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powerpc: Remove UP only lazy floating point and vector optimisations

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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>
This commit is contained in:
Anton Blanchard
2015-10-29 11:43:57 +11:00
committed by Michael Ellerman
parent 68bfa962bf
commit af1bbc3dd3
9 changed files with 1 additions and 304 deletions
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18
arch/powerpc/kernel/signal_32.c
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@ -687,15 +687,6 @@ static long restore_user_regs(struct pt_regs *regs,
if (sig)
regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
/*
* Do this before updating the thread state in
* current->thread.fpr/vr/evr. That way, if we get preempted
* and another task grabs the FPU/Altivec/SPE, it won't be
* tempted to save the current CPU state into the thread_struct
* and corrupt what we are writing there.
*/
discard_lazy_cpu_state();
#ifdef CONFIG_ALTIVEC
/*
* Force the process to reload the altivec registers from
@ -798,15 +789,6 @@ static long restore_tm_user_regs(struct pt_regs *regs,
/* Restore the previous little-endian mode */
regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
/*
* Do this before updating the thread state in
* current->thread.fpr/vr/evr. That way, if we get preempted
* and another task grabs the FPU/Altivec/SPE, it won't be
* tempted to save the current CPU state into the thread_struct
* and corrupt what we are writing there.
*/
discard_lazy_cpu_state();
#ifdef CONFIG_ALTIVEC
regs->msr &= ~MSR_VEC;
if (msr & MSR_VEC) {