x86, xsave: Use xsaveopt in context-switch path when supported
authorSuresh Siddha <suresh.b.siddha@intel.com>
Mon, 19 Jul 2010 23:05:52 +0000 (16:05 -0700)
committerH. Peter Anvin <hpa@linux.intel.com>
Tue, 20 Jul 2010 00:52:24 +0000 (17:52 -0700)
commit6bad06b768920e278c7cedfdda56a0b4c6a35ee9
treed84dd7d1f0f9afcf4880cea734bf3a32e8e9804c
parent29104e101d710dd152f807978884643a52eca8b7
x86, xsave: Use xsaveopt in context-switch path when supported

xsaveopt is a more optimized form of xsave specifically designed
for the context switch usage. xsaveopt doesn't save the state that's not
modified from the prior xrstor. And if a specific feature state gets
modified to the init state, then xsaveopt just updates the header bit
in the xsave memory layout without updating the corresponding memory
layout.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <20100719230205.604014179@sbs-t61.sc.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/include/asm/i387.h
arch/x86/include/asm/xsave.h
arch/x86/kernel/cpu/common.c