From patchwork Wed Aug 7 06:56:05 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Mackerras X-Patchwork-Id: 265351 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 000772C0180 for ; Wed, 7 Aug 2013 16:57:09 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932088Ab3HGG5J (ORCPT ); Wed, 7 Aug 2013 02:57:09 -0400 Received: from ozlabs.org ([203.10.76.45]:39863 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757206Ab3HGG5H (ORCPT ); Wed, 7 Aug 2013 02:57:07 -0400 Received: by ozlabs.org (Postfix, from userid 1003) id 042572C015C; Wed, 7 Aug 2013 16:57:05 +1000 (EST) Date: Wed, 7 Aug 2013 16:56:05 +1000 From: Paul Mackerras To: Alexander Graf , Benjamin Herrenschmidt Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH RFC 5/5] KVM: PPC: Book3S: Load/save FP/VMX/VSX state directly to/from vcpu struct Message-ID: <20130807065605.GK31007@iris.ozlabs.ibm.com> References: <20130807065220.GF31007@iris.ozlabs.ibm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130807065220.GF31007@iris.ozlabs.ibm.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org Now that we have the vcpu floating-point and vector state stored in the same type of struct as the main kernel uses, we can load that state directly from the vcpu struct instead of having extra copies to/from the thread_struct. Similarly, when the guest state needs to be saved, we can have it saved it directly to the vcpu struct by setting the current->thread.fp_save_area and current->thread.vr_save_area pointers. That also means that we don't need to back up and restore userspace's FP/vector state. This all makes the code simpler and faster. Note that it's not necessary to save or modify current->thread.fpexc_mode, since nothing in KVM uses or is affected by its value. Nor is it necessary to touch used_vr or used_vsr. Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_pr.c | 72 ++++++++++---------------------------------- arch/powerpc/kvm/booke.c | 16 ---------- arch/powerpc/kvm/booke.h | 4 ++- 3 files changed, 19 insertions(+), 73 deletions(-) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index fccbadf..df7d0ac 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -558,16 +558,16 @@ void kvmppc_giveup_ext(struct kvm_vcpu *vcpu, ulong msr) * both the traditional FP registers and the added VSX * registers into thread.fp_state.fpr[]. */ - if (current->thread.regs->msr & MSR_FP) + if (t->regs->msr & MSR_FP) giveup_fpu(current); - vcpu->arch.fp = t->fp_state; + t->fp_save_area = NULL; } #ifdef CONFIG_ALTIVEC if (msr & MSR_VEC) { if (current->thread.regs->msr & MSR_VEC) giveup_altivec(current); - vcpu->arch.vr = t->vr_state; + t->vr_save_area = NULL; } #endif @@ -652,22 +652,20 @@ static int kvmppc_handle_ext(struct kvm_vcpu *vcpu, unsigned int exit_nr, #endif if (msr & MSR_FP) { - t->fp_state = vcpu->arch.fp; - t->fpexc_mode = 0; enable_kernel_fp(); - load_fp_state(&t->fp_state); + load_fp_state(&vcpu->arch.fp); + t->fp_save_area = &vcpu->arch.fp; } if (msr & MSR_VEC) { #ifdef CONFIG_ALTIVEC - t->vr_state = vcpu->arch.vr; - t->vrsave = -1; enable_kernel_altivec(); - load_vr_state(&t->vr_state); + load_vr_state(&vcpu->arch.vr); + t->vr_save_area = &vcpu->arch.vr; #endif } - current->thread.regs->msr |= msr; + t->regs->msr |= msr; vcpu->arch.guest_owned_ext |= msr; kvmppc_recalc_shadow_msr(vcpu); @@ -688,11 +686,11 @@ static void kvmppc_handle_lost_ext(struct kvm_vcpu *vcpu) if (lost_ext & MSR_FP) { enable_kernel_fp(); - load_fp_state(¤t->thread.fp_state); + load_fp_state(&vcpu->arch.fp); } if (lost_ext & MSR_VEC) { enable_kernel_altivec(); - load_vr_state(¤t->thread.vr_state); + load_vr_state(&vcpu->arch.vr); } current->thread.regs->msr |= lost_ext; } @@ -1249,17 +1247,9 @@ static void enable_relon_interrupts(struct kvm *kvm) int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) { int ret; - struct thread_fp_state fp; - int fpexc_mode; #ifdef CONFIG_ALTIVEC - struct thread_vr_state vr; unsigned long uninitialized_var(vrsave); - int used_vr; #endif -#ifdef CONFIG_VSX - int used_vsr; -#endif - ulong ext_msr; /* Check if we can run the vcpu at all */ if (!vcpu->arch.sane) { @@ -1284,33 +1274,22 @@ int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) if (!vcpu->kvm->arch.relon_disabled) disable_relon_interrupts(vcpu->kvm); - /* Save FPU state in stack */ + /* Save FPU state in thread_struct */ if (current->thread.regs->msr & MSR_FP) giveup_fpu(current); - fp = current->thread.fp_state; - fpexc_mode = current->thread.fpexc_mode; #ifdef CONFIG_ALTIVEC - /* Save Altivec state in stack */ - used_vr = current->thread.used_vr; - if (used_vr) { - if (current->thread.regs->msr & MSR_VEC) - giveup_altivec(current); - vr = current->thread.vr_state; - vrsave = current->thread.vrsave; - } + /* Save Altivec state in thread_struct */ + if (current->thread.regs->msr & MSR_VEC) + giveup_altivec(current); #endif #ifdef CONFIG_VSX - /* Save VSX state in stack */ - used_vsr = current->thread.used_vsr; - if (used_vsr && (current->thread.regs->msr & MSR_VSX)) + /* Save VSX state in thread_struct */ + if (current->thread.regs->msr & MSR_VSX) __giveup_vsx(current); #endif - /* Remember the MSR with disabled extensions */ - ext_msr = current->thread.regs->msr; - /* Preload FPU if it's enabled */ if (vcpu->arch.shared->msr & MSR_FP) kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP); @@ -1325,25 +1304,6 @@ int kvmppc_vcpu_run_pr(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) /* Make sure we save the guest FPU/Altivec/VSX state */ kvmppc_giveup_ext(vcpu, MSR_FP | MSR_VEC | MSR_VSX); - current->thread.regs->msr = ext_msr; - - /* Restore FPU/VSX state from stack */ - current->thread.fp_state = fp; - current->thread.fpexc_mode = fpexc_mode; - -#ifdef CONFIG_ALTIVEC - /* Restore Altivec state from stack */ - if (used_vr && current->thread.used_vr) { - current->thread.vr_state = vr; - current->thread.vrsave = vrsave; - } - current->thread.used_vr = used_vr; -#endif - -#ifdef CONFIG_VSX - current->thread.used_vsr = used_vsr; -#endif - out: vcpu->mode = OUTSIDE_GUEST_MODE; return ret; diff --git a/arch/powerpc/kvm/booke.c b/arch/powerpc/kvm/booke.c index 4998a65..34ae14e 100644 --- a/arch/powerpc/kvm/booke.c +++ b/arch/powerpc/kvm/booke.c @@ -655,10 +655,6 @@ int kvmppc_core_check_requests(struct kvm_vcpu *vcpu) int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) { int ret, s; -#ifdef CONFIG_PPC_FPU - struct thread_fp_state fp; - int fpexc_mode; -#endif if (!vcpu->arch.sane) { kvm_run->exit_reason = KVM_EXIT_INTERNAL_ERROR; @@ -676,11 +672,6 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) #ifdef CONFIG_PPC_FPU /* Save userspace FPU state in stack */ enable_kernel_fp(); - fp = current->thread.fp_state; - fpexc_mode = current->thread.fpexc_mode; - - /* Restore guest FPU state to thread */ - current->thread.fp_state = vcpu->arch.fp; /* * Since we can't trap on MSR_FP in GS-mode, we consider the guest @@ -704,13 +695,6 @@ int kvmppc_vcpu_run(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) kvmppc_save_guest_fp(vcpu); vcpu->fpu_active = 0; - - /* Save guest FPU state from thread */ - vcpu->arch.fp = current->thread.fp_state; - - /* Restore userspace FPU state from stack */ - current->thread.fp_state = fp; - current->thread.fpexc_mode = fpexc_mode; #endif out: diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h index 7ffb699..4aab5cf 100644 --- a/arch/powerpc/kvm/booke.h +++ b/arch/powerpc/kvm/booke.h @@ -113,7 +113,8 @@ static inline void kvmppc_load_guest_fp(struct kvm_vcpu *vcpu) #ifdef CONFIG_PPC_FPU if (vcpu->fpu_active && !(current->thread.regs->msr & MSR_FP)) { enable_kernel_fp(); - load_fp_state(¤t->thread.fp_state); + load_fp_state(&vcpu->arch.fp); + current->thread.fp_save_area = &vcpu->arch.fp; current->thread.regs->msr |= MSR_FP; } #endif @@ -128,6 +129,7 @@ static inline void kvmppc_save_guest_fp(struct kvm_vcpu *vcpu) #ifdef CONFIG_PPC_FPU if (vcpu->fpu_active && (current->thread.regs->msr & MSR_FP)) giveup_fpu(current); + current->thread.fp_save_area = NULL; #endif } #endif /* __KVM_BOOKE_H__ */