From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933662AbaE3PMT (ORCPT ); Fri, 30 May 2014 11:12:19 -0400 Received: from terminus.zytor.com ([198.137.202.10]:44139 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933638AbaE3PMP (ORCPT ); Fri, 30 May 2014 11:12:15 -0400 Date: Fri, 30 May 2014 08:12:03 -0700 From: tip-bot for Fenghua Yu Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, fenghua.yu@intel.com, tglx@linutronix.de, hpa@linux.intel.com Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, fenghua.yu@intel.com, tglx@linutronix.de, hpa@linux.intel.com In-Reply-To: <1401387164-43416-9-git-send-email-fenghua.yu@intel.com> References: <1401387164-43416-9-git-send-email-fenghua.yu@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/xsave] x86/xsaves: Use xsaves/ xrstors to save and restore xsave area Git-Commit-ID: f31a9f7c71691569359fa7fb8b0acaa44bce0324 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: f31a9f7c71691569359fa7fb8b0acaa44bce0324 Gitweb: http://git.kernel.org/tip/f31a9f7c71691569359fa7fb8b0acaa44bce0324 Author: Fenghua Yu AuthorDate: Thu, 29 May 2014 11:12:36 -0700 Committer: H. Peter Anvin CommitDate: Thu, 29 May 2014 14:31:21 -0700 x86/xsaves: Use xsaves/xrstors to save and restore xsave area If xsaves is eanbled, use xsaves/xrstors instrucitons to save and restore xstate. xsaves and xrstors support compacted format, init optimization, modified optimization, and supervisor states. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1401387164-43416-9-git-send-email-fenghua.yu@intel.com Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/xsave.h | 84 +++++++++++++++++++++++++++++++++----------- 1 file changed, 64 insertions(+), 20 deletions(-) diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 76c2459..f9177a2 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -65,6 +65,70 @@ extern int init_fpu(struct task_struct *child); _ASM_EXTABLE(1b, 3b) \ : [err] "=r" (err) +/* + * Save processor xstate to xsave area. + */ +static inline int xsave_state(struct xsave_struct *fx, u64 mask) +{ + u32 lmask = mask; + u32 hmask = mask >> 32; + int err = 0; + + /* + * If xsaves is enabled, xsaves replaces xsaveopt because + * it supports compact format and supervisor states in addition to + * modified optimization in xsaveopt. + * + * Otherwise, if xsaveopt is enabled, xsaveopt replaces xsave + * because xsaveopt supports modified optimization which is not + * supported by xsave. + * + * If none of xsaves and xsaveopt is enabled, use xsave. + */ + alternative_input_2( + "1:"XSAVE, + "1:"XSAVEOPT, + X86_FEATURE_XSAVEOPT, + "1:"XSAVES, + X86_FEATURE_XSAVES, + [fx] "D" (fx), "a" (lmask), "d" (hmask) : + "memory"); + asm volatile("2:\n\t" + xstate_fault + : "0" (0) + : "memory"); + + return err; +} + +/* + * Restore processor xstate from xsave area. + */ +static inline int xrstor_state(struct xsave_struct *fx, u64 mask) +{ + int err = 0; + u32 lmask = mask; + u32 hmask = mask >> 32; + + /* + * Use xrstors to restore context if it is enabled. xrstors supports + * compacted format of xsave area which is not supported by xrstor. + */ + alternative_input( + "1: " XRSTOR, + "1: " XRSTORS, + X86_FEATURE_XSAVES, + "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) + : "memory"); + + asm volatile("2:\n" + xstate_fault + : "0" (0) + : "memory"); + + return err; +} + static inline int fpu_xrstor_checking(struct xsave_struct *fx) { int err; @@ -130,26 +194,6 @@ static inline int xrestore_user(struct xsave_struct __user *buf, u64 mask) return err; } -static inline void xrstor_state(struct xsave_struct *fx, u64 mask) -{ - u32 lmask = mask; - u32 hmask = mask >> 32; - - asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x2f\n\t" - : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) - : "memory"); -} - -static inline void xsave_state(struct xsave_struct *fx, u64 mask) -{ - u32 lmask = mask; - u32 hmask = mask >> 32; - - asm volatile(".byte " REX_PREFIX "0x0f,0xae,0x27\n\t" - : : "D" (fx), "m" (*fx), "a" (lmask), "d" (hmask) - : "memory"); -} - static inline void fpu_xsave(struct fpu *fpu) { /* This, however, we can work around by forcing the compiler to select