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| author | Ulrich Drepper <drepper@redhat.com> | 2004-03-23 10:01:06 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2004-03-23 10:01:06 +0000 |
| commit | e408880b8102768b2fb612a82589a143b04d6302 (patch) | |
| tree | d26a78a852532cd39bf83212f025a2a5b7659dc5 /nptl | |
| parent | 16b06b70b58461cca36a4aa83559cb89385076ce (diff) | |
| download | glibc-e408880b8102768b2fb612a82589a143b04d6302.zip glibc-e408880b8102768b2fb612a82589a143b04d6302.tar.gz glibc-e408880b8102768b2fb612a82589a143b04d6302.tar.bz2 | |
Update.
2004-03-23 Ulrich Drepper <drepper@redhat.com>
* sysdeps/ia64/pt-machine.h (BUSY_WAIT_NOP): Define.
* sysdeps/x86_64/pt-machine.h (BUSY_WAIT_NOP): Likewise.
Diffstat (limited to 'nptl')
| -rw-r--r-- | nptl/ChangeLog | 3 | ||||
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h | 7 |
2 files changed, 9 insertions, 1 deletions
diff --git a/nptl/ChangeLog b/nptl/ChangeLog index e0439e1..5155b79 100644 --- a/nptl/ChangeLog +++ b/nptl/ChangeLog @@ -1,6 +1,9 @@ 2004-03-23 Ulrich Drepper <drepper@redhat.com> * sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_mutex_trylock): + No need to restrict type of ret. Make it int. Add comment. + + * sysdeps/unix/sysv/linux/i386/lowlevellock.h (lll_mutex_trylock): Remove unnecessary setne instruction. 2004-03-22 Jakub Jelinek <jakub@redhat.com> diff --git a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h index 9f089f8..a9823d8 100644 --- a/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h +++ b/nptl/sysdeps/unix/sysv/linux/i386/lowlevellock.h @@ -102,8 +102,13 @@ extern int __lll_mutex_unlock_wake (int *__futex) __attribute ((regparm (1))) attribute_hidden; +/* NB: in the lll_mutex_trylock macro we simply return the value in %eax + after the cmpxchg instruction. In case the operation succeded this + value is zero. In case the operation failed, the cmpxchg instruction + has loaded the current value of the memory work which is guaranteed + to be nonzero. */ #define lll_mutex_trylock(futex) \ - ({ unsigned char ret; \ + ({ int ret; \ __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \ : "=a" (ret), "=m" (futex) \ : "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\ |