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x86/fpu: Uninline kernel_fpu_begin()/end()

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Both inline functions call an inline function unconditionally, so we
already pay the function call based clobbering cost. Uninline them.

This saves quite a bit of code in various performance sensitive
code paths:

   text            data    bss     dec             hex     filename
   13321334        2569888 1634304 17525526        10b6b16 vmlinux.before
   13320246        2569888 1634304 17524438        10b66d6 vmlinux.after

Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Ingo Molnar 2015-04-26 12:07:18 +02:00
parent e229537543
commit d63e79b114
2 changed files with 17 additions and 13 deletions
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15
arch/x86/include/asm/fpu/api.h
View File

@ -39,19 +39,8 @@ extern bool irq_fpu_usable(void);
*/
extern void __kernel_fpu_begin(void);
extern void __kernel_fpu_end(void);
static inline void kernel_fpu_begin(void)
{
preempt_disable();
WARN_ON_ONCE(!irq_fpu_usable());
__kernel_fpu_begin();
}
static inline void kernel_fpu_end(void)
{
__kernel_fpu_end();
preempt_enable();
}
extern void kernel_fpu_begin(void);
extern void kernel_fpu_end(void);
/*
* Some instructions like VIA's padlock instructions generate a spurious

15
arch/x86/kernel/fpu/core.c
View File

@ -125,6 +125,21 @@ void __kernel_fpu_end(void)
}
EXPORT_SYMBOL(__kernel_fpu_end);
void kernel_fpu_begin(void)
{
preempt_disable();
WARN_ON_ONCE(!irq_fpu_usable());
__kernel_fpu_begin();
}
EXPORT_SYMBOL_GPL(kernel_fpu_begin);
void kernel_fpu_end(void)
{
__kernel_fpu_end();
preempt_enable();
}
EXPORT_SYMBOL_GPL(kernel_fpu_end);
static void __save_fpu(struct fpu *fpu)
{
if (use_xsave()) {