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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED 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 1EEB4C10F0B for ; Tue, 2 Apr 2019 21:32:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DBB8B2084B for ; Tue, 2 Apr 2019 21:32:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554240755; bh=YCs9ALT43RrMOyhVj/RVmlUky/kNqSo6pLF4Sn7oRXI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=hL12KJhC2HUJdGtZFIweeqHKcNaIctthWznIosja/ojCuZZukV310OEG06abKI+sO TIkGaYX9CHaekEO9EfJvYpnXpnzNfo35RdHW6dAJZauMcdBrtle84oobM0wBtKQR4V 6pY8+YQEbQ6J/SEDwv5zcKF3HRT6JDrGQSJAvT+4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726588AbfDBVcd (ORCPT ); Tue, 2 Apr 2019 17:32:33 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:47992 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725956AbfDBVcd (ORCPT ); Tue, 2 Apr 2019 17:32:33 -0400 Received: from akpm3.svl.corp.google.com (unknown [104.133.8.65]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id E45E3D88; Tue, 2 Apr 2019 21:32:31 +0000 (UTC) Date: Tue, 2 Apr 2019 14:32:30 -0700 From: Andrew Morton To: Johannes Weiner Cc: Greg Thelen , Roman Gushchin , Michal Hocko , Vladimir Davydov , Tejun Heo , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH v2] writeback: use exact memcg dirty counts Message-Id: <20190402143230.3ea53a7d599b2d78c39b77b0@linux-foundation.org> In-Reply-To: <20190401182044.GA3694@cmpxchg.org> References: <20190329174609.164344-1-gthelen@google.com> <20190401182044.GA3694@cmpxchg.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 1 Apr 2019 14:20:44 -0400 Johannes Weiner wrote: > On Fri, Mar 29, 2019 at 10:46:09AM -0700, Greg Thelen wrote: > > @@ -3907,10 +3923,10 @@ void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, > > struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); > > struct mem_cgroup *parent; > > > > - *pdirty = memcg_page_state(memcg, NR_FILE_DIRTY); > > + *pdirty = memcg_exact_page_state(memcg, NR_FILE_DIRTY); > > > > /* this should eventually include NR_UNSTABLE_NFS */ > > - *pwriteback = memcg_page_state(memcg, NR_WRITEBACK); > > + *pwriteback = memcg_exact_page_state(memcg, NR_WRITEBACK); > > *pfilepages = mem_cgroup_nr_lru_pages(memcg, (1 << LRU_INACTIVE_FILE) | > > (1 << LRU_ACTIVE_FILE)); > > Andrew, > > just a head-up: -mm has that LRU stat cleanup series queued ("mm: > memcontrol: clean up the LRU counts tracking") that changes the > mem_cgroup_nr_lru_pages() call here to two memcg_page_state(). > > I'm assuming Greg's fix here will get merged before the cleanup. When > it gets picked up, it'll conflict with "mm: memcontrol: push down > mem_cgroup_nr_lru_pages()". > > "mm: memcontrol: push down mem_cgroup_nr_lru_pages()" will need to be > changed to use memcg_exact_page_state() calls instead of the plain > memcg_page_state() for *pfilepages. > Thanks. Like this? void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages, unsigned long *pheadroom, unsigned long *pdirty, unsigned long *pwriteback) { struct mem_cgroup *memcg = mem_cgroup_from_css(wb->memcg_css); struct mem_cgroup *parent; *pdirty = memcg_exact_page_state(memcg, NR_FILE_DIRTY); /* this should eventually include NR_UNSTABLE_NFS */ *pwriteback = memcg_exact_page_state(memcg, NR_WRITEBACK); *pfilepages = memcg_exact_page_state(memcg, NR_INACTIVE_FILE) + memcg_exact_page_state(memcg, NR_ACTIVE_FILE); *pheadroom = PAGE_COUNTER_MAX; while ((parent = parent_mem_cgroup(memcg))) { unsigned long ceiling = min(memcg->memory.max, memcg->high); unsigned long used = page_counter_read(&memcg->memory); *pheadroom = min(*pheadroom, ceiling - min(ceiling, used)); memcg = parent; } }