Now that r0 is free we can keep the value of I/DMISS in r3 and not reload
it before doing the tlbli/d. This saves us a few cycles in the fast path
case.
Signed-off-by: Kumar Gala <ga...@kernel.crashing.org>
---
arch/powerpc/kernel/head_32.S | 51 +++++++++++++++++++---------------------
1 files changed, 24 insertions(+), 27 deletions(-)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index 0105fd5..8a9dc79 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -495,28 +495,27 @@ InstructionTLBMiss:
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- InstructionAddressInvalid /* return if no mapping */
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
- lwz r3,0(r2) /* get linux-style pte */
- andc. r1,r1,r3 /* check access & ~permission */
+ lwz r0,0(r2) /* get linux-style pte */
+ andc. r1,r1,r0 /* check access & ~permission */
bne- InstructionAddressInvalid /* return if access not permitted */
- ori r3,r3,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
+ ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
- stw r3,0(r2) /* update PTE (accessed bit) */
+ stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */
- rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
+ rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
+ rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
and r1,r1,r2 /* writable if _RW and _DIRTY */
- rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
- rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */
+ rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
+ rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
ori r1,r1,0xe04 /* clear out reserved bits */
- andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
+ andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
BEGIN_FTR_SECTION
rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
mtspr SPRN_RPA,r1
- mfspr r3,SPRN_IMISS
tlbli r3
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
mtcrf 0x80,r3
@@ -570,28 +569,27 @@ DataLoadTLBMiss:
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- DataAddressInvalid /* return if no mapping */
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
- lwz r3,0(r2) /* get linux-style pte */
- andc. r1,r1,r3 /* check access & ~permission */
+ lwz r0,0(r2) /* get linux-style pte */
+ andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
- ori r3,r3,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
+ ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
- stw r3,0(r2) /* update PTE (accessed bit) */
+ stw r0,0(r2) /* update PTE (accessed bit) */
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwinm r1,r3,32-10,31,31 /* _PAGE_RW -> PP lsb */
- rlwinm r2,r3,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
+ rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
+ rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
and r1,r1,r2 /* writable if _RW and _DIRTY */
- rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
- rlwimi r3,r3,32-1,31,31 /* _PAGE_USER -> PP lsb */
+ rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
+ rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
ori r1,r1,0xe04 /* clear out reserved bits */
- andc r1,r3,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
+ andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
BEGIN_FTR_SECTION
rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
mtspr SPRN_RPA,r1
- mfspr r3,SPRN_DMISS
tlbld r3
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
mtcrf 0x80,r3
@@ -643,24 +641,23 @@ DataStoreTLBMiss:
rlwinm. r2,r2,0,0,19 /* extract address of pte page */
beq- DataAddressInvalid /* return if no mapping */
rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
- lwz r3,0(r2) /* get linux-style pte */
- andc. r1,r1,r3 /* check access & ~permission */
+ lwz r0,0(r2) /* get linux-style pte */
+ andc. r1,r1,r0 /* check access & ~permission */
bne- DataAddressInvalid /* return if access not permitted */
- ori r3,r3,_PAGE_ACCESSED|_PAGE_DIRTY
+ ori r0,r0,_PAGE_ACCESSED|_PAGE_DIRTY
/*
* NOTE! We are assuming this is not an SMP system, otherwise
* we would need to update the pte atomically with lwarx/stwcx.
*/
- stw r3,0(r2) /* update PTE (accessed/dirty bits) */
+ stw r0,0(r2) /* update PTE (accessed/dirty bits) */
/* Convert linux-style PTE to low word of PPC-style PTE */
- rlwimi r3,r3,32-1,30,30 /* _PAGE_USER -> PP msb */
+ rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
li r1,0xe05 /* clear out reserved bits & PP lsb */
- andc r1,r3,r1 /* PP = user? 2: 0 */
+ andc r1,r0,r1 /* PP = user? 2: 0 */
BEGIN_FTR_SECTION
rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
mtspr SPRN_RPA,r1
- mfspr r3,SPRN_DMISS
tlbld r3
mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
mtcrf 0x80,r3
--
1.5.6.6
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