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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 51780C43331 for ; Tue, 24 Mar 2020 01:04:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 089F520722 for ; Tue, 24 Mar 2020 01:04:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="xmc53TGy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 089F520722 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 9A56F6B009D; Mon, 23 Mar 2020 21:04:00 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 956946B009F; Mon, 23 Mar 2020 21:04:00 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 86B386B00A0; Mon, 23 Mar 2020 21:04:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0095.hostedemail.com [216.40.44.95]) by kanga.kvack.org (Postfix) with ESMTP id 6BD716B009D for ; Mon, 23 Mar 2020 21:04:00 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4C0B9187D7D98 for ; Tue, 24 Mar 2020 01:04:00 +0000 (UTC) X-FDA: 76628459040.13.fuel39_7a3c4a62ee950 X-HE-Tag: fuel39_7a3c4a62ee950 X-Filterd-Recvd-Size: 3866 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf43.hostedemail.com (Postfix) with ESMTP for ; Tue, 24 Mar 2020 01:03:59 +0000 (UTC) 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 7E7C820714; Tue, 24 Mar 2020 01:03:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585011838; bh=uGGoqYkk12Dhiif/0LKZN7D/gATzYrywbbLaYZL5UvE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=xmc53TGy1lYg/FgacCVbCE3vN0AYtiGyt42sLMLiBj7UOGuNKqnRYAC005PcKO5pq KZomxlxQuJIATJPd1VGvz4BgtxOCT5gYH7+uuS7w4by1sCZwJ2GDXofQsTSpvk3L24 ApPeF3M1eSjO7/1dOWh3UqUBSgZ96Rt+3MsMGTGA= Date: Mon, 23 Mar 2020 18:03:58 -0700 From: Andrew Morton To: Roman Gushchin Cc: Johannes Weiner , Michal Hocko , , , , Bharata B Rao , Subject: Re: [PATCH] mm: fork: fix kernel_stack memcg stats for various stack implementations Message-Id: <20200323180358.7603217aa9955f298255da4e@linux-foundation.org> In-Reply-To: <20200324004221.GA36662@carbon.dhcp.thefacebook.com> References: <20200303233550.251375-1-guro@fb.com> <20200321164856.be68344b7fac84b759e23727@linux-foundation.org> <20200324004221.GA36662@carbon.dhcp.thefacebook.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, 23 Mar 2020 17:42:21 -0700 Roman Gushchin wrote: > How about this one? I've merged them into one and stripped it a little bit. > > Thanks! > Yes, that looks good. Here's the delta from the previously reviewed version. I think it's valid to retain those acks and revewed-by's. From: Roman Gushchin Subject: mm: fork: fix kernel_stack memcg stats for various stack implementations --- a/include/linux/memcontrol.h~mm-fork-fix-kernel_stack-memcg-stats-for-various-stack-implementations-v2 +++ a/include/linux/memcontrol.h @@ -1432,6 +1432,8 @@ static inline int memcg_cache_id(struct return memcg ? memcg->kmemcg_id : -1; } +struct mem_cgroup *mem_cgroup_from_obj(void *p); + #else static inline int memcg_kmem_charge(struct page *page, gfp_t gfp, int order) @@ -1473,6 +1475,11 @@ static inline void memcg_put_cache_ids(v { } +static inline struct mem_cgroup *mem_cgroup_from_obj(void *p) +{ + return NULL; +} + #endif /* CONFIG_MEMCG_KMEM */ #endif /* _LINUX_MEMCONTROL_H */ --- a/mm/memcontrol.c~mm-fork-fix-kernel_stack-memcg-stats-for-various-stack-implementations-v2 +++ a/mm/memcontrol.c @@ -2672,6 +2672,33 @@ static void commit_charge(struct page *p } #ifdef CONFIG_MEMCG_KMEM +/* + * Returns a pointer to the memory cgroup to which the kernel object is charged. + * + * The caller must ensure the memcg lifetime, e.g. by taking rcu_read_lock(), + * cgroup_mutex, etc. + */ +struct mem_cgroup *mem_cgroup_from_obj(void *p) +{ + struct page *page; + + if (mem_cgroup_disabled()) + return NULL; + + page = virt_to_head_page(p); + + /* + * Slab pages don't have page->mem_cgroup set because corresponding + * kmem caches can be reparented during the lifetime. That's why + * memcg_from_slab_page() should be used instead. + */ + if (PageSlab(page)) + return memcg_from_slab_page(page); + + /* All other pages use page->mem_cgroup */ + return page->mem_cgroup; +} + static int memcg_alloc_cache_id(void) { int id, size; _