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Fw: [PATCH]: Fix sparc atomic operations


Ping?
--- Begin Message ---
The sparc atomics were missing "memory" clobbers in their
asm statements.  This caused miscompilation of the various
pthread atomic primitives.

In one case, pthread_mutex_lock() was miscompiled such that
the ->owner field of the mutex was sampled before we acquired
the lock, thus triggering the "owner == 0" assertion if things
were just right.

Surprisingly nothing in the nptl tests caught this, instead I
discovered it when trying to build MONO, which seemed to be
able to trigger this case quite readily. :-)

Please apply, thanks.

2006-03-24  David S. Miller  <davem@sunset.davemloft.net>

	* sysdeps/sparc/sparc32/bits/atomic.h
	(__v9_compare_and_exchange_val_32_acq): Add "memory" clobber.
	* sysdeps/sparc/sparc32/sparcv9/bits/atomic.h
	(__arch_compare_and_exchange_val_32_acq, atomic_exchange_acq):
	Likewise.
	* sysdeps/sparc/sparc64/bits/atomic.h
	(__arch_compare_and_exchange_val_32_acq,
	__arch_compare_and_exchange_val_64_acq, atomic_exchange_acq):
	Likewise.
	
--- ./sysdeps/sparc/sparc32/bits/atomic.h.~1~	2006-01-03 16:05:07.000000000 -0800
+++ ./sysdeps/sparc/sparc32/bits/atomic.h	2006-03-24 00:00:06.000000000 -0800
@@ -122,7 +122,7 @@ volatile unsigned char __sparc32_atomic_
   __asm __volatile (".word 0xcde05005"					      \
 		    : "+r" (__acev_tmp), "=m" (*__acev_mem)		      \
 		    : "r" (__acev_oldval), "m" (*__acev_mem),		      \
-		      "r" (__acev_mem));				      \
+		      "r" (__acev_mem) : "memory");			      \
   __acev_tmp; })
 #endif
 
--- ./sysdeps/sparc/sparc32/sparcv9/bits/atomic.h.~1~	2006-01-03 16:05:07.000000000 -0800
+++ ./sysdeps/sparc/sparc32/sparcv9/bits/atomic.h	2006-03-24 00:00:32.000000000 -0800
@@ -59,7 +59,7 @@ typedef uintmax_t uatomic_max_t;
   __asm __volatile ("cas [%4], %2, %0"					      \
 		    : "=r" (__acev_tmp), "=m" (*__acev_mem)		      \
 		    : "r" (oldval), "m" (*__acev_mem), "r" (__acev_mem),      \
-		      "0" (newval));					      \
+		      "0" (newval) : "memory");				      \
   __acev_tmp; })
 
 /* This can be implemented if needed.  */
@@ -74,7 +74,7 @@ typedef uintmax_t uatomic_max_t;
      if (sizeof (*(mem)) == 4)						      \
        __asm ("swap %0, %1"						      \
 	      : "=m" (*__memp), "=r" (__oldval)				      \
-	      : "m" (*__memp), "1" (__value));				      \
+	      : "m" (*__memp), "1" (__value) : "memory");		      \
      else								      \
        abort ();							      \
      __oldval; })
--- ./sysdeps/sparc/sparc64/bits/atomic.h.~1~	2006-01-03 16:05:07.000000000 -0800
+++ ./sysdeps/sparc/sparc64/bits/atomic.h	2006-03-24 00:01:04.000000000 -0800
@@ -59,7 +59,7 @@ typedef uintmax_t uatomic_max_t;
   __asm __volatile ("cas [%4], %2, %0"					      \
 		    : "=r" (__acev_tmp), "=m" (*__acev_mem)		      \
 		    : "r" (oldval), "m" (*__acev_mem), "r" (__acev_mem),      \
-		      "0" (newval));					      \
+		      "0" (newval) : "memory");				      \
   __acev_tmp; })
 
 #define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \
@@ -69,7 +69,7 @@ typedef uintmax_t uatomic_max_t;
   __asm __volatile ("casx [%4], %2, %0"					      \
 		    : "=r" (__acev_tmp), "=m" (*__acev_mem)		      \
 		    : "r" ((long) (oldval)), "m" (*__acev_mem),		      \
-		      "r" (__acev_mem), "0" ((long) (newval)));		      \
+		      "r" (__acev_mem), "0" ((long) (newval)) : "memory");    \
   __acev_tmp; })
 
 #define atomic_exchange_acq(mem, newvalue) \
@@ -80,7 +80,7 @@ typedef uintmax_t uatomic_max_t;
      if (sizeof (*(mem)) == 4)						      \
        __asm ("swap %0, %1"						      \
 	      : "=m" (*__memp), "=r" (__oldval)				      \
-	      : "m" (*__memp), "1" (__value));				      \
+	      : "m" (*__memp), "1" (__value) : "memory");		      \
      else								      \
        {								      \
 	 __val = *__memp;						      \

--- End Message ---

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