Upadte.

2000-04-11  Ulrich Drepper  <drepper@redhat.com>

	* internals.h: Define MEMORY_BARRIER as empty if not defined already.
	* spinlock.c (__pthread_lock): Add memory barriers.
	(__pthread_unlock): Likewise.
	* sysdeps/alpha/pt-machine.h (MEMORY_BARRIER): Define using mb
	instruction.
	(RELEASE): Not needed anymore.
	(__compare_and_swap): Mark asm as modifying memory.
	* sysdeps/powerpc/pt-machine.h (sync): Remove.  Replace with definition
	of MEMORY_BARRIER.
	(__compare_and_swap): Use MEMORY_BARRIER instead of sync.
	* sysdeps/sparc/sparc32/pt-machine.h (RELEASE): Not needed anymore.
	(MEMORY_BARRIER): Define using stbar.
	* sysdeps/sparc/sparc64/pt-machine.h (MEMORY_BARRIER): Define using
	stbar.
	(__compare_and_swap): Use MEMORY_BARRIER to ensure ordering.
	Patch by Xavier Leroy <Xavier.Leroy@inria.fr> based on comments by
	Mike Burrows <m3b@pa.dec.com>.

1 files changed, 2 insertions, 7 deletions

diff --git a/linuxthreads/sysdeps/powerpc/pt-machine.h b/linuxthreads/sysdeps/powerpc/pt-machine.h
index 578369a7fe..c7d0670d82 100644
--- a/linuxthreads/sysdeps/powerpc/pt-machine.h
+++ b/linuxthreads/sysdeps/powerpc/pt-machine.h
@@ -27,12 +27,7 @@
 
 /* For multiprocessor systems, we want to ensure all memory accesses
    are completed before we reset a lock.  */
-#if 0
-/* on non multiprocessor systems, you can just: */
-#define sync() /* nothing */
-#else
-#define sync() __asm__ __volatile__ ("sync")
-#endif
+#define MEMORY_BARRIER() __asm__ __volatile__ ("sync" : : : "memory")
 
 /* Get some notion of the current stack.  Need not be exactly the top
    of the stack, just something somewhere in the current frame.  */
@@ -64,6 +59,6 @@ __compare_and_swap (long int *p, long int oldval, long int newval)
 	: "=&r"(ret)
 	: "r"(p), "r"(newval), "r"(oldval)
 	: "cr0", "memory");
-  sync();
+  MEMORY_BARRIER();
   return ret == 0;
 }