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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 4909EC3F68F for ; Fri, 6 Dec 2019 21:39:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 180F824673 for ; Fri, 6 Dec 2019 21:39:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TyPQPMqM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726508AbfLFVjB (ORCPT ); Fri, 6 Dec 2019 16:39:01 -0500 Received: from mail-pf1-f194.google.com ([209.85.210.194]:41352 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726480AbfLFVi6 (ORCPT ); Fri, 6 Dec 2019 16:38:58 -0500 Received: by mail-pf1-f194.google.com with SMTP id s18so3995406pfd.8 for ; Fri, 06 Dec 2019 13:38:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=7tnHP49bcbdj6wbVlgmEh/i8N9jDvFKi9kaAZwgRO58=; b=TyPQPMqMEZSbzOq4YJ/CvyzohiFL0nmwcH8xHd7uNVwqdGTgbtf0zTU4yDZK1m7Vyx hlYdg2gEo6eO6NHj76PC38ouj8DYqG4UVvy/IzsnpWtq4/6d27V38a3kSPzQTyRtkR8Y 2M6qvvr0p5NKM43hOouFg3JyFqzJj8i+zZ4l9OaZ89xWFzoA01K5obewearyD4XEXHvc zOIIvRBWygSG4Kst7lrgh+0haf87ZCGEIH/a8AKlLmbyJASFzCV/3fynQziQjZUvx72H TVDQRhfWyvqzoj/HeARTIzz7Qk776PoUSWj/v2R7ml8Voe5PoswscOetD8p5kipOy5gv t7bQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=7tnHP49bcbdj6wbVlgmEh/i8N9jDvFKi9kaAZwgRO58=; b=dW21asuq0H4sn0eMqynwK47tk2PTqo9lRnteo5iDOX4ZPrw7vsySnWsHa7DH7E8iwC LATWDfNnNazLoTKrTC+EDpJGF/W9inl4vWqQsF9km22nkWHWVI0ZkJ/BBE5A59KSRTnw 070EcDlrMlSUJtlu2qPrf5eBZMYerrMhkXjcGh5p8/3idAihUXxOVwGJoZwsI4Ujs3Vf C+TKa0KVhgNyn2Q0UFVvYphRk9RYEFxK1ZaFHYbfeXyKR4OVkynTJdkyIYtMG0B+N9T/ fcjjuvi2/f3iDSo6UfZ2vh757LEfCqI4Nh3cdRsBbtiN6+MH6P+21QOqfUt/2+fUVx32 8VmA== X-Gm-Message-State: APjAAAXPn+g3IFHN548UblntFxJThr9e9gsuEhhoVmUulCTOVc88LOFC sHZe7HT4Ofb+EiwxnwiyWsk= X-Google-Smtp-Source: APXvYqy2mcWYMGqjSshbYvqQi62LTZgqbF8ADTCo4gLwYPawIPjikZb3TSZDYbkVlgy2vV0XN6ksiQ== X-Received: by 2002:a63:5056:: with SMTP id q22mr5820145pgl.20.1575668337654; Fri, 06 Dec 2019 13:38:57 -0800 (PST) Received: from tw-172-25-31-76.office.twttr.net ([8.25.197.24]) by smtp.gmail.com with ESMTPSA id d65sm17368579pfa.159.2019.12.06.13.38.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Dec 2019 13:38:57 -0800 (PST) From: Cong Wang To: iommu@lists.linux-foundation.org Cc: linux-kernel@vger.kernel.org, joro@8bytes.org, Cong Wang , John Garry Subject: [Patch v3 2/3] iommu: optimize iova_magazine_free_pfns() Date: Fri, 6 Dec 2019 13:38:02 -0800 Message-Id: <20191206213803.12580-3-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191206213803.12580-1-xiyou.wangcong@gmail.com> References: <20191206213803.12580-1-xiyou.wangcong@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the magazine is empty, iova_magazine_free_pfns() should be a nop, however it misses the case of mag->size==0. So we should just call iova_magazine_empty(). This should reduce the contention on iovad->iova_rbtree_lock a little bit, not much at all. Cc: Joerg Roedel Cc: John Garry Signed-off-by: Cong Wang --- drivers/iommu/iova.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index cb473ddce4cf..184d4c0e20b5 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -797,13 +797,23 @@ static void iova_magazine_free(struct iova_magazine *mag) kfree(mag); } +static bool iova_magazine_full(struct iova_magazine *mag) +{ + return (mag && mag->size == IOVA_MAG_SIZE); +} + +static bool iova_magazine_empty(struct iova_magazine *mag) +{ + return (!mag || mag->size == 0); +} + static void iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) { unsigned long flags; int i; - if (!mag) + if (iova_magazine_empty(mag)) return; spin_lock_irqsave(&iovad->iova_rbtree_lock, flags); @@ -820,16 +830,6 @@ iova_magazine_free_pfns(struct iova_magazine *mag, struct iova_domain *iovad) mag->size = 0; } -static bool iova_magazine_full(struct iova_magazine *mag) -{ - return (mag && mag->size == IOVA_MAG_SIZE); -} - -static bool iova_magazine_empty(struct iova_magazine *mag) -{ - return (!mag || mag->size == 0); -} - static unsigned long iova_magazine_pop(struct iova_magazine *mag, unsigned long limit_pfn) { -- 2.21.0