[PATCH] Use string instructions for Core2 copy/clear

It is faster than using a unrolled loop for the use cases the kernel
cares about (cached, sizes typically < 4K)

Signed-off-by: Andi Kleen <ak@suse.de>

diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c
index e328e3eb8cbeb86a8f095b220484e1924d35d2b3..085f2e09b9dc5222a61e70a8a84db69940b51c5f 100644 (file)
--- a/arch/x86_64/kernel/setup.c
+++ b/arch/x86_64/kernel/setup.c
@@ -843,6 +843,8 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
        if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
            (c->x86 == 0x6 && c->x86_model >= 0x0e))
                set_bit(X86_FEATURE_CONSTANT_TSC, &c->x86_capability);
+       if (c->x86 == 6)
+               set_bit(X86_FEATURE_REP_GOOD, &c->x86_capability);
        set_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability);
        c->x86_max_cores = intel_num_cpu_cores(c);