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=-7.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 A8955C433E0 for ; Fri, 7 Aug 2020 06:21:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 81FFC22CAF for ; Fri, 7 Aug 2020 06:21:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596781265; bh=kcYw7rdPT7nf8C8LR4PoU61MLtrCwNXJJnbBH6t2mX4=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=lJtj0j5GYhoR1p6SqioFIYy35AOMCYZgwj5JEfr1f0FTzy6lGmbDP2e0mA/Bhc6/5 KIG060FdaM9iqUb3VGRR/Xqgf5Eme6N6ZA401Dl/nnSiWm9YgxlM6yyyhevvJ1MvlP yY9qsF8vGFDWQF8gnhsrUNye5NHUYQjIQZ8eE91g= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726038AbgHGGVF (ORCPT ); Fri, 7 Aug 2020 02:21:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:57126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725845AbgHGGVF (ORCPT ); Fri, 7 Aug 2020 02:21:05 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C700C2177B; Fri, 7 Aug 2020 06:21:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1596781264; bh=kcYw7rdPT7nf8C8LR4PoU61MLtrCwNXJJnbBH6t2mX4=; h=Date:From:To:Subject:In-Reply-To:From; b=h2Oibxo1DIBLXBYBgK4jvJ8t64MYQPYJgdQMZAtyk5NwgIagFLwp1YI7u9UUxcOdu uUwaU0fzXfCgjd4ylzIBLXEQPFfKFbuK45u0zRU1yi/CiLd/U7TeRjpjTftlkx6flD 37CcQ9++8jHDqtZduEwH3F3IZ6aqqz6itwdWKInk= Date: Thu, 06 Aug 2020 23:21:03 -0700 From: Andrew Morton To: akpm@linux-foundation.org, cl@linux.com, guro@fb.com, hannes@cmpxchg.org, linux-mm@kvack.org, mhocko@kernel.org, mm-commits@vger.kernel.org, shakeelb@google.com, tj@kernel.org, torvalds@linux-foundation.org, vbabka@suse.cz Subject: [patch 071/163] mm: memcg/slab: deprecate memory.kmem.slabinfo Message-ID: <20200807062103.qn4835jCL%akpm@linux-foundation.org> In-Reply-To: <20200806231643.a2711a608dd0f18bff2caf2b@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: mm-commits-owner@vger.kernel.org Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Roman Gushchin Subject: mm: memcg/slab: deprecate memory.kmem.slabinfo Deprecate memory.kmem.slabinfo. An empty file will be presented if corresponding config options are enabled. The interface is implementation dependent, isn't present in cgroup v2, and is generally useful only for core mm debugging purposes. In other words, it doesn't provide any value for the absolute majority of users. A drgn-based replacement can be found in tools/cgroup/memcg_slabinfo.py. It does support cgroup v1 and v2, mimics memory.kmem.slabinfo output and also allows to get any additional information without a need to recompile the kernel. If a drgn-based solution is too slow for a task, a bpf-based tracing tool can be used, which can easily keep track of all slab allocations belonging to a memory cgroup. Link: http://lkml.kernel.org/r/20200623174037.3951353-11-guro@fb.com Signed-off-by: Roman Gushchin Acked-by: Johannes Weiner Reviewed-by: Vlastimil Babka Reviewed-by: Shakeel Butt Cc: Christoph Lameter Cc: Michal Hocko Cc: Tejun Heo Signed-off-by: Andrew Morton --- mm/memcontrol.c | 3 --- mm/slab_common.c | 31 ++++--------------------------- 2 files changed, 4 insertions(+), 30 deletions(-) --- a/mm/memcontrol.c~mm-memcg-slab-deprecate-memorykmemslabinfo +++ a/mm/memcontrol.c @@ -5114,9 +5114,6 @@ static struct cftype mem_cgroup_legacy_f (defined(CONFIG_SLAB) || defined(CONFIG_SLUB_DEBUG)) { .name = "kmem.slabinfo", - .seq_start = memcg_slab_start, - .seq_next = memcg_slab_next, - .seq_stop = memcg_slab_stop, .seq_show = memcg_slab_show, }, #endif --- a/mm/slab_common.c~mm-memcg-slab-deprecate-memorykmemslabinfo +++ a/mm/slab_common.c @@ -1561,35 +1561,12 @@ void dump_unreclaimable_slab(void) } #if defined(CONFIG_MEMCG_KMEM) -void *memcg_slab_start(struct seq_file *m, loff_t *pos) -{ - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); - - mutex_lock(&slab_mutex); - return seq_list_start(&memcg->kmem_caches, *pos); -} - -void *memcg_slab_next(struct seq_file *m, void *p, loff_t *pos) -{ - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); - - return seq_list_next(p, &memcg->kmem_caches, pos); -} - -void memcg_slab_stop(struct seq_file *m, void *p) -{ - mutex_unlock(&slab_mutex); -} - int memcg_slab_show(struct seq_file *m, void *p) { - struct kmem_cache *s = list_entry(p, struct kmem_cache, - memcg_params.kmem_caches_node); - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); - - if (p == memcg->kmem_caches.next) - print_slabinfo_header(m); - cache_show(s, m); + /* + * Deprecated. + * Please, take a look at tools/cgroup/slabinfo.py . + */ return 0; } #endif _