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Hi! While looking at IA-64 NPTL, I've noticed IA-64 LT spinlocks never worked. This patch updates them to what I have in my IA-64 NPTL tree (passes tst-spin{1,2,3} then). 2003-03-07 Jakub Jelinek <jakub at redhat dot com> * sysdeps/ia64/pspinlock.c (__pthread_spin_lock, __pthread_spin_trylock): Rewritten. --- libc/linuxthreads/sysdeps/ia64/pspinlock.c.jj 2002-08-27 17:19:43.000000000 -0400 +++ libc/linuxthreads/sysdeps/ia64/pspinlock.c 2003-03-07 04:07:42.000000000 -0500 @@ -1,5 +1,5 @@ /* POSIX spinlock implementation. ia64 version. - Copyright (C) 2000 Free Software Foundation, Inc. + Copyright (C) 2000, 2003 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Jes Sorensen <jes at linuxcare dot com> @@ -21,6 +21,7 @@ #include <errno.h> #include <pthread.h> #include "internals.h" +#include <ia64intrin.h> /* This implementation is inspired by the implementation used in the Linux kernel. */ @@ -28,21 +29,15 @@ int __pthread_spin_lock (pthread_spinlock_t *lock) { - asm volatile - ("mov ar.ccv = r0\n\t" - "mov r3 = 1\n\t" - ";;\n" - "1:\n\t" - "ld4 r2 = %0\n\t" - ";;\n\t" - "cmp4.eq p0, p7 = r0, r2\n\t" - "(p7) br.cond.spnt.few 1b \n\t" - "cmpxchg4.acq r2 = %0, r3, ar.ccv\n\t" - ";;\n\t" - "cmp4.eq p0, p7 = r0, r2\n\t" - "(p7) br.cond.spnt.few 1b\n\t" - ";;\n" - :: "m" (lock) : "r2", "r3", "p7", "memory"); + int *p = (int *) lock; + + while (__builtin_expect (__sync_val_compare_and_swap_si (p, 0, 1), 0)) + { + /* Spin without using the atomic instruction. */ + do + __asm __volatile ("" : : : "memory"); + while (*p); + } return 0; } weak_alias (__pthread_spin_lock, pthread_spin_lock) @@ -51,16 +46,7 @@ weak_alias (__pthread_spin_lock, pthread int __pthread_spin_trylock (pthread_spinlock_t *lock) { - int oldval; - - asm volatile - ("mov ar.ccv = r0\n\t" - "mov r2 = 1\n\t" - ";;\n\t" - "cmpxchg4.acq %0 = %1, r2, ar.ccv\n\t" - ";;\n" - : "=r" (oldval) : "m" (lock) : "r2", "memory"); - return oldval > 0 ? 0 : EBUSY; + return __sync_val_compare_and_swap_si ((int *) lock, 0, 1) == 0 ? 0 : EBUSY; } weak_alias (__pthread_spin_trylock, pthread_spin_trylock) Jakub
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