libcfs/include/libcfs/libcfs_prim.h

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 /*
  31  * This file is part of Lustre, http://www.lustre.org/
  32  * Lustre is a trademark of Sun Microsystems, Inc.
  33  *
  34  * libcfs/include/libcfs/libcfs_prim.h
  35  *
  36  * General primitives.
  37  *
  38  */
  39
  40 #ifndef __LIBCFS_PRIM_H__
  41 #define __LIBCFS_PRIM_H__
  42
  43 #ifndef CFS_EXPORT_SYMBOL
  44 # define CFS_EXPORT_SYMBOL(s)
  45 #endif
  46
  47 /*
  48  * Schedule
  49  */
  50 void cfs_schedule_timeout_and_set_state(cfs_task_state_t state,
  51                                         int64_t timeout);
  52 void cfs_schedule_timeout(int64_t timeout);
  53 void cfs_schedule(void);
  54 void cfs_pause(cfs_duration_t ticks);
  55 int  cfs_need_resched(void);
  56 void cfs_cond_resched(void);
  57
  58 /*
  59  * Wait Queues
  60  */
  61 void cfs_waitq_init(cfs_waitq_t *waitq);
  62 void cfs_waitlink_init(cfs_waitlink_t *link);
  63 void cfs_waitq_add(cfs_waitq_t *waitq, cfs_waitlink_t *link);
  64 void cfs_waitq_add_exclusive(cfs_waitq_t *waitq,
  65                              cfs_waitlink_t *link);
  66 void cfs_waitq_add_exclusive_head(cfs_waitq_t *waitq,
  67                                   cfs_waitlink_t *link);
  68 void cfs_waitq_del(cfs_waitq_t *waitq, cfs_waitlink_t *link);
  69 int  cfs_waitq_active(cfs_waitq_t *waitq);
  70 void cfs_waitq_signal(cfs_waitq_t *waitq);
  71 void cfs_waitq_signal_nr(cfs_waitq_t *waitq, int nr);
  72 void cfs_waitq_broadcast(cfs_waitq_t *waitq);
  73 void cfs_waitq_wait(cfs_waitlink_t *link, cfs_task_state_t state);
  74 int64_t cfs_waitq_timedwait(cfs_waitlink_t *link, cfs_task_state_t state,
  75                             int64_t timeout);
  76
  77 /*
  78  * Timer
  79  */
  80 typedef  void (cfs_timer_func_t)(ulong_ptr_t);
  81
  82 void cfs_init_timer(cfs_timer_t *t);
  83 void cfs_timer_init(cfs_timer_t *t, cfs_timer_func_t *func, void *arg);
  84 void cfs_timer_done(cfs_timer_t *t);
  85 void cfs_timer_arm(cfs_timer_t *t, cfs_time_t deadline);
  86 void cfs_timer_disarm(cfs_timer_t *t);
  87 int  cfs_timer_is_armed(cfs_timer_t *t);
  88 cfs_time_t cfs_timer_deadline(cfs_timer_t *t);
  89
  90 /*
  91  * Memory
  92  */
  93 #ifndef cfs_memory_pressure_get
  94 #define cfs_memory_pressure_get() (0)
  95 #endif
  96 #ifndef cfs_memory_pressure_set
  97 #define cfs_memory_pressure_set() do {} while (0)
  98 #endif
  99 #ifndef cfs_memory_pressure_clr
 100 #define cfs_memory_pressure_clr() do {} while (0)
 101 #endif
 102
 103 static inline int cfs_memory_pressure_get_and_set(void)
 104 {
 105         int old = cfs_memory_pressure_get();
 106
 107         if (!old)
 108                 cfs_memory_pressure_set();
 109         return old;
 110 }
 111
 112 static inline void cfs_memory_pressure_restore(int old)
 113 {
 114         if (old)
 115                 cfs_memory_pressure_set();
 116         else
 117                 cfs_memory_pressure_clr();
 118         return;
 119 }
 120 #endif