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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 3AA11C43215 for ; Fri, 15 Nov 2019 09:09:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1CF362073B for ; Fri, 15 Nov 2019 09:09:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727202AbfKOJJX (ORCPT ); Fri, 15 Nov 2019 04:09:23 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:6234 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725829AbfKOJJX (ORCPT ); Fri, 15 Nov 2019 04:09:23 -0500 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 090D03BEE30B7D809372; Fri, 15 Nov 2019 17:09:21 +0800 (CST) Received: from [127.0.0.1] (10.74.221.148) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.439.0; Fri, 15 Nov 2019 17:09:14 +0800 Subject: Re: [PATCH v3] lib: optimize cpumask_local_spread() To: Michal Hocko References: <1573091048-10595-1-git-send-email-zhangshaokun@hisilicon.com> <20191108103102.GF15658@dhcp22.suse.cz> <20191112115630.GD2763@dhcp22.suse.cz> <00856999-739f-fd73-eddd-d71e4e94962e@hisilicon.com> <20191114144317.GJ20866@dhcp22.suse.cz> CC: , yuqi jin , "Andrew Morton" , Mike Rapoport , "Paul Burton" , Michael Ellerman , Anshuman Khandual , From: Shaokun Zhang Message-ID: <9af13fea-95a6-30cb-2c0e-770aa649a549@hisilicon.com> Date: Fri, 15 Nov 2019 17:09:13 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.1.1 MIME-Version: 1.0 In-Reply-To: <20191114144317.GJ20866@dhcp22.suse.cz> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.74.221.148] X-CFilter-Loop: Reflected Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hi Michal, On 2019/11/14 22:43, Michal Hocko wrote: > On Wed 13-11-19 10:46:05, Shaokun Zhang wrote: > [...] >>>> available: 4 nodes (0-3) >>>> node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 >>>> node 0 size: 63379 MB >>>> node 0 free: 61899 MB >>>> node 1 cpus: 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 >>>> node 1 size: 64509 MB >>>> node 1 free: 63942 MB >>>> node 2 cpus: 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 >>>> node 2 size: 64509 MB >>>> node 2 free: 63056 MB >>>> node 3 cpus: 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 >>>> node 3 size: 63997 MB >>>> node 3 free: 63420 MB >>>> node distances: >>>> node 0 1 2 3 >>>> 0: 10 16 32 33 >>>> 1: 16 10 25 32 >>>> 2: 32 25 10 16 >>>> 3: 33 32 16 10 > [...] >> before patch >> Euler:/sys/bus/pci/devices/0000:7d:00.2 # cat numa_node >> 2 >> Euler:/sys/bus/pci # cat /proc/irq/345/smp_affinity_list >> 48 > > node 2 > >> Euler:/sys/bus/pci # cat /proc/irq/369/smp_affinity_list >> 0 > > node 0 > >> Euler:/sys/bus/pci # cat /proc/irq/393/smp_affinity_list >> 24 > > node 1 > >> Euler:/sys/bus/pci # >> >> after patch >> Euler:/sys/bus/pci/devices/0000:7d:00.2 # cat numa_node >> 2 >> Euler:/sys/bus/pci # cat /proc/irq/345/smp_affinity_list >> 48 > > node 2 > >> Euler:/sys/bus/pci # cat /proc/irq/369/smp_affinity_list >> 72 > > node 3 > >> Euler:/sys/bus/pci # cat /proc/irq/393/smp_affinity_list >> 24 > > node 1 > > So few more questions. The only difference seems to be IRQ369 > moving from 0 to 3 and having the device affinity to node 2 > makes some sense because node 3 is closer. So far so good. Right, it is what we want. > I still have a large gap to get the whole picture. Namely why those > other IRQs are not using any of the existing CPUs on the node 2. > Could you explain that please? > Oh, my mistake, for the previous instance, I don't list all IRQs and just choose one IRQ from one NUMA node. You can see that the IRQ number is not consistent :-). IRQ from 345 to 368 will be bound to CPU cores which are in NUMA node2 and each IRQ is corresponding to one core. Euler:/sys/bus/pci # cat /proc/irq/346/smp_affinity_list 49 Others are the similar. > Btw. this all should be in the changelog. Ok, I will follow it in future. Thanks, Shaokun >