From patchwork Fri Oct 16 07:07:45 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Denis V. Lunev" X-Patchwork-Id: 7411181 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 14E8D9F36A for ; Fri, 16 Oct 2015 07:08:38 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 4574C2074E for ; Fri, 16 Oct 2015 07:08:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 49E7720748 for ; Fri, 16 Oct 2015 07:08:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753481AbbJPHI1 (ORCPT ); Fri, 16 Oct 2015 03:08:27 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:22712 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753061AbbJPHIZ (ORCPT ); Fri, 16 Oct 2015 03:08:25 -0400 Received: from hades.sw.ru ([10.30.8.132]) by relay.sw.ru (8.13.4/8.13.4) with ESMTP id t9G77rsL016638; Fri, 16 Oct 2015 10:07:58 +0300 (MSK) From: "Denis V. Lunev" Cc: rkagan@virtuozzo.com, virtualization@lists.linux-foundation.org, qemu-devel@nongnu.org, kvm@vger.kernel.org, Andrey Smetanin , "Denis V. Lunev" , Vitaly Kuznetsov , "K. Y. Srinivasan" , Gleb Natapov , Paolo Bonzini Subject: [PATCH 1/9] kvm/eventfd: avoid loop inside irqfd_update() Date: Fri, 16 Oct 2015 10:07:45 +0300 Message-Id: <1444979273-6587-2-git-send-email-den@openvz.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1444979273-6587-1-git-send-email-den@openvz.org> References: <1444979273-6587-1-git-send-email-den@openvz.org> To: unlisted-recipients:; (no To-header on input) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Andrey Smetanin The loop(for) inside irqfd_update() is unnecessary because any other value for irq_entry.type will just trigger schedule_work(&irqfd->inject). Signed-off-by: Andrey Smetanin Reviewed-by: Roman Kagan Signed-off-by: Denis V. Lunev CC: Vitaly Kuznetsov CC: "K. Y. Srinivasan" CC: Gleb Natapov CC: Paolo Bonzini --- virt/kvm/eventfd.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index b637965..518421e 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -238,20 +238,17 @@ static void irqfd_update(struct kvm *kvm, struct kvm_kernel_irqfd *irqfd) { struct kvm_kernel_irq_routing_entry *e; struct kvm_kernel_irq_routing_entry entries[KVM_NR_IRQCHIPS]; - int i, n_entries; + int n_entries; n_entries = kvm_irq_map_gsi(kvm, entries, irqfd->gsi); write_seqcount_begin(&irqfd->irq_entry_sc); - irqfd->irq_entry.type = 0; - e = entries; - for (i = 0; i < n_entries; ++i, ++e) { - /* Only fast-path MSI. */ - if (e->type == KVM_IRQ_ROUTING_MSI) - irqfd->irq_entry = *e; - } + if (n_entries == 1) + irqfd->irq_entry = *e; + else + irqfd->irq_entry.type = 0; write_seqcount_end(&irqfd->irq_entry_sc); }