diff options
| author | Anton Blanchard <anton@samba.org> | 2015-10-29 11:43:57 +1100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2015-12-01 13:52:24 +1100 |
| commit | af1bbc3dd3d501d27da72e1764afe5f5b0d3882d (patch) | |
| tree | 99e12a987162dce90c51b7f7ccb2b3e23b154c4b /arch/powerpc/kernel/head_fsl_booke.S | |
| parent | 68bfa962bff5783ad65de9dc7f3b9e16ea466766 (diff) | |
powerpc: Remove UP only lazy floating point and vector optimisations
The UP only lazy floating point and vector optimisations were written
back when SMP was not common, and neither glibc nor gcc used vector
instructions. Now SMP is very common, glibc aggressively uses vector
instructions and gcc autovectorises.
We want to add new optimisations that apply to both UP and SMP, but
in preparation for that remove these UP only optimisations.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/head_fsl_booke.S')
| -rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 32 |
1 files changed, 0 insertions, 32 deletions
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index fffd1f96bb1d..ec936abbcadc 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -857,29 +857,6 @@ _GLOBAL(load_up_spe) oris r5,r5,MSR_SPE@h mtmsr r5 /* enable use of SPE now */ isync -/* - * For SMP, we don't do lazy SPE switching because it just gets too - * horrendously complex, especially when a task switches from one CPU - * to another. Instead we call giveup_spe in switch_to. - */ -#ifndef CONFIG_SMP - lis r3,last_task_used_spe@ha - lwz r4,last_task_used_spe@l(r3) - cmpi 0,r4,0 - beq 1f - addi r4,r4,THREAD /* want THREAD of last_task_used_spe */ - SAVE_32EVRS(0,r10,r4,THREAD_EVR0) - evxor evr10, evr10, evr10 /* clear out evr10 */ - evmwumiaa evr10, evr10, evr10 /* evr10 <- ACC = 0 * 0 + ACC */ - li r5,THREAD_ACC - evstddx evr10, r4, r5 /* save off accumulator */ - lwz r5,PT_REGS(r4) - lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5) - lis r10,MSR_SPE@h - andc r4,r4,r10 /* disable SPE for previous task */ - stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) -1: -#endif /* !CONFIG_SMP */ /* enable use of SPE after return */ oris r9,r9,MSR_SPE@h mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */ @@ -889,10 +866,6 @@ _GLOBAL(load_up_spe) evlddx evr4,r10,r5 evmra evr4,evr4 REST_32EVRS(0,r10,r5,THREAD_EVR0) -#ifndef CONFIG_SMP - subi r4,r5,THREAD - stw r4,last_task_used_spe@l(r3) -#endif /* !CONFIG_SMP */ blr /* @@ -1035,11 +1008,6 @@ _GLOBAL(giveup_spe) andc r4,r4,r3 /* disable SPE for previous task */ stw r4,_MSR-STACK_FRAME_OVERHEAD(r5) 1: -#ifndef CONFIG_SMP - li r5,0 - lis r4,last_task_used_spe@ha - stw r5,last_task_used_spe@l(r4) -#endif /* !CONFIG_SMP */ blr #endif /* CONFIG_SPE */ |