diff options
| author | Ulrich Drepper <drepper@redhat.com> | 2004-02-19 04:10:16 +0000 |
|---|---|---|
| committer | Ulrich Drepper <drepper@redhat.com> | 2004-02-19 04:10:16 +0000 |
| commit | 37c054c7c4a969816d2bc3c8284bdcadf68ebeec (patch) | |
| tree | ec0a8cc53830ddb66445be30615fd15b894495fa /nptl/sysdeps/unix/sysv/linux/i386/i486 | |
| parent | dc39124662b25ce2db28454f1749d67550e4de31 (diff) | |
Update.
* sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S
(pthread_barrier_wait): After wakeup, release lock only when the
last thread stopped using the barrier object.
* sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S
(pthread_barrier_wait): Likewise.
* sysdeps/pthread/pthread_barrier_wait.c (pthread_barrier_wait):
Likewise.
* Makefile (tests): Add tst-barrier4.
* tst-barrier4.c: New file.
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/i386/i486')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S | 38 |
1 files changed, 34 insertions, 4 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S index d4b61a10c1..114284c44c 100644 --- a/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S +++ b/nptl/sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S @@ -1,4 +1,4 @@ -/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. +/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. @@ -84,16 +84,32 @@ pthread_barrier_wait: #endif je,pn 8b + /* Increment LEFT. If this brings the count back to the + initial count unlock the object. */ + movl $1, %edx + movl INIT_COUNT(%ebx), %ecx + LOCK + xaddl %edx, LEFT(%ebx) + subl $1, %ecx + cmpl %ecx, %edx + jne,pt 10f + + /* Release the mutex. We cannot release the lock before + waking the waiting threads since otherwise a new thread might + arrive and gets waken up, too. */ + LOCK + subl $1, MUTEX(%ebx) + jne 9f + /* Note: %esi is still zero. */ - movl %esi, %eax /* != PTHREAD_BARRIER_SERIAL_THREAD */ +10: movl %esi, %eax /* != PTHREAD_BARRIER_SERIAL_THREAD */ popl %esi popl %ebx ret /* The necessary number of threads arrived. */ -3: movl INIT_COUNT(%ebx), %eax - movl %eax, LEFT(%ebx) +3: #if CURR_EVENT == 0 addl $1, (%ebx) #else @@ -107,6 +123,16 @@ pthread_barrier_wait: movl $SYS_futex, %eax ENTER_KERNEL + /* Increment LEFT. If this brings the count back to the + initial count unlock the object. */ + movl $1, %edx + movl INIT_COUNT(%ebx), %ecx + LOCK + xaddl %edx, LEFT(%ebx) + subl $1, %ecx + cmpl %ecx, %edx + jne,pt 5f + /* Release the mutex. We cannot release the lock before waking the waiting threads since otherwise a new thread might arrive and gets waken up, too. */ @@ -130,4 +156,8 @@ pthread_barrier_wait: 6: leal MUTEX(%ebx), %eax call __lll_mutex_unlock_wake jmp 7b + +9: leal MUTEX(%ebx), %eax + call __lll_mutex_unlock_wake + jmp 10b .size pthread_barrier_wait,.-pthread_barrier_wait |