diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_wrlock.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_wrlock.S | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_wrlock.S b/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_wrlock.S new file mode 100644 index 0000000000..8345cae1ea --- /dev/null +++ b/sysdeps/unix/sysv/linux/i386/i486/pthread_rwlock_wrlock.S @@ -0,0 +1,183 @@ +/* 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 <pthread-errnos.h> +#include <kernel-features.h> + +#include <stap-probe.h> + + .text + + .globl __pthread_rwlock_wrlock + .type __pthread_rwlock_wrlock,@function + .align 16 +__pthread_rwlock_wrlock: + cfi_startproc + pushl %esi + cfi_adjust_cfa_offset(4) + pushl %ebx + cfi_adjust_cfa_offset(4) + cfi_offset(%esi, -8) + cfi_offset(%ebx, -12) + + xorl %esi, %esi + movl 12(%esp), %ebx + + LIBC_PROBE (wrlock_entry, 1, %ebx) + + /* Get the lock. */ + movl $1, %edx + xorl %eax, %eax + LOCK +#if MUTEX == 0 + cmpxchgl %edx, (%ebx) +#else + cmpxchgl %edx, MUTEX(%ebx) +#endif + jnz 1f + +2: movl WRITER(%ebx), %eax + testl %eax, %eax + jne 14f + cmpl $0, NR_READERS(%ebx) + je 5f + +3: addl $1, WRITERS_QUEUED(%ebx) + je 4f + + movl WRITERS_WAKEUP(%ebx), %edx + + LOCK +#if MUTEX == 0 + subl $1, (%ebx) +#else + subl $1, MUTEX(%ebx) +#endif + jne 10f + +11: +#ifdef __ASSUME_PRIVATE_FUTEX + movzbl PSHARED(%ebx), %ecx + xorl $FUTEX_PRIVATE_FLAG|FUTEX_WAIT, %ecx +#else + movzbl PSHARED(%ebx), %ecx +# if FUTEX_WAIT != 0 + orl $FUTEX_WAIT, %ecx +# endif + xorl %gs:PRIVATE_FUTEX, %ecx +#endif + addl $WRITERS_WAKEUP, %ebx + movl $SYS_futex, %eax + ENTER_KERNEL + + subl $WRITERS_WAKEUP, %ebx + + /* Reget the lock. */ + movl $1, %edx + xorl %eax, %eax + LOCK +#if MUTEX == 0 + cmpxchgl %edx, (%ebx) +#else + cmpxchgl %edx, MUTEX(%ebx) +#endif + jnz 12f + +13: subl $1, WRITERS_QUEUED(%ebx) + jmp 2b + +5: xorl %edx, %edx + movl %gs:TID, %eax + movl %eax, WRITER(%ebx) +9: LOCK +#if MUTEX == 0 + subl $1, (%ebx) +#else + subl $1, MUTEX(%ebx) +#endif + jne 6f +7: + + movl %edx, %eax + popl %ebx + cfi_adjust_cfa_offset(-4) + cfi_restore(%ebx) + popl %esi + cfi_adjust_cfa_offset(-4) + cfi_restore(%esi) + ret + + cfi_adjust_cfa_offset(8) + cfi_offset(%esi, -8) + cfi_offset(%ebx, -12) +1: +#if MUTEX == 0 + movl %ebx, %edx +#else + leal MUTEX(%ebx), %edx +#endif + movzbl PSHARED(%ebx), %ecx + call __lll_lock_wait + jmp 2b + +14: cmpl %gs:TID , %eax + jne 3b + movl $EDEADLK, %edx + jmp 9b + +6: +#if MUTEX == 0 + movl %ebx, %eax +#else + leal MUTEX(%ebx), %eax +#endif + movzbl PSHARED(%ebx), %ecx + call __lll_unlock_wake + jmp 7b + +4: subl $1, WRITERS_QUEUED(%ebx) + movl $EAGAIN, %edx + jmp 9b + +10: +#if MUTEX == 0 + movl %ebx, %eax +#else + leal MUTEX(%ebx), %eax +#endif + movzbl PSHARED(%ebx), %ecx + call __lll_unlock_wake + jmp 11b + +12: +#if MUTEX == 0 + movl %ebx, %edx +#else + leal MUTEX(%ebx), %edx +#endif + movzbl PSHARED(%ebx), %ecx + call __lll_lock_wait + jmp 13b + cfi_endproc + .size __pthread_rwlock_wrlock,.-__pthread_rwlock_wrlock + +strong_alias (__pthread_rwlock_wrlock, pthread_rwlock_wrlock) +hidden_def (__pthread_rwlock_wrlock) |