[tip:x86/fpu] x86, fpu: Merge fpu_save_init()

From: tip-bot for Brian Gerst
Date: Thu Sep 09 2010 - 21:54:59 EST


Commit-ID: b2b57fe053c9cf8b8af5a0e826a465996afed0ff
Gitweb: http://git.kernel.org/tip/b2b57fe053c9cf8b8af5a0e826a465996afed0ff
Author: Brian Gerst <brgerst@xxxxxxxxx>
AuthorDate: Fri, 3 Sep 2010 21:17:19 -0400
Committer: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
CommitDate: Thu, 9 Sep 2010 14:17:36 -0700

x86, fpu: Merge fpu_save_init()

Make 64-bit use the 32-bit version of fpu_save_init(). Remove
unused clear_fpu_state().

Signed-off-by: Brian Gerst <brgerst@xxxxxxxxx>
Acked-by: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
LKML-Reference: <1283563039-3466-13-git-send-email-brgerst@xxxxxxxxx>
Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/i387.h | 48 +++---------------------------------------
1 files changed, 4 insertions(+), 44 deletions(-)

diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index b45abef..70626ed 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -105,36 +105,6 @@ static inline int fxrstor_checking(struct i387_fxsave_struct *fx)
return err;
}

-/* AMD CPUs don't save/restore FDP/FIP/FOP unless an exception
- is pending. Clear the x87 state here by setting it to fixed
- values. The kernel data segment can be sometimes 0 and sometimes
- new user value. Both should be ok.
- Use the PDA as safe address because it should be already in L1. */
-static inline void fpu_clear(struct fpu *fpu)
-{
- struct xsave_struct *xstate = &fpu->state->xsave;
- struct i387_fxsave_struct *fx = &fpu->state->fxsave;
-
- /*
- * xsave header may indicate the init state of the FP.
- */
- if (use_xsave() &&
- !(xstate->xsave_hdr.xstate_bv & XSTATE_FP))
- return;
-
- if (unlikely(fx->swd & X87_FSW_ES))
- asm volatile("fnclex");
- alternative_input(ASM_NOP8 ASM_NOP2,
- " emms\n" /* clear stack tags */
- " fildl %%gs:0", /* load to clear state */
- X86_FEATURE_FXSAVE_LEAK);
-}
-
-static inline void clear_fpu_state(struct task_struct *tsk)
-{
- fpu_clear(&tsk->thread.fpu);
-}
-
static inline int fxsave_user(struct i387_fxsave_struct __user *fx)
{
int err;
@@ -188,16 +158,6 @@ static inline void fpu_fxsave(struct fpu *fpu)
: [fx] "R" (&fpu->state->fxsave));
}

-static inline void fpu_save_init(struct fpu *fpu)
-{
- if (use_xsave())
- fpu_xsave(fpu);
- else
- fpu_fxsave(fpu);
-
- fpu_clear(fpu);
-}
-
#else /* CONFIG_X86_32 */

/* perform fxrstor iff the processor has extended states, otherwise frstor */
@@ -222,6 +182,8 @@ static inline void fpu_fxsave(struct fpu *fpu)
: [fx] "=m" (fpu->state->fxsave));
}

+#endif /* CONFIG_X86_64 */
+
/* We need a safe address that is cheap to find and that is already
in L1 during context switch. The best choices are unfortunately
different for UP and SMP */
@@ -259,15 +221,13 @@ static inline void fpu_save_init(struct fpu *fpu)
is pending. Clear the x87 state here by setting it to fixed
values. safe_address is a random variable that should be in L1 */
alternative_input(
- GENERIC_NOP8 GENERIC_NOP2,
+ ASM_NOP8 ASM_NOP2,
"emms\n\t" /* clear stack tags */
- "fildl %[addr]", /* set F?P to defined value */
+ "fildl %P[addr]", /* set F?P to defined value */
X86_FEATURE_FXSAVE_LEAK,
[addr] "m" (safe_address));
}

-#endif /* CONFIG_X86_64 */
-
static inline void __save_init_fpu(struct task_struct *tsk)
{
fpu_save_init(&tsk->thread.fpu);
--
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