From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Jones Subject: [RFC PATCH 6/6] KVM: ARM: no need for kvm_arch_flush_incoherent Date: Fri, 6 Mar 2015 13:52:33 -0500 Message-ID: <1425667953-3566-7-git-send-email-drjones@redhat.com> References: <1425667780-3449-1-git-send-email-drjones@redhat.com> <1425667953-3566-1-git-send-email-drjones@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id DE93F47FE2 for ; Fri, 6 Mar 2015 13:46:41 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HqSOj5b6uS6k for ; Fri, 6 Mar 2015 13:46:41 -0500 (EST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 0E2FF47FF5 for ; Fri, 6 Mar 2015 13:46:40 -0500 (EST) In-Reply-To: <1425667953-3566-1-git-send-email-drjones@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: kvmarm@lists.cs.columbia.edu, qemu-devel@nongnu.org, ard.biesheuvel@linaro.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, peter.maydell@linaro.org Cc: pbonzini@redhat.com, lersek@redhat.com, catalin.marinas@arm.com List-Id: kvmarm@lists.cs.columbia.edu kvm_arch_flush_incoherent makes things too slow, and we don't need it. Userspace can flush for us, as the necessary cache maintenance instruction is not (necessarily) privileged. Signed-off-by: Andrew Jones --- arch/arm/kvm/mmu.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 2f45db9cd436a..b2d87587a9d79 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -1822,6 +1822,11 @@ int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, void kvm_arch_flush_incoherent(struct kvm *kvm, struct kvm_memory_slot *slot) { + /* + * We no longer need this function, now that userspace does the + * flushing. + */ +#if 0 if (slot->flags & KVM_MEM_READONLY) { /* * Readonly memory shouldn't be changing, and we do a @@ -1840,6 +1845,7 @@ void kvm_arch_flush_incoherent(struct kvm *kvm, struct kvm_memory_slot *slot) */ coherent_cache_memslot(slot, true); +#endif } void kvm_arch_invalidate_incoherent(struct kvm *kvm, struct kvm_memory_slot *slot) -- 1.8.3.1