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;  /* K: work being processed and its */
  32         work_func_t             current_func;   /* K: function */
  33         struct pool_workqueue   *current_pwq;   /* K: pwq */
  34         u64                     current_at;     /* K: runtime at start or last wakeup */
  35         unsigned int            current_color;  /* K: color */
  36
  37         int                     sleeping;       /* S: is worker sleeping? */
  38
  39         /* used by the scheduler to determine a worker's last known identity */
  40         work_func_t             last_func;      /* K: last work's fn */
  41
  42         struct list_head        scheduled;      /* L: scheduled works */
  43
  44         struct task_struct      *task;          /* I: worker task */
  45         struct worker_pool      *pool;          /* A: the associated pool */
  46                                                 /* L: for rescuers */
  47         struct list_head        node;           /* A: anchored at pool->workers */
  48                                                 /* A: runs through worker->node */
  49
  50         unsigned long           last_active;    /* K: last active timestamp */
  51         unsigned int            flags;          /* L: flags */
  52         int                     id;             /* I: worker id */
  53
  54         /*
  55          * Opaque string set with work_set_desc().  Printed out with task
  56          * dump for debugging - WARN, BUG, panic or sysrq.
  57          */
  58         char                    desc[WORKER_DESC_LEN];
  59
  60         /* used only by rescuers to point to the target workqueue */
  61         struct workqueue_struct *rescue_wq;     /* I: the workqueue to rescue */
  62 };
  63
  64 /**
  65  * current_wq_worker - return struct worker if %current is a workqueue worker
  66  */
  67 static inline struct worker *current_wq_worker(void)
  68 {
  69         if (in_task() && (current->flags & PF_WQ_WORKER))
  70                 return kthread_data(current);
  71         return NULL;
  72 }
  73
  74 /*
  75  * Scheduler hooks for concurrency managed workqueue.  Only to be used from
  76  * sched/ and workqueue.c.
  77  */
  78 void wq_worker_running(struct task_struct *task);
  79 void wq_worker_sleeping(struct task_struct *task);
  80 void wq_worker_tick(struct task_struct *task);
  81 work_func_t wq_worker_last_func(struct task_struct *task);
  82
  83 #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */