From c9ad488289144ae5ef53b012e15895ef1f5e4bb6 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Thu, 6 May 2010 11:45:45 +0300 Subject: x86: Eliminate TS_XSAVE The fpu code currently uses current->thread_info->status & TS_XSAVE as a way to distinguish between XSAVE capable processors and older processors. The decision is not really task specific; instead we use the task status to avoid a global memory reference - the value should be the same across all threads. Eliminate this tie-in into the task structure by using an alternative instruction keyed off the XSAVE cpu feature; this results in shorter and faster code, without introducing a global memory reference. [ hpa: in the future, this probably should use an asm jmp ] Signed-off-by: Avi Kivity Acked-by: Suresh Siddha LKML-Reference: <1273135546-29690-2-git-send-email-avi@redhat.com> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/common.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'arch/x86/kernel/cpu/common.c') diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 4868e4a951ee..c1c00d0b1692 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1243,10 +1243,7 @@ void __cpuinit cpu_init(void) /* * Force FPU initialization: */ - if (cpu_has_xsave) - current_thread_info()->status = TS_XSAVE; - else - current_thread_info()->status = 0; + current_thread_info()->status = 0; clear_used_math(); mxcsr_feature_mask_init(); -- cgit v1.2.2