nptl/sysdeps/unix/sysv/linux/sparc/lowlevellock.h

   1 /* Copyright (C) 2003, 2004, 2006 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Jakub Jelinek <jakub@redhat.com>, 2003.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Libr    \ary; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _LOWLEVELLOCK_H
  21 #define _LOWLEVELLOCK_H 1
  22
  23 #include <time.h>
  24 #include <sys/param.h>
  25 #include <bits/pthreadtypes.h>
  26 #include <atomic.h>
  27
  28
  29 #define FUTEX_WAIT              0
  30 #define FUTEX_WAKE              1
  31 #define FUTEX_REQUEUE           3
  32 #define FUTEX_CMP_REQUEUE       4
  33 #define FUTEX_WAKE_OP           5
  34 #define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE   ((4 << 24) | 1)
  35
  36 /* Initializer for compatibility lock.  */
  37 #define LLL_MUTEX_LOCK_INITIALIZER (0)
  38
  39 #define lll_futex_wait(futexp, val) \
  40   ({                                                                          \
  41     INTERNAL_SYSCALL_DECL (__err);                                            \
  42     long int __ret;                                                           \
  43                                                                               \
  44     __ret = INTERNAL_SYSCALL (futex, __err, 4,                                \
  45                               (futexp), FUTEX_WAIT, (val), 0);                \
  46     __ret;                                                                    \
  47   })
  48
  49 #define lll_futex_timed_wait(futexp, val, timespec) \
  50   ({                                                                          \
  51     INTERNAL_SYSCALL_DECL (__err);                                            \
  52     long int __ret;                                                           \
  53                                                                               \
  54     __ret = INTERNAL_SYSCALL (futex, __err, 4,                                \
  55                               (futexp), FUTEX_WAIT, (val), (timespec));       \
  56     __ret;                                                                    \
  57   })
  58
  59 #define lll_futex_wake(futexp, nr) \
  60   ({                                                                          \
  61     INTERNAL_SYSCALL_DECL (__err);                                            \
  62     long int __ret;                                                           \
  63                                                                               \
  64     __ret = INTERNAL_SYSCALL (futex, __err, 4,                                \
  65                               (futexp), FUTEX_WAKE, (nr), 0);                 \
  66     __ret;                                                                    \
  67   })
  68
  69 /* Returns non-zero if error happened, zero if success.  */
  70 #define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val) \
  71   ({                                                                          \
  72     INTERNAL_SYSCALL_DECL (__err);                                            \
  73     long int __ret;                                                           \
  74                                                                               \
  75     __ret = INTERNAL_SYSCALL (futex, __err, 6,                                \
  76                               (futexp), FUTEX_CMP_REQUEUE, (nr_wake),         \
  77                               (nr_move), (mutex), (val));                     \
  78     INTERNAL_SYSCALL_ERROR_P (__ret, __err);                                  \
  79   })
  80
  81 #define lll_robust_mutex_dead(futexv) \
  82   do                                                                          \
  83     {                                                                         \
  84       int *__futexp = &(futexv);                                              \
  85       atomic_or (__futexp, FUTEX_OWNER_DIED);                                 \
  86       lll_futex_wake (__futexp, 1);                                           \
  87     }                                                                         \
  88   while (0)
  89
  90 /* Returns non-zero if error happened, zero if success.  */
  91 #ifdef __sparc32_atomic_do_lock
  92 /* Avoid FUTEX_WAKE_OP if supporting pre-v9 CPUs.  */
  93 # define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) 1
  94 #else
  95 # define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) \
  96   ({                                                                          \
  97     INTERNAL_SYSCALL_DECL (__err);                                            \
  98     long int __ret;                                                           \
  99                                                                               \
 100     __ret = INTERNAL_SYSCALL (futex, __err, 6,                                \
 101                               (futexp), FUTEX_WAKE_OP, (nr_wake),             \
 102                               (nr_wake2), (futexp2),                          \
 103                               FUTEX_OP_CLEAR_WAKE_IF_GT_ONE);                 \
 104     INTERNAL_SYSCALL_ERROR_P (__ret, __err);                                  \
 105   })
 106 #endif
 107
 108 static inline int
 109 __attribute__ ((always_inline))
 110 __lll_mutex_trylock (int *futex)
 111 {
 112   return atomic_compare_and_exchange_val_24_acq (futex, 1, 0) != 0;
 113 }
 114 #define lll_mutex_trylock(futex) __lll_mutex_trylock (&(futex))
 115
 116 static inline int
 117 __attribute__ ((always_inline))
 118 __lll_mutex_cond_trylock (int *futex)
 119 {
 120   return atomic_compare_and_exchange_val_24_acq (futex, 2, 0) != 0;
 121 }
 122 #define lll_mutex_cond_trylock(futex) __lll_mutex_cond_trylock (&(futex))
 123
 124 static inline int
 125 __attribute__ ((always_inline))
 126 __lll_robust_mutex_trylock (int *futex, int id)
 127 {
 128   return atomic_compare_and_exchange_val_acq (futex, id, 0) != 0;
 129 }
 130 #define lll_robust_mutex_trylock(futex, id) \
 131   __lll_robust_mutex_trylock (&(futex), id)
 132
 133
 134 extern void __lll_lock_wait (int *futex) attribute_hidden;
 135 extern int __lll_robust_lock_wait (int *futex) attribute_hidden;
 136
 137 static inline void
 138 __attribute__ ((always_inline))
 139 __lll_mutex_lock (int *futex)
 140 {
 141   int val = atomic_compare_and_exchange_val_24_acq (futex, 1, 0);
 142
 143   if (__builtin_expect (val != 0, 0))
 144     __lll_lock_wait (futex);
 145 }
 146 #define lll_mutex_lock(futex) __lll_mutex_lock (&(futex))
 147
 148 static inline int
 149 __attribute__ ((always_inline))
 150 __lll_robust_mutex_lock (int *futex, int id)
 151 {
 152   int result = 0;
 153   if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
 154     result = __lll_robust_lock_wait (futex);
 155   return result;
 156 }
 157 #define lll_robust_mutex_lock(futex, id) \
 158   __lll_robust_mutex_lock (&(futex), id)
 159
 160 static inline void
 161 __attribute__ ((always_inline))
 162 __lll_mutex_cond_lock (int *futex)
 163 {
 164   int val = atomic_compare_and_exchange_val_24_acq (futex, 2, 0);
 165
 166   if (__builtin_expect (val != 0, 0))
 167     __lll_lock_wait (futex);
 168 }
 169 #define lll_mutex_cond_lock(futex) __lll_mutex_cond_lock (&(futex))
 170
 171 #define lll_robust_mutex_cond_lock(futex, id) \
 172   __lll_robust_mutex_lock (&(futex), (id) | FUTEX_WAITERS)
 173
 174
 175 extern int __lll_timedlock_wait (int *futex, const struct timespec *)
 176      attribute_hidden;
 177 extern int __lll_robust_timedlock_wait (int *futex, const struct timespec *)
 178      attribute_hidden;
 179
 180 static inline int
 181 __attribute__ ((always_inline))
 182 __lll_mutex_timedlock (int *futex, const struct timespec *abstime)
 183 {
 184   int val = atomic_compare_and_exchange_val_24_acq (futex, 1, 0);
 185   int result = 0;
 186
 187   if (__builtin_expect (val != 0, 0))
 188     result = __lll_timedlock_wait (futex, abstime);
 189   return result;
 190 }
 191 #define lll_mutex_timedlock(futex, abstime) \
 192   __lll_mutex_timedlock (&(futex), abstime)
 193
 194 static inline int
 195 __attribute__ ((always_inline))
 196 __lll_robust_mutex_timedlock (int *futex, const struct timespec *abstime,
 197                               int id)
 198 {
 199   int result = 0;
 200   if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
 201     result = __lll_robust_timedlock_wait (futex, abstime);
 202   return result;
 203 }
 204 #define lll_robust_mutex_timedlock(futex, abstime, id) \
 205   __lll_robust_mutex_timedlock (&(futex), abstime, id)
 206
 207 #define lll_mutex_unlock(lock) \
 208   ((void) ({                                                                  \
 209     int *__futex = &(lock);                                                   \
 210     int __val = atomic_exchange_24_rel (__futex, 0);                          \
 211     if (__builtin_expect (__val > 1, 0))                                      \
 212       lll_futex_wake (__futex, 1);                                            \
 213   }))
 214
 215 #define lll_robust_mutex_unlock(lock) \
 216   ((void) ({                                                                  \
 217     int *__futex = &(lock);                                                   \
 218     int __val = atomic_exchange_rel (__futex, 0);                             \
 219     if (__builtin_expect (__val & FUTEX_WAITERS, 0))                          \
 220       lll_futex_wake (__futex, 1);                                            \
 221   }))
 222
 223 #define lll_mutex_unlock_force(lock) \
 224   ((void) ({                                                                  \
 225     int *__futex = &(lock);                                                   \
 226     (void) atomic_exchange_24_rel (__futex, 0);                               \
 227     lll_futex_wake (__futex, 1);                                              \
 228   }))
 229
 230 #define lll_mutex_islocked(futex) \
 231   (futex != 0)
 232
 233
 234 /* We have a separate internal lock implementation which is not tied
 235    to binary compatibility.  We can use the lll_mutex_*.  */
 236
 237 /* Type for lock object.  */
 238 typedef int lll_lock_t;
 239
 240 extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
 241
 242 /* Initializers for lock.  */
 243 #define LLL_LOCK_INITIALIZER            (0)
 244 #define LLL_LOCK_INITIALIZER_LOCKED     (1)
 245
 246 #define lll_trylock(futex)      lll_mutex_trylock (futex)
 247 #define lll_lock(futex)         lll_mutex_lock (futex)
 248 #define lll_unlock(futex)       lll_mutex_unlock (futex)
 249 #define lll_islocked(futex)     lll_mutex_islocked (futex)
 250
 251
 252 /* The kernel notifies a process with uses CLONE_CLEARTID via futex
 253    wakeup when the clone terminates.  The memory location contains the
 254    thread ID while the clone is running and is reset to zero
 255    afterwards.  */
 256 #define lll_wait_tid(tid) \
 257   do                                            \
 258     {                                           \
 259       __typeof (tid) __tid;                     \
 260       while ((__tid = (tid)) != 0)              \
 261         lll_futex_wait (&(tid), __tid);         \
 262     }                                           \
 263   while (0)
 264
 265 extern int __lll_timedwait_tid (int *, const struct timespec *)
 266      attribute_hidden;
 267
 268 #define lll_timedwait_tid(tid, abstime) \
 269   ({                                                    \
 270     int __res = 0;                                      \
 271     if ((tid) != 0)                                     \
 272       __res = __lll_timedwait_tid (&(tid), (abstime));  \
 273     __res;                                              \
 274   })
 275
 276
 277 /* Conditional variable handling.  */
 278
 279 extern void __lll_cond_wait (pthread_cond_t *cond)
 280      attribute_hidden;
 281 extern int __lll_cond_timedwait (pthread_cond_t *cond,
 282                                  const struct timespec *abstime)
 283      attribute_hidden;
 284 extern void __lll_cond_wake (pthread_cond_t *cond)
 285      attribute_hidden;
 286 extern void __lll_cond_broadcast (pthread_cond_t *cond)
 287      attribute_hidden;
 288
 289 #define lll_cond_wait(cond) \
 290   __lll_cond_wait (cond)
 291 #define lll_cond_timedwait(cond, abstime) \
 292   __lll_cond_timedwait (cond, abstime)
 293 #define lll_cond_wake(cond) \
 294   __lll_cond_wake (cond)
 295 #define lll_cond_broadcast(cond) \
 296   __lll_cond_broadcast (cond)
 297
 298 #endif  /* lowlevellock.h */