powerpc/8xx: Don't touch ACCESSED when no SWAP.

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@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 84ca1d9..6478a96 100644 (file)
--- 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 */