linux-kernel - [PATCH 06/10] x86, xsave: do not initialize xsave in fpu

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Date:	Tue, 20 Jul 2010 20:50:53 +0200
From:	Robert Richter <robert.richter@....com>
To:	"H. Peter Anvin" <hpa@...or.com>
CC:	Ingo Molnar <mingo@...e.hu>,
	Suresh Siddha <suresh.b.siddha@...el.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Robert Richter <robert.richter@....com>
Subject: [PATCH 06/10] x86, xsave: do not initialize xsave in fpu_init()

As xsave also supports other than fpu features, it should be
initialized independently of the fpu. This patch moves this out of fpu
initialization.

Signed-off-by: Robert Richter <robert.richter@....com>
---
 arch/x86/include/asm/i387.h  |    1 -
 arch/x86/kernel/cpu/common.c |    2 ++
 arch/x86/kernel/i387.c       |   17 ++++++++++++++---
 arch/x86/kernel/xsave.c      |    4 +---
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 59bd93a..509ddab 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -31,7 +31,6 @@ extern void mxcsr_feature_mask_init(void);
 extern int init_fpu(struct task_struct *child);
 extern asmlinkage void math_state_restore(void);
 extern void __math_state_restore(void);
-extern void init_thread_xstate(void);
 extern int dump_fpu(struct pt_regs *, struct user_i387_struct *);
 
 extern user_regset_active_fn fpregs_active, xfpregs_active;
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 1a053e0..d8eba22 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1209,6 +1209,7 @@ void __cpuinit cpu_init(void)
 	clear_all_debug_regs();
 	dbg_restore_debug_regs();
 
+	xsave_init();
 	fpu_init();
 
 	raw_local_save_flags(kernel_eflags);
@@ -1271,5 +1272,6 @@ void __cpuinit cpu_init(void)
 	mxcsr_feature_mask_init();
 
 	xsave_init();
+	fpu_init();
 }
 #endif
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index 196b8c7..122a764 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -59,7 +59,7 @@ void __cpuinit mxcsr_feature_mask_init(void)
 	stts();
 }
 
-void __cpuinit init_thread_xstate(void)
+static void __cpuinit init_thread_xstate(void)
 {
 	if (!HAVE_HWFP) {
 		xstate_size = sizeof(struct i387_soft_struct);
@@ -83,6 +83,7 @@ void __cpuinit init_thread_xstate(void)
  * Called at bootup to set up the initial FPU state that is later cloned
  * into all processes.
  */
+
 void __cpuinit fpu_init(void)
 {
 	unsigned long oldcr0 = read_cr0();
@@ -92,14 +93,24 @@ void __cpuinit fpu_init(void)
 
 	write_cr0(oldcr0 & ~(X86_CR0_TS|X86_CR0_EM)); /* clear TS and EM */
 
-	xsave_init();
+	if (!smp_processor_id())
+		init_thread_xstate();
 
 	mxcsr_feature_mask_init();
 	/* clean state in init */
 	current_thread_info()->status = 0;
 	clear_used_math();
 }
-#endif	/* CONFIG_X86_64 */
+
+#else	/* CONFIG_X86_64 */
+
+void __cpuinit fpu_init(void)
+{
+	if (!smp_processor_id())
+		init_thread_xstate();
+}
+
+#endif	/* CONFIG_X86_32 */
 
 static void fpu_finit(struct fpu *fpu)
 {
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index c46082d..a594f49 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -472,9 +472,7 @@ void __cpuinit xsave_init(void)
 	/*
 	 * Boot processor to setup the FP and extended state context info.
 	 */
-	if (!smp_processor_id()) {
+	if (!smp_processor_id())
 		xsave_cntxt_init();
-		init_thread_xstate();
-	}
 	__xsave_init();
 }
-- 
1.7.1.1


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