From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965942AbbEER6W (ORCPT ); Tue, 5 May 2015 13:58:22 -0400 Received: from mail-wi0-f175.google.com ([209.85.212.175]:38217 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031546AbbEERyA (ORCPT ); Tue, 5 May 2015 13:54:00 -0400 From: Ingo Molnar To: linux-kernel@vger.kernel.org Cc: Andy Lutomirski , Borislav Petkov , Dave Hansen , Fenghua Yu , "H. Peter Anvin" , Linus Torvalds , Oleg Nesterov , Thomas Gleixner Subject: [PATCH 147/208] x86/fpu: Optimize fpu_copy() Date: Tue, 5 May 2015 19:50:39 +0200 Message-Id: <1430848300-27877-69-git-send-email-mingo@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1430848300-27877-1-git-send-email-mingo@kernel.org> References: <1430848300-27877-1-git-send-email-mingo@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/kernel/fpu/core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 8835b802aa16..7fdeabc1f2af 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); } } -- 2.1.0