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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 F1A5BC433E0 for ; Mon, 25 May 2020 15:07:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC8812073B for ; Mon, 25 May 2020 15:07:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391004AbgEYPHY (ORCPT ); Mon, 25 May 2020 11:07:24 -0400 Received: from mx2.suse.de ([195.135.220.15]:50720 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725809AbgEYPHX (ORCPT ); Mon, 25 May 2020 11:07:23 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 4F542B187; Mon, 25 May 2020 15:07:25 +0000 (UTC) Subject: Re: [PATCH v3 08/19] mm: memcg/slab: save obj_cgroup for non-root slab objects To: Roman Gushchin , Andrew Morton Cc: Johannes Weiner , Michal Hocko , linux-mm@kvack.org, kernel-team@fb.com, linux-kernel@vger.kernel.org References: <20200422204708.2176080-1-guro@fb.com> <20200422204708.2176080-9-guro@fb.com> From: Vlastimil Babka Message-ID: <3e02b3c6-2bf5-bddb-d855-83a1a1a54034@suse.cz> Date: Mon, 25 May 2020 17:07:22 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200422204708.2176080-9-guro@fb.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/22/20 10:46 PM, Roman Gushchin wrote: > Store the obj_cgroup pointer in the corresponding place of > page->obj_cgroups for each allocated non-root slab object. > Make sure that each allocated object holds a reference to obj_cgroup. > > Objcg pointer is obtained from the memcg->objcg dereferencing > in memcg_kmem_get_cache() and passed from pre_alloc_hook to > post_alloc_hook. Then in case of successful allocation(s) it's > getting stored in the page->obj_cgroups vector. > > The objcg obtaining part look a bit bulky now, but it will be simplified > by next commits in the series. > > Signed-off-by: Roman Gushchin Reviewed-by: Vlastimil Babka Nit below: > diff --git a/mm/slab.h b/mm/slab.h > index 44def57f050e..525e09e05743 100644 > --- a/mm/slab.h > +++ b/mm/slab.h ... > @@ -636,8 +684,8 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, > s->flags, flags); > } > > - if (memcg_kmem_enabled()) > - memcg_kmem_put_cache(s); > + if (!is_root_cache(s)) > + memcg_slab_post_alloc_hook(s, objcg, size, p); > } > > #ifndef CONFIG_SLOB Keep also the memcg_kmem_enabled() static key check, like elsewhere?