mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 16:38:12 +00:00
8bee9dd953
The syntax without dots is available since commit 43756e347f
("scripts/kernel-doc: Add support for named variable macro arguments").
The same HTML output is produced with and without this patch.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
714 lines
23 KiB
C
714 lines
23 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* workqueue.h --- work queue handling for Linux.
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*/
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#ifndef _LINUX_WORKQUEUE_H
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#define _LINUX_WORKQUEUE_H
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#include <linux/timer.h>
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#include <linux/linkage.h>
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#include <linux/bitops.h>
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#include <linux/lockdep.h>
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#include <linux/threads.h>
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#include <linux/atomic.h>
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#include <linux/cpumask.h>
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#include <linux/rcupdate.h>
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struct workqueue_struct;
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struct work_struct;
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typedef void (*work_func_t)(struct work_struct *work);
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void delayed_work_timer_fn(struct timer_list *t);
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/*
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* The first word is the work queue pointer and the flags rolled into
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* one
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*/
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#define work_data_bits(work) ((unsigned long *)(&(work)->data))
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enum {
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WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
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WORK_STRUCT_INACTIVE_BIT= 1, /* work item is inactive */
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WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */
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WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */
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#ifdef CONFIG_DEBUG_OBJECTS_WORK
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WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */
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WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */
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#else
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WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
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#endif
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WORK_STRUCT_COLOR_BITS = 4,
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WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
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WORK_STRUCT_INACTIVE = 1 << WORK_STRUCT_INACTIVE_BIT,
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WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT,
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WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
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#ifdef CONFIG_DEBUG_OBJECTS_WORK
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WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
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#else
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WORK_STRUCT_STATIC = 0,
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#endif
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WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS),
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/* not bound to any CPU, prefer the local CPU */
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WORK_CPU_UNBOUND = NR_CPUS,
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/*
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* Reserve 8 bits off of pwq pointer w/ debugobjects turned off.
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* This makes pwqs aligned to 256 bytes and allows 16 workqueue
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* flush colors.
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*/
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WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
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WORK_STRUCT_COLOR_BITS,
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/* data contains off-queue information when !WORK_STRUCT_PWQ */
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WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT,
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__WORK_OFFQ_CANCELING = WORK_OFFQ_FLAG_BASE,
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WORK_OFFQ_CANCELING = (1 << __WORK_OFFQ_CANCELING),
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/*
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* When a work item is off queue, its high bits point to the last
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* pool it was on. Cap at 31 bits and use the highest number to
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* indicate that no pool is associated.
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*/
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WORK_OFFQ_FLAG_BITS = 1,
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WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
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WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
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WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
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WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1,
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/* convenience constants */
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WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
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WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
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WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
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/* bit mask for work_busy() return values */
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WORK_BUSY_PENDING = 1 << 0,
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WORK_BUSY_RUNNING = 1 << 1,
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/* maximum string length for set_worker_desc() */
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WORKER_DESC_LEN = 24,
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};
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struct work_struct {
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atomic_long_t data;
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struct list_head entry;
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work_func_t func;
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#ifdef CONFIG_LOCKDEP
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struct lockdep_map lockdep_map;
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#endif
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};
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#define WORK_DATA_INIT() ATOMIC_LONG_INIT((unsigned long)WORK_STRUCT_NO_POOL)
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#define WORK_DATA_STATIC_INIT() \
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ATOMIC_LONG_INIT((unsigned long)(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC))
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struct delayed_work {
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struct work_struct work;
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struct timer_list timer;
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/* target workqueue and CPU ->timer uses to queue ->work */
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struct workqueue_struct *wq;
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int cpu;
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};
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struct rcu_work {
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struct work_struct work;
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struct rcu_head rcu;
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/* target workqueue ->rcu uses to queue ->work */
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struct workqueue_struct *wq;
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};
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/**
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* struct workqueue_attrs - A struct for workqueue attributes.
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*
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* This can be used to change attributes of an unbound workqueue.
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*/
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struct workqueue_attrs {
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/**
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* @nice: nice level
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*/
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int nice;
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/**
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* @cpumask: allowed CPUs
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*/
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cpumask_var_t cpumask;
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/**
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* @no_numa: disable NUMA affinity
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*
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* Unlike other fields, ``no_numa`` isn't a property of a worker_pool. It
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* only modifies how :c:func:`apply_workqueue_attrs` select pools and thus
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* doesn't participate in pool hash calculations or equality comparisons.
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*/
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bool no_numa;
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};
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static inline struct delayed_work *to_delayed_work(struct work_struct *work)
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{
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return container_of(work, struct delayed_work, work);
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}
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static inline struct rcu_work *to_rcu_work(struct work_struct *work)
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{
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return container_of(work, struct rcu_work, work);
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}
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struct execute_work {
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struct work_struct work;
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};
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#ifdef CONFIG_LOCKDEP
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/*
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* NB: because we have to copy the lockdep_map, setting _key
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* here is required, otherwise it could get initialised to the
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* copy of the lockdep_map!
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*/
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#define __WORK_INIT_LOCKDEP_MAP(n, k) \
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.lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
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#else
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#define __WORK_INIT_LOCKDEP_MAP(n, k)
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#endif
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#define __WORK_INITIALIZER(n, f) { \
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.data = WORK_DATA_STATIC_INIT(), \
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.entry = { &(n).entry, &(n).entry }, \
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.func = (f), \
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__WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
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}
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#define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \
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.work = __WORK_INITIALIZER((n).work, (f)), \
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.timer = __TIMER_INITIALIZER(delayed_work_timer_fn,\
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(tflags) | TIMER_IRQSAFE), \
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}
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#define DECLARE_WORK(n, f) \
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struct work_struct n = __WORK_INITIALIZER(n, f)
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#define DECLARE_DELAYED_WORK(n, f) \
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struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0)
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#define DECLARE_DEFERRABLE_WORK(n, f) \
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struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE)
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#ifdef CONFIG_DEBUG_OBJECTS_WORK
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extern void __init_work(struct work_struct *work, int onstack);
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extern void destroy_work_on_stack(struct work_struct *work);
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extern void destroy_delayed_work_on_stack(struct delayed_work *work);
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static inline unsigned int work_static(struct work_struct *work)
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{
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return *work_data_bits(work) & WORK_STRUCT_STATIC;
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}
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#else
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static inline void __init_work(struct work_struct *work, int onstack) { }
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static inline void destroy_work_on_stack(struct work_struct *work) { }
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static inline void destroy_delayed_work_on_stack(struct delayed_work *work) { }
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static inline unsigned int work_static(struct work_struct *work) { return 0; }
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#endif
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/*
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* initialize all of a work item in one go
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*
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* NOTE! No point in using "atomic_long_set()": using a direct
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* assignment of the work data initializer allows the compiler
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* to generate better code.
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*/
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#ifdef CONFIG_LOCKDEP
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#define __INIT_WORK(_work, _func, _onstack) \
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do { \
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static struct lock_class_key __key; \
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\
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__init_work((_work), _onstack); \
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(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
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lockdep_init_map(&(_work)->lockdep_map, "(work_completion)"#_work, &__key, 0); \
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INIT_LIST_HEAD(&(_work)->entry); \
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(_work)->func = (_func); \
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} while (0)
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#else
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#define __INIT_WORK(_work, _func, _onstack) \
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do { \
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__init_work((_work), _onstack); \
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(_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
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INIT_LIST_HEAD(&(_work)->entry); \
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(_work)->func = (_func); \
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} while (0)
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#endif
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#define INIT_WORK(_work, _func) \
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__INIT_WORK((_work), (_func), 0)
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#define INIT_WORK_ONSTACK(_work, _func) \
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__INIT_WORK((_work), (_func), 1)
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#define __INIT_DELAYED_WORK(_work, _func, _tflags) \
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do { \
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INIT_WORK(&(_work)->work, (_func)); \
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__init_timer(&(_work)->timer, \
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delayed_work_timer_fn, \
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(_tflags) | TIMER_IRQSAFE); \
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} while (0)
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#define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags) \
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do { \
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INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
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__init_timer_on_stack(&(_work)->timer, \
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delayed_work_timer_fn, \
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(_tflags) | TIMER_IRQSAFE); \
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} while (0)
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#define INIT_DELAYED_WORK(_work, _func) \
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__INIT_DELAYED_WORK(_work, _func, 0)
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#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
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__INIT_DELAYED_WORK_ONSTACK(_work, _func, 0)
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#define INIT_DEFERRABLE_WORK(_work, _func) \
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__INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE)
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#define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func) \
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__INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE)
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#define INIT_RCU_WORK(_work, _func) \
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INIT_WORK(&(_work)->work, (_func))
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#define INIT_RCU_WORK_ONSTACK(_work, _func) \
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INIT_WORK_ONSTACK(&(_work)->work, (_func))
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/**
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* work_pending - Find out whether a work item is currently pending
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* @work: The work item in question
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*/
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#define work_pending(work) \
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test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
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/**
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* delayed_work_pending - Find out whether a delayable work item is currently
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* pending
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* @w: The work item in question
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*/
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#define delayed_work_pending(w) \
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work_pending(&(w)->work)
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/*
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* Workqueue flags and constants. For details, please refer to
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* Documentation/core-api/workqueue.rst.
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*/
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enum {
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WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
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WQ_FREEZABLE = 1 << 2, /* freeze during suspend */
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WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */
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WQ_HIGHPRI = 1 << 4, /* high priority */
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WQ_CPU_INTENSIVE = 1 << 5, /* cpu intensive workqueue */
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WQ_SYSFS = 1 << 6, /* visible in sysfs, see workqueue_sysfs_register() */
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/*
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* Per-cpu workqueues are generally preferred because they tend to
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* show better performance thanks to cache locality. Per-cpu
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* workqueues exclude the scheduler from choosing the CPU to
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* execute the worker threads, which has an unfortunate side effect
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* of increasing power consumption.
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*
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* The scheduler considers a CPU idle if it doesn't have any task
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* to execute and tries to keep idle cores idle to conserve power;
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* however, for example, a per-cpu work item scheduled from an
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* interrupt handler on an idle CPU will force the scheduler to
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* execute the work item on that CPU breaking the idleness, which in
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* turn may lead to more scheduling choices which are sub-optimal
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* in terms of power consumption.
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*
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* Workqueues marked with WQ_POWER_EFFICIENT are per-cpu by default
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* but become unbound if workqueue.power_efficient kernel param is
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* specified. Per-cpu workqueues which are identified to
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* contribute significantly to power-consumption are identified and
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* marked with this flag and enabling the power_efficient mode
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* leads to noticeable power saving at the cost of small
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* performance disadvantage.
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*
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* http://thread.gmane.org/gmane.linux.kernel/1480396
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*/
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WQ_POWER_EFFICIENT = 1 << 7,
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__WQ_DRAINING = 1 << 16, /* internal: workqueue is draining */
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__WQ_ORDERED = 1 << 17, /* internal: workqueue is ordered */
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__WQ_LEGACY = 1 << 18, /* internal: create*_workqueue() */
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__WQ_ORDERED_EXPLICIT = 1 << 19, /* internal: alloc_ordered_workqueue() */
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WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
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WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
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WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
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};
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/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
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#define WQ_UNBOUND_MAX_ACTIVE \
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max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
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/*
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* System-wide workqueues which are always present.
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*
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* system_wq is the one used by schedule[_delayed]_work[_on]().
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* Multi-CPU multi-threaded. There are users which expect relatively
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* short queue flush time. Don't queue works which can run for too
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* long.
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*
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* system_highpri_wq is similar to system_wq but for work items which
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* require WQ_HIGHPRI.
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*
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* system_long_wq is similar to system_wq but may host long running
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* works. Queue flushing might take relatively long.
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*
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* system_unbound_wq is unbound workqueue. Workers are not bound to
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* any specific CPU, not concurrency managed, and all queued works are
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* executed immediately as long as max_active limit is not reached and
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* resources are available.
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*
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* system_freezable_wq is equivalent to system_wq except that it's
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* freezable.
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*
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* *_power_efficient_wq are inclined towards saving power and converted
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* into WQ_UNBOUND variants if 'wq_power_efficient' is enabled; otherwise,
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* they are same as their non-power-efficient counterparts - e.g.
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* system_power_efficient_wq is identical to system_wq if
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* 'wq_power_efficient' is disabled. See WQ_POWER_EFFICIENT for more info.
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*/
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extern struct workqueue_struct *system_wq;
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extern struct workqueue_struct *system_highpri_wq;
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extern struct workqueue_struct *system_long_wq;
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extern struct workqueue_struct *system_unbound_wq;
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extern struct workqueue_struct *system_freezable_wq;
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extern struct workqueue_struct *system_power_efficient_wq;
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extern struct workqueue_struct *system_freezable_power_efficient_wq;
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/**
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* alloc_workqueue - allocate a workqueue
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* @fmt: printf format for the name of the workqueue
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* @flags: WQ_* flags
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* @max_active: max in-flight work items, 0 for default
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* remaining args: args for @fmt
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*
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* Allocate a workqueue with the specified parameters. For detailed
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* information on WQ_* flags, please refer to
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* Documentation/core-api/workqueue.rst.
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*
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* RETURNS:
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* Pointer to the allocated workqueue on success, %NULL on failure.
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*/
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__printf(1, 4) struct workqueue_struct *
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alloc_workqueue(const char *fmt, unsigned int flags, int max_active, ...);
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/**
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* alloc_ordered_workqueue - allocate an ordered workqueue
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* @fmt: printf format for the name of the workqueue
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* @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
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* @args: args for @fmt
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*
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* Allocate an ordered workqueue. An ordered workqueue executes at
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* most one work item at any given time in the queued order. They are
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* implemented as unbound workqueues with @max_active of one.
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*
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* RETURNS:
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* Pointer to the allocated workqueue on success, %NULL on failure.
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*/
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#define alloc_ordered_workqueue(fmt, flags, args...) \
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alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | \
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__WQ_ORDERED_EXPLICIT | (flags), 1, ##args)
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#define create_workqueue(name) \
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alloc_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, 1, (name))
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#define create_freezable_workqueue(name) \
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alloc_workqueue("%s", __WQ_LEGACY | WQ_FREEZABLE | WQ_UNBOUND | \
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WQ_MEM_RECLAIM, 1, (name))
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#define create_singlethread_workqueue(name) \
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alloc_ordered_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, name)
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extern void destroy_workqueue(struct workqueue_struct *wq);
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struct workqueue_attrs *alloc_workqueue_attrs(void);
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void free_workqueue_attrs(struct workqueue_attrs *attrs);
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int apply_workqueue_attrs(struct workqueue_struct *wq,
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const struct workqueue_attrs *attrs);
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int workqueue_set_unbound_cpumask(cpumask_var_t cpumask);
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extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
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struct work_struct *work);
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extern bool queue_work_node(int node, struct workqueue_struct *wq,
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struct work_struct *work);
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extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
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struct delayed_work *work, unsigned long delay);
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extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
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struct delayed_work *dwork, unsigned long delay);
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|
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_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(int cpu, long (*fn)(void *), void *arg);
|
|
long work_on_cpu_safe(int cpu, long (*fn)(void *), void *arg);
|
|
#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
|