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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 D9704C433DB for ; Wed, 27 Jan 2021 14:02:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A1EA420799 for ; Wed, 27 Jan 2021 14:02:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232657AbhA0OBv (ORCPT ); Wed, 27 Jan 2021 09:01:51 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:54766 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232180AbhA0OAu (ORCPT ); Wed, 27 Jan 2021 09:00:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1611755960; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=84QZLW2MmSKQhGMceaFRzTS4p8xthVnRtABZqSeleds=; b=IsX79c/YzmEtBfaMwaEUcBkvHUkSXsfHfu+roUsRQXEMSN3SMuz6UORXQ78FCsTwMj+CcH Kannd6j34OD2N6FeCgU/Vf2LxWesv/OXTCTc1hyGSqVnI9m92cWbMzSJLCwjyKW/GGfJIR HzG0QIX4k61ie2sQHGviDbw1RaapJnc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-394-5xc57rt9NrCl0H2D8DACtg-1; Wed, 27 Jan 2021 08:59:18 -0500 X-MC-Unique: 5xc57rt9NrCl0H2D8DACtg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6E8B5107ACE4; Wed, 27 Jan 2021 13:59:16 +0000 (UTC) Received: from [10.36.114.237] (ovpn-114-237.ams2.redhat.com [10.36.114.237]) by smtp.corp.redhat.com (Postfix) with ESMTP id 044A06F451; Wed, 27 Jan 2021 13:59:12 +0000 (UTC) Subject: Re: [PATCH] mm, slub: remove slub_memcg_sysfs boot param and CONFIG_SLUB_MEMCG_SYSFS_ON To: Vlastimil Babka , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Roman Gushchin References: <20210127124745.7928-1-vbabka@suse.cz> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <8f989256-9e43-1747-4de5-fa46db0d7f7e@redhat.com> Date: Wed, 27 Jan 2021 14:59:12 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: <20210127124745.7928-1-vbabka@suse.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 27.01.21 13:47, Vlastimil Babka wrote: > The boot param and config determine the value of memcg_sysfs_enabled, which is > unused since commit 10befea91b61 ("mm: memcg/slab: use a single set of > kmem_caches for all allocations") as there are no per-memcg kmem caches > anymore. > > Signed-off-by: Vlastimil Babka > --- > Documentation/admin-guide/kernel-parameters.txt | 8 -------- > init/Kconfig | 14 -------------- > mm/slub.c | 16 ---------------- > 3 files changed, 38 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index f4497faef266..7dc351da0005 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -4892,14 +4892,6 @@ > last alloc / free. For more information see > Documentation/vm/slub.rst. > > - slub_memcg_sysfs= [MM, SLUB] > - Determines whether to enable sysfs directories for > - memory cgroup sub-caches. 1 to enable, 0 to disable. > - The default is determined by CONFIG_SLUB_MEMCG_SYSFS_ON. > - Enabling this can lead to a very high number of debug > - directories and files being created under > - /sys/kernel/slub. > - > slub_max_order= [MM, SLUB] > Determines the maximum allowed order for slabs. > A high setting may cause OOMs due to memory > diff --git a/init/Kconfig b/init/Kconfig > index e4e2932da237..af454a51f3c5 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -1851,20 +1851,6 @@ config SLUB_DEBUG > SLUB sysfs support. /sys/slab will not exist and there will be > no support for cache validation etc. > > -config SLUB_MEMCG_SYSFS_ON > - default n > - bool "Enable memcg SLUB sysfs support by default" if EXPERT > - depends on SLUB && SYSFS && MEMCG > - help > - SLUB creates a directory under /sys/kernel/slab for each > - allocation cache to host info and debug files. If memory > - cgroup is enabled, each cache can have per memory cgroup > - caches. SLUB can create the same sysfs directories for these > - caches under /sys/kernel/slab/CACHE/cgroup but it can lead > - to a very high number of debug files being created. This is > - controlled by slub_memcg_sysfs boot parameter and this > - config option determines the parameter's default value. > - > config COMPAT_BRK > bool "Disable heap randomization" > default y > diff --git a/mm/slub.c b/mm/slub.c > index 1b5148747c64..88782727412c 100644 > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -5040,22 +5040,6 @@ enum slab_stat_type { > #define SO_OBJECTS (1 << SL_OBJECTS) > #define SO_TOTAL (1 << SL_TOTAL) > > -#ifdef CONFIG_MEMCG > -static bool memcg_sysfs_enabled = IS_ENABLED(CONFIG_SLUB_MEMCG_SYSFS_ON); > - > -static int __init setup_slub_memcg_sysfs(char *str) > -{ > - int v; > - > - if (get_option(&str, &v) > 0) > - memcg_sysfs_enabled = v; > - > - return 1; > -} > - > -__setup("slub_memcg_sysfs=", setup_slub_memcg_sysfs); > -#endif > - > static ssize_t show_slab_objects(struct kmem_cache *s, > char *buf, unsigned long flags) > { > Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb