[PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP.

Joakim Tjernlund Joakim.Tjernlund at transmode.se
Wed Mar 3 02:37:11 EST 2010


Only the swap function cares about the ACCESSED bit in
the pte. Do not waste cycles updateting ACCESSED when swap
is not compiled into the kernel.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund at transmode.se>
---
 arch/powerpc/kernel/head_8xx.S |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 84ca1d9..6478a96 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -343,10 +343,11 @@ InstructionTLBMiss:
 	mfspr	r11, SPRN_MD_TWC	/* ....and get the pte address */
 	lwz	r10, 0(r11)	/* Get the pte */
 
+#ifdef CONFIG_SWAP
 	andi.	r11, r10, _PAGE_ACCESSED | _PAGE_PRESENT
 	cmpwi	cr0, r11, _PAGE_ACCESSED | _PAGE_PRESENT
 	bne-	cr0, 2f
-
+#endif
 	/* The Linux PTE won't go exactly into the MMU TLB.
 	 * Software indicator bits 21 and 28 must be clear.
 	 * Software indicator bits 24, 25, 26, and 27 must be
@@ -439,10 +440,11 @@ DataStoreTLBMiss:
 	 * r11 = ((r10 & PRESENT) & ((r10 & ACCESSED) >> 5));
 	 * r10 = (r10 & ~PRESENT) | r11;
 	 */
+#ifdef CONFIG_SWAP
 	rlwinm	r11, r10, 32-5, _PAGE_PRESENT
 	and	r11, r11, r10
 	rlwimi	r10, r11, 0, _PAGE_PRESENT
-
+#endif
 	/* Honour kernel RO, User NA */
 	/* 0x200 == Extended encoding, bit 22 */
 	rlwimi	r10, r10, 32-2, 0x200 /* Copy USER to bit 22, 0x200 */
-- 
1.6.4.4



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