[tip:x86/fpu] x86, fpu: Merge tolerant_fwait()
From: tip-bot for Brian Gerst
Date: Thu Sep 09 2010 - 21:48:15 EST
Commit-ID: 51115d4d45700fc7c08306f7ba6e68551f526ae5
Gitweb: http://git.kernel.org/tip/51115d4d45700fc7c08306f7ba6e68551f526ae5
Author: Brian Gerst <brgerst@xxxxxxxxx>
AuthorDate: Fri, 3 Sep 2010 21:17:10 -0400
Committer: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
CommitDate: Thu, 9 Sep 2010 14:16:25 -0700
x86, fpu: Merge tolerant_fwait()
Commit e2e75c91 merged the math exception handler, allowing both 32-bit
and 64-bit to handle math exceptions from kernel mode. Switch to using
the 64-bit version of tolerant_fwait() without fnclex, which simply
ignores the exception if one is still pending from userspace.
Signed-off-by: Brian Gerst <brgerst@xxxxxxxxx>
Acked-by: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
LKML-Reference: <1283563039-3466-4-git-send-email-brgerst@xxxxxxxxx>
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/i387.h | 19 ++++---------------
1 files changed, 4 insertions(+), 15 deletions(-)
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index a73a8d5..5d8f9a7 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -77,15 +77,6 @@ static inline void sanitize_i387_state(struct task_struct *tsk)
}
#ifdef CONFIG_X86_64
-
-/* Ignore delayed exceptions from user space */
-static inline void tolerant_fwait(void)
-{
- asm volatile("1: fwait\n"
- "2:\n"
- _ASM_EXTABLE(1b, 2b));
-}
-
static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
{
int err;
@@ -220,11 +211,6 @@ extern void finit_soft_fpu(struct i387_soft_struct *soft);
static inline void finit_soft_fpu(struct i387_soft_struct *soft) {}
#endif
-static inline void tolerant_fwait(void)
-{
- asm volatile("fnclex ; fwait");
-}
-
/* perform fxrstor iff the processor has extended states, otherwise frstor */
static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
{
@@ -344,7 +330,10 @@ static inline void __unlazy_fpu(struct task_struct *tsk)
static inline void __clear_fpu(struct task_struct *tsk)
{
if (task_thread_info(tsk)->status & TS_USEDFPU) {
- tolerant_fwait();
+ /* Ignore delayed exceptions from user space */
+ asm volatile("1: fwait\n"
+ "2:\n"
+ _ASM_EXTABLE(1b, 2b));
task_thread_info(tsk)->status &= ~TS_USEDFPU;
stts();
}
--
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