From c208505900b232ecdc81dee54cb3a032e75d88d6 Mon Sep 17 00:00:00 2001 From: Anton Blanchard Date: Thu, 29 Oct 2015 11:44:08 +1100 Subject: 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 [mpe: giveup_all() needs to be EXPORT_SYMBOL'ed] Signed-off-by: Michael Ellerman --- arch/powerpc/kvm/book3s_pr.c | 17 ++--------------- 1 file changed, 2 insertions(+), 15 deletions(-) (limited to 'arch/powerpc/kvm/book3s_pr.c') diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index 49f5dad1bd45..a78e0e6bd932 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -1490,21 +1490,8 @@ static int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) goto out; /* interrupts now hard-disabled */ - /* Save FPU state in thread_struct */ - if (current->thread.regs->msr & MSR_FP) - giveup_fpu(current); - -#ifdef CONFIG_ALTIVEC - /* Save Altivec state in thread_struct */ - if (current->thread.regs->msr & MSR_VEC) - giveup_altivec(current); -#endif - -#ifdef CONFIG_VSX - /* Save VSX state in thread_struct */ - if (current->thread.regs->msr & MSR_VSX) - __giveup_vsx(current); -#endif + /* Save FPU, Altivec and VSX state */ + giveup_all(current); /* Preload FPU if it's enabled */ if (kvmppc_get_msr(vcpu) & MSR_FP) -- cgit v1.2.3-59-g8ed1b