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-rw-r--r--sysdeps/unix/sysv/linux/i386/pthread_cond_signal.S216
1 files changed, 216 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/pthread_cond_signal.S b/sysdeps/unix/sysv/linux/i386/pthread_cond_signal.S
new file mode 100644
index 0000000000..0038775d3f
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/i386/pthread_cond_signal.S
@@ -0,0 +1,216 @@
+/* Copyright (C) 2002-2016 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 <shlib-compat.h>
+#include <lowlevellock.h>
+#include <lowlevelcond.h>
+#include <kernel-features.h>
+#include <pthread-pi-defines.h>
+#include <pthread-errnos.h>
+#include <stap-probe.h>
+
+ .text
+
+ /* int pthread_cond_signal (pthread_cond_t *cond) */
+ .globl __pthread_cond_signal
+ .type __pthread_cond_signal, @function
+ .align 16
+__pthread_cond_signal:
+
+ cfi_startproc
+ pushl %ebx
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%ebx, 0)
+ pushl %edi
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%edi, 0)
+ cfi_remember_state
+
+ movl 12(%esp), %edi
+
+ LIBC_PROBE (cond_signal, 1, %edi)
+
+ /* Get internal lock. */
+ movl $1, %edx
+ xorl %eax, %eax
+ LOCK
+#if cond_lock == 0
+ cmpxchgl %edx, (%edi)
+#else
+ cmpxchgl %edx, cond_lock(%edi)
+#endif
+ jnz 1f
+
+2: leal cond_futex(%edi), %ebx
+ movl total_seq+4(%edi), %eax
+ movl total_seq(%edi), %ecx
+ cmpl wakeup_seq+4(%edi), %eax
+#if cond_lock != 0
+ /* Must use leal to preserve the flags. */
+ leal cond_lock(%edi), %edi
+#endif
+ ja 3f
+ jb 4f
+ cmpl wakeup_seq-cond_futex(%ebx), %ecx
+ jbe 4f
+
+ /* Bump the wakeup number. */
+3: addl $1, wakeup_seq-cond_futex(%ebx)
+ adcl $0, wakeup_seq-cond_futex+4(%ebx)
+ addl $1, (%ebx)
+
+ /* Wake up one thread. */
+ pushl %esi
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%esi, 0)
+ pushl %ebp
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%ebp, 0)
+
+#if FUTEX_PRIVATE_FLAG > 255
+ xorl %ecx, %ecx
+#endif
+ cmpl $-1, dep_mutex-cond_futex(%ebx)
+ sete %cl
+ je 8f
+
+ movl dep_mutex-cond_futex(%ebx), %edx
+ /* Requeue to a non-robust PI mutex if the PI bit is set and
+ the robust bit is not set. */
+ movl MUTEX_KIND(%edx), %eax
+ andl $(ROBUST_BIT|PI_BIT), %eax
+ cmpl $PI_BIT, %eax
+ je 9f
+
+8: subl $1, %ecx
+#ifdef __ASSUME_PRIVATE_FUTEX
+ andl $FUTEX_PRIVATE_FLAG, %ecx
+#else
+ andl %gs:PRIVATE_FUTEX, %ecx
+#endif
+ addl $FUTEX_WAKE_OP, %ecx
+ movl $SYS_futex, %eax
+ movl $1, %edx
+ movl $1, %esi
+ movl $FUTEX_OP_CLEAR_WAKE_IF_GT_ONE, %ebp
+ /* FIXME: Until Ingo fixes 4G/4G vDSO, 6 arg syscalls are broken for
+ sysenter.
+ ENTER_KERNEL */
+ int $0x80
+ popl %ebp
+ cfi_adjust_cfa_offset(-4)
+ cfi_restore(%ebp)
+ popl %esi
+ cfi_adjust_cfa_offset(-4)
+ cfi_restore(%esi)
+
+ /* For any kind of error, we try again with WAKE.
+ The general test also covers running on old kernels. */
+ cmpl $-4095, %eax
+ jae 7f
+
+6: 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_restore_state
+
+9: movl $(FUTEX_CMP_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %ecx
+ movl $SYS_futex, %eax
+ movl $1, %edx
+ xorl %esi, %esi
+ movl dep_mutex-cond_futex(%ebx), %edi
+ movl (%ebx), %ebp
+ /* FIXME: Until Ingo fixes 4G/4G vDSO, 6 arg syscalls are broken for
+ sysenter.
+ ENTER_KERNEL */
+ int $0x80
+ popl %ebp
+ popl %esi
+
+ leal -cond_futex(%ebx), %edi
+
+ /* For any kind of error, we try again with WAKE.
+ The general test also covers running on old kernels. */
+ cmpl $-4095, %eax
+ jb 4f
+
+7:
+#ifdef __ASSUME_PRIVATE_FUTEX
+ andl $FUTEX_PRIVATE_FLAG, %ecx
+#else
+ andl %gs:PRIVATE_FUTEX, %ecx
+#endif
+ orl $FUTEX_WAKE, %ecx
+
+ movl $SYS_futex, %eax
+ /* %edx should be 1 already from $FUTEX_WAKE_OP syscall.
+ movl $1, %edx */
+ ENTER_KERNEL
+
+ /* Unlock. Note that at this point %edi always points to
+ cond_lock. */
+4: LOCK
+ subl $1, (%edi)
+ je 6b
+
+ /* Unlock in loop requires wakeup. */
+5: movl %edi, %eax
+#if (LLL_SHARED-LLL_PRIVATE) > 255
+ xorl %ecx, %ecx
+#endif
+ cmpl $-1, dep_mutex-cond_futex(%ebx)
+ setne %cl
+ subl $1, %ecx
+ andl $(LLL_SHARED-LLL_PRIVATE), %ecx
+#if LLL_PRIVATE != 0
+ addl $LLL_PRIVATE, %ecx
+#endif
+ call __lll_unlock_wake
+ jmp 6b
+
+ /* Initial locking failed. */
+1:
+#if cond_lock == 0
+ movl %edi, %edx
+#else
+ leal cond_lock(%edi), %edx
+#endif
+#if (LLL_SHARED-LLL_PRIVATE) > 255
+ xorl %ecx, %ecx
+#endif
+ cmpl $-1, dep_mutex(%edi)
+ setne %cl
+ subl $1, %ecx
+ andl $(LLL_SHARED-LLL_PRIVATE), %ecx
+#if LLL_PRIVATE != 0
+ addl $LLL_PRIVATE, %ecx
+#endif
+ call __lll_lock_wait
+ jmp 2b
+
+ cfi_endproc
+ .size __pthread_cond_signal, .-__pthread_cond_signal
+versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,
+ GLIBC_2_3_2)