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=-14.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1C5EAC07E9B for ; Fri, 9 Jul 2021 14:48:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F30E4613BD for ; Fri, 9 Jul 2021 14:48:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232248AbhGIOvg (ORCPT ); Fri, 9 Jul 2021 10:51:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229561AbhGIOvf (ORCPT ); Fri, 9 Jul 2021 10:51:35 -0400 Received: from mail-qt1-x82f.google.com (mail-qt1-x82f.google.com [IPv6:2607:f8b0:4864:20::82f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 66FEAC0613DD for ; Fri, 9 Jul 2021 07:48:51 -0700 (PDT) Received: by mail-qt1-x82f.google.com with SMTP id v18so1097035qtk.5 for ; Fri, 09 Jul 2021 07:48:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cmpxchg-org.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=Zc2BPQuzaGpps9hYR6A1SS6spRlObwvCzaY7uIl0fFs=; b=JjjnbfYvxPo1NWSBJyvtgC3bk+XjiBXa9XnURKljN5acQnzH15vHkDQMcFUrMK1kKy dllvEWiXreEpZ2IYRdzBgVDviwe/+oDhuJ+32k7xARC6sIYWxqYM47UBp/Jr2KMNe/im Yv1AaH5yzrL2BdSCcFsOcnLsrzO9jBE5in/utMROdxyYfh83hIDL0edY5lWunZJz4qRL jNzVXVUCxw6Wkf51faXzwe6+bYtOPb6hmCIqBp5dsq1c+zYiFrRDb72JlDhrA/BWwgSz obYUN0vGYbcCmC9EWi6WCsqUSZdvbUh5wwq6Th1zP1Jr74QYDo0ogJBNdI143IfDTXXH LUCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Zc2BPQuzaGpps9hYR6A1SS6spRlObwvCzaY7uIl0fFs=; b=SS7AWET55aYkxJWzmsow8nL7znKIIc3R49b08U7cWj2lQ6ZRF0k8Xzg1TadniP84XV VgXFzCVR+q7OeNfcqMD0i1RuzbSBVG2S0sHVpR1u2LxORkCEd1sp7/idBt/fclFSAi5o KzjOidqEonMhobzLHiWI1f64qD6QkvK34cUIxwhPyPnPepEe/FdrWR0FwvMsnyNk0Wb7 hZoTl9lGq5cVV60akNvZEO1DVf6ZM6mgcEuYyEd5bK15JLJZt8UFwAweus0oaaw0dsT7 MgP/W61Y6Fpb2xMkvsxCR73cE9RYZ9bdR8kSkRTO8u0AWoAbgwoyoS577Bl4HmAEEbQT mkVQ== X-Gm-Message-State: AOAM532dmrcAEGWmMfjD2QCnqd4iRQ8efLB8Xc5QW1p9Yq8GRn/VWhLh 7X/8e5qe6yjMUBga85GgDU541w== X-Google-Smtp-Source: ABdhPJymN1G1/IcEEKsYsC76uVcFFA+vVSUTNwGP91lvr0dxcWNiE3iRXktWTxmOtZ7K1vS9aeSNmQ== X-Received: by 2002:a05:622a:449:: with SMTP id o9mr34293601qtx.272.1625842130626; Fri, 09 Jul 2021 07:48:50 -0700 (PDT) Received: from localhost ([2620:10d:c091:480::1:8649]) by smtp.gmail.com with ESMTPSA id l5sm2573791qkb.62.2021.07.09.07.48.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 09 Jul 2021 07:48:49 -0700 (PDT) Date: Fri, 9 Jul 2021 10:48:48 -0400 From: Johannes Weiner To: Suren Baghdasaryan Cc: tj@kernel.org, mhocko@kernel.org, vdavydov.dev@gmail.com, akpm@linux-foundation.org, shakeelb@google.com, guro@fb.com, songmuchun@bytedance.com, shy828301@gmail.com, alexs@kernel.org, alexander.h.duyck@linux.intel.com, richard.weiyang@gmail.com, vbabka@suse.cz, axboe@kernel.dk, iamjoonsoo.kim@lge.com, david@redhat.com, willy@infradead.org, apopple@nvidia.com, minchan@kernel.org, linmiaohe@huawei.com, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kernel-team@android.com Subject: Re: [PATCH 2/3] mm, memcg: inline mem_cgroup_{charge/uncharge} to improve disabled memcg config Message-ID: References: <20210709000509.2618345-1-surenb@google.com> <20210709000509.2618345-3-surenb@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210709000509.2618345-3-surenb@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 08, 2021 at 05:05:08PM -0700, Suren Baghdasaryan wrote: > Inline mem_cgroup_{charge/uncharge} and mem_cgroup_uncharge_list functions > functions to perform mem_cgroup_disabled static key check inline before > calling the main body of the function. This minimizes the memcg overhead > in the pagefault and exit_mmap paths when memcgs are disabled using > cgroup_disable=memory command-line option. > This change results in ~0.4% overhead reduction when running PFT test > comparing {CONFIG_MEMCG=n} against {CONFIG_MEMCG=y, cgroup_disable=memory} > configurationon on an 8-core ARM64 Android device. > > Signed-off-by: Suren Baghdasaryan Sounds reasonable to me as well. One comment: > @@ -693,13 +693,59 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg) > page_counter_read(&memcg->memory); > } > > -int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask); > +struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm); > + > +int __mem_cgroup_charge(struct page *page, struct mem_cgroup *memcg, > + gfp_t gfp); > +/** > + * mem_cgroup_charge - charge a newly allocated page to a cgroup > + * @page: page to charge > + * @mm: mm context of the victim > + * @gfp_mask: reclaim mode > + * > + * Try to charge @page to the memcg that @mm belongs to, reclaiming > + * pages according to @gfp_mask if necessary. if @mm is NULL, try to > + * charge to the active memcg. > + * > + * Do not use this for pages allocated for swapin. > + * > + * Returns 0 on success. Otherwise, an error code is returned. > + */ > +static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm, > + gfp_t gfp_mask) > +{ > + struct mem_cgroup *memcg; > + int ret; > + > + if (mem_cgroup_disabled()) > + return 0; > + > + memcg = get_mem_cgroup_from_mm(mm); > + ret = __mem_cgroup_charge(page, memcg, gfp_mask); > + css_put(&memcg->css); > + > + return ret; Why not do int __mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask); static inline int mem_cgroup_charge(struct page *page, struct mm_struct *mm, gfp_t gfp_mask) { if (mem_cgroup_disabled()) return 0; return __mem_cgroup_charge(page, memcg, gfp_mask); } like in the other cases as well? That would avoid inlining two separate function calls into all the callsites... There is an (internal) __mem_cgroup_charge() already, but you can rename it charge_memcg().