LXR linux/kernel/workqueue

   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
  15struct 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 */
  24struct 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        unsigned int            current_color;  /* L: current_work's color */
  35        struct list_head        scheduled;      /* L: scheduled works */
  36
  37        /* 64 bytes boundary on 64bit, 32 on 32bit */
  38
  39        struct task_struct      *task;          /* I: worker task */
  40        struct worker_pool      *pool;          /* A: the associated pool */
  41                                                /* L: for rescuers */
  42        struct list_head        node;           /* A: anchored at pool->workers */
  43                                                /* A: runs through worker->node */
  44
  45        unsigned long           last_active;    /* L: last active timestamp */
  46        unsigned int            flags;          /* X: flags */
  47        int                     id;             /* I: worker id */
  48        int                     sleeping;       /* None */
  49
  50        /*
  51         * Opaque string set with work_set_desc().  Printed out with task
  52         * dump for debugging - WARN, BUG, panic or sysrq.
  53         */
  54        char                    desc[WORKER_DESC_LEN];
  55
  56        /* used only by rescuers to point to the target workqueue */
  57        struct workqueue_struct *rescue_wq;     /* I: the workqueue to rescue */
  58
  59        /* used by the scheduler to determine a worker's last known identity */
  60        work_func_t             last_func;
  61};
  62
  63/**
  64 * current_wq_worker - return struct worker if %current is a workqueue worker
  65 */
  66static inline struct worker *current_wq_worker(void)
  67{
  68        if (in_task() && (current->flags & PF_WQ_WORKER))
  69                return kthread_data(current);
  70        return NULL;
  71}
  72
  73/*
  74 * Scheduler hooks for concurrency managed workqueue.  Only to be used from
  75 * sched/ and workqueue.c.
  76 */
  77void wq_worker_running(struct task_struct *task);
  78void wq_worker_sleeping(struct task_struct *task);
  79work_func_t wq_worker_last_func(struct task_struct *task);
  80
  81#endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
  82