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-rw-r--r--nptl/sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S192
1 files changed, 192 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S
new file mode 100644
index 0000000000..7bb9191691
--- /dev/null
+++ b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevelrobustlock.S
@@ -0,0 +1,192 @@
+/* Copyright (C) 2002, 2003, 2004, 2005, 2006 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 <pthread-errnos.h>
+#include <lowlevelrobustlock.h>
+
+ .text
+
+#ifndef LOCK
+# ifdef UP
+# define LOCK
+# else
+# define LOCK lock
+# endif
+#endif
+
+#define SYS_futex 202
+#define FUTEX_WAIT 0
+#define FUTEX_WAKE 1
+#define FUTEX_WAITERS 0x80000000
+#define FUTEX_OWNER_DIED 0x40000000
+
+/* For the calculation see asm/vsyscall.h. */
+#define VSYSCALL_ADDR_vgettimeofday 0xffffffffff600000
+
+
+ .globl __lll_robust_mutex_lock_wait
+ .type __lll_robust_mutex_lock_wait,@function
+ .hidden __lll_robust_mutex_lock_wait
+ .align 16
+__lll_robust_mutex_lock_wait:
+ pushq %r10
+ pushq %rdx
+
+ xorq %r10, %r10 /* No timeout. */
+#if FUTEX_WAIT == 0
+ xorl %esi, %esi
+#else
+ movl $FUTEX_WAIT, %esi
+#endif
+
+4: movl %eax, %edx
+ orl $FUTEX_WAITERS, %edx
+
+ testl $FUTEX_OWNER_DIED, %eax
+ jnz 3f
+
+ cmpl %edx, %eax
+ je 1f
+
+ LOCK
+ cmpxchgl %edx, (%rdi)
+ jnz 2f
+
+1: movl $SYS_futex, %eax
+ syscall
+
+ movl (%rdi), %eax
+
+2: testl %eax, %eax
+ jne 4b
+
+ movl %fs:TID, %edx
+ LOCK
+ cmpxchgl %edx, (%rdi)
+ jnz 4b
+ /* NB: %rax == 0 */
+
+3: popq %rdx
+ popq %r10
+ retq
+ .size __lll_robust_mutex_lock_wait,.-__lll_robust_mutex_lock_wait
+
+
+ .globl __lll_robust_mutex_timedlock_wait
+ .type __lll_robust_mutex_timedlock_wait,@function
+ .hidden __lll_robust_mutex_timedlock_wait
+ .align 16
+__lll_robust_mutex_timedlock_wait:
+ /* Check for a valid timeout value. */
+ cmpq $1000000000, 8(%rdx)
+ jae 3f
+
+ pushq %r8
+ pushq %r9
+ pushq %r12
+ pushq %r13
+
+ /* Stack frame for the timespec and timeval structs. */
+ subq $24, %rsp
+
+ movq %rdi, %r12
+ movq %rdx, %r13
+
+1: movq %rax, 16(%rsp)
+
+ /* Get current time. */
+ movq %rsp, %rdi
+ xorl %esi, %esi
+ movq $VSYSCALL_ADDR_vgettimeofday, %rax
+ /* This is a regular function call, all caller-save registers
+ might be clobbered. */
+ callq *%rax
+
+ /* Compute relative timeout. */
+ movq 8(%rsp), %rax
+ movl $1000, %edi
+ mul %rdi /* Milli seconds to nano seconds. */
+ movq (%r13), %rdi
+ movq 8(%r13), %rsi
+ subq (%rsp), %rdi
+ subq %rax, %rsi
+ jns 4f
+ addq $1000000000, %rsi
+ decq %rdi
+4: testq %rdi, %rdi
+ js 8f /* Time is already up. */
+
+ /* Futex call. */
+ movq %rdi, (%rsp) /* Store relative timeout. */
+ movq %rsi, 8(%rsp)
+
+ movq 16(%rsp), %rdx
+ movl %edx, %eax
+ orl $FUTEX_WAITERS, %edx
+
+ testl $FUTEX_OWNER_DIED, %eax
+ jnz 6f
+
+ cmpl %eax, %edx
+ je 2f
+
+ LOCK
+ cmpxchgl %edx, (%r12)
+ movq $0, %rcx /* Must use mov to avoid changing cc. */
+ jnz 5f
+
+2: movq %rsp, %r10
+#if FUTEX_WAIT == 0
+ xorl %esi, %esi
+#else
+ movl $FUTEX_WAIT, %esi
+#endif
+ movq %r12, %rdi
+ movl $SYS_futex, %eax
+ syscall
+ movq %rax, %rcx
+
+ movl (%r12), %eax
+
+5: testl %eax, %eax
+ jne 7f
+
+ movl %fs:TID, %edx
+ LOCK
+ cmpxchgl %edx, (%r12)
+ jnz 7f
+
+6: addq $24, %rsp
+ popq %r13
+ popq %r12
+ popq %r9
+ popq %r8
+ retq
+
+ /* Check whether the time expired. */
+7: cmpq $-ETIMEDOUT, %rcx
+ jne 1b
+
+8: movl $ETIMEDOUT, %eax
+ jmp 6b
+
+3: movl $EINVAL, %eax
+ retq
+ .size __lll_robust_mutex_timedlock_wait,.-__lll_robust_mutex_timedlock_wait