kernel/workqueue_internal.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * kernel/workqueue_internal.h
   4  *
   5  * Workqueue internal header file.  Only to be included by workqueue and
   6  * core kernel subsystems.
   7  */
   8 #ifndef _KERNEL_WORKQUEUE_INTERNAL_H
   9 #define _KERNEL_WORKQUEUE_INTERNAL_H
  10
  11 #include <linux/workqueue.h>
  12 #include <linux/kthread.h>
  13 #include <linux/preempt.h>
  14
  15 struct worker_pool;
  16
  17 /*
  18  * The poor guys doing the actual heavy lifting.  All on-duty workers are
  19  * either serving the manager role, on idle list or on busy hash.  For
  20  * details on the locking annotation (L, I, X...), refer to workqueue.c.
  21  *
  22  * Only to be used in workqueue and async.
  23  */
  24 struct worker {
  25         /* on idle list while idle, on busy hash table while busy */
  26         union {
  27                 struct list_head        entry;  /* L: while idle */
  28                 struct hlist_node       hentry; /* L: while busy */
  29         };
  30
  31         struct work_struct      *current_work;  /* L: work being processed */
  32         work_func_t             current_func;   /* L: current_work's fn */
  33         struct pool_workqueue   *current_pwq; /* L: current_work's pwq */
  34         struct list_head        scheduled;      /* L: scheduled works */
  35
  36         /* 64 bytes boundary on 64bit, 32 on 32bit */
  37
  38         struct task_struct      *task;          /* I: worker task */
  39         struct worker_pool      *pool;          /* A: the associated pool */
  40                                                 /* L: for rescuers */
  41         struct list_head        node;           /* A: anchored at pool->workers */
  42                                                 /* A: runs through worker->node */
  43
  44         unsigned long           last_active;    /* L: last active timestamp */
  45         unsigned int            flags;          /* X: flags */
  46         int                     id;             /* I: worker id */
  47
  48         /*
  49          * Opaque string set with work_set_desc().  Printed out with task
  50          * dump for debugging - WARN, BUG, panic or sysrq.
  51          */
  52         char                    desc[WORKER_DESC_LEN];
  53
  54         /* used only by rescuers to point to the target workqueue */
  55         struct workqueue_struct *rescue_wq;     /* I: the workqueue to rescue */
  56
  57         /* used by the scheduler to determine a worker's last known identity */
  58         work_func_t             last_func;
  59 };
  60
  61 /**
  62  * current_wq_worker - return struct worker if %current is a workqueue worker
  63  */
  64 static inline struct worker *current_wq_worker(void)
  65 {
  66         if (in_task() && (current->flags & PF_WQ_WORKER))
  67                 return kthread_data(current);
  68         return NULL;
  69 }
  70
  71 /*
  72  * Scheduler hooks for concurrency managed workqueue.  Only to be used from
  73  * sched/ and workqueue.c.
  74  */
  75 void wq_worker_waking_up(struct task_struct *task, int cpu);
  76 struct task_struct *wq_worker_sleeping(struct task_struct *task);
  77 work_func_t wq_worker_last_func(struct task_struct *task);
  78
  79 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */