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 D56A6C43603 for ; Wed, 18 Dec 2019 04:40:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A64B720715 for ; Wed, 18 Dec 2019 04:40:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="O0yzhS23" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726676AbfLREkW (ORCPT ); Tue, 17 Dec 2019 23:40:22 -0500 Received: from mail-pf1-f196.google.com ([209.85.210.196]:38648 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726594AbfLREkU (ORCPT ); Tue, 17 Dec 2019 23:40:20 -0500 Received: by mail-pf1-f196.google.com with SMTP id x185so495984pfc.5 for ; Tue, 17 Dec 2019 20:40:20 -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=O0yzhS23HGtIJZbs0zAM+mSOkQxGOG6AvwAEalcJQrw8ZovBcuay4V1Al0Dj1xAO1f wVwcbxEVekcuUvSyh+zo6MysMZ5iBMzSPyuDESXnLF9rM2PPdJsmgWA5pMB+8Diot1EN lSQGr0HWcuk9CMYUxTzT93IL2wrD4zOvVqK+OCMm/TxxvRsmeo/R8X13p7tTvk0jwo+f j9Uqkm+lpWXaZU7IkuGF6CpBWm39tcrP5N/RouvlnfyqEr7T1O97IH7dS5E/4zZeiggR nYUMan99mW+H1e5ehvAYcsf1mOavIMEUaJRhZJv0wLFajDCMFAdkVribcE+GJNceDZkj D3NQ== 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=TGENLqkYt8uZ2M7O6lm5ul2xHjA6UqEY6Nfhrk1fFIO7BfMxL4/P5RYnleRj7hdGRg 5r6eV39zqrl1kbbw4TfuSsQ3viMpbZ5P5/qrMDEdbNpn2Xo0vzxZrl+V3aeS2ozhgUT7 UeCDn2b6Hb6W6WmR9/Dtp0KUcGvlcDUqG7op7/GTSt6Lzwh44sZ9vVlOc163WiPmMfuv dkXRqu6bpPVKqEiNj0ouus8rvGqgqiRTMEoZ5FN+Rw6eu1Ey1fp3Supoq3FdiH+m2wAI g/eE7HMUx9BPKAaqzMrmERtFc2+qqneYfTpyQKwEPb0W5+qY2JbEIfpcZ1by+UlAZxf/ mvtw== X-Gm-Message-State: APjAAAVsxU0nSmCb/A33i0NGqoACMONxXiBnHOkZnGdB+lE0sRrYlWiu uyJBE15iHmrTccGT6ZD0vZy/QJxqSPc= X-Google-Smtp-Source: APXvYqzSQ8EkWQ17u7mqdOiOyZaCadH8FPwTAgfdXevSealYbYZ5TAeFeSKvd1+6TyOxHGnOE1UJ0w== X-Received: by 2002:a63:1d1d:: with SMTP id d29mr617092pgd.387.1576644019834; Tue, 17 Dec 2019 20:40:19 -0800 (PST) Received: from tw-172-25-31-76.office.twttr.net ([8.25.197.24]) by smtp.gmail.com with ESMTPSA id j21sm781105pfe.175.2019.12.17.20.40.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Dec 2019 20:40:19 -0800 (PST) From: Cong Wang To: iommu@lists.linux-foundation.org Cc: robin.murphy@arm.com, linux-kernel@vger.kernel.org, joro@8bytes.org, Cong Wang , John Garry Subject: [Patch v3 2/3] iommu: optimize iova_magazine_free_pfns() Date: Tue, 17 Dec 2019 20:39:50 -0800 Message-Id: <20191218043951.10534-3-xiyou.wangcong@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191218043951.10534-1-xiyou.wangcong@gmail.com> References: <20191218043951.10534-1-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