diff options
| author | Anton Blanchard <anton@samba.org> | 2015-10-29 03:44:08 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2015-12-02 11:34:26 +0300 |
| commit | c208505900b232ecdc81dee54cb3a032e75d88d6 (patch) | |
| tree | e63fe696c5a8404bc4257204502f0d6f9ed3ccaf /arch/powerpc/include/asm/switch_to.h | |
| parent | 1f2e25b2d552cade43eacb2edc4e7f01c1cfecb3 (diff) | |
| download | linux-c208505900b232ecdc81dee54cb3a032e75d88d6.tar.xz | |
powerpc: create giveup_all()
Create a single function that gives everything up (FP, VMX, VSX, SPE).
Doing this all at once means we only do one MSR write.
A context switch microbenchmark using yield():
http://ozlabs.org/~anton/junkcode/context_switch2.c
./context_switch2 --test=yield --fp --altivec --vector 0 0
shows an improvement of 3% on POWER8.
Signed-off-by: Anton Blanchard <anton@samba.org>
[mpe: giveup_all() needs to be EXPORT_SYMBOL'ed]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/include/asm/switch_to.h')
| -rw-r--r-- | arch/powerpc/include/asm/switch_to.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h index 9414dcb180d6..8f856788a7cf 100644 --- a/arch/powerpc/include/asm/switch_to.h +++ b/arch/powerpc/include/asm/switch_to.h @@ -26,6 +26,7 @@ extern void __giveup_vsx(struct task_struct *); extern void giveup_vsx(struct task_struct *); extern void enable_kernel_spe(void); extern void load_up_spe(struct task_struct *); +extern void giveup_all(struct task_struct *); extern void switch_booke_debug_regs(struct debug_reg *new_debug); #ifdef CONFIG_PPC_FPU |