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authorUlrich Drepper <drepper@redhat.com>2009-01-03 23:17:21 +0000
committerUlrich Drepper <drepper@redhat.com>2009-01-03 23:17:21 +0000
commit45f7760695429b98d2edb9f895f035c35a2fbcd7 (patch)
tree4b6e41f700b040bf95df7c2a9e402de8a3d556c5 /nptl
parent5aff6fdfb7434da804e08f8cdf7ca83263719245 (diff)
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(__lll_timedlock_wait): Use FUTEX_WAIT_BITSET|FUTEX_CLOCK_READTIME instead of computing relative timeout.
Diffstat (limited to 'nptl')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S98
1 files changed, 79 insertions, 19 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S
index 9c8a68f5b2..056b72900a 100644
--- a/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S
+++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003, 2004, 2006, 2007 Free Software Foundation, Inc.
+/* Copyright (C) 2002-2004, 2006, 2007, 2009 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
@@ -31,6 +31,8 @@
movl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg
# define LOAD_FUTEX_WAIT(reg) \
xorl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
+# define LOAD_FUTEX_WAIT_ABS(reg) \
+ xorl $(FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME), reg
# define LOAD_FUTEX_WAKE(reg) \
xorl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg
#else
@@ -55,6 +57,10 @@
andl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT, reg
# endif
+# define LOAD_FUTEX_WAIT_ABS(reg) \
+ xorl $FUTEX_PRIVATE_FLAG, reg ; \
+ andl %gs:PRIVATE_FUTEX, reg ; \
+ orl $FUTEX_WAIT | FUTEX_CLOCK_REALTIME, reg
# define LOAD_FUTEX_WAKE(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg ; \
@@ -154,28 +160,81 @@ __lll_lock_wait:
cfi_endproc
.size __lll_lock_wait,.-__lll_lock_wait
+ /* %ecx: futex
+ %esi: flags
+ %edx: timeout
+ %eax: futex value
+ */
.globl __lll_timedlock_wait
.type __lll_timedlock_wait,@function
.hidden __lll_timedlock_wait
.align 16
__lll_timedlock_wait:
cfi_startproc
+ pushl %ebp
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%ebp, 0)
+ pushl %ebx
+ cfi_adjust_cfa_offset(4)
+ cfi_rel_offset(%ebx, 0)
+
+# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
+# ifdef PIC
+ LOAD_PIC_REG (bx)
+ cmpl $0, __have_futex_clock_realtime@GOTOFF(%ebx)
+# else
+ cmpl $0, __have_futex_clock_realtime
+# endif
+ je .Lreltmo
+# endif
+
+ movl %ecx, %ebx
+ movl %esi, %ecx
+ movl %edx, %esi
+ movl $0xffffffff, %ebp
+ LOAD_FUTEX_WAIT_ABS (%ecx)
+
+ movl $2, %edx
+ cmpl %edx, %eax
+ jne 2f
+
+1: movl $SYS_futex, %eax
+ movl $2, %edx
+ ENTER_KERNEL
+
+2: xchgl %edx, (%ebx) /* NB: lock is implied */
+
+ testl %edx, %edx
+ jz 3f
+
+ cmpl $-ETIMEDOUT, %eax
+ je 4f
+ cmpl $-EINVAL, %eax
+ jne 1b
+4: movl %eax, %edx
+ negl %edx
+
+3: movl %edx, %eax
+7: popl %ebx
+ cfi_adjust_cfa_offset(-4)
+ cfi_restore(%ebx)
+ popl %ebp
+ cfi_adjust_cfa_offset(-4)
+ cfi_restore(%ebp)
+ ret
+
+# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
+.Lreltmo:
/* Check for a valid timeout value. */
cmpl $1000000000, 4(%edx)
jae 3f
- pushl %edi
- cfi_adjust_cfa_offset(4)
pushl %esi
cfi_adjust_cfa_offset(4)
- pushl %ebx
- cfi_adjust_cfa_offset(4)
- pushl %ebp
+ cfi_rel_offset(%esi, 0)
+ pushl %edi
cfi_adjust_cfa_offset(4)
- cfi_offset(%edi, -8)
- cfi_offset(%esi, -12)
- cfi_offset(%ebx, -16)
- cfi_offset(%ebp, -20)
+ cfi_rel_offset(%edi, 0)
/* Stack frame for the timespec and timeval structs. */
subl $8, %esp
@@ -236,23 +295,24 @@ __lll_timedlock_wait:
6: addl $8, %esp
cfi_adjust_cfa_offset(-8)
- popl %ebp
- cfi_adjust_cfa_offset(-4)
- cfi_restore(%ebp)
- popl %ebx
+ popl %edi
cfi_adjust_cfa_offset(-4)
- cfi_restore(%ebx)
+ cfi_restore(%edi)
popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
- popl %edi
+7: popl %ebx
cfi_adjust_cfa_offset(-4)
- cfi_restore(%edi)
+ cfi_restore(%ebx)
+ popl %ebp
+ cfi_adjust_cfa_offset(-4)
+ cfi_restore(%ebp)
movl %edx, %eax
ret
-3: movl $EINVAL, %eax
- ret
+3: movl $EINVAL, %edx
+ jmp 7b
+# endif
cfi_endproc
.size __lll_timedlock_wait,.-__lll_timedlock_wait
#endif