From df08bd10266ce6132278f6b4ddc4bb0a12330b56 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Thu, 5 Aug 2010 15:44:41 +0200 Subject: KVM: PPC: Make PV mtmsrd L=1 work with r30 and r31 We had an arbitrary limitation in mtmsrd L=1 that kept us from using r30 and r31 as input registers. Let's get rid of that and get more potential speedups! Signed-off-by: Alexander Graf --- arch/powerpc/kernel/kvm.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/kernel/kvm.c') diff --git a/arch/powerpc/kernel/kvm.c b/arch/powerpc/kernel/kvm.c index 10b681c092ed..48a033865410 100644 --- a/arch/powerpc/kernel/kvm.c +++ b/arch/powerpc/kernel/kvm.c @@ -158,6 +158,7 @@ static u32 *kvm_alloc(int len) extern u32 kvm_emulate_mtmsrd_branch_offs; extern u32 kvm_emulate_mtmsrd_reg_offs; +extern u32 kvm_emulate_mtmsrd_orig_ins_offs; extern u32 kvm_emulate_mtmsrd_len; extern u32 kvm_emulate_mtmsrd[]; @@ -186,7 +187,21 @@ static void kvm_patch_ins_mtmsrd(u32 *inst, u32 rt) /* Modify the chunk to fit the invocation */ memcpy(p, kvm_emulate_mtmsrd, kvm_emulate_mtmsrd_len * 4); p[kvm_emulate_mtmsrd_branch_offs] |= distance_end & KVM_INST_B_MASK; - p[kvm_emulate_mtmsrd_reg_offs] |= rt; + switch (get_rt(rt)) { + case 30: + kvm_patch_ins_ll(&p[kvm_emulate_mtmsrd_reg_offs], + magic_var(scratch2), KVM_RT_30); + break; + case 31: + kvm_patch_ins_ll(&p[kvm_emulate_mtmsrd_reg_offs], + magic_var(scratch1), KVM_RT_30); + break; + default: + p[kvm_emulate_mtmsrd_reg_offs] |= rt; + break; + } + + p[kvm_emulate_mtmsrd_orig_ins_offs] = *inst; flush_icache_range((ulong)p, (ulong)p + kvm_emulate_mtmsrd_len * 4); /* Patch the invocation */ @@ -423,9 +438,7 @@ static void kvm_check_ins(u32 *inst, u32 features) /* Rewrites */ case KVM_INST_MTMSRD_L1: - /* We use r30 and r31 during the hook */ - if (get_rt(inst_rt) < 30) - kvm_patch_ins_mtmsrd(inst, inst_rt); + kvm_patch_ins_mtmsrd(inst, inst_rt); break; case KVM_INST_MTMSR: case KVM_INST_MTMSRD_L0: -- cgit v1.2.3