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| author | Ulrich Drepper <drepper@redhat.com> | 2007-11-09 09:09:07 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2007-11-09 09:09:07 +0000 |
| commit | cbed6a607d6b42b0cb264d2bee1bd784c8504d60 (patch) | |
| tree | ddbae943982b9b03fc676bf98ce597273de2c268 | |
| parent | 0f7e0ee507c4bfba62c9059451197e9a25a0598e (diff) | |
| download | glibc-cbed6a607d6b42b0cb264d2bee1bd784c8504d60.tar.gz glibc-cbed6a607d6b42b0cb264d2bee1bd784c8504d60.tar.xz glibc-cbed6a607d6b42b0cb264d2bee1bd784c8504d60.zip | |
[BZ #5240]
* sysdeps/unix/sysv/linux/lowlevellock.c (__lll_timedlock_wait): If we time out, try one last time to lock the futex to avoid losing a wakeup signal. * sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise.
| -rw-r--r-- | nptl/ChangeLog | 7 | ||||
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S | 6 | ||||
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/lowlevellock.c | 23 | ||||
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S | 6 |
4 files changed, 29 insertions, 13 deletions
diff --git a/nptl/ChangeLog b/nptl/ChangeLog index bcec5e9651..c5019e49f1 100644 --- a/nptl/ChangeLog +++ b/nptl/ChangeLog @@ -1,5 +1,12 @@ 2007-11-08 Ulrich Drepper <drepper@redhat.com> + [BZ #5240] + * sysdeps/unix/sysv/linux/lowlevellock.c (__lll_timedlock_wait): + If we time out, try one last time to lock the futex to avoid + losing a wakeup signal. + * sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S: Likewise. + * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise. + [BZ #5245] * sysdeps/pthread/createthread.c (do_clone): Translate clone error if necessary. diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S index 745ab91239..6d3943b0eb 100644 --- a/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S +++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/lowlevellock.S @@ -203,7 +203,7 @@ __lll_timedlock_wait: addl $1000000000, %edx subl $1, %ecx 4: testl %ecx, %ecx - js 5f /* Time is already up. */ + js 9f /* Time is already up. */ /* Store relative timeout. */ movl %ecx, (%esp) @@ -271,6 +271,10 @@ __lll_timedlock_wait: 5: movl $ETIMEDOUT, %eax jmp 6b + +9: movl $-ETIMEDOUT, %ecx + movl $2, %edx + jmp 8b cfi_endproc .size __lll_timedlock_wait,.-__lll_timedlock_wait #endif diff --git a/nptl/sysdeps/unix/sysv/linux/lowlevellock.c b/nptl/sysdeps/unix/sysv/linux/lowlevellock.c index f0e42957c2..c2cdf3a1e4 100644 --- a/nptl/sysdeps/unix/sysv/linux/lowlevellock.c +++ b/nptl/sysdeps/unix/sysv/linux/lowlevellock.c @@ -59,10 +59,10 @@ __lll_timedlock_wait (int *futex, const struct timespec *abstime, int private) if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) return EINVAL; + struct timespec rt; do { struct timeval tv; - struct timespec rt; /* Get the current time. */ (void) __gettimeofday (&tv, NULL); @@ -76,18 +76,21 @@ __lll_timedlock_wait (int *futex, const struct timespec *abstime, int private) --rt.tv_sec; } - /* Already timed out? */ - if (rt.tv_sec < 0) - return ETIMEDOUT; + /* If timed out do not go to sleep. */ + if (__builtin_expect (rt.tv_sec >= 0, 1)) + { + /* Wait. */ + int oldval = atomic_compare_and_exchange_val_acq (futex, 2, 1); + if (oldval != 0) + lll_futex_timed_wait (futex, 2, &rt, private); + } - /* Wait. */ - int oldval = atomic_compare_and_exchange_val_acq (futex, 2, 1); - if (oldval != 0) - lll_futex_timed_wait (futex, 2, &rt, private); + if (atomic_compare_and_exchange_bool_acq (futex, 2, 0) == 0) + return 0; } - while (atomic_compare_and_exchange_bool_acq (futex, 2, 0) != 0); + while (rt.tv_sec >= 0); - return 0; + return ETIMEDOUT; } diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S index 7065cfac32..a5ad88c199 100644 --- a/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S +++ b/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S @@ -199,14 +199,16 @@ __lll_timedlock_wait: addq $1000000000, %rsi decq %rdi 4: testq %rdi, %rdi - js 5f /* Time is already up. */ + movq $-ETIMEDOUT, %rcx + movl $2, %edx + js 8f /* Time is already up. */ /* Futex call. */ movq %rdi, (%rsp) /* Store relative timeout. */ movq %rsi, 8(%rsp) movl $1, %eax - movl $2, %edx + /* NB: $edx has been loaded early. */ LOCK cmpxchgl %edx, (%r12) |