diff options
| author | Kevin Hao <haokexin@gmail.com> | 2013-07-14 17:02:05 +0800 |
|---|---|---|
| committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2013-08-14 14:59:44 +1000 |
| commit | 037f0eed57c3f35367ac32275e45f24e297549e9 (patch) | |
| tree | 87dbec64efb721dae5fd8b0a5c2b634f882631dd /arch/powerpc/include/asm/switch_to.h | |
| parent | 662499d04b6bc73d0ecab0ab876bacd5bbe7d6a7 (diff) | |
powerpc: Make flush_fp_to_thread() nop when CONFIG_PPC_FPU is disabled
In the current kernel, the function flush_fp_to_thread() is not
dependent on CONFIG_PPC_FPU. So most invocations of this function
is not wrapped by CONFIG_PPC_FPU. Even through we don't really
save the FPRs to the thread struct if CONFIG_PPC_FPU is not enabled,
but there does have some runtime overhead such as the check for
tsk->thread.regs and preempt disable and enable. It really make
no sense to do that. So make it a nop when CONFIG_PPC_FPU is
disabled. Also remove the wrapped #ifdef CONFIG_PPC_FPU
when invoking this function.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/include/asm/switch_to.h')
| -rw-r--r-- | arch/powerpc/include/asm/switch_to.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 33e1cd823585..39cf0f6cc373 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -19,7 +19,6 @@ extern struct task_struct *_switch(struct thread_struct *prev, extern void giveup_fpu(struct task_struct *); extern void load_up_fpu(void); extern void enable_kernel_fp(void); -extern void flush_fp_to_thread(struct task_struct *); extern void enable_kernel_altivec(void); extern void load_up_altivec(struct task_struct *); extern int emulate_altivec(struct pt_regs *); @@ -37,6 +36,12 @@ static inline void discard_lazy_cpu_state(void) } #endif +#ifdef CONFIG_PPC_FPU +extern void flush_fp_to_thread(struct task_struct *); +#else +static inline void flush_fp_to_thread(struct task_struct *t) { } +#endif + #ifdef CONFIG_ALTIVEC extern void flush_altivec_to_thread(struct task_struct *); extern void giveup_altivec(struct task_struct *); |