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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 9AC68C3F2D1 for ; Wed, 4 Mar 2020 02:21:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 607FA2146E for ; Wed, 4 Mar 2020 02:21:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TZwFCinu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387542AbgCDCVX (ORCPT ); Tue, 3 Mar 2020 21:21:23 -0500 Received: from mail-pg1-f201.google.com ([209.85.215.201]:37806 "EHLO mail-pg1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387400AbgCDCVW (ORCPT ); Tue, 3 Mar 2020 21:21:22 -0500 Received: by mail-pg1-f201.google.com with SMTP id q29so334870pgk.4 for ; Tue, 03 Mar 2020 18:21:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=+xah7E//6pVRKdaZXmFI1T6nfuFUo9iVXUkHyM4jmQo=; b=TZwFCinuj11xZdNvspmekDI0x79O/EQihOSSmxMSVxtrpfdyMQkBRLLvD95CEFCzpX LLJPxfEnWDkieQxh7QIxWxbToGfC+DMpLfbgM4udxeAy8K5yQHCP1k4fD6xZVxK51r2m uCNK6OZd3TSqEautzdRJCITCLeqff8iyKCZFyG01AxM0dPjwy0pwIyjdDBheYzwyIB3M b21oYiHUF7a9PAjanaiCpWH4aFMeYD4jjLh872JSJ0BGqqi1PHtAr+BikLaErcxfrWv+ U1c2HZsQTLpu4Y39JF9rjKug9K9KM/Wd6WgOrSRcCsD9Dn0Qs8DAYqL4Shs4nsmMLQXh vgFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=+xah7E//6pVRKdaZXmFI1T6nfuFUo9iVXUkHyM4jmQo=; b=uIb/upDjHQdjyFv23hVMPwSkhwa9PLyN2uh6F22dByKLJ3wp+m2fmNrdFdTkPG/Om4 Id9x2zZAvx3RSG0Xvt1Hch9HSbcUIQRs4L0ZSdwrnao7PNM9vN0xrPM4vkHuJKajZWCf 5JV7N3JSLYVjvv2k1pjXKz4lQYiE8EneEP+hQv8Fh0OdRBTXd1wv6+eyLH3TelFZkaIK M6sTFuP8VSwd5OBDiSfZgUa+JS/BY9t9m37GvfbO57rI5nT2Eov2Y5pKFo1qU1f/sEiT 4tZWaFX+hw5IYOgVPZBO1Tq8e3NpWgVnYkBgMB6z8WZ3tT5C+unT39amQhUDfEPyglg2 9W3w== X-Gm-Message-State: ANhLgQ03EBG12rq3XamjWZrwnk5L/s+3nchD8B+BKSjXCDpR9tNd7UPy jxXk9a9Jo6DxG+Oi+uYt7YMrS6PF7y0HDw== X-Google-Smtp-Source: ADFU+vu8OtgDgAEEtoJCrBqXEjW+PtdPObK6IdK9ihXt3F3QrY5fhSy5oyuvRqAnRLJJE4WOR6O7U3lAP9UJDA== X-Received: by 2002:a63:731c:: with SMTP id o28mr418425pgc.139.1583288481764; Tue, 03 Mar 2020 18:21:21 -0800 (PST) Date: Tue, 3 Mar 2020 18:20:58 -0800 Message-Id: <20200304022058.248270-1-shakeelb@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog Subject: [PATCH] memcg: optimize memory.numa_stat like memory.stat From: Shakeel Butt To: Johannes Weiner , Roman Gushchin Cc: Michal Hocko , Andrew Morton , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Shakeel Butt Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently reading memory.numa_stat traverses the underlying memcg tree multiple times to accumulate the stats to present the hierarchical view of the memcg tree. However the kernel already maintains the hierarchical view of the stats and use it in memory.stat. Just use the same mechanism in memory.numa_stat as well. I ran a simple benchmark which reads root_mem_cgroup's memory.numa_stat file in the presense of 10000 memcgs. The results are: Without the patch: $ time cat /dev/cgroup/memory/memory.numa_stat > /dev/null real 0m0.700s user 0m0.001s sys 0m0.697s With the patch: $ time cat /dev/cgroup/memory/memory.numa_stat > /dev/null real 0m0.001s user 0m0.001s sys 0m0.000s Signed-off-by: Shakeel Butt --- mm/memcontrol.c | 52 +++++++++++++++++++++++++------------------------ 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 63bb6a2aab81..d5485fa8a345 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3614,32 +3614,40 @@ static int mem_cgroup_move_charge_write(struct cgroup_subsys_state *css, #define LRU_ALL ((1 << NR_LRU_LISTS) - 1) static unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg, - int nid, unsigned int lru_mask) + int nid, unsigned int lru_mask, bool tree) { struct lruvec *lruvec = mem_cgroup_lruvec(memcg, NODE_DATA(nid)); unsigned long nr = 0; enum lru_list lru; + unsigned long (*page_state)(struct lruvec *lruvec, + enum node_stat_item idx); VM_BUG_ON((unsigned)nid >= nr_node_ids); + page_state = tree ? lruvec_page_state : lruvec_page_state_local; + for_each_lru(lru) { if (!(BIT(lru) & lru_mask)) continue; - nr += lruvec_page_state_local(lruvec, NR_LRU_BASE + lru); + nr += page_state(lruvec, NR_LRU_BASE + lru); } return nr; } static unsigned long mem_cgroup_nr_lru_pages(struct mem_cgroup *memcg, - unsigned int lru_mask) + unsigned int lru_mask, + bool tree) { unsigned long nr = 0; enum lru_list lru; + unsigned long (*page_state)(struct mem_cgroup *memcg, int idx); + + page_state = tree ? memcg_page_state : memcg_page_state_local; for_each_lru(lru) { if (!(BIT(lru) & lru_mask)) continue; - nr += memcg_page_state_local(memcg, NR_LRU_BASE + lru); + nr += page_state(memcg, NR_LRU_BASE + lru); } return nr; } @@ -3659,34 +3667,28 @@ static int memcg_numa_stat_show(struct seq_file *m, void *v) }; const struct numa_stat *stat; int nid; - unsigned long nr; struct mem_cgroup *memcg = mem_cgroup_from_seq(m); for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { - nr = mem_cgroup_nr_lru_pages(memcg, stat->lru_mask); - seq_printf(m, "%s=%lu", stat->name, nr); - for_each_node_state(nid, N_MEMORY) { - nr = mem_cgroup_node_nr_lru_pages(memcg, nid, - stat->lru_mask); - seq_printf(m, " N%d=%lu", nid, nr); - } + seq_printf(m, "%s=%lu", stat->name, + mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, + false)); + for_each_node_state(nid, N_MEMORY) + seq_printf(m, " N%d=%lu", nid, + mem_cgroup_node_nr_lru_pages(memcg, nid, + stat->lru_mask, false)); seq_putc(m, '\n'); } for (stat = stats; stat < stats + ARRAY_SIZE(stats); stat++) { - struct mem_cgroup *iter; - - nr = 0; - for_each_mem_cgroup_tree(iter, memcg) - nr += mem_cgroup_nr_lru_pages(iter, stat->lru_mask); - seq_printf(m, "hierarchical_%s=%lu", stat->name, nr); - for_each_node_state(nid, N_MEMORY) { - nr = 0; - for_each_mem_cgroup_tree(iter, memcg) - nr += mem_cgroup_node_nr_lru_pages( - iter, nid, stat->lru_mask); - seq_printf(m, " N%d=%lu", nid, nr); - } + + seq_printf(m, "hierarchical_%s=%lu", stat->name, + mem_cgroup_nr_lru_pages(memcg, stat->lru_mask, + true)); + for_each_node_state(nid, N_MEMORY) + seq_printf(m, " N%d=%lu", nid, + mem_cgroup_node_nr_lru_pages(memcg, nid, + stat->lru_mask, true)); seq_putc(m, '\n'); } -- 2.25.0.265.gbab2e86ba0-goog