diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S b/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S new file mode 100644 index 0000000000..738c067780 --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S @@ -0,0 +1,151 @@ +/* Copyright (C) 2002-2014 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, see + <http://www.gnu.org/licenses/>. */ + +#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 + pushl %ebx + cfi_adjust_cfa_offset(4) + pushl %edi + cfi_adjust_cfa_offset(4) + cfi_offset(%ebx, -8) + cfi_offset(%edi, -12) + + movl 12(%esp), %edi + + /* Get the lock. */ + movl $1, %edx + xorl %eax, %eax + LOCK +#if MUTEX == 0 + cmpxchgl %edx, (%edi) +#else + cmpxchgl %edx, MUTEX(%edi) +#endif + jnz 1f + +2: cmpl $0, WRITER(%edi) + jne 5f + subl $1, NR_READERS(%edi) + jnz 6f + +5: movl $0, WRITER(%edi) + + movl $1, %edx + leal WRITERS_WAKEUP(%edi), %ebx + cmpl $0, WRITERS_QUEUED(%edi) + jne 0f + + /* If also no readers waiting nothing to do. */ + cmpl $0, READERS_QUEUED(%edi) + je 6f + + movl $0x7fffffff, %edx + leal READERS_WAKEUP(%edi), %ebx + +0: addl $1, (%ebx) + LOCK +#if MUTEX == 0 + subl $1, (%edi) +#else + subl $1, MUTEX(%edi) +#endif + jne 7f + +8: +#ifdef __ASSUME_PRIVATE_FUTEX + movzbl PSHARED(%edi), %ecx + xorl $FUTEX_PRIVATE_FLAG|FUTEX_WAKE, %ecx +#else + movzbl PSHARED(%edi), %ecx + orl $FUTEX_WAKE, %ecx + xorl %gs:PRIVATE_FUTEX, %ecx +#endif + movl $SYS_futex, %eax + ENTER_KERNEL + + xorl %eax, %eax + popl %edi + cfi_adjust_cfa_offset(-4) + cfi_restore(%edi) + popl %ebx + cfi_adjust_cfa_offset(-4) + cfi_restore(%ebx) + ret + + cfi_adjust_cfa_offset(8) + cfi_offset(%ebx, -8) + cfi_offset(%edi, -12) + .align 16 +6: LOCK +#if MUTEX == 0 + subl $1, (%edi) +#else + subl $1, MUTEX(%edi) +#endif + jne 3f + +4: xorl %eax, %eax + popl %edi + popl %ebx + ret + +1: +#if MUTEX == 0 + movl %edi, %edx +#else + leal MUTEX(%edi), %edx +#endif + movzbl PSHARED(%edi), %ecx + call __lll_lock_wait + jmp 2b + +3: +#if MUTEX == 0 + movl %edi, %eax +#else + leal MUTEX(%edi), %eax +#endif + movzbl PSHARED(%edi), %ecx + call __lll_unlock_wake + jmp 4b + +7: +#if MUTEX == 0 + movl %edi, %eax +#else + leal MUTEX(%edi), %eax +#endif + movzbl PSHARED(%edi), %ecx + call __lll_unlock_wake + jmp 8b + cfi_endproc + .size __pthread_rwlock_unlock,.-__pthread_rwlock_unlock + +strong_alias (__pthread_rwlock_unlock, pthread_rwlock_unlock) +hidden_def (__pthread_rwlock_unlock) |