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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35A24ECAAA3 for ; Fri, 26 Aug 2022 10:28:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343532AbiHZK2r (ORCPT ); Fri, 26 Aug 2022 06:28:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245027AbiHZK2p (ORCPT ); Fri, 26 Aug 2022 06:28:45 -0400 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 672DBD0744 for ; Fri, 26 Aug 2022 03:28:44 -0700 (PDT) Received: by mail-pj1-x102c.google.com with SMTP id bg22so1236539pjb.2 for ; Fri, 26 Aug 2022 03:28:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20210112.gappssmtp.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:from:to:cc; bh=U+isRkpz8Ia+KyvGxBChAGkeQyWJ1PdeEmG8QHIxQpk=; b=pmBmgmW6EfkwZCVXRrd/3HA6KvtfblbnSTnHdQZDx+GMtiyR1hGQ7xPetBexTzKs5M q1f6sdE6hPF7/fGmb9GYhXDcLi3XkRLxiGKbr4KZYCwzTARQUXF4wzep/izfhZnwDIWa irpkvVj4LPC9sQzZN1u8t7m28pEaAlH+0T29kbSB2dLPMEyW13Pf83YnPcwUC1hqd187 GFnnb+3Lq1ZO1fB80zJxP2RLX3pJTBwUuGYAZi4MyVV/fvXTPX4eWGiyIteqMb02ldze sWU4qnNNgWO0cI4qzWPvQ8IBtgbHzx5EMVacC/GHn4o1DYM5oCrfMk5wBduhQiFmv7cO gZLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:x-gm-message-state:from:to :cc; bh=U+isRkpz8Ia+KyvGxBChAGkeQyWJ1PdeEmG8QHIxQpk=; b=rF7cs5sTMzTVlu5z9wNBilmB5Hq7EulkRkQV2kl8kpY3vtEzNkH06pvITIWTOD/ORG P/OoSwDxIJNwFUp1Scum12WwaEFG4JHBa182fkGhhoH99YqztSYINgQH8NDeoL3XkL4E RStZu1ctoWSSWTL8NOj5eF+8kdUIxlpVkiN7fz6d+lkGXXzM5oq1PuFnFYbeEBEgrOpw xZf3gEnO5MrDE4RVmm6OW8jb0fT8MPshNisSacbr2huVAb2UYl1iirc3pIFYHkQFwetg TthGaMLmnboSm58xk63qY/D2M2XsGrtYzEViO/aP4M0RwIVC6myd4rYZoPtyVj1oybjW 9ikw== X-Gm-Message-State: ACgBeo0aDmcFLTVkrOzkkRbTvN3XuWQhNOwsNiluMNsp2Fhd21YIagA9 Zfft8GOwCb3vMKvaJOGo00WYddujhDFFqA== X-Google-Smtp-Source: AA6agR6RGF84krP3Bh3Fyw/2zGy4J9zwPYJxbanC7aL9i06l9ZENZAKzD9HHfAt1KWbFF28C4cwrEA== X-Received: by 2002:a17:90b:1e49:b0:1f5:1dbf:4c3a with SMTP id pi9-20020a17090b1e4900b001f51dbf4c3amr3809604pjb.232.1661509723959; Fri, 26 Aug 2022 03:28:43 -0700 (PDT) Received: from [10.71.59.90] ([139.177.225.230]) by smtp.gmail.com with ESMTPSA id x187-20020a6263c4000000b0052dc12cded3sm1300821pfb.196.2022.08.26.03.28.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 26 Aug 2022 03:28:43 -0700 (PDT) Message-ID: <4527c925-076b-a477-4ff8-697d75f16761@bytedance.com> Date: Fri, 26 Aug 2022 18:28:39 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:102.0) Gecko/20100101 Thunderbird/102.2.0 Subject: Re: [PATCH v2] iommu/iova: Optimize alloc_iova with rbtree_augmented To: Ethan Zhao , joro@8bytes.org, will@kernel.org Cc: iommu@lists.linux.dev, linux-kernel@vger.kernel.org, robin.murphy@arm.com References: <20220824095139.66477-1-zhangpeng.00@bytedance.com> <06c215c6-cbae-d6b9-312c-6535e51a3128@linux.intel.com> <486fcde8-e9f5-e40c-db5d-fd3ade59b267@bytedance.com> From: Peng Zhang In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Though only 3-4 drivers use alloc_iova() directly, in my understanding > > your test has simulated the worst case, rcache doesn't work at all, > > "alloc_iova" +“remove_iova” number looks great for worst case. There is another case, when the size to allocate greater to 2^5, even if alloc_iova_fast() is used, alloc_iova() will always be called because the maximum iova size that rcache supports to allocate is 32. IOVA_RANGE_CACHE_MAX_SIZE specifies the maximum size. Thanks, Peng