From 349c004e3d31fda23ad225b61861be38047fff16 Mon Sep 17 00:00:00 2001 From: Christoph Lameter Date: Sat, 12 Mar 2011 12:50:10 +0100 Subject: x86: A fast way to check capabilities of the current cpu Add this_cpu_has() which determines if the current cpu has a certain ability using a segment prefix and a bit test operation. For that we need to add bit operations to x86s percpu.h. Many uses of cpu_has use a pointer passed to a function to determine the current flags. That is no longer necessary after this patch. However, this patch only converts the straightforward cases where cpu_has is used with this_cpu_ptr. The rest is work for later. -tj: Rolled up patch to add x86_ prefix and use percpu_read() instead of percpu_read_stable(). Signed-off-by: Christoph Lameter Acked-by: Tejun Heo Signed-off-by: Tejun Heo --- arch/x86/kernel/apic/apic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/kernel/apic') diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index fabf01eff771..2bc503bf9e99 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -505,7 +505,7 @@ static void __cpuinit setup_APIC_timer(void) { struct clock_event_device *levt = &__get_cpu_var(lapic_events); - if (cpu_has(__this_cpu_ptr(&cpu_info), X86_FEATURE_ARAT)) { + if (this_cpu_has(X86_FEATURE_ARAT)) { lapic_clockevent.features &= ~CLOCK_EVT_FEAT_C3STOP; /* Make LAPIC timer preferrable over percpu HPET */ lapic_clockevent.rating = 150; -- cgit