linux-kernel - [PATCH 032/208] x86/fpu: Simplify the xsave

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Date:	Tue,  5 May 2015 18:24:12 +0200
From:	Ingo Molnar <mingo@...nel.org>
To:	linux-kernel@...r.kernel.org
Cc:	Andy Lutomirski <luto@...capital.net>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	Fenghua Yu <fenghua.yu@...el.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Oleg Nesterov <oleg@...hat.com>,
	Thomas Gleixner <tglx@...utronix.de>
Subject: [PATCH 032/208] x86/fpu: Simplify the xsave_state*() methods

These functions (xsave_state() and xsave_state_booting()) have a 'mask'
argument that is always -1.

Propagate this into the functions instead and eliminate the extra argument.

Does not change the generated code, because these were inlined functions.

Reviewed-by: Borislav Petkov <bp@...en8.de>
Cc: Andy Lutomirski <luto@...capital.net>
Cc: Dave Hansen <dave.hansen@...ux.intel.com>
Cc: Fenghua Yu <fenghua.yu@...el.com>
Cc: H. Peter Anvin <hpa@...or.com>
Cc: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Oleg Nesterov <oleg@...hat.com>
Cc: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
---
 arch/x86/include/asm/fpu-internal.h | 4 ++--
 arch/x86/include/asm/xsave.h        | 8 +++++---
 arch/x86/kernel/fpu/xsave.c         | 3 ++-
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index c3b7bd12f18f..b1f5dd63cfeb 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -527,9 +527,9 @@ static inline void __save_fpu(struct task_struct *tsk)
 {
 	if (use_xsave()) {
 		if (unlikely(system_state == SYSTEM_BOOTING))
-			xsave_state_booting(&tsk->thread.fpu.state->xsave, -1);
+			xsave_state_booting(&tsk->thread.fpu.state->xsave);
 		else
-			xsave_state(&tsk->thread.fpu.state->xsave, -1);
+			xsave_state(&tsk->thread.fpu.state->xsave);
 	} else
 		fpu_fxsave(&tsk->thread.fpu);
 }
diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h
index 58ed0ca5a11e..61c951ce77fe 100644
--- a/arch/x86/include/asm/xsave.h
+++ b/arch/x86/include/asm/xsave.h
@@ -70,8 +70,9 @@ extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask);
  * This function is called only during boot time when x86 caps are not set
  * up and alternative can not be used yet.
  */
-static inline int xsave_state_booting(struct xsave_struct *fx, u64 mask)
+static inline int xsave_state_booting(struct xsave_struct *fx)
 {
+	u64 mask = -1;
 	u32 lmask = mask;
 	u32 hmask = mask >> 32;
 	int err = 0;
@@ -123,8 +124,9 @@ static inline int xrstor_state_booting(struct xsave_struct *fx, u64 mask)
 /*
  * Save processor xstate to xsave area.
  */
-static inline int xsave_state(struct xsave_struct *fx, u64 mask)
+static inline int xsave_state(struct xsave_struct *fx)
 {
+	u64 mask = -1;
 	u32 lmask = mask;
 	u32 hmask = mask >> 32;
 	int err = 0;
@@ -189,7 +191,7 @@ static inline int xrstor_state(struct xsave_struct *fx, u64 mask)
  */
 static inline void fpu_xsave(struct fpu *fpu)
 {
-	xsave_state(&fpu->state->xsave, -1);
+	xsave_state(&fpu->state->xsave);
 }
 
 /*
diff --git a/arch/x86/kernel/fpu/xsave.c b/arch/x86/kernel/fpu/xsave.c
index d913d5024901..a52205b87acb 100644
--- a/arch/x86/kernel/fpu/xsave.c
+++ b/arch/x86/kernel/fpu/xsave.c
@@ -558,11 +558,12 @@ static void __init setup_init_fpu_buf(void)
 	 * Init all the features state with header_bv being 0x0
 	 */
 	xrstor_state_booting(init_xstate_buf, -1);
+
 	/*
 	 * Dump the init state again. This is to identify the init state
 	 * of any feature which is not represented by all zero's.
 	 */
-	xsave_state_booting(init_xstate_buf, -1);
+	xsave_state_booting(init_xstate_buf);
 }
 
 static enum { AUTO, ENABLE, DISABLE } eagerfpu = AUTO;
-- 
2.1.0

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