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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /include/linux/workqueue.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/linux/workqueue.h')
-rw-r--r-- | include/linux/workqueue.h | 748 |
1 files changed, 748 insertions, 0 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h new file mode 100644 index 000000000..5d052e193 --- /dev/null +++ b/include/linux/workqueue.h @@ -0,0 +1,748 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * workqueue.h --- work queue handling for Linux. + */ + +#ifndef _LINUX_WORKQUEUE_H +#define _LINUX_WORKQUEUE_H + +#include <linux/timer.h> +#include <linux/linkage.h> +#include <linux/bitops.h> +#include <linux/lockdep.h> +#include <linux/threads.h> +#include <linux/atomic.h> +#include <linux/cpumask.h> +#include <linux/rcupdate.h> + +struct workqueue_struct; + +struct work_struct; +typedef void (*work_func_t)(struct work_struct *work); +void delayed_work_timer_fn(struct timer_list *t); + +/* + * The first word is the work queue pointer and the flags rolled into + * one + */ +#define work_data_bits(work) ((unsigned long *)(&(work)->data)) + +enum { + WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */ + WORK_STRUCT_INACTIVE_BIT= 1, /* work item is inactive */ + WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */ + WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */ +#ifdef CONFIG_DEBUG_OBJECTS_WORK + WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */ + WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */ +#else + WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */ +#endif + + WORK_STRUCT_COLOR_BITS = 4, + + WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT, + WORK_STRUCT_INACTIVE = 1 << WORK_STRUCT_INACTIVE_BIT, + WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT, + WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT, +#ifdef CONFIG_DEBUG_OBJECTS_WORK + WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT, +#else + WORK_STRUCT_STATIC = 0, +#endif + + WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS), + + /* not bound to any CPU, prefer the local CPU */ + WORK_CPU_UNBOUND = NR_CPUS, + + /* + * Reserve 8 bits off of pwq pointer w/ debugobjects turned off. + * This makes pwqs aligned to 256 bytes and allows 16 workqueue + * flush colors. + */ + WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT + + WORK_STRUCT_COLOR_BITS, + + /* data contains off-queue information when !WORK_STRUCT_PWQ */ + WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT, + + __WORK_OFFQ_CANCELING = WORK_OFFQ_FLAG_BASE, + + /* + * When a work item is off queue, its high bits point to the last + * pool it was on. Cap at 31 bits and use the highest number to + * indicate that no pool is associated. + */ + WORK_OFFQ_FLAG_BITS = 1, + WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS, + WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT, + WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31, + + /* bit mask for work_busy() return values */ + WORK_BUSY_PENDING = 1 << 0, + WORK_BUSY_RUNNING = 1 << 1, + + /* maximum string length for set_worker_desc() */ + WORKER_DESC_LEN = 24, +}; + +/* Convenience constants - of type 'unsigned long', not 'enum'! */ +#define WORK_OFFQ_CANCELING (1ul << __WORK_OFFQ_CANCELING) +#define WORK_OFFQ_POOL_NONE ((1ul << WORK_OFFQ_POOL_BITS) - 1) +#define WORK_STRUCT_NO_POOL (WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT) + +#define WORK_STRUCT_FLAG_MASK ((1ul << WORK_STRUCT_FLAG_BITS) - 1) +#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK) + +struct work_struct { + atomic_long_t data; + struct list_head entry; + work_func_t func; +#ifdef CONFIG_LOCKDEP + struct lockdep_map lockdep_map; +#endif +}; + +#define WORK_DATA_INIT() ATOMIC_LONG_INIT((unsigned long)WORK_STRUCT_NO_POOL) +#define WORK_DATA_STATIC_INIT() \ + ATOMIC_LONG_INIT((unsigned long)(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)) + +struct delayed_work { + struct work_struct work; + struct timer_list timer; + + /* target workqueue and CPU ->timer uses to queue ->work */ + struct workqueue_struct *wq; + int cpu; +}; + +struct rcu_work { + struct work_struct work; + struct rcu_head rcu; + + /* target workqueue ->rcu uses to queue ->work */ + struct workqueue_struct *wq; +}; + +/** + * struct workqueue_attrs - A struct for workqueue attributes. + * + * This can be used to change attributes of an unbound workqueue. + */ +struct workqueue_attrs { + /** + * @nice: nice level + */ + int nice; + + /** + * @cpumask: allowed CPUs + */ + cpumask_var_t cpumask; + + /** + * @no_numa: disable NUMA affinity + * + * Unlike other fields, ``no_numa`` isn't a property of a worker_pool. It + * only modifies how :c:func:`apply_workqueue_attrs` select pools and thus + * doesn't participate in pool hash calculations or equality comparisons. + */ + bool no_numa; +}; + +static inline struct delayed_work *to_delayed_work(struct work_struct *work) +{ + return container_of(work, struct delayed_work, work); +} + +static inline struct rcu_work *to_rcu_work(struct work_struct *work) +{ + return container_of(work, struct rcu_work, work); +} + +struct execute_work { + struct work_struct work; +}; + +#ifdef CONFIG_LOCKDEP +/* + * NB: because we have to copy the lockdep_map, setting _key + * here is required, otherwise it could get initialised to the + * copy of the lockdep_map! + */ +#define __WORK_INIT_LOCKDEP_MAP(n, k) \ + .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k), +#else +#define __WORK_INIT_LOCKDEP_MAP(n, k) +#endif + +#define __WORK_INITIALIZER(n, f) { \ + .data = WORK_DATA_STATIC_INIT(), \ + .entry = { &(n).entry, &(n).entry }, \ + .func = (f), \ + __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \ + } + +#define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \ + .work = __WORK_INITIALIZER((n).work, (f)), \ + .timer = __TIMER_INITIALIZER(delayed_work_timer_fn,\ + (tflags) | TIMER_IRQSAFE), \ + } + +#define DECLARE_WORK(n, f) \ + struct work_struct n = __WORK_INITIALIZER(n, f) + +#define DECLARE_DELAYED_WORK(n, f) \ + struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0) + +#define DECLARE_DEFERRABLE_WORK(n, f) \ + struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE) + +#ifdef CONFIG_DEBUG_OBJECTS_WORK +extern void __init_work(struct work_struct *work, int onstack); +extern void destroy_work_on_stack(struct work_struct *work); +extern void destroy_delayed_work_on_stack(struct delayed_work *work); +static inline unsigned int work_static(struct work_struct *work) +{ + return *work_data_bits(work) & WORK_STRUCT_STATIC; +} +#else +static inline void __init_work(struct work_struct *work, int onstack) { } +static inline void destroy_work_on_stack(struct work_struct *work) { } +static inline void destroy_delayed_work_on_stack(struct delayed_work *work) { } +static inline unsigned int work_static(struct work_struct *work) { return 0; } +#endif + +/* + * initialize all of a work item in one go + * + * NOTE! No point in using "atomic_long_set()": using a direct + * assignment of the work data initializer allows the compiler + * to generate better code. + */ +#ifdef CONFIG_LOCKDEP +#define __INIT_WORK_KEY(_work, _func, _onstack, _key) \ + do { \ + __init_work((_work), _onstack); \ + (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ + lockdep_init_map(&(_work)->lockdep_map, "(work_completion)"#_work, (_key), 0); \ + INIT_LIST_HEAD(&(_work)->entry); \ + (_work)->func = (_func); \ + } while (0) +#else +#define __INIT_WORK_KEY(_work, _func, _onstack, _key) \ + do { \ + __init_work((_work), _onstack); \ + (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \ + INIT_LIST_HEAD(&(_work)->entry); \ + (_work)->func = (_func); \ + } while (0) +#endif + +#define __INIT_WORK(_work, _func, _onstack) \ + do { \ + static __maybe_unused struct lock_class_key __key; \ + \ + __INIT_WORK_KEY(_work, _func, _onstack, &__key); \ + } while (0) + +#define INIT_WORK(_work, _func) \ + __INIT_WORK((_work), (_func), 0) + +#define INIT_WORK_ONSTACK(_work, _func) \ + __INIT_WORK((_work), (_func), 1) + +#define INIT_WORK_ONSTACK_KEY(_work, _func, _key) \ + __INIT_WORK_KEY((_work), (_func), 1, _key) + +#define __INIT_DELAYED_WORK(_work, _func, _tflags) \ + do { \ + INIT_WORK(&(_work)->work, (_func)); \ + __init_timer(&(_work)->timer, \ + delayed_work_timer_fn, \ + (_tflags) | TIMER_IRQSAFE); \ + } while (0) + +#define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags) \ + do { \ + INIT_WORK_ONSTACK(&(_work)->work, (_func)); \ + __init_timer_on_stack(&(_work)->timer, \ + delayed_work_timer_fn, \ + (_tflags) | TIMER_IRQSAFE); \ + } while (0) + +#define INIT_DELAYED_WORK(_work, _func) \ + __INIT_DELAYED_WORK(_work, _func, 0) + +#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \ + __INIT_DELAYED_WORK_ONSTACK(_work, _func, 0) + +#define INIT_DEFERRABLE_WORK(_work, _func) \ + __INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE) + +#define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func) \ + __INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE) + +#define INIT_RCU_WORK(_work, _func) \ + INIT_WORK(&(_work)->work, (_func)) + +#define INIT_RCU_WORK_ONSTACK(_work, _func) \ + INIT_WORK_ONSTACK(&(_work)->work, (_func)) + +/** + * work_pending - Find out whether a work item is currently pending + * @work: The work item in question + */ +#define work_pending(work) \ + test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)) + +/** + * delayed_work_pending - Find out whether a delayable work item is currently + * pending + * @w: The work item in question + */ +#define delayed_work_pending(w) \ + work_pending(&(w)->work) + +/* + * Workqueue flags and constants. For details, please refer to + * Documentation/core-api/workqueue.rst. + */ +enum { + WQ_UNBOUND = 1 << 1, /* not bound to any cpu */ + WQ_FREEZABLE = 1 << 2, /* freeze during suspend */ + WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */ + WQ_HIGHPRI = 1 << 4, /* high priority */ + WQ_CPU_INTENSIVE = 1 << 5, /* cpu intensive workqueue */ + WQ_SYSFS = 1 << 6, /* visible in sysfs, see workqueue_sysfs_register() */ + + /* + * Per-cpu workqueues are generally preferred because they tend to + * show better performance thanks to cache locality. Per-cpu + * workqueues exclude the scheduler from choosing the CPU to + * execute the worker threads, which has an unfortunate side effect + * of increasing power consumption. + * + * The scheduler considers a CPU idle if it doesn't have any task + * to execute and tries to keep idle cores idle to conserve power; + * however, for example, a per-cpu work item scheduled from an + * interrupt handler on an idle CPU will force the scheduler to + * execute the work item on that CPU breaking the idleness, which in + * turn may lead to more scheduling choices which are sub-optimal + * in terms of power consumption. + * + * Workqueues marked with WQ_POWER_EFFICIENT are per-cpu by default + * but become unbound if workqueue.power_efficient kernel param is + * specified. Per-cpu workqueues which are identified to + * contribute significantly to power-consumption are identified and + * marked with this flag and enabling the power_efficient mode + * leads to noticeable power saving at the cost of small + * performance disadvantage. + * + * http://thread.gmane.org/gmane.linux.kernel/1480396 + */ + WQ_POWER_EFFICIENT = 1 << 7, + + __WQ_DRAINING = 1 << 16, /* internal: workqueue is draining */ + __WQ_ORDERED = 1 << 17, /* internal: workqueue is ordered */ + __WQ_LEGACY = 1 << 18, /* internal: create*_workqueue() */ + __WQ_ORDERED_EXPLICIT = 1 << 19, /* internal: alloc_ordered_workqueue() */ + + WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */ + WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */ + WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2, +}; + +/* unbound wq's aren't per-cpu, scale max_active according to #cpus */ +#define WQ_UNBOUND_MAX_ACTIVE \ + max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU) + +/* + * System-wide workqueues which are always present. + * + * system_wq is the one used by schedule[_delayed]_work[_on](). + * Multi-CPU multi-threaded. There are users which expect relatively + * short queue flush time. Don't queue works which can run for too + * long. + * + * system_highpri_wq is similar to system_wq but for work items which + * require WQ_HIGHPRI. + * + * system_long_wq is similar to system_wq but may host long running + * works. Queue flushing might take relatively long. + * + * system_unbound_wq is unbound workqueue. Workers are not bound to + * any specific CPU, not concurrency managed, and all queued works are + * executed immediately as long as max_active limit is not reached and + * resources are available. + * + * system_freezable_wq is equivalent to system_wq except that it's + * freezable. + * + * *_power_efficient_wq are inclined towards saving power and converted + * into WQ_UNBOUND variants if 'wq_power_efficient' is enabled; otherwise, + * they are same as their non-power-efficient counterparts - e.g. + * system_power_efficient_wq is identical to system_wq if + * 'wq_power_efficient' is disabled. See WQ_POWER_EFFICIENT for more info. + */ +extern struct workqueue_struct *system_wq; +extern struct workqueue_struct *system_highpri_wq; +extern struct workqueue_struct *system_long_wq; +extern struct workqueue_struct *system_unbound_wq; +extern struct workqueue_struct *system_freezable_wq; +extern struct workqueue_struct *system_power_efficient_wq; +extern struct workqueue_struct *system_freezable_power_efficient_wq; + +/** + * alloc_workqueue - allocate a workqueue + * @fmt: printf format for the name of the workqueue + * @flags: WQ_* flags + * @max_active: max in-flight work items, 0 for default + * remaining args: args for @fmt + * + * Allocate a workqueue with the specified parameters. For detailed + * information on WQ_* flags, please refer to + * Documentation/core-api/workqueue.rst. + * + * RETURNS: + * Pointer to the allocated workqueue on success, %NULL on failure. + */ +__printf(1, 4) struct workqueue_struct * +alloc_workqueue(const char *fmt, unsigned int flags, int max_active, ...); + +/** + * alloc_ordered_workqueue - allocate an ordered workqueue + * @fmt: printf format for the name of the workqueue + * @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful) + * @args: args for @fmt + * + * Allocate an ordered workqueue. An ordered workqueue executes at + * most one work item at any given time in the queued order. They are + * implemented as unbound workqueues with @max_active of one. + * + * RETURNS: + * Pointer to the allocated workqueue on success, %NULL on failure. + */ +#define alloc_ordered_workqueue(fmt, flags, args...) \ + alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | \ + __WQ_ORDERED_EXPLICIT | (flags), 1, ##args) + +#define create_workqueue(name) \ + alloc_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, 1, (name)) +#define create_freezable_workqueue(name) \ + alloc_workqueue("%s", __WQ_LEGACY | WQ_FREEZABLE | WQ_UNBOUND | \ + WQ_MEM_RECLAIM, 1, (name)) +#define create_singlethread_workqueue(name) \ + alloc_ordered_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, name) + +extern void destroy_workqueue(struct workqueue_struct *wq); + +struct workqueue_attrs *alloc_workqueue_attrs(void); +void free_workqueue_attrs(struct workqueue_attrs *attrs); +int apply_workqueue_attrs(struct workqueue_struct *wq, + const struct workqueue_attrs *attrs); +int workqueue_set_unbound_cpumask(cpumask_var_t cpumask); + +extern bool queue_work_on(int cpu, struct workqueue_struct *wq, + struct work_struct *work); +extern bool queue_work_node(int node, struct workqueue_struct *wq, + struct work_struct *work); +extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq, + struct delayed_work *work, unsigned long delay); +extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq, + struct delayed_work *dwork, unsigned long delay); +extern bool queue_rcu_work(struct workqueue_struct *wq, struct rcu_work *rwork); + +extern void __flush_workqueue(struct workqueue_struct *wq); +extern void drain_workqueue(struct workqueue_struct *wq); + +extern int schedule_on_each_cpu(work_func_t func); + +int execute_in_process_context(work_func_t fn, struct execute_work *); + +extern bool flush_work(struct work_struct *work); +extern bool cancel_work(struct work_struct *work); +extern bool cancel_work_sync(struct work_struct *work); + +extern bool flush_delayed_work(struct delayed_work *dwork); +extern bool cancel_delayed_work(struct delayed_work *dwork); +extern bool cancel_delayed_work_sync(struct delayed_work *dwork); + +extern bool flush_rcu_work(struct rcu_work *rwork); + +extern void workqueue_set_max_active(struct workqueue_struct *wq, + int max_active); +extern struct work_struct *current_work(void); +extern bool current_is_workqueue_rescuer(void); +extern bool workqueue_congested(int cpu, struct workqueue_struct *wq); +extern unsigned int work_busy(struct work_struct *work); +extern __printf(1, 2) void set_worker_desc(const char *fmt, ...); +extern void print_worker_info(const char *log_lvl, struct task_struct *task); +extern void show_all_workqueues(void); +extern void show_one_workqueue(struct workqueue_struct *wq); +extern void wq_worker_comm(char *buf, size_t size, struct task_struct *task); + +/** + * queue_work - queue work on a workqueue + * @wq: workqueue to use + * @work: work to queue + * + * Returns %false if @work was already on a queue, %true otherwise. + * + * We queue the work to the CPU on which it was submitted, but if the CPU dies + * it can be processed by another CPU. + * + * Memory-ordering properties: If it returns %true, guarantees that all stores + * preceding the call to queue_work() in the program order will be visible from + * the CPU which will execute @work by the time such work executes, e.g., + * + * { x is initially 0 } + * + * CPU0 CPU1 + * + * WRITE_ONCE(x, 1); [ @work is being executed ] + * r0 = queue_work(wq, work); r1 = READ_ONCE(x); + * + * Forbids: r0 == true && r1 == 0 + */ +static inline bool queue_work(struct workqueue_struct *wq, + struct work_struct *work) +{ + return queue_work_on(WORK_CPU_UNBOUND, wq, work); +} + +/** + * queue_delayed_work - queue work on a workqueue after delay + * @wq: workqueue to use + * @dwork: delayable work to queue + * @delay: number of jiffies to wait before queueing + * + * Equivalent to queue_delayed_work_on() but tries to use the local CPU. + */ +static inline bool queue_delayed_work(struct workqueue_struct *wq, + struct delayed_work *dwork, + unsigned long delay) +{ + return queue_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay); +} + +/** + * mod_delayed_work - modify delay of or queue a delayed work + * @wq: workqueue to use + * @dwork: work to queue + * @delay: number of jiffies to wait before queueing + * + * mod_delayed_work_on() on local CPU. + */ +static inline bool mod_delayed_work(struct workqueue_struct *wq, + struct delayed_work *dwork, + unsigned long delay) +{ + return mod_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay); +} + +/** + * schedule_work_on - put work task on a specific cpu + * @cpu: cpu to put the work task on + * @work: job to be done + * + * This puts a job on a specific cpu + */ +static inline bool schedule_work_on(int cpu, struct work_struct *work) +{ + return queue_work_on(cpu, system_wq, work); +} + +/** + * schedule_work - put work task in global workqueue + * @work: job to be done + * + * Returns %false if @work was already on the kernel-global workqueue and + * %true otherwise. + * + * This puts a job in the kernel-global workqueue if it was not already + * queued and leaves it in the same position on the kernel-global + * workqueue otherwise. + * + * Shares the same memory-ordering properties of queue_work(), cf. the + * DocBook header of queue_work(). + */ +static inline bool schedule_work(struct work_struct *work) +{ + return queue_work(system_wq, work); +} + +/* + * Detect attempt to flush system-wide workqueues at compile time when possible. + * + * See https://lkml.kernel.org/r/49925af7-78a8-a3dd-bce6-cfc02e1a9236@I-love.SAKURA.ne.jp + * for reasons and steps for converting system-wide workqueues into local workqueues. + */ +extern void __warn_flushing_systemwide_wq(void) + __compiletime_warning("Please avoid flushing system-wide workqueues."); + +/** + * flush_scheduled_work - ensure that any scheduled work has run to completion. + * + * Forces execution of the kernel-global workqueue and blocks until its + * completion. + * + * It's very easy to get into trouble if you don't take great care. + * Either of the following situations will lead to deadlock: + * + * One of the work items currently on the workqueue needs to acquire + * a lock held by your code or its caller. + * + * Your code is running in the context of a work routine. + * + * They will be detected by lockdep when they occur, but the first might not + * occur very often. It depends on what work items are on the workqueue and + * what locks they need, which you have no control over. + * + * In most situations flushing the entire workqueue is overkill; you merely + * need to know that a particular work item isn't queued and isn't running. + * In such cases you should use cancel_delayed_work_sync() or + * cancel_work_sync() instead. + * + * Please stop calling this function! A conversion to stop flushing system-wide + * workqueues is in progress. This function will be removed after all in-tree + * users stopped calling this function. + */ +/* + * The background of commit 771c035372a036f8 ("deprecate the + * '__deprecated' attribute warnings entirely and for good") is that, + * since Linus builds all modules between every single pull he does, + * the standard kernel build needs to be _clean_ in order to be able to + * notice when new problems happen. Therefore, don't emit warning while + * there are in-tree users. + */ +#define flush_scheduled_work() \ +({ \ + if (0) \ + __warn_flushing_systemwide_wq(); \ + __flush_workqueue(system_wq); \ +}) + +/* + * Although there is no longer in-tree caller, for now just emit warning + * in order to give out-of-tree callers time to update. + */ +#define flush_workqueue(wq) \ +({ \ + struct workqueue_struct *_wq = (wq); \ + \ + if ((__builtin_constant_p(_wq == system_wq) && \ + _wq == system_wq) || \ + (__builtin_constant_p(_wq == system_highpri_wq) && \ + _wq == system_highpri_wq) || \ + (__builtin_constant_p(_wq == system_long_wq) && \ + _wq == system_long_wq) || \ + (__builtin_constant_p(_wq == system_unbound_wq) && \ + _wq == system_unbound_wq) || \ + (__builtin_constant_p(_wq == system_freezable_wq) && \ + _wq == system_freezable_wq) || \ + (__builtin_constant_p(_wq == system_power_efficient_wq) && \ + _wq == system_power_efficient_wq) || \ + (__builtin_constant_p(_wq == system_freezable_power_efficient_wq) && \ + _wq == system_freezable_power_efficient_wq)) \ + __warn_flushing_systemwide_wq(); \ + __flush_workqueue(_wq); \ +}) + +/** + * schedule_delayed_work_on - queue work in global workqueue on CPU after delay + * @cpu: cpu to use + * @dwork: job to be done + * @delay: number of jiffies to wait + * + * After waiting for a given time this puts a job in the kernel-global + * workqueue on the specified CPU. + */ +static inline bool schedule_delayed_work_on(int cpu, struct delayed_work *dwork, + unsigned long delay) +{ + return queue_delayed_work_on(cpu, system_wq, dwork, delay); +} + +/** + * schedule_delayed_work - put work task in global workqueue after delay + * @dwork: job to be done + * @delay: number of jiffies to wait or 0 for immediate execution + * + * After waiting for a given time this puts a job in the kernel-global + * workqueue. + */ +static inline bool schedule_delayed_work(struct delayed_work *dwork, + unsigned long delay) +{ + return queue_delayed_work(system_wq, dwork, delay); +} + +#ifndef CONFIG_SMP +static inline long work_on_cpu(int cpu, long (*fn)(void *), void *arg) +{ + return fn(arg); +} +static inline long work_on_cpu_safe(int cpu, long (*fn)(void *), void *arg) +{ + return fn(arg); +} +#else +long work_on_cpu_key(int cpu, long (*fn)(void *), + void *arg, struct lock_class_key *key); +/* + * A new key is defined for each caller to make sure the work + * associated with the function doesn't share its locking class. + */ +#define work_on_cpu(_cpu, _fn, _arg) \ +({ \ + static struct lock_class_key __key; \ + \ + work_on_cpu_key(_cpu, _fn, _arg, &__key); \ +}) + +long work_on_cpu_safe_key(int cpu, long (*fn)(void *), + void *arg, struct lock_class_key *key); + +/* + * A new key is defined for each caller to make sure the work + * associated with the function doesn't share its locking class. + */ +#define work_on_cpu_safe(_cpu, _fn, _arg) \ +({ \ + static struct lock_class_key __key; \ + \ + work_on_cpu_safe_key(_cpu, _fn, _arg, &__key); \ +}) +#endif /* CONFIG_SMP */ + +#ifdef CONFIG_FREEZER +extern void freeze_workqueues_begin(void); +extern bool freeze_workqueues_busy(void); +extern void thaw_workqueues(void); +#endif /* CONFIG_FREEZER */ + +#ifdef CONFIG_SYSFS +int workqueue_sysfs_register(struct workqueue_struct *wq); +#else /* CONFIG_SYSFS */ +static inline int workqueue_sysfs_register(struct workqueue_struct *wq) +{ return 0; } +#endif /* CONFIG_SYSFS */ + +#ifdef CONFIG_WQ_WATCHDOG +void wq_watchdog_touch(int cpu); +#else /* CONFIG_WQ_WATCHDOG */ +static inline void wq_watchdog_touch(int cpu) { } +#endif /* CONFIG_WQ_WATCHDOG */ + +#ifdef CONFIG_SMP +int workqueue_prepare_cpu(unsigned int cpu); +int workqueue_online_cpu(unsigned int cpu); +int workqueue_offline_cpu(unsigned int cpu); +#endif + +void __init workqueue_init_early(void); +void __init workqueue_init(void); + +#endif |