Handle EAGAIN from FUTEX_WAIT_REQUEUE_PI

This commit is contained in:
Andreas Schwab 2011-11-28 13:38:19 +01:00
parent 9d65ea3a9b
commit c5a0802a68
3 changed files with 160 additions and 2 deletions

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@ -1,3 +1,9 @@
2011-11-28 Andreas Schwab <schwab@redhat.com>
* sysdeps/unix/sysv/linux/i386/i486/pthread_cond_wait.S: Handle
EAGAIN from FUTEX_WAIT_REQUEUE_PI.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S: Likewise.
2011-11-17 Ulrich Drepper <drepper@gmail.com>
* Makefile.in: Remove CVSOPT handling.

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@ -134,6 +134,7 @@ __pthread_cond_wait:
cmpl $PI_BIT, %eax
jne 18f
90:
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %ecx
movl %ebp, %edx
xorl %esi, %esi
@ -147,6 +148,9 @@ __pthread_cond_wait:
sete 16(%esp)
je 19f
cmpl $-EAGAIN, %eax
je 91f
/* Normal and PI futexes dont mix. Use normal futex functions only
if the kernel does not support the PI futex functions. */
cmpl $-ENOSYS, %eax
@ -391,6 +395,78 @@ __pthread_cond_wait:
#endif
call __lll_unlock_wake
jmp 11b
91:
.LcleanupSTART2:
/* FUTEX_WAIT_REQUEUE_PI returned EAGAIN. We need to
call it again. */
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jz 92f
#if cond_lock == 0
movl %ebx, %edx
#else
leal cond_lock(%ebx), %edx
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_lock_wait
92:
/* Increment the cond_futex value again, so it can be used as a new
expected value. */
addl $1, cond_futex(%ebx)
movl cond_futex(%ebx), %ebp
/* Unlock. */
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
je 93f
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%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
93:
/* Set the rest of SYS_futex args for FUTEX_WAIT_REQUEUE_PI. */
xorl %ecx, %ecx
movl dep_mutex(%ebx), %edi
jmp 90b
.LcleanupEND2:
.size __pthread_cond_wait, .-__pthread_cond_wait
versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
GLIBC_2_3_2)
@ -563,6 +639,10 @@ __condvar_w_cleanup:
.long .LcleanupEND-.Lsub_cond_futex
.long __condvar_w_cleanup-.LSTARTCODE
.uleb128 0
.long .LcleanupSTART2-.LSTARTCODE
.long .LcleanupEND2-.LcleanupSTART2
.long __condvar_w_cleanup-.LSTARTCODE
.uleb128 0
.long .LcallUR-.LSTARTCODE
.long .LENDCODE-.LcallUR
.long 0

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@ -23,6 +23,7 @@
#include <lowlevelcond.h>
#include <tcb-offsets.h>
#include <pthread-pi-defines.h>
#include <pthread-errnos.h>
#include <kernel-features.h>
@ -133,11 +134,14 @@ __pthread_cond_wait:
cmpl $PI_BIT, %eax
jne 61f
90:
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %esi
movl $SYS_futex, %eax
syscall
movl $1, %r8d
cmpq $-EAGAIN, %rax
je 91f
#ifdef __ASSUME_REQUEUE_PI
jmp 62f
#else
@ -324,6 +328,70 @@ __pthread_cond_wait:
13: movq %r10, %rax
jmp 14b
91:
.LcleanupSTART2:
/* FUTEX_WAIT_REQUEUE_PI returned EAGAIN. We need to
call it again. */
movq 8(%rsp), %rdi
/* Get internal lock. */
movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jz 92f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
cmpq $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_lock_wait
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
92:
/* Increment the cond_futex value again, so it can be used as a new
expected value. */
incl cond_futex(%rdi)
movl cond_futex(%rdi), %edx
/* Release internal lock. */
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jz 93f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
cmpq $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
/* The call preserves %rdx. */
callq __lll_unlock_wake
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
93:
/* Set the rest of SYS_futex args for FUTEX_WAIT_REQUEUE_PI. */
xorq %r10, %r10
movq dep_mutex(%rdi), %r8
leaq cond_futex(%rdi), %rdi
jmp 90b
.LcleanupEND2:
.size __pthread_cond_wait, .-__pthread_cond_wait
versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
GLIBC_2_3_2)
@ -476,11 +544,15 @@ __condvar_cleanup1:
.uleb128 .LcleanupSTART-.LSTARTCODE
.uleb128 .LcleanupEND-.LcleanupSTART
.uleb128 __condvar_cleanup1-.LSTARTCODE
.uleb128 0
.uleb128 0
.uleb128 .LcleanupSTART2-.LSTARTCODE
.uleb128 .LcleanupEND2-.LcleanupSTART2
.uleb128 __condvar_cleanup1-.LSTARTCODE
.uleb128 0
.uleb128 .LcallUR-.LSTARTCODE
.uleb128 .LENDCODE-.LcallUR
.uleb128 0
.uleb128 0
.uleb128 0
.Lcstend: