kernel/slow-work.h

   1 /* Slow work private definitions
   2  *
   3  * Copyright (C) 2009 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 #define SLOW_WORK_CULL_TIMEOUT (5 * HZ) /* cull threads 5s after running out of
  13                                          * things to do */
  14 #define SLOW_WORK_OOM_TIMEOUT (5 * HZ)  /* can't start new threads for 5s after
  15                                          * OOM */
  16
  17 #define SLOW_WORK_THREAD_LIMIT  255     /* abs maximum number of slow-work threads */
  18
  19 /*
  20  * slow-work.c
  21  */
  22 #ifdef CONFIG_SLOW_WORK_DEBUG
  23 extern struct slow_work *slow_work_execs[];
  24 extern pid_t slow_work_pids[];
  25 extern rwlock_t slow_work_execs_lock;
  26 #endif
  27
  28 extern struct list_head slow_work_queue;
  29 extern struct list_head vslow_work_queue;
  30 extern spinlock_t slow_work_queue_lock;
  31
  32 /*
  33  * slow-work-debugfs.c
  34  */
  35 #ifdef CONFIG_SLOW_WORK_DEBUG
  36 extern const struct file_operations slow_work_runqueue_fops;
  37
  38 extern void slow_work_new_thread_desc(struct slow_work *, struct seq_file *);
  39 #endif
  40
  41 /*
  42  * Helper functions
  43  */
  44 static inline void slow_work_set_thread_pid(int id, pid_t pid)
  45 {
  46 #ifdef CONFIG_SLOW_WORK_DEBUG
  47         slow_work_pids[id] = pid;
  48 #endif
  49 }
  50
  51 static inline void slow_work_mark_time(struct slow_work *work)
  52 {
  53 #ifdef CONFIG_SLOW_WORK_DEBUG
  54         work->mark = CURRENT_TIME;
  55 #endif
  56 }
  57
  58 static inline void slow_work_begin_exec(int id, struct slow_work *work)
  59 {
  60 #ifdef CONFIG_SLOW_WORK_DEBUG
  61         slow_work_execs[id] = work;
  62 #endif
  63 }
  64
  65 static inline void slow_work_end_exec(int id, struct slow_work *work)
  66 {
  67 #ifdef CONFIG_SLOW_WORK_DEBUG
  68         write_lock(&slow_work_execs_lock);
  69         slow_work_execs[id] = NULL;
  70         write_unlock(&slow_work_execs_lock);
  71 #endif
  72 }