[POWERPC] Remove barriers from the SLB shadow buffer update

[linux-2.6-omap-h63xx.git] / arch / powerpc / kernel / entry_64.S

diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 952eba6701f404c2d8ec1a69b2a6595d26250f94..fbbd3f6f006453dc217dfa8e818a1860156edbc1 100644 (file)
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -385,15 +385,15 @@ BEGIN_FTR_SECTION
        oris    r0,r6,(SLB_ESID_V)@h
        ori     r0,r0,(SLB_NUM_BOLTED-1)@l
 
-       /* Update the last bolted SLB */
+       /* Update the last bolted SLB.  No write barriers are needed
+        * here, provided we only update the current CPU's SLB shadow
+        * buffer.
+        */
        ld      r9,PACA_SLBSHADOWPTR(r13)
        li      r12,0
        std     r12,SLBSHADOW_STACKESID(r9) /* Clear ESID */
-       eieio
        std     r7,SLBSHADOW_STACKVSID(r9)  /* Save VSID */
-       eieio
        std     r0,SLBSHADOW_STACKESID(r9)  /* Save ESID */
-       eieio
 
        slbie   r6
        slbie   r6              /* Workaround POWER5 < DD2.1 issue */