From patchwork Thu Jan 8 19:44:19 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 1409 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n08JesiJ022518 for ; Thu, 8 Jan 2009 11:40:55 -0800 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750905AbZAHTod (ORCPT ); Thu, 8 Jan 2009 14:44:33 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752282AbZAHTod (ORCPT ); Thu, 8 Jan 2009 14:44:33 -0500 Received: from mx2.redhat.com ([66.187.237.31]:51261 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750905AbZAHToc (ORCPT ); Thu, 8 Jan 2009 14:44:32 -0500 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n08JiPKv019485 for ; Thu, 8 Jan 2009 14:44:26 -0500 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n08JiPWk022625; Thu, 8 Jan 2009 14:44:26 -0500 Received: from amt.cnet (vpn-10-46.str.redhat.com [10.32.10.46]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n08JiN5X007743; Thu, 8 Jan 2009 14:44:24 -0500 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 9D7C1680217; Thu, 8 Jan 2009 17:44:20 -0200 (BRST) Received: (from marcelo@localhost) by amt.cnet (8.14.3/8.14.3/Submit) id n08JiJ9N008199; Thu, 8 Jan 2009 17:44:19 -0200 Date: Thu, 8 Jan 2009 17:44:19 -0200 From: Marcelo Tosatti To: Avi Kivity Cc: kvm-devel Subject: KVM: MMU: drop zeroing on mmu_memory_cache_alloc Message-ID: <20090108194419.GA8176@amt.cnet> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Zeroing on mmu_memory_cache_alloc is unnecessary since: - Smaller areas are pre-allocated with kmem_cache_zalloc. - Page pointed by ->spt is overwritten with prefetch_page and entries in page pointed by ->gfns are initialized before reading. [avi: zeroing pages is unnecessary] Signed-off-by: Marcelo Tosatti --- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 10bdb2a..823d0cd 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -352,7 +352,6 @@ static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc, BUG_ON(!mc->nobjs); p = mc->objects[--mc->nobjs]; - memset(p, 0, size); return p; }