include/sys/mutex.h

   1 /*
   2  *  This file is part of the SPL: Solaris Porting Layer.
   3  *
   4  *  Copyright (c) 2008 Lawrence Livermore National Security, LLC.
   5  *  Produced at Lawrence Livermore National Laboratory
   6  *  Written by:
   7  *          Brian Behlendorf <behlendorf1@llnl.gov>,
   8  *          Herb Wartens <wartens2@llnl.gov>,
   9  *          Jim Garlick <garlick@llnl.gov>
  10  *  UCRL-CODE-235197
  11  *
  12  *  This is free software; you can redistribute it and/or modify it
  13  *  under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or
  15  *  (at your option) any later version.
  16  *
  17  *  This is distributed in the hope that it will be useful, but WITHOUT
  18  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  *  for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
  25  */
  26
  27 #ifndef _SPL_MUTEX_H
  28 #define _SPL_MUTEX_H
  29
  30 #ifdef  __cplusplus
  31 extern "C" {
  32 #endif
  33
  34 #include <linux/module.h>
  35 #include <linux/hardirq.h>
  36 #include <sys/types.h>
  37 #include <sys/kmem.h>
  38
  39 #define MUTEX_DEFAULT           0
  40 #define MUTEX_SPIN              1
  41 #define MUTEX_ADAPTIVE          2
  42
  43 #define MUTEX_ENTER_TOTAL       0
  44 #define MUTEX_ENTER_NOT_HELD    1
  45 #define MUTEX_ENTER_SPIN        2
  46 #define MUTEX_ENTER_SLEEP       3
  47 #define MUTEX_TRYENTER_TOTAL    4
  48 #define MUTEX_TRYENTER_NOT_HELD 5
  49 #define MUTEX_STATS_SIZE        6
  50
  51 #define KM_MAGIC                0x42424242
  52 #define KM_POISON               0x84
  53
  54 typedef struct {
  55         int32_t km_magic;
  56         int16_t km_type;
  57         int16_t km_name_size;
  58         char *km_name;
  59         struct task_struct *km_owner;
  60         struct semaphore *km_sem;
  61 #ifdef DEBUG_MUTEX
  62         int *km_stats;
  63         struct list_head km_list;
  64 #endif
  65 } kmutex_t;
  66
  67 extern int mutex_spin_max;
  68
  69 #ifdef DEBUG_MUTEX
  70 extern int mutex_stats[MUTEX_STATS_SIZE];
  71 extern spinlock_t mutex_stats_lock;
  72 extern struct list_head mutex_stats_list;
  73 #define MUTEX_STAT_INC(stats, stat)     ((stats)[stat]++)
  74 #else
  75 #define MUTEX_STAT_INC(stats, stat)
  76 #endif
  77
  78 int spl_mutex_init(void);
  79 void spl_mutex_fini(void);
  80
  81 extern int __spl_mutex_init(kmutex_t *mp, char *name, int type, void *ibc);
  82 extern void __spl_mutex_destroy(kmutex_t *mp);
  83 extern int __mutex_tryenter(kmutex_t *mp);
  84 extern void __mutex_enter(kmutex_t *mp);
  85 extern void __mutex_exit(kmutex_t *mp);
  86 extern int __mutex_owned(kmutex_t *mp);
  87 extern kthread_t *__spl_mutex_owner(kmutex_t *mp);
  88
  89 #undef mutex_init
  90 #undef mutex_destroy
  91
  92 #define mutex_init(mp, name, type, ibc)                                 \
  93 ({                                                                      \
  94         /* May never fail or all subsequent mutex_* calls will ASSERT */\
  95         if ((name) == NULL)                                             \
  96                 while(__spl_mutex_init(mp, #mp, type, ibc));            \
  97         else                                                            \
  98                 while(__spl_mutex_init(mp, name, type, ibc));           \
  99 })
 100 #define mutex_destroy(mp)       __spl_mutex_destroy(mp)
 101 #define mutex_tryenter(mp)      __mutex_tryenter(mp)
 102 #define mutex_enter(mp)         __mutex_enter(mp)
 103 #define mutex_exit(mp)          __mutex_exit(mp)
 104 #define mutex_owned(mp)         __mutex_owned(mp)
 105 #define mutex_owner(mp)         __spl_mutex_owner(mp)
 106 #define MUTEX_HELD(mp)          mutex_owned(mp)
 107
 108 #ifdef  __cplusplus
 109 }
 110 #endif
 111
 112 #endif  /* _SPL_MUTEX_H */