[SPARC64]: Avoid membar instructions in delay slots.

In particular, avoid membar instructions in the delay
slot of a jmpl instruction.

UltraSPARC-I, II, IIi, and IIe have a bug, documented in
the UltraSPARC-IIi User's Manual, Appendix K, Erratum 51

The long and short of it is that if the IMU unit misses
on a branch or jmpl, and there is a store buffer synchronizing
membar in the delay slot, the chip can stop fetching instructions.

If interrupts are enabled or some other trap is enabled, the
chip will unwedge itself, but performance will suffer.

We already had a workaround for this bug in a few spots, but
it's better to have the entire tree sanitized for this rule.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc64/kernel/entry.S

@@ -271,8 +271,9 @@ cplus_fptrap_insn_1:
 	fmuld		%f0, %f2, %f26
 	faddd		%f0, %f2, %f28
 	fmuld		%f0, %f2, %f30
-	b,pt		%xcc, fpdis_exit
 	membar		#Sync
+	b,pt		%xcc, fpdis_exit
+	 nop
 2:	andcc		%g5, FPRS_DU, %g0
 	bne,pt		%icc, 3f
 	 fzero		%f32
@@ -301,8 +302,9 @@ cplus_fptrap_insn_2:
 	fmuld		%f32, %f34, %f58
 	faddd		%f32, %f34, %f60
 	fmuld		%f32, %f34, %f62
-	ba,pt		%xcc, fpdis_exit
 	membar		#Sync
+	ba,pt		%xcc, fpdis_exit
+	 nop
 3:	mov		SECONDARY_CONTEXT, %g3
 	add		%g6, TI_FPREGS, %g1
 	ldxa		[%g3] ASI_DMMU, %g5

arch/sparc64/kernel/semaphore.c

@@ -32,8 +32,9 @@ static __inline__ int __sem_update_count(struct semaphore *sem, int incr)
 "	add	%1, %4, %1\n"
 "	cas	[%3], %0, %1\n"
 "	cmp	%0, %1\n"
-"	bne,pn	%%icc, 1b\n"
 "	membar	#StoreLoad | #StoreStore\n"
+"	bne,pn	%%icc, 1b\n"
+"	 nop\n"
 	: "=&r" (old_count), "=&r" (tmp), "=m" (sem->count)
 	: "r" (&sem->count), "r" (incr), "m" (sem->count)
 	: "cc");
@@ -71,8 +72,9 @@ void up(struct semaphore *sem)
 "	cmp	%%g1, %%g7\n"
 "	bne,pn	%%icc, 1b\n"
 "	 addcc	%%g7, 1, %%g0\n"
-"	ble,pn	%%icc, 3f\n"
 "	membar	#StoreLoad | #StoreStore\n"
+"	ble,pn	%%icc, 3f\n"
+"	 nop\n"
 "2:\n"
 "	.subsection 2\n"
 "3:	mov	%0, %%g1\n"
@@ -128,8 +130,9 @@ void __sched down(struct semaphore *sem)
 "	cmp	%%g1, %%g7\n"
 "	bne,pn	%%icc, 1b\n"
 "	 cmp	%%g7, 1\n"
-"	bl,pn	%%icc, 3f\n"
 "	membar	#StoreLoad | #StoreStore\n"
+"	bl,pn	%%icc, 3f\n"
+"	 nop\n"
 "2:\n"
 "	.subsection 2\n"
 "3:	mov	%0, %%g1\n"
@@ -233,8 +236,9 @@ int __sched down_interruptible(struct semaphore *sem)
 "	cmp	%%g1, %%g7\n"
 "	bne,pn	%%icc, 1b\n"
 "	 cmp	%%g7, 1\n"
-"	bl,pn	%%icc, 3f\n"
 "	membar	#StoreLoad | #StoreStore\n"
+"	bl,pn	%%icc, 3f\n"
+"	 nop\n"
 "2:\n"
 "	.subsection 2\n"
 "3:	mov	%2, %%g1\n"

arch/sparc64/kernel/trampoline.S

@@ -98,8 +98,9 @@ startup_continue:
 
 	sethi		%hi(prom_entry_lock), %g2
 1:	ldstub		[%g2 + %lo(prom_entry_lock)], %g1
-	brnz,pn		%g1, 1b
 	membar		#StoreLoad | #StoreStore
+	brnz,pn		%g1, 1b
+	 nop
 
 	sethi		%hi(p1275buf), %g2
 	or		%g2, %lo(p1275buf), %g2

arch/sparc64/lib/U1memcpy.S

@@ -87,14 +87,17 @@
 #define LOOP_CHUNK3(src, dest, len, branch_dest)		\
 	MAIN_LOOP_CHUNK(src, dest, f32, f48, len, branch_dest)
 
+#define DO_SYNC			membar	#Sync;
 #define STORE_SYNC(dest, fsrc)				\
 	EX_ST(STORE_BLK(%fsrc, %dest));			\
-	add			%dest, 0x40, %dest;
+	add			%dest, 0x40, %dest;	\
+	DO_SYNC
 
 #define STORE_JUMP(dest, fsrc, target)			\
 	EX_ST(STORE_BLK(%fsrc, %dest));			\
 	add			%dest, 0x40, %dest;	\
-	ba,pt			%xcc, target;
+	ba,pt			%xcc, target;		\
+	 nop;
 
 #define FINISH_VISCHUNK(dest, f0, f1, left)	\
 	subcc			%left, 8, %left;\
@@ -239,17 +242,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f0, %f2, %f48
 1:	FREG_FROB(f16,f18,f20,f22,f24,f26,f28,f30,f32)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f32,f34,f36,f38,f40,f42,f44,f46,f0)
-	STORE_JUMP(o0, f48, 40f) membar #Sync
+	STORE_JUMP(o0, f48, 40f)
 2:	FREG_FROB(f32,f34,f36,f38,f40,f42,f44,f46,f0)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f0, f2, f4, f6, f8, f10,f12,f14,f16)
-	STORE_JUMP(o0, f48, 48f) membar #Sync
+	STORE_JUMP(o0, f48, 48f)
 3:	FREG_FROB(f0, f2, f4, f6, f8, f10,f12,f14,f16)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f16,f18,f20,f22,f24,f26,f28,f30,f32)
-	STORE_JUMP(o0, f48, 56f) membar #Sync
+	STORE_JUMP(o0, f48, 56f)
 
 1:	FREG_FROB(f2, f4, f6, f8, f10,f12,f14,f16,f18)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -260,17 +263,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f2, %f4, %f48
 1:	FREG_FROB(f18,f20,f22,f24,f26,f28,f30,f32,f34)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f34,f36,f38,f40,f42,f44,f46,f0, f2)
-	STORE_JUMP(o0, f48, 41f) membar #Sync
+	STORE_JUMP(o0, f48, 41f)
 2:	FREG_FROB(f34,f36,f38,f40,f42,f44,f46,f0, f2)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f2, f4, f6, f8, f10,f12,f14,f16,f18)
-	STORE_JUMP(o0, f48, 49f) membar #Sync
+	STORE_JUMP(o0, f48, 49f)
 3:	FREG_FROB(f2, f4, f6, f8, f10,f12,f14,f16,f18)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f18,f20,f22,f24,f26,f28,f30,f32,f34)
-	STORE_JUMP(o0, f48, 57f) membar #Sync
+	STORE_JUMP(o0, f48, 57f)
 
 1:	FREG_FROB(f4, f6, f8, f10,f12,f14,f16,f18,f20)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -281,17 +284,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f4, %f6, %f48
 1:	FREG_FROB(f20,f22,f24,f26,f28,f30,f32,f34,f36)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f36,f38,f40,f42,f44,f46,f0, f2, f4)
-	STORE_JUMP(o0, f48, 42f) membar #Sync
+	STORE_JUMP(o0, f48, 42f)
 2:	FREG_FROB(f36,f38,f40,f42,f44,f46,f0, f2, f4)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f4, f6, f8, f10,f12,f14,f16,f18,f20)
-	STORE_JUMP(o0, f48, 50f) membar #Sync
+	STORE_JUMP(o0, f48, 50f)
 3:	FREG_FROB(f4, f6, f8, f10,f12,f14,f16,f18,f20)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f20,f22,f24,f26,f28,f30,f32,f34,f36)
-	STORE_JUMP(o0, f48, 58f) membar #Sync
+	STORE_JUMP(o0, f48, 58f)
 
 1:	FREG_FROB(f6, f8, f10,f12,f14,f16,f18,f20,f22)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -302,17 +305,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f6, %f8, %f48
 1:	FREG_FROB(f22,f24,f26,f28,f30,f32,f34,f36,f38)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f38,f40,f42,f44,f46,f0, f2, f4, f6)
-	STORE_JUMP(o0, f48, 43f) membar #Sync
+	STORE_JUMP(o0, f48, 43f)
 2:	FREG_FROB(f38,f40,f42,f44,f46,f0, f2, f4, f6)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f6, f8, f10,f12,f14,f16,f18,f20,f22)
-	STORE_JUMP(o0, f48, 51f) membar #Sync
+	STORE_JUMP(o0, f48, 51f)
 3:	FREG_FROB(f6, f8, f10,f12,f14,f16,f18,f20,f22)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f22,f24,f26,f28,f30,f32,f34,f36,f38)
-	STORE_JUMP(o0, f48, 59f) membar #Sync
+	STORE_JUMP(o0, f48, 59f)
 
 1:	FREG_FROB(f8, f10,f12,f14,f16,f18,f20,f22,f24)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -323,17 +326,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f8, %f10, %f48
 1:	FREG_FROB(f24,f26,f28,f30,f32,f34,f36,f38,f40)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f40,f42,f44,f46,f0, f2, f4, f6, f8)
-	STORE_JUMP(o0, f48, 44f) membar #Sync
+	STORE_JUMP(o0, f48, 44f)
 2:	FREG_FROB(f40,f42,f44,f46,f0, f2, f4, f6, f8)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f8, f10,f12,f14,f16,f18,f20,f22,f24)
-	STORE_JUMP(o0, f48, 52f) membar #Sync
+	STORE_JUMP(o0, f48, 52f)
 3:	FREG_FROB(f8, f10,f12,f14,f16,f18,f20,f22,f24)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f24,f26,f28,f30,f32,f34,f36,f38,f40)
-	STORE_JUMP(o0, f48, 60f) membar #Sync
+	STORE_JUMP(o0, f48, 60f)
 
 1:	FREG_FROB(f10,f12,f14,f16,f18,f20,f22,f24,f26)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -344,17 +347,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f10, %f12, %f48
 1:	FREG_FROB(f26,f28,f30,f32,f34,f36,f38,f40,f42)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f42,f44,f46,f0, f2, f4, f6, f8, f10)
-	STORE_JUMP(o0, f48, 45f) membar #Sync
+	STORE_JUMP(o0, f48, 45f)
 2:	FREG_FROB(f42,f44,f46,f0, f2, f4, f6, f8, f10)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f10,f12,f14,f16,f18,f20,f22,f24,f26)
-	STORE_JUMP(o0, f48, 53f) membar #Sync
+	STORE_JUMP(o0, f48, 53f)
 3:	FREG_FROB(f10,f12,f14,f16,f18,f20,f22,f24,f26)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f26,f28,f30,f32,f34,f36,f38,f40,f42)
-	STORE_JUMP(o0, f48, 61f) membar #Sync
+	STORE_JUMP(o0, f48, 61f)
 
 1:	FREG_FROB(f12,f14,f16,f18,f20,f22,f24,f26,f28)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -365,17 +368,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f12, %f14, %f48
 1:	FREG_FROB(f28,f30,f32,f34,f36,f38,f40,f42,f44)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f44,f46,f0, f2, f4, f6, f8, f10,f12)
-	STORE_JUMP(o0, f48, 46f) membar #Sync
+	STORE_JUMP(o0, f48, 46f)
 2:	FREG_FROB(f44,f46,f0, f2, f4, f6, f8, f10,f12)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f12,f14,f16,f18,f20,f22,f24,f26,f28)
-	STORE_JUMP(o0, f48, 54f) membar #Sync
+	STORE_JUMP(o0, f48, 54f)
 3:	FREG_FROB(f12,f14,f16,f18,f20,f22,f24,f26,f28)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f28,f30,f32,f34,f36,f38,f40,f42,f44)
-	STORE_JUMP(o0, f48, 62f) membar #Sync
+	STORE_JUMP(o0, f48, 62f)
 
 1:	FREG_FROB(f14,f16,f18,f20,f22,f24,f26,f28,f30)
 	LOOP_CHUNK1(o1, o0, GLOBAL_SPARE, 1f)
@@ -386,17 +389,17 @@ FUNC_NAME:		/* %o0=dst, %o1=src, %o2=len */
 	ba,pt		%xcc, 1b+4
 	 faligndata	%f14, %f16, %f48
 1:	FREG_FROB(f30,f32,f34,f36,f38,f40,f42,f44,f46)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f46,f0, f2, f4, f6, f8, f10,f12,f14)
-	STORE_JUMP(o0, f48, 47f) membar #Sync
+	STORE_JUMP(o0, f48, 47f)
 2:	FREG_FROB(f46,f0, f2, f4, f6, f8, f10,f12,f14)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f14,f16,f18,f20,f22,f24,f26,f28,f30)
-	STORE_JUMP(o0, f48, 55f) membar #Sync
+	STORE_JUMP(o0, f48, 55f)
 3:	FREG_FROB(f14,f16,f18,f20,f22,f24,f26,f28,f30)
-	STORE_SYNC(o0, f48) membar #Sync
+	STORE_SYNC(o0, f48)
 	FREG_FROB(f30,f32,f34,f36,f38,f40,f42,f44,f46)
-	STORE_JUMP(o0, f48, 63f) membar #Sync
+	STORE_JUMP(o0, f48, 63f)
 
 40:	FINISH_VISCHUNK(o0, f0,  f2,  g3)
 41:	FINISH_VISCHUNK(o0, f2,  f4,  g3)

arch/sparc64/lib/VISsave.S

@@ -72,7 +72,11 @@ vis1:	ldub		[%g6 + TI_FPSAVED], %g3
 
 	stda		%f48, [%g3 + %g1] ASI_BLK_P
 5:	membar		#Sync
-	jmpl		%g7 + %g0, %g0
+	ba,pt		%xcc, 80f
+	 nop
+
+	.align		32
+80:	jmpl		%g7 + %g0, %g0
 	 nop
 
 6:	ldub		[%g3 + TI_FPSAVED], %o5
@@ -87,8 +91,11 @@ vis1:	ldub		[%g6 + TI_FPSAVED], %g3
 	stda		%f32, [%g2 + %g1] ASI_BLK_P
 	stda		%f48, [%g3 + %g1] ASI_BLK_P
 	membar		#Sync
-	jmpl		%g7 + %g0, %g0
+	ba,pt		%xcc, 80f
+	 nop
 
+	.align		32
+80:	jmpl		%g7 + %g0, %g0
 	 nop
 
 	.align		32
@@ -126,6 +133,10 @@ VISenterhalf:
 	stda		%f0, [%g2 + %g1] ASI_BLK_P
 	stda		%f16, [%g3 + %g1] ASI_BLK_P
 	membar		#Sync
+	ba,pt		%xcc, 4f
+	 nop
+
+	.align		32
 4:	and		%o5, FPRS_DU, %o5
 	jmpl		%g7 + %g0, %g0
 	 wr		%o5, FPRS_FEF, %fprs

arch/sparc64/lib/atomic.S

@@ -7,18 +7,6 @@
 #include <linux/config.h>
 #include <asm/asi.h>
 
-	/* On SMP we need to use memory barriers to ensure
-	 * correct memory operation ordering, nop these out
-	 * for uniprocessor.
-	 */
-#ifdef CONFIG_SMP
-#define ATOMIC_PRE_BARRIER	membar #StoreLoad | #LoadLoad
-#define ATOMIC_POST_BARRIER	membar #StoreLoad | #StoreStore
-#else
-#define ATOMIC_PRE_BARRIER	nop
-#define ATOMIC_POST_BARRIER	nop
-#endif
-
 	.text
 
 	/* Two versions of the atomic routines, one that
@@ -52,6 +40,24 @@ atomic_sub: /* %o0 = decrement, %o1 = atomic_ptr */
 	 nop
 	.size	atomic_sub, .-atomic_sub
 
+	/* On SMP we need to use memory barriers to ensure
+	 * correct memory operation ordering, nop these out
+	 * for uniprocessor.
+	 */
+#ifdef CONFIG_SMP
+
+#define ATOMIC_PRE_BARRIER	membar #StoreLoad | #LoadLoad;
+#define ATOMIC_POST_BARRIER	\
+	ba,pt %xcc, 80b;	\
+	membar #StoreLoad | #StoreStore
+
+80:	retl
+	 nop
+#else
+#define ATOMIC_PRE_BARRIER
+#define ATOMIC_POST_BARRIER
+#endif
+
 	.globl	atomic_add_ret
 	.type	atomic_add_ret,#function
 atomic_add_ret: /* %o0 = increment, %o1 = atomic_ptr */
@@ -62,9 +68,10 @@ atomic_add_ret: /* %o0 = increment, %o1 = atomic_ptr */
 	cmp	%g1, %g7
 	bne,pn	%icc, 1b
 	 add	%g7, %o0, %g7
+	sra	%g7, 0, %o0
 	ATOMIC_POST_BARRIER
 	retl
-	 sra	%g7, 0, %o0
+	 nop
 	.size	atomic_add_ret, .-atomic_add_ret
 
 	.globl	atomic_sub_ret
@@ -77,9 +84,10 @@ atomic_sub_ret: /* %o0 = decrement, %o1 = atomic_ptr */
 	cmp	%g1, %g7
 	bne,pn	%icc, 1b
 	 sub	%g7, %o0, %g7
+	sra	%g7, 0, %o0
 	ATOMIC_POST_BARRIER
 	retl
-	 sra	%g7, 0, %o0
+	 nop
 	.size	atomic_sub_ret, .-atomic_sub_ret
 
 	.globl	atomic64_add
@@ -118,9 +126,10 @@ atomic64_add_ret: /* %o0 = increment, %o1 = atomic_ptr */
 	cmp	%g1, %g7
 	bne,pn	%xcc, 1b
 	 add	%g7, %o0, %g7
+	mov	%g7, %o0
 	ATOMIC_POST_BARRIER
 	retl
-	 mov	%g7, %o0
+	 nop
 	.size	atomic64_add_ret, .-atomic64_add_ret
 
 	.globl	atomic64_sub_ret
@@ -133,7 +142,8 @@ atomic64_sub_ret: /* %o0 = decrement, %o1 = atomic_ptr */
 	cmp	%g1, %g7
 	bne,pn	%xcc, 1b
 	 sub	%g7, %o0, %g7
+	mov	%g7, %o0
 	ATOMIC_POST_BARRIER
 	retl
-	 mov	%g7, %o0
+	 nop
 	.size	atomic64_sub_ret, .-atomic64_sub_ret

arch/sparc64/lib/bitops.S

@@ -7,20 +7,26 @@
 #include <linux/config.h>
 #include <asm/asi.h>
 
+	.text
+
 	/* On SMP we need to use memory barriers to ensure
 	 * correct memory operation ordering, nop these out
 	 * for uniprocessor.
 	 */
+
 #ifdef CONFIG_SMP
 #define BITOP_PRE_BARRIER	membar #StoreLoad | #LoadLoad
-#define BITOP_POST_BARRIER	membar #StoreLoad | #StoreStore
+#define BITOP_POST_BARRIER	\
+	ba,pt	%xcc, 80b;	\
+	membar #StoreLoad | #StoreStore
+
+80:	retl
+	 nop
 #else
-#define BITOP_PRE_BARRIER	nop
-#define BITOP_POST_BARRIER	nop
+#define BITOP_PRE_BARRIER
+#define BITOP_POST_BARRIER
 #endif
 
-	.text
-
 	.globl	test_and_set_bit
 	.type	test_and_set_bit,#function
 test_and_set_bit:	/* %o0=nr, %o1=addr */
@@ -37,10 +43,11 @@ test_and_set_bit:	/* %o0=nr, %o1=addr */
 	cmp	%g7, %g1
 	bne,pn	%xcc, 1b
 	 and	%g7, %o2, %g2
-	BITOP_POST_BARRIER
 	clr	%o0
-	retl
 	movrne	%g2, 1, %o0
+	BITOP_POST_BARRIER
+	retl
+	 nop
 	.size	test_and_set_bit, .-test_and_set_bit
 
 	.globl	test_and_clear_bit
@@ -59,10 +66,11 @@ test_and_clear_bit:	/* %o0=nr, %o1=addr */
 	cmp	%g7, %g1
 	bne,pn	%xcc, 1b
 	 and	%g7, %o2, %g2
-	BITOP_POST_BARRIER
 	clr	%o0
-	retl
 	movrne	%g2, 1, %o0
+	BITOP_POST_BARRIER
+	retl
+	 nop
 	.size	test_and_clear_bit, .-test_and_clear_bit
 
 	.globl	test_and_change_bit
@@ -81,10 +89,11 @@ test_and_change_bit:	/* %o0=nr, %o1=addr */
 	cmp	%g7, %g1
 	bne,pn	%xcc, 1b
 	 and	%g7, %o2, %g2
-	BITOP_POST_BARRIER
 	clr	%o0
-	retl
 	movrne	%g2, 1, %o0
+	BITOP_POST_BARRIER
+	retl
+	 nop
 	.size	test_and_change_bit, .-test_and_change_bit
 
 	.globl	set_bit

arch/sparc64/lib/debuglocks.c

@@ -252,8 +252,9 @@ void _do_write_lock (rwlock_t *rw, char *str)
 "		andn	%%g1, %%g3, %%g7\n"
 "		casx	[%0], %%g1, %%g7\n"
 "		cmp	%%g1, %%g7\n"
+"		membar	#StoreLoad | #StoreStore\n"
 "		bne,pn	%%xcc, 1b\n"
-"		 membar	#StoreLoad | #StoreStore"
+"		 nop"
 		: /* no outputs */
 		: "r" (&(rw->lock))
 		: "g3", "g1", "g7", "cc", "memory");
@@ -351,8 +352,9 @@ int _do_write_trylock (rwlock_t *rw, char *str)
 "		andn	%%g1, %%g3, %%g7\n"
 "		casx	[%0], %%g1, %%g7\n"
 "		cmp	%%g1, %%g7\n"
+"		membar	#StoreLoad | #StoreStore\n"
 "		bne,pn	%%xcc, 1b\n"
-"		 membar	#StoreLoad | #StoreStore"
+"		 nop"
 		: /* no outputs */
 		: "r" (&(rw->lock))
 		: "g3", "g1", "g7", "cc", "memory");

arch/sparc64/lib/dec_and_lock.S

@@ -48,8 +48,9 @@ start_to_zero:
 #endif
 to_zero:
 	ldstub	[%o1], %g3
-	brnz,pn	%g3, spin_on_lock
 	membar	#StoreLoad | #StoreStore
+	brnz,pn	%g3, spin_on_lock
+	 nop
 loop2:	cas	[%o0], %g2, %g7		/* ASSERT(g7 == 0) */
 	cmp	%g2, %g7
 
@@ -71,8 +72,9 @@ loop2:	cas	[%o0], %g2, %g7		/* ASSERT(g7 == 0) */
 	 nop
 spin_on_lock:
 	ldub	[%o1], %g3
-	brnz,pt	%g3, spin_on_lock
 	membar	#LoadLoad
+	brnz,pt	%g3, spin_on_lock
+	 nop
 	ba,pt	%xcc, to_zero
 	 nop
 	nop

arch/sparc64/lib/rwsem.S

@@ -17,8 +17,9 @@ __down_read:
 	bne,pn		%icc, 1b
 	 add		%g7, 1, %g7
 	cmp		%g7, 0
-	bl,pn		%icc, 3f
 	membar		#StoreLoad | #StoreStore
+	bl,pn		%icc, 3f
+	 nop
 2:
 	retl
 	 nop
@@ -57,8 +58,9 @@ __down_write:
 	cmp		%g3, %g7
 	bne,pn		%icc, 1b
 	 cmp		%g7, 0
-	bne,pn		%icc, 3f
 	membar		#StoreLoad | #StoreStore
+	bne,pn		%icc, 3f
+	 nop
 2:	retl
 	 nop
 3:
@@ -97,8 +99,9 @@ __up_read:
 	cmp		%g1, %g7
 	bne,pn		%icc, 1b
 	 cmp		%g7, 0
-	bl,pn		%icc, 3f
 	membar		#StoreLoad | #StoreStore
+	bl,pn		%icc, 3f
+	 nop
 2:	retl
 	 nop
 3:	sethi		%hi(RWSEM_ACTIVE_MASK), %g1
@@ -126,8 +129,9 @@ __up_write:
 	bne,pn		%icc, 1b
 	 sub		%g7, %g1, %g7
 	cmp		%g7, 0
-	bl,pn		%icc, 3f
 	membar		#StoreLoad | #StoreStore
+	bl,pn		%icc, 3f
+	 nop
 2:
 	retl
 	 nop
@@ -151,8 +155,9 @@ __downgrade_write:
 	bne,pn		%icc, 1b
 	 sub		%g7, %g1, %g7
 	cmp		%g7, 0
-	bl,pn		%icc, 3f
 	membar		#StoreLoad | #StoreStore
+	bl,pn		%icc, 3f
+	 nop
 2:
 	retl
 	 nop

arch/sparc64/mm/init.c

@@ -136,8 +136,9 @@ static __inline__ void set_dcache_dirty(struct page *page, int this_cpu)
 			     "or	%%g1, %0, %%g1\n\t"
 			     "casx	[%2], %%g7, %%g1\n\t"
 			     "cmp	%%g7, %%g1\n\t"
+			     "membar	#StoreLoad | #StoreStore\n\t"
 			     "bne,pn	%%xcc, 1b\n\t"
-			     " membar	#StoreLoad | #StoreStore"
+			     " nop"
 			     : /* no outputs */
 			     : "r" (mask), "r" (non_cpu_bits), "r" (&page->flags)
 			     : "g1", "g7");
@@ -157,8 +158,9 @@ static __inline__ void clear_dcache_dirty_cpu(struct page *page, unsigned long c
 			     " andn	%%g7, %1, %%g1\n\t"
 			     "casx	[%2], %%g7, %%g1\n\t"
 			     "cmp	%%g7, %%g1\n\t"
+			     "membar	#StoreLoad | #StoreStore\n\t"
 			     "bne,pn	%%xcc, 1b\n\t"
-			     " membar	#StoreLoad | #StoreStore\n"
+			     " nop\n"
 			     "2:"
 			     : /* no outputs */
 			     : "r" (cpu), "r" (mask), "r" (&page->flags),

arch/sparc64/mm/ultra.S

@@ -266,8 +266,9 @@ __cheetah_flush_tlb_pending:	/* 22 insns */
 	 andn		%o3, 1, %o3
 	stxa		%g0, [%o3] ASI_IMMU_DEMAP
 2:	stxa		%g0, [%o3] ASI_DMMU_DEMAP	
-	brnz,pt		%o1, 1b
 	membar		#Sync
+	brnz,pt		%o1, 1b
+	 nop
 	stxa		%g2, [%o4] ASI_DMMU
 	flush		%g6
 	wrpr		%g0, 0, %tl

include/asm-sparc64/rwsem.h

@@ -55,8 +55,9 @@ static __inline__ int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
 		"add		%%g1, %1, %%g7\n\t"
 		"cas		[%2], %%g1, %%g7\n\t"
 		"cmp		%%g1, %%g7\n\t"
+		"membar		#StoreLoad | #StoreStore\n\t"
 		"bne,pn		%%icc, 1b\n\t"
-		" membar	#StoreLoad | #StoreStore\n\t"
+		" nop\n\t"
 		"mov		%%g7, %0\n\t"
 		: "=&r" (tmp)
 		: "0" (tmp), "r" (sem)

include/asm-sparc64/spinlock.h

@@ -52,12 +52,14 @@ static inline void _raw_spin_lock(spinlock_t *lock)
 
 	__asm__ __volatile__(
 "1:	ldstub		[%1], %0\n"
-"	brnz,pn		%0, 2f\n"
 "	membar		#StoreLoad | #StoreStore\n"
+"	brnz,pn		%0, 2f\n"
+"	 nop\n"
 "	.subsection	2\n"
 "2:	ldub		[%1], %0\n"
-"	brnz,pt		%0, 2b\n"
 "	membar		#LoadLoad\n"
+"	brnz,pt		%0, 2b\n"
+"	 nop\n"
 "	ba,a,pt		%%xcc, 1b\n"
 "	.previous"
 	: "=&r" (tmp)
@@ -95,14 +97,16 @@ static inline void _raw_spin_lock_flags(spinlock_t *lock, unsigned long flags)
 
 	__asm__ __volatile__(
 "1:	ldstub		[%2], %0\n"
-"	brnz,pn		%0, 2f\n"
 "	membar		#StoreLoad | #StoreStore\n"
+"	brnz,pn		%0, 2f\n"
+"	 nop\n"
 "	.subsection	2\n"
 "2:	rdpr		%%pil, %1\n"
 "	wrpr		%3, %%pil\n"
 "3:	ldub		[%2], %0\n"
-"	brnz,pt		%0, 3b\n"
 "	membar		#LoadLoad\n"
+"	brnz,pt		%0, 3b\n"
+"	 nop\n"
 "	ba,pt		%%xcc, 1b\n"
 "	 wrpr		%1, %%pil\n"
 "	.previous"
@@ -162,12 +166,14 @@ static void inline __read_lock(rwlock_t *lock)
 "4:	 add		%0, 1, %1\n"
 "	cas		[%2], %0, %1\n"
 "	cmp		%0, %1\n"
-"	bne,pn		%%icc, 1b\n"
 "	membar		#StoreLoad | #StoreStore\n"
+"	bne,pn		%%icc, 1b\n"
+"	 nop\n"
 "	.subsection	2\n"
 "2:	ldsw		[%2], %0\n"
-"	brlz,pt		%0, 2b\n"
 "	membar		#LoadLoad\n"
+"	brlz,pt		%0, 2b\n"
+"	 nop\n"
 "	ba,a,pt		%%xcc, 4b\n"
 "	.previous"
 	: "=&r" (tmp1), "=&r" (tmp2)
@@ -204,12 +210,14 @@ static void inline __write_lock(rwlock_t *lock)
 "4:	 or		%0, %3, %1\n"
 "	cas		[%2], %0, %1\n"
 "	cmp		%0, %1\n"
-"	bne,pn		%%icc, 1b\n"
 "	membar		#StoreLoad | #StoreStore\n"
+"	bne,pn		%%icc, 1b\n"
+"	 nop\n"
 "	.subsection	2\n"
 "2:	lduw		[%2], %0\n"
-"	brnz,pt		%0, 2b\n"
 "	membar		#LoadLoad\n"
+"	brnz,pt		%0, 2b\n"
+"	 nop\n"
 "	ba,a,pt		%%xcc, 4b\n"
 "	.previous"
 	: "=&r" (tmp1), "=&r" (tmp2)
@@ -240,8 +248,9 @@ static int inline __write_trylock(rwlock_t *lock)
 "	 or		%0, %4, %1\n"
 "	cas		[%3], %0, %1\n"
 "	cmp		%0, %1\n"
-"	bne,pn		%%icc, 1b\n"
 "	membar		#StoreLoad | #StoreStore\n"
+"	bne,pn		%%icc, 1b\n"
+"	 nop\n"
 "	mov		1, %2\n"
 "2:"
 	: "=&r" (tmp1), "=&r" (tmp2), "=&r" (result)

include/asm-sparc64/spitfire.h

@@ -111,7 +111,6 @@ static __inline__ void spitfire_put_dcache_tag(unsigned long addr, unsigned long
 			     "membar	#Sync"
 			     : /* No outputs */
 			     : "r" (tag), "r" (addr), "i" (ASI_DCACHE_TAG));
-	__asm__ __volatile__ ("membar #Sync" : : : "memory");
 }
 
 /* The instruction cache lines are flushed with this, but note that