From 6bad06b768920e278c7cedfdda56a0b4c6a35ee9 Mon Sep 17 00:00:00 2001 From: Suresh Siddha Date: Mon, 19 Jul 2010 16:05:52 -0700 Subject: 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 LKML-Reference: <20100719230205.604014179@sbs-t61.sc.intel.com> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/common.c | 8 ++++++++ 1 file changed, 8 insertions(+) (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 c7358303d8cd..3f715efc594d 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -140,10 +140,18 @@ EXPORT_PER_CPU_SYMBOL_GPL(gdt_page); static int __init x86_xsave_setup(char *s) { setup_clear_cpu_cap(X86_FEATURE_XSAVE); + setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); return 1; } __setup("noxsave", x86_xsave_setup); +static int __init x86_xsaveopt_setup(char *s) +{ + setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT); + return 1; +} +__setup("noxsaveopt", x86_xsaveopt_setup); + #ifdef CONFIG_X86_32 static int cachesize_override __cpuinitdata = -1; static int disable_x86_serial_nr __cpuinitdata = 1; -- cgit v1.2.3