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author | Ulrich Drepper <drepper@redhat.com> | 2003-03-11 05:52:12 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 2003-03-11 05:52:12 +0000 |
commit | 6a4263e3d5a6fee74776f3bcad4e53f5257aa5bf (patch) | |
tree | d40ee1bc4a17499cd489c58a66d9d0c0ce1b1658 /nptl/sysdeps/unix/sysv/linux/x86_64 | |
parent | 3de7c2a96526ff7344152c887845c11b35e301e6 (diff) | |
download | glibc-6a4263e3d5a6fee74776f3bcad4e53f5257aa5bf.tar.gz glibc-6a4263e3d5a6fee74776f3bcad4e53f5257aa5bf.tar.xz glibc-6a4263e3d5a6fee74776f3bcad4e53f5257aa5bf.zip |
Update.
* sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S: New file * sysdeps/unix/sysv/linux/sh/pthread_barrier_wait.S: Likewise.
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/x86_64')
-rw-r--r-- | nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S new file mode 100644 index 0000000000..c4ee4dbc08 --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S @@ -0,0 +1,126 @@ +/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sysdep.h> +#include <lowlevelbarrier.h> + +#define SYS_futex 202 +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + +#ifndef UP +# define LOCK lock +#else +# define LOCK +#endif + + + .text + + .globl pthread_barrier_wait + .type pthread_barrier_wait,@function + .align 16 +pthread_barrier_wait: + /* Get the mutex. */ + orl $-1, %esi + LOCK + xaddl %esi, MUTEX(%rdi) + jne 1f + + /* One less waiter. If this was the last one needed wake + everybody. */ +2: decl LEFT(%rdi) + je 3f + + /* There are more threads to come. */ +#if CURR_EVENT == 0 + movl (%rdi), %edx +#else + movl CURR_EVENT(%rdi), %edx +#endif + + /* Release the mutex. */ + LOCK + addl $1, MUTEX(%rdi) + jng 6f + + /* Wait for the remaining threads. The call will return immediately + if the CURR_EVENT memory has meanwhile been changed. */ +7: xorq %rsi, %rsi /* movl $FUTEX_WAIT, %ecx */ + xorq %r10, %r10 +8: movq $SYS_futex, %rax + syscall + + /* Don't return on spurious wakeups. The syscall does not change + any register except %eax so there is no need to reload any of + them. */ +#if CURR_EVENT == 0 + cmpl %edx, (%rdi) +#else + cmpl %edx, CURR_EVENT(%rdi) +#endif + je 8b + + /* Note: %esi is still zero. */ + movl %esi, %eax /* != PTHREAD_BARRIER_SERIAL_THREAD */ + + retq + + /* The necessary number of threads arrived. */ +3: movl INIT_COUNT(%rdi), %eax + movl %eax, LEFT(%rdi) +#if CURR_EVENT == 0 + incl (%rdi) +#else + incl CURR_EVENT(%rdi) +#endif + + /* Wake up all waiters. The count is a signed number in the kernel + so 0x7fffffff is the highest value. */ + movl $0x7fffffff, %edx + movq $FUTEX_WAKE, %rsi + movq $SYS_futex, %rax + syscall + + /* 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 + addl $1, MUTEX(%rdi) + jng 4f + +5: orl $-1, %eax /* == PTHREAD_BARRIER_SERIAL_THREAD */ + + retq + +1: addq $MUTEX, %rdi + call __lll_lock_wait + subq $MUTEX, %rdi + jmp 2b + +4: addq $MUTEX, %rdi + call __lll_unlock_wake + subq $MUTEX, %rdi + jmp 5b + +6: addq $MUTEX, %rdi + call __lll_unlock_wake + subq $MUTEX, %rdi + jmp 7b + .size pthread_barrier_wait,.-pthread_barrier_wait |