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| author | Ingo Molnar <mingo@kernel.org> | 2015-04-27 07:59:11 (GMT) |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-05-19 13:47:54 (GMT) |
| commit | 68271c6ae726d7ab51e39b7342c838761bf0a25c (patch) | |
| tree | 0184bb65cd74a7d9e2dddc5dbd43b0d0f6d478e3 /arch/x86/kernel/fpu | |
| parent | 48c4717f30cc1f83d02f045c3b47a2885863bff2 (diff) | |
| download | linux-68271c6ae726d7ab51e39b7342c838761bf0a25c.tar.xz | |
x86/fpu: Optimize fpu_copy()
Optimize fpu_copy() a bit by expanding the ->fpstate_active == 1
portion of fpu__save() into it.
( The main purpose of this change is to enable another, larger
optimization that will be done in the next patch. )
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/fpu')
| -rw-r--r-- | arch/x86/kernel/fpu/core.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index b1fbbb8..41ea25a 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -224,7 +224,10 @@ static void fpu_copy(struct fpu *dst_fpu, struct fpu *src_fpu) memset(&dst_fpu->state.xsave, 0, xstate_size); copy_fpregs_to_fpstate(dst_fpu); } else { - fpu__save(src_fpu); + preempt_disable(); + if (!copy_fpregs_to_fpstate(src_fpu)) + fpregs_deactivate(src_fpu); + preempt_enable(); memcpy(&dst_fpu->state, &src_fpu->state, xstate_size); } } |