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

   1 /* Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   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 Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _LOWLEVELLOCK_H
  20 #define _LOWLEVELLOCK_H 1
  21
  22 #ifndef __ASSEMBLER__
  23 #include <time.h>
  24 #include <sys/param.h>
  25 #include <bits/pthreadtypes.h>
  26 #include <kernel-features.h>
  27 #endif
  28
  29 #define SYS_futex               240
  30 #define FUTEX_WAIT              0
  31 #define FUTEX_WAKE              1
  32 #define FUTEX_CMP_REQUEUE       4
  33 #define FUTEX_WAKE_OP           5
  34 #define FUTEX_LOCK_PI           6
  35 #define FUTEX_UNLOCK_PI         7
  36 #define FUTEX_TRYLOCK_PI        8
  37 #define FUTEX_WAIT_BITSET       9
  38 #define FUTEX_WAKE_BITSET       10
  39 #define FUTEX_PRIVATE_FLAG      128
  40 #define FUTEX_CLOCK_REALTIME    256
  41
  42 #define FUTEX_BITSET_MATCH_ANY  0xffffffff
  43
  44 #define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE   ((4 << 24) | 1)
  45
  46 /* Values for 'private' parameter of locking macros.  Yes, the
  47    definition seems to be backwards.  But it is not.  The bit will be
  48    reversed before passing to the system call.  */
  49 #define LLL_PRIVATE    0
  50 #define LLL_SHARED     FUTEX_PRIVATE_FLAG
  51
  52
  53 #if !defined NOT_IN_libc || defined IS_IN_rtld
  54 /* In libc.so or ld.so all futexes are private.  */
  55 # ifdef __ASSUME_PRIVATE_FUTEX
  56 #  define __lll_private_flag(fl, private) \
  57   ((fl) | FUTEX_PRIVATE_FLAG)
  58 # else
  59 #  define __lll_private_flag(fl, private) \
  60   ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))
  61 # endif
  62 #else
  63 # ifdef __ASSUME_PRIVATE_FUTEX
  64 #  define __lll_private_flag(fl, private) \
  65   (((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
  66 # else
  67 #  define __lll_private_flag(fl, private) \
  68   (__builtin_constant_p (private)                                             \
  69    ? ((private) == 0                                                          \
  70       ? ((fl) | THREAD_GETMEM (THREAD_SELF, header.private_futex))            \
  71       : (fl))                                                                 \
  72    : ((fl) | (((private) ^ FUTEX_PRIVATE_FLAG)                                \
  73               & THREAD_GETMEM (THREAD_SELF, header.private_futex))))
  74 # endif
  75 #endif
  76
  77 #ifndef __ASSEMBLER__
  78
  79 /* Initializer for compatibility lock.  */
  80 #define LLL_LOCK_INITIALIZER            (0)
  81 #define LLL_LOCK_INITIALIZER_LOCKED     (1)
  82 #define LLL_LOCK_INITIALIZER_WAITERS    (2)
  83
  84 extern int __lll_lock_wait_private (int val, int *__futex)
  85   attribute_hidden;
  86 extern int __lll_lock_wait (int val, int *__futex, int private)
  87   attribute_hidden;
  88 extern int __lll_timedlock_wait (int val, int *__futex,
  89                                  const struct timespec *abstime, int private)
  90   attribute_hidden;
  91 extern int __lll_robust_lock_wait (int val, int *__futex, int private)
  92   attribute_hidden;
  93 extern int __lll_robust_timedlock_wait (int val, int *__futex,
  94                                         const struct timespec *abstime,
  95                                         int private)
  96   attribute_hidden;
  97 extern int __lll_unlock_wake_private (int *__futex) attribute_hidden;
  98 extern int __lll_unlock_wake (int *__futex, int private) attribute_hidden;
  99
 100 #define lll_trylock(futex) \
 101   ({ unsigned char __result; \
 102      __asm __volatile ("\
 103         .align 2\n\
 104         mova 1f,r0\n\
 105         nop\n\
 106         mov r15,r1\n\
 107         mov #-8,r15\n\
 108      0: mov.l @%1,r2\n\
 109         cmp/eq r2,%3\n\
 110         bf 1f\n\
 111         mov.l %2,@%1\n\
 112      1: mov r1,r15\n\
 113         mov #-1,%0\n\
 114         negc %0,%0"\
 115         : "=r" (__result) \
 116         : "r" (&(futex)), \
 117           "r" (LLL_LOCK_INITIALIZER_LOCKED), \
 118           "r" (LLL_LOCK_INITIALIZER) \
 119         : "r0", "r1", "r2", "t", "memory"); \
 120      __result; })
 121
 122 #define lll_robust_trylock(futex, id)   \
 123   ({ unsigned char __result; \
 124      __asm __volatile ("\
 125         .align 2\n\
 126         mova 1f,r0\n\
 127         nop\n\
 128         mov r15,r1\n\
 129         mov #-8,r15\n\
 130      0: mov.l @%1,r2\n\
 131         cmp/eq r2,%3\n\
 132         bf 1f\n\
 133         mov.l %2,@%1\n\
 134      1: mov r1,r15\n\
 135         mov #-1,%0\n\
 136         negc %0,%0"\
 137         : "=r" (__result) \
 138         : "r" (&(futex)), \
 139           "r" (id), \
 140           "r" (LLL_LOCK_INITIALIZER) \
 141         : "r0", "r1", "r2", "t", "memory"); \
 142      __result; })
 143
 144 #define lll_cond_trylock(futex) \
 145   ({ unsigned char __result; \
 146      __asm __volatile ("\
 147         .align 2\n\
 148         mova 1f,r0\n\
 149         nop\n\
 150         mov r15,r1\n\
 151         mov #-8,r15\n\
 152      0: mov.l @%1,r2\n\
 153         cmp/eq r2,%3\n\
 154         bf 1f\n\
 155         mov.l %2,@%1\n\
 156      1: mov r1,r15\n\
 157         mov #-1,%0\n\
 158         negc %0,%0"\
 159         : "=r" (__result) \
 160         : "r" (&(futex)), \
 161           "r" (LLL_LOCK_INITIALIZER_WAITERS), \
 162           "r" (LLL_LOCK_INITIALIZER) \
 163         : "r0", "r1", "r2", "t", "memory"); \
 164      __result; })
 165
 166 #define lll_lock(futex, private) \
 167   (void) ({ int __result, *__futex = &(futex); \
 168             __asm __volatile ("\
 169                 .align 2\n\
 170                 mova 1f,r0\n\
 171                 nop\n\
 172                 mov r15,r1\n\
 173                 mov #-8,r15\n\
 174              0: mov.l @%2,%0\n\
 175                 tst %0,%0\n\
 176                 bf 1f\n\
 177                 mov.l %1,@%2\n\
 178              1: mov r1,r15"\
 179                 : "=&r" (__result) : "r" (1), "r" (__futex) \
 180                 : "r0", "r1", "t", "memory"); \
 181             if (__result) \
 182               { \
 183                 if (__builtin_constant_p (private) \
 184                     && (private) == LLL_PRIVATE) \
 185                   __lll_lock_wait_private (__result, __futex); \
 186                 else \
 187                   __lll_lock_wait (__result, __futex, (private));       \
 188               } \
 189     })
 190
 191 #define lll_robust_lock(futex, id, private) \
 192   ({ int __result, *__futex = &(futex); \
 193      __asm __volatile ("\
 194         .align 2\n\
 195         mova 1f,r0\n\
 196         nop\n\
 197         mov r15,r1\n\
 198         mov #-8,r15\n\
 199       0: mov.l @%2,%0\n\
 200         tst %0,%0\n\
 201         bf 1f\n\
 202         mov.l %1,@%2\n\
 203       1: mov r1,r15"\
 204         : "=&r" (__result) : "r" (id), "r" (__futex) \
 205         : "r0", "r1", "t", "memory"); \
 206      if (__result) \
 207        __result = __lll_robust_lock_wait (__result, __futex, private); \
 208      __result; })
 209
 210 /* Special version of lll_mutex_lock which causes the unlock function to
 211    always wakeup waiters.  */
 212 #define lll_cond_lock(futex, private) \
 213   (void) ({ int __result, *__futex = &(futex); \
 214             __asm __volatile ("\
 215                 .align 2\n\
 216                 mova 1f,r0\n\
 217                 nop\n\
 218                 mov r15,r1\n\
 219                 mov #-8,r15\n\
 220              0: mov.l @%2,%0\n\
 221                 tst %0,%0\n\
 222                 bf 1f\n\
 223                 mov.l %1,@%2\n\
 224              1: mov r1,r15"\
 225                 : "=&r" (__result) : "r" (2), "r" (__futex) \
 226                 : "r0", "r1", "t", "memory"); \
 227             if (__result) \
 228               __lll_lock_wait (__result, __futex, private); })
 229
 230 #define lll_robust_cond_lock(futex, id, private) \
 231   ({ int __result, *__futex = &(futex); \
 232      __asm __volatile ("\
 233         .align 2\n\
 234         mova 1f,r0\n\
 235         nop\n\
 236         mov r15,r1\n\
 237         mov #-8,r15\n\
 238      0: mov.l @%2,%0\n\
 239         tst %0,%0\n\
 240         bf 1f\n\
 241         mov.l %1,@%2\n\
 242      1: mov r1,r15"\
 243         : "=&r" (__result) : "r" (id | FUTEX_WAITERS), "r" (__futex) \
 244         : "r0", "r1", "t", "memory"); \
 245       if (__result) \
 246         __result = __lll_robust_lock_wait (__result, __futex, private); \
 247       __result; })
 248
 249 #define lll_timedlock(futex, timeout, private) \
 250   ({ int __result, *__futex = &(futex); \
 251      __asm __volatile ("\
 252         .align 2\n\
 253         mova 1f,r0\n\
 254         nop\n\
 255         mov r15,r1\n\
 256         mov #-8,r15\n\
 257      0: mov.l @%2,%0\n\
 258         tst %0,%0\n\
 259         bf 1f\n\
 260         mov.l %1,@%2\n\
 261      1: mov r1,r15"\
 262         : "=&r" (__result) : "r" (1), "r" (__futex) \
 263         : "r0", "r1", "t", "memory"); \
 264     if (__result) \
 265       __result = __lll_timedlock_wait (__result, __futex, timeout, private); \
 266     __result; })
 267
 268 #define lll_robust_timedlock(futex, timeout, id, private) \
 269   ({ int __result, *__futex = &(futex); \
 270      __asm __volatile ("\
 271         .align 2\n\
 272         mova 1f,r0\n\
 273         nop\n\
 274         mov r15,r1\n\
 275         mov #-8,r15\n\
 276      0: mov.l @%2,%0\n\
 277         tst %0,%0\n\
 278         bf 1f\n\
 279         mov.l %1,@%2\n\
 280      1: mov r1,r15"\
 281         : "=&r" (__result) : "r" (id), "r" (__futex) \
 282         : "r0", "r1", "t", "memory"); \
 283     if (__result) \
 284       __result = __lll_robust_timedlock_wait (__result, __futex, \
 285                                               timeout, private); \
 286     __result; })
 287
 288 #define lll_unlock(futex, private) \
 289   (void) ({ int __result, *__futex = &(futex); \
 290             __asm __volatile ("\
 291                 .align 2\n\
 292                 mova 1f,r0\n\
 293                 mov r15,r1\n\
 294                 mov #-6,r15\n\
 295              0: mov.l @%1,%0\n\
 296                 add #-1,%0\n\
 297                 mov.l %0,@%1\n\
 298              1: mov r1,r15"\
 299                 : "=&r" (__result) : "r" (__futex) \
 300                 : "r0", "r1", "memory"); \
 301             if (__result) \
 302               { \
 303                 if (__builtin_constant_p (private) \
 304                     && (private) == LLL_PRIVATE) \
 305                   __lll_unlock_wake_private (__futex); \
 306                 else \
 307                   __lll_unlock_wake (__futex, (private)); \
 308               } \
 309     })
 310
 311 #define lll_robust_unlock(futex, private) \
 312   (void) ({ int __result, *__futex = &(futex); \
 313             __asm __volatile ("\
 314                 .align 2\n\
 315                 mova 1f,r0\n\
 316                 mov r15,r1\n\
 317                 mov #-6,r15\n\
 318              0: mov.l @%1,%0\n\
 319                 and %2,%0\n\
 320                 mov.l %0,@%1\n\
 321              1: mov r1,r15"\
 322                 : "=&r" (__result) : "r" (__futex), "r" (FUTEX_WAITERS) \
 323                 : "r0", "r1", "memory");        \
 324             if (__result) \
 325               __lll_unlock_wake (__futex, private); })
 326
 327 #define lll_robust_dead(futex, private)                \
 328   (void) ({ int __ignore, *__futex = &(futex); \
 329             __asm __volatile ("\
 330                 .align 2\n\
 331                 mova 1f,r0\n\
 332                 mov r15,r1\n\
 333                 mov #-6,r15\n\
 334              0: mov.l @%1,%0\n\
 335                 or %2,%0\n\
 336                 mov.l %0,@%1\n\
 337              1: mov r1,r15"\
 338                 : "=&r" (__ignore) : "r" (__futex), "r" (FUTEX_OWNER_DIED) \
 339                 : "r0", "r1", "memory");        \
 340             lll_futex_wake (__futex, 1, private); })
 341
 342 # ifdef NEED_SYSCALL_INST_PAD
 343 #  define SYSCALL_WITH_INST_PAD "\
 344         trapa #0x14; or r0,r0; or r0,r0; or r0,r0; or r0,r0; or r0,r0"
 345 # else
 346 #  define SYSCALL_WITH_INST_PAD "\
 347         trapa #0x14"
 348 # endif
 349
 350 #define lll_futex_wait(futex, val, private) \
 351   lll_futex_timed_wait (futex, val, NULL, private)
 352
 353
 354 #define lll_futex_timed_wait(futex, val, timeout, private) \
 355   ({                                                                          \
 356     int __status;                                                             \
 357     register unsigned long __r3 asm ("r3") = SYS_futex;                       \
 358     register unsigned long __r4 asm ("r4") = (unsigned long) (futex);         \
 359     register unsigned long __r5 asm ("r5")                                    \
 360       = __lll_private_flag (FUTEX_WAIT, private);                             \
 361     register unsigned long __r6 asm ("r6") = (unsigned long) (val);           \
 362     register unsigned long __r7 asm ("r7") = (timeout);                       \
 363     __asm __volatile (SYSCALL_WITH_INST_PAD                                   \
 364                       : "=z" (__status)                                       \
 365                       : "r" (__r3), "r" (__r4), "r" (__r5),                   \
 366                         "r" (__r6), "r" (__r7)                                \
 367                       : "memory", "t");                                       \
 368     __status;                                                                 \
 369   })
 370
 371
 372 #define lll_futex_wake(futex, nr, private) \
 373   do {                                                                        \
 374     int __ignore;                                                             \
 375     register unsigned long __r3 asm ("r3") = SYS_futex;                       \
 376     register unsigned long __r4 asm ("r4") = (unsigned long) (futex);         \
 377     register unsigned long __r5 asm ("r5")                                    \
 378       = __lll_private_flag (FUTEX_WAKE, private);                             \
 379     register unsigned long __r6 asm ("r6") = (unsigned long) (nr);            \
 380     register unsigned long __r7 asm ("r7") = 0;                               \
 381     __asm __volatile (SYSCALL_WITH_INST_PAD                                   \
 382                       : "=z" (__ignore)                                       \
 383                       : "r" (__r3), "r" (__r4), "r" (__r5),                   \
 384                         "r" (__r6), "r" (__r7)                                \
 385                       : "memory", "t");                                       \
 386   } while (0)
 387
 388
 389 #define lll_islocked(futex) \
 390   (futex != LLL_LOCK_INITIALIZER)
 391
 392 /* The kernel notifies a process with uses CLONE_CLEARTID via futex
 393    wakeup when the clone terminates.  The memory location contains the
 394    thread ID while the clone is running and is reset to zero
 395    afterwards.  */
 396
 397 #define lll_wait_tid(tid) \
 398   do {                                                                        \
 399     __typeof (tid) *__tid = &(tid);                                           \
 400     while (*__tid != 0)                                                       \
 401       lll_futex_wait (__tid, *__tid, LLL_SHARED);                             \
 402   } while (0)
 403
 404 extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime)
 405      attribute_hidden;
 406 #define lll_timedwait_tid(tid, abstime) \
 407   ({                                                                          \
 408     int __result = 0;                                                         \
 409     if (tid != 0)                                                             \
 410       {                                                                       \
 411         if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000)           \
 412           __result = EINVAL;                                                  \
 413         else                                                                  \
 414           __result = __lll_timedwait_tid (&tid, abstime);                     \
 415       }                                                                       \
 416     __result; })
 417
 418 #endif  /* !__ASSEMBLER__ */
 419
 420 #endif  /* lowlevellock.h */