[PATCH 3/4] 8xx: Don't touch ACCESSED when no SWAP.
From: Joakim Tjernlund <hidden>
Date: 2010-02-26 08:39:17
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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. --- 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