| /* Copyright (C) 2002, 2003, 2005, 2007, 2009 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@redhat.com>, 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 <sysdep.h> |
| #include <lowlevellock.h> |
| #include <lowlevelrwlock.h> |
| #include <kernel-features.h> |
| |
| |
| .text |
| |
| .globl __pthread_rwlock_unlock |
| .type __pthread_rwlock_unlock,@function |
| .align 16 |
| __pthread_rwlock_unlock: |
| cfi_startproc |
| /* Get the lock. */ |
| movl $1, %esi |
| xorl %eax, %eax |
| LOCK |
| #if MUTEX == 0 |
| cmpxchgl %esi, (%rdi) |
| #else |
| cmpxchgl %esi, MUTEX(%rdi) |
| #endif |
| jnz 1f |
| |
| 2: cmpl $0, WRITER(%rdi) |
| jne 5f |
| decl NR_READERS(%rdi) |
| jnz 6f |
| |
| 5: movl $0, WRITER(%rdi) |
| |
| movl $1, %edx |
| leaq WRITERS_WAKEUP(%rdi), %r10 |
| cmpl $0, WRITERS_QUEUED(%rdi) |
| jne 0f |
| |
| /* If also no readers waiting nothing to do. */ |
| cmpl $0, READERS_QUEUED(%rdi) |
| je 6f |
| |
| movl $0x7fffffff, %edx |
| leaq READERS_WAKEUP(%rdi), %r10 |
| |
| 0: incl (%r10) |
| LOCK |
| #if MUTEX == 0 |
| decl (%rdi) |
| #else |
| decl MUTEX(%rdi) |
| #endif |
| jne 7f |
| |
| 8: |
| #ifdef __ASSUME_PRIVATE_FUTEX |
| movl $FUTEX_PRIVATE_FLAG|FUTEX_WAKE, %esi |
| xorl PSHARED(%rdi), %esi |
| #else |
| movl $FUTEX_WAKE, %esi |
| orl PSHARED(%rdi), %esi |
| xorl %fs:PRIVATE_FUTEX, %esi |
| #endif |
| movl $SYS_futex, %eax |
| movq %r10, %rdi |
| syscall |
| |
| xorl %eax, %eax |
| retq |
| |
| .align 16 |
| 6: LOCK |
| #if MUTEX == 0 |
| decl (%rdi) |
| #else |
| decl MUTEX(%rdi) |
| #endif |
| jne 3f |
| |
| 4: xorl %eax, %eax |
| retq |
| |
| 1: movl PSHARED(%rdi), %esi |
| #if MUTEX != 0 |
| addq $MUTEX, %rdi |
| #endif |
| callq __lll_lock_wait |
| #if MUTEX != 0 |
| subq $MUTEX, %rdi |
| #endif |
| jmp 2b |
| |
| 3: movl PSHARED(%rdi), %esi |
| #if MUTEX != 0 |
| addq $MUTEX, %rdi |
| #endif |
| callq __lll_unlock_wake |
| jmp 4b |
| |
| 7: movl PSHARED(%rdi), %esi |
| #if MUTEX != 0 |
| addq $MUTEX, %rdi |
| #endif |
| callq __lll_unlock_wake |
| jmp 8b |
| cfi_endproc |
| .size __pthread_rwlock_unlock,.-__pthread_rwlock_unlock |
| |
| .globl pthread_rwlock_unlock |
| pthread_rwlock_unlock = __pthread_rwlock_unlock |
| |
| .globl __pthread_rwlock_unlock_internal |
| __pthread_rwlock_unlock_internal = __pthread_rwlock_unlock |
