From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E217FC433E1 for ; Mon, 22 Jun 2020 20:11:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C71D820767 for ; Mon, 22 Jun 2020 20:11:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730862AbgFVUKy (ORCPT ); Mon, 22 Jun 2020 16:10:54 -0400 Received: from mga12.intel.com ([192.55.52.136]:60218 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730616AbgFVUJQ (ORCPT ); Mon, 22 Jun 2020 16:09:16 -0400 IronPort-SDR: +xuQJMjh3PXNsG2Re7levRsnwXHdP6/JF1+6vP6CWmqongtoRXOXf3bXwoyejOMEvL/tJCDIJZ FaHZJn3JxU4w== X-IronPort-AV: E=McAfee;i="6000,8403,9660"; a="123527746" X-IronPort-AV: E=Sophos;i="5.75,268,1589266800"; d="scan'208";a="123527746" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jun 2020 13:09:16 -0700 IronPort-SDR: w4y4RhIxwywK7gLZhcnZ8zJZ2/tmsaEeOuzYXpKDxFqbOfafiMe34xl3o0yCJyETNVLXHqptHz oWXxrnFLUUEQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,268,1589266800"; d="scan'208";a="318877091" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.152]) by FMSMGA003.fm.intel.com with ESMTP; 22 Jun 2020 13:09:15 -0700 From: Sean Christopherson To: Marc Zyngier , Paolo Bonzini , Arnd Bergmann Cc: James Morse , Julien Thierry , Suzuki K Poulose , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm@vger.kernel.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, Ben Gardon , Peter Feiner , Peter Shier , Junaid Shahid , Christoffer Dall Subject: [PATCH v2 11/21] KVM: x86/mmu: Zero allocate shadow pages (outside of mmu_lock) Date: Mon, 22 Jun 2020 13:08:12 -0700 Message-Id: <20200622200822.4426-12-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200622200822.4426-1-sean.j.christopherson@intel.com> References: <20200622200822.4426-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Set __GFP_ZERO for the shadow page memory cache and drop the explicit clear_page() from kvm_mmu_get_page(). This moves the cost of zeroing a page to the allocation time of the physical page, i.e. when topping up the memory caches, and thus avoids having to zero out an entire page while holding mmu_lock. Cc: Peter Feiner Cc: Peter Shier Cc: Junaid Shahid Cc: Jim Mattson Suggested-by: Ben Gardon Reviewed-by: Ben Gardon Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 6b0ec9060786..a8f8eebf67df 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -2545,7 +2545,6 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, if (level > PG_LEVEL_4K && need_sync) flush |= kvm_sync_pages(vcpu, gfn, &invalid_list); } - clear_page(sp->spt); trace_kvm_mmu_get_page(sp, true); kvm_mmu_flush_or_zap(vcpu, &invalid_list, false, flush); @@ -5687,6 +5686,8 @@ int kvm_mmu_create(struct kvm_vcpu *vcpu) vcpu->arch.mmu_page_header_cache.kmem_cache = mmu_page_header_cache; vcpu->arch.mmu_page_header_cache.gfp_zero = __GFP_ZERO; + vcpu->arch.mmu_shadow_page_cache.gfp_zero = __GFP_ZERO; + vcpu->arch.mmu = &vcpu->arch.root_mmu; vcpu->arch.walk_mmu = &vcpu->arch.root_mmu; -- 2.26.0