From df08bd10266ce6132278f6b4ddc4bb0a12330b56 Mon Sep 17 00:00:00 2001 From: Alexander Graf Date: Thu, 5 Aug 2010 15:44:41 +0200 Subject: [PATCH] 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 +++++++++++++++++---- arch/powerpc/kernel/kvm_emul.S | 8 +++++++- 2 files changed, 24 insertions(+), 5 deletions(-) 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: diff --git a/arch/powerpc/kernel/kvm_emul.S b/arch/powerpc/kernel/kvm_emul.S index 65305325250b..f2b1b2523e61 100644 --- a/arch/powerpc/kernel/kvm_emul.S +++ b/arch/powerpc/kernel/kvm_emul.S @@ -78,7 +78,8 @@ kvm_emulate_mtmsrd: /* OR the register's (MSR_EE|MSR_RI) on MSR */ kvm_emulate_mtmsrd_reg: - andi. r30, r0, (MSR_EE|MSR_RI) + ori r30, r0, 0 + andi. r30, r30, (MSR_EE|MSR_RI) or r31, r31, r30 /* Put MSR back into magic page */ @@ -96,6 +97,7 @@ kvm_emulate_mtmsrd_reg: SCRATCH_RESTORE /* Nag hypervisor */ +kvm_emulate_mtmsrd_orig_ins: tlbsync b kvm_emulate_mtmsrd_branch @@ -117,6 +119,10 @@ kvm_emulate_mtmsrd_branch_offs: kvm_emulate_mtmsrd_reg_offs: .long (kvm_emulate_mtmsrd_reg - kvm_emulate_mtmsrd) / 4 +.global kvm_emulate_mtmsrd_orig_ins_offs +kvm_emulate_mtmsrd_orig_ins_offs: + .long (kvm_emulate_mtmsrd_orig_ins - kvm_emulate_mtmsrd) / 4 + .global kvm_emulate_mtmsrd_len kvm_emulate_mtmsrd_len: .long (kvm_emulate_mtmsrd_end - kvm_emulate_mtmsrd) / 4 -- 2.20.1