3d5STejun Heo static inline bool queue_work(struct workqueue_struct *wq, 4948425e3d5STejun Heo struct work_struct *work) 4958425e3d5STejun Heo { 4968425e3d5STejun Heo return queue_work_on(WORK_CPU_UNBOUND, wq, work); 4978425e3d5STejun Heo } 4988425e3d5STejun Heo 4998425e3d5STejun Heo /** 5008425e3d5STejun Heo * queue_delayed_work - queue work on a workqueue after delay 5018425e3d5STejun Heo * @wq: workqueue to use 5028425e3d5STejun Heo * @dwork: delayable work to queue 5038425e3d5STejun Heo * @delay: number of jiffies to wait before queueing 5048425e3d5STejun Heo * 5058425e3d5STejun Heo * Equivalent to queue_delayed_work_on() but tries to use the local CPU. 5068425e3d5STejun Heo */ 5078425e3d5STejun Heo static inline bool queue_delayed_work(struct workqueue_struct *wq, 5088425e3d5STejun Heo struct delayed_work *dwork, 5098425e3d5STejun Heo unsigned long delay) 5108425e3d5STejun Heo { 5118425e3d5STejun Heo return queue_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay); 5128425e3d5STejun Heo } 5138425e3d5STejun Heo 5148425e3d5STejun Heo /** 5158425e3d5STejun Heo * mod_delayed_work - modify delay of or queue a delayed work 5168425e3d5STejun Heo * @wq: workqueue to use 5178425e3d5STejun Heo * @dwork: work to queue 5188425e3d5STejun Heo * @delay: number of jiffies to wait before queueing 5198425e3d5STejun Heo * 5208425e3d5STejun Heo * mod_delayed_work_on() on local CPU. 5218425e3d5STejun Heo */ 5228425e3d5STejun Heo static inline bool mod_delayed_work(struct workqueue_struct *wq, 5238425e3d5STejun Heo struct delayed_work *dwork, 5248425e3d5STejun Heo unsigned long delay) 5258425e3d5STejun Heo { 5268425e3d5STejun Heo return mod_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay); 5278425e3d5STejun Heo } 5288425e3d5STejun Heo 5298425e3d5STejun Heo /** 5308425e3d5STejun Heo * schedule_work_on - put work task on a specific cpu 5318425e3d5STejun Heo * @cpu: cpu to put the work task on 5328425e3d5STejun Heo * @work: job to be done 5338425e3d5STejun Heo * 5348425e3d5STejun Heo * This puts a job on a specific cpu 5358425e3d5STejun Heo */ 5368425e3d5STejun Heo static inline bool schedule_work_on(int cpu, struct work_struct *work) 5378425e3d5STejun Heo { 5388425e3d5STejun Heo return queue_work_on(cpu, system_wq, work); 5398425e3d5STejun Heo } 5408425e3d5STejun Heo 5418425e3d5STejun Heo /** 5428425e3d5STejun Heo * schedule_work - put work task in global workqueue 5438425e3d5STejun Heo * @work: job to be done 5448425e3d5STejun Heo * 5458425e3d5STejun Heo * Returns %false if @work was already on the kernel-global workqueue and 5468425e3d5STejun Heo * %true otherwise. 5478425e3d5STejun Heo * 5488425e3d5STejun Heo * This puts a job in the kernel-global workqueue if it was not already 5498425e3d5STejun Heo * queued and leaves it in the same position on the kernel-global 5508425e3d5STejun Heo * workqueue otherwise. 5518425e3d5STejun Heo */ 5528425e3d5STejun Heo static inline bool schedule_work(struct work_struct *work) 5538425e3d5STejun Heo { 5548425e3d5STejun Heo return queue_work(system_wq, work); 5558425e3d5STejun Heo } 5568425e3d5STejun Heo 5578425e3d5STejun Heo /** 5588425e3d5STejun Heo * schedule_delayed_work_on - queue work in global workqueue on CPU after delay 5598425e3d5STejun Heo * @cpu: cpu to use 5608425e3d5STejun Heo * @dwork: job to be done 5618425e3d5STejun Heo * @delay: number of jiffies to wait 5628425e3d5STejun Heo * 5638425e3d5STejun Heo * After waiting for a given time this puts a job in the kernel-global 5648425e3d5STejun Heo * workqueue on the specified CPU. 5658425e3d5STejun Heo */ 5668425e3d5STejun Heo static inline bool schedule_delayed_work_on(int cpu, struct delayed_work *dwork, 5678425e3d5STejun Heo unsigned long delay) 5688425e3d5STejun Heo { 5698425e3d5STejun Heo return queue_delayed_work_on(cpu, system_wq, dwork, delay); 5708425e3d5STejun Heo } 5718425e3d5STejun Heo 5728425e3d5STejun Heo /** 5738425e3d5STejun Heo * schedule_delayed_work - put work task in global workqueue after delay 5748425e3d5STejun Heo * @dwork: job to be done 5758425e3d5STejun Heo * @delay: number of jiffies to wait or 0 for immediate execution 5768425e3d5STejun Heo * 5778425e3d5STejun Heo * After waiting for a given time this puts a job in the kernel-global 5788425e3d5STejun Heo * workqueue. 5798425e3d5STejun Heo */ 5808425e3d5STejun Heo static inline bool schedule_delayed_work(struct delayed_work *dwork, 5818425e3d5STejun Heo unsigned long delay) 5828425e3d5STejun Heo { 5838425e3d5STejun Heo return queue_delayed_work(system_wq, dwork, delay); 5848425e3d5STejun Heo } 5858425e3d5STejun Heo 5868425e3d5STejun Heo /** 5878425e3d5STejun Heo * keventd_up - is workqueue initialized yet? 5888425e3d5STejun Heo */ 5898425e3d5STejun Heo static inline bool keventd_up(void) 5908425e3d5STejun Heo { 5918425e3d5STejun Heo return system_wq != NULL; 5928425e3d5STejun Heo } 5938425e3d5STejun Heo 594606a5020STejun Heo /* used to be different but now identical to flush_work(), deprecated */ 59543829731STejun Heo static inline bool __deprecated flush_work_sync(struct work_struct *work) 596606a5020STejun Heo { 597606a5020STejun Heo return flush_work(work); 598606a5020STejun Heo } 599606a5020STejun Heo 600606a5020STejun Heo /* used to be different but now identical to flush_delayed_work(), deprecated */ 60143829731STejun Heo static inline bool __deprecated flush_delayed_work_sync(struct delayed_work *dwork) 602606a5020STejun Heo { 603606a5020STejun Heo return flush_delayed_work(dwork); 604606a5020STejun Heo } 605606a5020STejun Heo 6062d3854a3SRusty Russell #ifndef CONFIG_SMP 607d84ff051STejun Heo static inline long work_on_cpu(int cpu, long (*fn)(void *), void *arg) 6082d3854a3SRusty Russell { 6092d3854a3SRusty Russell return fn(arg); 6102d3854a3SRusty Russell } 6112d3854a3SRusty Russell #else 612d84ff051STejun Heo long work_on_cpu(int cpu, long (*fn)(void *), void *arg); 6132d3854a3SRusty Russell #endif /* CONFIG_SMP */ 614a25909a4SPaul E. McKenney 615a0a1a5fdSTejun Heo #ifdef CONFIG_FREEZER 616a0a1a5fdSTejun Heo extern void freeze_workqueues_begin(void); 617a0a1a5fdSTejun Heo extern bool freeze_workqueues_busy(void); 618a0a1a5fdSTejun Heo extern void thaw_workqueues(void); 619a0a1a5fdSTejun Heo #endif /* CONFIG_FREEZER */ 620a0a1a5fdSTejun Heo 621226223abSTejun Heo #ifdef CONFIG_SYSFS 622226223abSTejun Heo int workqueue_sysfs_register(struct workqueue_struct *wq); 623226223abSTejun Heo #else /* CONFIG_SYSFS */ 624226223abSTejun Heo static inline int workqueue_sysfs_register(struct workqueue_struct *wq) 625226223abSTejun Heo { return 0; } 626226223abSTejun Heo #endif /* CONFIG_SYSFS */ 627226223abSTejun Heo 6281da177e4SLinus Torvalds #endif 629