[PATCH v2 2/4] powerpc/mm: Remove unused register usage in SW TLB miss handling
From: Kumar Gala <hidden>
Date: 2009-03-16 21:21:23
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Long ago we had some code that actually used the CTR in the SW TLB miss handlers (603/e300). Since we don't use it no reason to waste cycles saving it off and restoring it (we actually didn't restore it in the fast path case). Signed-off-by: Kumar Gala <redacted> --- arch/powerpc/kernel/head_32.S | 11 +++-------- 1 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index d0bad4b..f37df0c 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S@@ -475,12 +475,11 @@ SystemCall: . = 0x1000 InstructionTLBMiss: /* - * r0: stored ctr + * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ - mfctr r0 /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_IMISS lis r1,PAGE_OFFSET@h /* check if kernel address */
@@ -531,7 +530,6 @@ InstructionAddressInvalid: addis r1,r1,0x2000 mtspr SPRN_DSISR,r1 /* (shouldn't be needed) */ - mtctr r0 /* Restore CTR */ andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */ or r2,r2,r1 mtspr SPRN_SRR1,r2
@@ -552,12 +550,11 @@ InstructionAddressInvalid: . = 0x1100 DataLoadTLBMiss: /* - * r0: stored ctr + * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ - mfctr r0 /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_DMISS lis r1,PAGE_OFFSET@h /* check if kernel address */
@@ -607,7 +604,6 @@ DataAddressInvalid: rlwinm r1,r3,9,6,6 /* Get load/store bit */ addis r1,r1,0x2000 mtspr SPRN_DSISR,r1 - mtctr r0 /* Restore CTR */ andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */ mtspr SPRN_SRR1,r2 mfspr r1,SPRN_DMISS /* Get failing address */
@@ -627,12 +623,11 @@ DataAddressInvalid: . = 0x1200 DataStoreTLBMiss: /* - * r0: stored ctr + * r0: scratch * r1: linux style pte ( later becomes ppc hardware pte ) * r2: ptr to linux-style pte * r3: scratch */ - mfctr r0 /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_DMISS lis r1,PAGE_OFFSET@h /* check if kernel address */
--
1.5.6.6