diff options
Diffstat (limited to 'libpthread/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S')
| -rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S b/libpthread/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S new file mode 100644 index 000000000..597c82fa8 --- /dev/null +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_unlock.S @@ -0,0 +1,140 @@ +/* Copyright (C) 2002, 2003 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 <lowlevelrwlock.h> + + +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + +#ifndef UP +# define LOCK lock +#else +# define LOCK +#endif + + + .text + + .globl __pthread_rwlock_unlock + .type __pthread_rwlock_unlock,@function + .align 16 +__pthread_rwlock_unlock: + pushl %ebx + pushl %edi + + 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, %ecx + leal WRITERS_WAKEUP(%edi), %ebx + movl %ecx, %edx + 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: movl $SYS_futex, %eax + ENTER_KERNEL + + xorl %eax, %eax + popl %edi + popl %ebx + ret + + .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, %ecx +#else + leal MUTEX(%edx), %ecx +#endif + call __lll_mutex_lock_wait + jmp 2b + +3: +#if MUTEX == 0 + movl %edi, %eax +#else + leal MUTEX(%edx), %eax +#endif + call __lll_mutex_unlock_wake + jmp 4b + +7: +#if MUTEX == 0 + movl %edi, %eax +#else + leal MUTEX(%edx), %eax +#endif + call __lll_mutex_unlock_wake + jmp 8b + + .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 |