/* Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 2002. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include #include #include "pthreadP.h" #include int internal_function attribute_hidden __pthread_mutex_unlock_usercnt (mutex, decr) pthread_mutex_t *mutex; int decr; { int newowner = 0; switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP)) { case PTHREAD_MUTEX_RECURSIVE_NP: /* Recursive mutex. */ if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)) return EPERM; if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return 0; goto normal; case PTHREAD_MUTEX_ERRORCHECK_NP: /* Error checking mutex. */ if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid) || ! lll_mutex_islocked (mutex->__data.__lock)) return EPERM; /* FALLTHROUGH */ case PTHREAD_MUTEX_TIMED_NP: case PTHREAD_MUTEX_ADAPTIVE_NP: /* Always reset the owner field. */ normal: mutex->__data.__owner = 0; if (decr) /* One less user. */ --mutex->__data.__nusers; /* Unlock. */ lll_mutex_unlock (mutex->__data.__lock); break; case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP: /* Recursive mutex. */ if ((mutex->__data.__lock & FUTEX_TID_MASK) == THREAD_GETMEM (THREAD_SELF, tid) && __builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_INCONSISTENT, 0)) { if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return ENOTRECOVERABLE; goto notrecoverable; } if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)) return EPERM; if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return 0; goto robust; case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP: if ((mutex->__data.__lock & FUTEX_TID_MASK) != THREAD_GETMEM (THREAD_SELF, tid) || ! lll_mutex_islocked (mutex->__data.__lock)) return EPERM; /* If the previous owner died and the caller did not succeed in making the state consistent, mark the mutex as unrecoverable and make all waiters. */ if (__builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_INCONSISTENT, 0)) notrecoverable: newowner = PTHREAD_MUTEX_NOTRECOVERABLE; robust: /* Remove mutex from the list. */ THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, &mutex->__data.__list.__next); DEQUEUE_MUTEX (mutex); mutex->__data.__owner = newowner; if (decr) /* One less user. */ --mutex->__data.__nusers; /* Unlock. */ lll_robust_mutex_unlock (mutex->__data.__lock); THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; case PTHREAD_MUTEX_PI_RECURSIVE_NP: /* Recursive mutex. */ if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)) return EPERM; if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return 0; goto continue_pi; case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP: /* Recursive mutex. */ if ((mutex->__data.__lock & FUTEX_TID_MASK) == THREAD_GETMEM (THREAD_SELF, tid) && __builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_INCONSISTENT, 0)) { if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return ENOTRECOVERABLE; goto pi_notrecoverable; } if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)) return EPERM; if (--mutex->__data.__count != 0) /* We still hold the mutex. */ return 0; goto continue_pi; case PTHREAD_MUTEX_PI_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_NORMAL_NP: case PTHREAD_MUTEX_PI_ADAPTIVE_NP: case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP: case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP: case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP: if ((mutex->__data.__lock & FUTEX_TID_MASK) != THREAD_GETMEM (THREAD_SELF, tid) || ! lll_mutex_islocked (mutex->__data.__lock)) return EPERM; /* If the previous owner died and the caller did not succeed in making the state consistent, mark the mutex as unrecoverable and make all waiters. */ if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0 && __builtin_expect (mutex->__data.__owner == PTHREAD_MUTEX_INCONSISTENT, 0)) pi_notrecoverable: newowner = PTHREAD_MUTEX_NOTRECOVERABLE; continue_pi: if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0) { /* Remove mutex from the list. Note: robust PI futexes are signaled by setting bit 0. */ THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, (void *) (((uintptr_t) &mutex->__data.__list.__next) | 1)); DEQUEUE_MUTEX (mutex); } mutex->__data.__owner = newowner; if (decr) /* One less user. */ --mutex->__data.__nusers; /* Unlock. */ if ((mutex->__data.__lock & FUTEX_WAITERS) != 0 || atomic_compare_and_exchange_bool_acq (&mutex->__data.__lock, 0, THREAD_GETMEM (THREAD_SELF, tid))) { INTERNAL_SYSCALL_DECL (__err); INTERNAL_SYSCALL (futex, __err, 2, &mutex->__data.__lock, FUTEX_UNLOCK_PI); } THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL); break; default: /* Correct code cannot set any other type. */ return EINVAL; } return 0; } int __pthread_mutex_unlock (mutex) pthread_mutex_t *mutex; { return __pthread_mutex_unlock_usercnt (mutex, 1); } strong_alias (__pthread_mutex_unlock, pthread_mutex_unlock) strong_alias (__pthread_mutex_unlock, __pthread_mutex_unlock_internal)