diff options
Diffstat (limited to 'include/linux/workqueue.h')
| -rw-r--r-- | include/linux/workqueue.h | 220 |
1 files changed, 197 insertions, 23 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 8afab27cdbc2..594521ba0d43 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -11,6 +11,7 @@ #include <linux/lockdep.h> #include <linux/threads.h> #include <linux/atomic.h> +#include <linux/cpumask.h> struct workqueue_struct; @@ -68,7 +69,7 @@ enum { WORK_STRUCT_COLOR_BITS, /* data contains off-queue information when !WORK_STRUCT_PWQ */ - WORK_OFFQ_FLAG_BASE = WORK_STRUCT_FLAG_BITS, + WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT, WORK_OFFQ_CANCELING = (1 << WORK_OFFQ_FLAG_BASE), @@ -91,6 +92,9 @@ enum { /* 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, }; struct work_struct { @@ -115,6 +119,20 @@ struct delayed_work { int cpu; }; +/* + * A struct for workqueue attributes. This can be used to change + * attributes of an unbound workqueue. + * + * Unlike other fields, ->no_numa isn't a property of a worker_pool. It + * only modifies how apply_workqueue_attrs() select pools and thus doesn't + * participate in pool hash calculations or equality comparisons. + */ +struct workqueue_attrs { + int nice; /* nice level */ + cpumask_var_t cpumask; /* allowed CPUs */ + bool no_numa; /* disable NUMA affinity */ +}; + static inline struct delayed_work *to_delayed_work(struct work_struct *work) { return container_of(work, struct delayed_work, work); @@ -277,15 +295,48 @@ static inline unsigned int work_static(struct work_struct *work) { return 0; } * Documentation/workqueue.txt. */ enum { - WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */ + /* + * All wqs are now non-reentrant making the following flag + * meaningless. Will be removed. + */ + WQ_NON_REENTRANT = 1 << 0, /* DEPRECATED */ + 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 instensive workqueue */ + WQ_SYSFS = 1 << 6, /* visible in sysfs, see wq_sysfs_register() */ - WQ_DRAINING = 1 << 6, /* internal: workqueue is draining */ - WQ_RESCUER = 1 << 7, /* internal: workqueue has rescuer */ + /* + * 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 + * excute 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_MAX_ACTIVE = 512, /* I like 512, better ideas? */ WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */ @@ -314,11 +365,19 @@ enum { * * 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_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; static inline struct workqueue_struct * __deprecated __system_nrt_wq(void) { @@ -388,41 +447,35 @@ __alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active, * Pointer to the allocated workqueue on success, %NULL on failure. */ #define alloc_ordered_workqueue(fmt, flags, args...) \ - alloc_workqueue(fmt, WQ_UNBOUND | (flags), 1, ##args) + alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | (flags), 1, ##args) #define create_workqueue(name) \ - alloc_workqueue((name), WQ_MEM_RECLAIM, 1) + alloc_workqueue("%s", WQ_MEM_RECLAIM, 1, (name)) #define create_freezable_workqueue(name) \ - alloc_workqueue((name), WQ_FREEZABLE | WQ_UNBOUND | WQ_MEM_RECLAIM, 1) + alloc_workqueue("%s", WQ_FREEZABLE | WQ_UNBOUND | WQ_MEM_RECLAIM, \ + 1, (name)) #define create_singlethread_workqueue(name) \ - alloc_workqueue((name), WQ_UNBOUND | WQ_MEM_RECLAIM, 1) + alloc_workqueue("%s", WQ_UNBOUND | WQ_MEM_RECLAIM, 1, (name)) extern void destroy_workqueue(struct workqueue_struct *wq); +struct workqueue_attrs *alloc_workqueue_attrs(gfp_t gfp_mask); +void free_workqueue_attrs(struct workqueue_attrs *attrs); +int apply_workqueue_attrs(struct workqueue_struct *wq, + const struct workqueue_attrs *attrs); + extern bool queue_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work); -extern bool queue_work(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 queue_delayed_work(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 mod_delayed_work(struct workqueue_struct *wq, - struct delayed_work *dwork, unsigned long delay); extern void flush_workqueue(struct workqueue_struct *wq); extern void drain_workqueue(struct workqueue_struct *wq); extern void flush_scheduled_work(void); -extern bool schedule_work_on(int cpu, struct work_struct *work); -extern bool schedule_work(struct work_struct *work); -extern bool schedule_delayed_work_on(int cpu, struct delayed_work *work, - unsigned long delay); -extern bool schedule_delayed_work(struct delayed_work *work, - unsigned long delay); extern int schedule_on_each_cpu(work_func_t func); -extern int keventd_up(void); int execute_in_process_context(work_func_t fn, struct execute_work *); @@ -435,8 +488,122 @@ extern bool cancel_delayed_work_sync(struct delayed_work *dwork); extern void workqueue_set_max_active(struct workqueue_struct *wq, int max_active); -extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq); +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); + +/** + * 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. + */ +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. + */ +static inline bool schedule_work(struct work_struct *work) +{ + return queue_work(system_wq, work); +} + +/** + * 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); +} + +/** + * keventd_up - is workqueue initialized yet? + */ +static inline bool keventd_up(void) +{ + return system_wq != NULL; +} /* * Like above, but uses del_timer() instead of del_timer_sync(). This means, @@ -466,12 +633,12 @@ static inline bool __deprecated flush_delayed_work_sync(struct delayed_work *dwo } #ifndef CONFIG_SMP -static inline long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg) +static inline long work_on_cpu(int cpu, long (*fn)(void *), void *arg) { return fn(arg); } #else -long work_on_cpu(unsigned int cpu, long (*fn)(void *), void *arg); +long work_on_cpu(int cpu, long (*fn)(void *), void *arg); #endif /* CONFIG_SMP */ #ifdef CONFIG_FREEZER @@ -480,4 +647,11 @@ 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 */ + #endif |