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=-7.1 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 autolearn=unavailable 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 6A2B0C433DF for ; Mon, 22 Jun 2020 01:48:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 442D524746 for ; Mon, 22 Jun 2020 01:48:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="A5Ut+EvX" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726778AbgFVBsI (ORCPT ); Sun, 21 Jun 2020 21:48:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726456AbgFVBsH (ORCPT ); Sun, 21 Jun 2020 21:48:07 -0400 Received: from mail-oi1-x243.google.com (mail-oi1-x243.google.com [IPv6:2607:f8b0:4864:20::243]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9620EC061794 for ; Sun, 21 Jun 2020 18:48:06 -0700 (PDT) Received: by mail-oi1-x243.google.com with SMTP id 25so14195484oiy.13 for ; Sun, 21 Jun 2020 18:48:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=Ze28Eq/j1gsI361qz29/4oK9sda0rS5bu0lcqoefJK4=; b=A5Ut+EvXuufgcQV6Yjo2m8t0r0g8kB0waG/TFfDqrTSTv0G7kNRFA3sOFdObE4QzYS OCmAYmlZcm4mE4BqpfYt05/0ELYBoiZG/zye5xTLTmNy4V67dduiYz7FJFag91H3vLMW Bn3M+1C2XBGEWArEuyp+tnk1a48bmR091Nkidb+tzp2/V7xfDbG4mfpZg1lZoBXpjeU1 ciADZt5d5x3NCseEZawRH7uO1H+uPb0PQb7Azj3y3Cq9cQPmLfOezZ+BoSsEFbvFbLvX sk4IVUEsKLFdf6UiZHUO/lx1MgHdexBPjx5p1SCcT12j6wG6rhLarsRTHA1KcCNZFXPL Ngkg== 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=Ze28Eq/j1gsI361qz29/4oK9sda0rS5bu0lcqoefJK4=; b=f41IuVEKjZMp+yOn3qhYWj8jC4cgU7OG0kVuKODpMA69tsJrcg98AHMrQBYn002RqE aBRoIMGpITDubfhMWb01yxFKQa7fMnyUt25aXWcrl1z6bwi9+shdpaEmKXkwSki+xgup iqXxrBubO194uxoFOIBo1t2J6zE0JTH/olg4o9bQBpc6B3K6ekRq+sPTp5J/RYJX0sYu 5bp5BXynO4bD5jBi8PVRE4XcgTcvdxGwq9mRogLlKJoqRD74FR3dB93vH78AMcvsM/34 0sfRBQwGbSMcXXqftvDAqQAnNZjMFwbCuMZ3iMvE2dabz7abq4le/54OK6+6g+LW0uLN uG1Q== X-Gm-Message-State: AOAM531TVOa5ifC2qDcaBciGpg4ocAcjm2Qqa/BnY+AWIWJjKJXqniG4 vW5vbbJpwpzESZYDiaaowYAuSW5f X-Google-Smtp-Source: ABdhPJxLDIPe1X86eTVAUkaTFcV/WnaVfBnbfgqsmCj5SBDAo5s0P38sMrWCTq/08adc+EKbFt3XSg== X-Received: by 2002:a54:4406:: with SMTP id k6mr11236087oiw.60.1592790485427; Sun, 21 Jun 2020 18:48:05 -0700 (PDT) Received: from ubuntu-n2-xlarge-x86 ([2604:1380:4111:8b00::3]) by smtp.gmail.com with ESMTPSA id s15sm2961118oic.54.2020.06.21.18.48.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 21 Jun 2020 18:48:04 -0700 (PDT) Date: Sun, 21 Jun 2020 18:48:03 -0700 From: Nathan Chancellor To: Roman Gushchin Cc: Andrew Morton , Dennis Zhou , Tejun Heo , Christoph Lameter , Johannes Weiner , Michal Hocko , Shakeel Butt , linux-mm@kvack.org, kernel-team@fb.com, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com Subject: Re: [PATCH v2 3/5] mm: memcg/percpu: per-memcg percpu memory statistics Message-ID: <20200622014803.GA2916179@ubuntu-n2-xlarge-x86> References: <20200608230819.832349-1-guro@fb.com> <20200608230819.832349-4-guro@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200608230819.832349-4-guro@fb.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 08, 2020 at 04:08:17PM -0700, Roman Gushchin wrote: > Percpu memory can represent a noticeable chunk of the total > memory consumption, especially on big machines with many CPUs. > Let's track percpu memory usage for each memcg and display > it in memory.stat. > > A percpu allocation is usually scattered over multiple pages > (and nodes), and can be significantly smaller than a page. > So let's add a byte-sized counter on the memcg level: > MEMCG_PERCPU_B. Byte-sized vmstat infra created for slabs > can be perfectly reused for percpu case. > > Signed-off-by: Roman Gushchin > Acked-by: Dennis Zhou > --- > Documentation/admin-guide/cgroup-v2.rst | 4 ++++ > include/linux/memcontrol.h | 8 ++++++++ > mm/memcontrol.c | 4 +++- > mm/percpu.c | 10 ++++++++++ > 4 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst > index ce3e05e41724..7c1e784239bf 100644 > --- a/Documentation/admin-guide/cgroup-v2.rst > +++ b/Documentation/admin-guide/cgroup-v2.rst > @@ -1274,6 +1274,10 @@ PAGE_SIZE multiple when read back. > Amount of memory used for storing in-kernel data > structures. > > + percpu > + Amount of memory used for storing per-cpu kernel > + data structures. > + > sock > Amount of memory used in network transmission buffers > > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h > index eede46c43573..7ed3af71a6fb 100644 > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -32,11 +32,19 @@ struct kmem_cache; > enum memcg_stat_item { > MEMCG_SWAP = NR_VM_NODE_STAT_ITEMS, > MEMCG_SOCK, > + MEMCG_PERCPU_B, > /* XXX: why are these zone and not node counters? */ > MEMCG_KERNEL_STACK_KB, > MEMCG_NR_STAT, > }; > > +static __always_inline bool memcg_stat_item_in_bytes(enum memcg_stat_item item) > +{ > + if (item == MEMCG_PERCPU_B) > + return true; > + return vmstat_item_in_bytes(item); This patch is now in -next and this line causes a warning from clang, which shows up in every translation unit that includes this header, which is a lot: include/linux/memcontrol.h:45:30: warning: implicit conversion from enumeration type 'enum memcg_stat_item' to different enumeration type 'enum node_stat_item' [-Wenum-conversion] return vmstat_item_in_bytes(item); ~~~~~~~~~~~~~~~~~~~~ ^~~~ 1 warning generated. I assume this conversion is intentional; if so, it seems like expecting a specific enum is misleading. Perhaps this should be applied on top? Cheers, Nathan diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 2499f78cf32d..bddeb4ce7a4f 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -38,7 +38,7 @@ enum memcg_stat_item { MEMCG_NR_STAT, }; -static __always_inline bool memcg_stat_item_in_bytes(enum memcg_stat_item item) +static __always_inline bool memcg_stat_item_in_bytes(int item) { if (item == MEMCG_PERCPU_B) return true; diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 084ee1c17160..52d7961a24f0 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -211,7 +211,7 @@ enum node_stat_item { * measured in pages). This defines the API part, the internal representation * might be different. */ -static __always_inline bool vmstat_item_in_bytes(enum node_stat_item item) +static __always_inline bool vmstat_item_in_bytes(int item) { /* * Global and per-node slab counters track slab pages.