From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762246AbbEERxs (ORCPT ); Tue, 5 May 2015 13:53:48 -0400 Received: from mail-wg0-f46.google.com ([74.125.82.46]:35731 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759534AbbEERxd (ORCPT ); Tue, 5 May 2015 13:53:33 -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 131/208] x86/fpu: Uninline the irq_ts_save()/restore() functions Date: Tue, 5 May 2015 19:50:23 +0200 Message-Id: <1430848300-27877-53-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 Especially the irq_ts_save() function is pretty bloaty, generating over a dozen instructions, so uninline them. Even though the API is used rarely, the space savings are measurable: text data bss dec hex filename 13331995 2572920 1634304 17539219 10ba093 vmlinux.before 13331739 2572920 1634304 17538963 10b9f93 vmlinux.after ( This also allows the removal of an include file inclusion from fpu/api.h, speeding up the kernel build slightly. ) 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/include/asm/fpu/api.h | 27 ++------------------------- arch/x86/kernel/fpu/core.c | 30 ++++++++++++++++++++++++++++++ 2 files changed, 32 insertions(+), 25 deletions(-) diff --git a/arch/x86/include/asm/fpu/api.h b/arch/x86/include/asm/fpu/api.h index 0c713455fc63..62035cc1d961 100644 --- a/arch/x86/include/asm/fpu/api.h +++ b/arch/x86/include/asm/fpu/api.h @@ -10,8 +10,6 @@ #ifndef _ASM_X86_FPU_API_H #define _ASM_X86_FPU_API_H -#include - /* * Careful: __kernel_fpu_begin/end() must be called with preempt disabled * and they don't touch the preempt state on their own. @@ -35,28 +33,7 @@ extern bool irq_fpu_usable(void); * in interrupt context interacting wrongly with other user/kernel fpu usage, we * should use them only in the context of irq_ts_save/restore() */ -static inline int irq_ts_save(void) -{ - /* - * If in process context and not atomic, we can take a spurious DNA fault. - * Otherwise, doing clts() in process context requires disabling preemption - * or some heavy lifting like kernel_fpu_begin() - */ - if (!in_atomic()) - return 0; - - if (read_cr0() & X86_CR0_TS) { - clts(); - return 1; - } - - return 0; -} - -static inline void irq_ts_restore(int TS_state) -{ - if (TS_state) - stts(); -} +extern int irq_ts_save(void); +extern void irq_ts_restore(int TS_state); #endif /* _ASM_X86_FPU_API_H */ diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 15fd714b6a83..34a4e1032424 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -6,6 +6,7 @@ * Gareth Hughes , May 2000 */ #include +#include /* * Track whether the kernel is using the FPU state @@ -140,6 +141,35 @@ void kernel_fpu_end(void) } EXPORT_SYMBOL_GPL(kernel_fpu_end); +/* + * CR0::TS save/restore functions: + */ +int irq_ts_save(void) +{ + /* + * If in process context and not atomic, we can take a spurious DNA fault. + * Otherwise, doing clts() in process context requires disabling preemption + * or some heavy lifting like kernel_fpu_begin() + */ + if (!in_atomic()) + return 0; + + if (read_cr0() & X86_CR0_TS) { + clts(); + return 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(irq_ts_save); + +void irq_ts_restore(int TS_state) +{ + if (TS_state) + stts(); +} +EXPORT_SYMBOL_GPL(irq_ts_restore); + static void __save_fpu(struct fpu *fpu) { if (use_xsave()) { -- 2.1.0