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=-9.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 E894FC282C0 for ; Fri, 25 Jan 2019 07:24:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3555218EA for ; Fri, 25 Jan 2019 07:24:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548401075; bh=N9XMA7a3bQoV94ELIDbjuV0/37IqFrqBcMEl87YKkcM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=d3ElR1bNFNNJs44ZCsMAhr6RW+kDPc2kLAcQeuncwA8Xl55G4nj2d1Nw0DE9uWhdi MDPSu2lB++Hatwl5h6JLU3xShkAtZzkKOKPTd8pPBoUAlL8hWRRJdyBT1+BqZ5og4m wyDpzk2BXnSMgZx6mm4+kDETuYNu9nD/tlEbH4nc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728395AbfAYHYe (ORCPT ); Fri, 25 Jan 2019 02:24:34 -0500 Received: from mx2.suse.de ([195.135.220.15]:40546 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726520AbfAYHYd (ORCPT ); Fri, 25 Jan 2019 02:24:33 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 73196AEA3; Fri, 25 Jan 2019 07:24:31 +0000 (UTC) Date: Fri, 25 Jan 2019 08:24:29 +0100 From: Michal Hocko To: Chris Down Cc: Andrew Morton , Johannes Weiner , Tejun Heo , Roman Gushchin , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kernel-team@fb.com Subject: Re: [PATCH 2/2] mm: Extract memcg maxable seq_file logic to seq_show_memcg_tunable Message-ID: <20190125072429.GA3560@dhcp22.suse.cz> References: <20190124194100.GA31425@chrisdown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190124194100.GA31425@chrisdown.name> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 24-01-19 14:41:00, Chris Down wrote: > memcg has a significant number of files exposed to kernfs where their > value is either exposed directly or is "max" in the case of > PAGE_COUNTER_MAX. > > This patch makes this generic by providing a single function to do this > work. In combination with the previous patch adding mem_cgroup_from_seq, > this makes all of the seq_show feeder functions significantly more > simple. Yeah this is what I've had in mind when mentioning a helper in the previous version of the patch. I like this more even though the resulting savings are not that large. > Signed-off-by: Chris Down > Cc: Andrew Morton > Cc: Johannes Weiner > Cc: Tejun Heo > Cc: Roman Gushchin > Cc: linux-kernel@vger.kernel.org > Cc: cgroups@vger.kernel.org > Cc: linux-mm@kvack.org > Cc: kernel-team@fb.com Acked-by: Michal Hocko > --- > mm/memcontrol.c | 64 +++++++++++++++---------------------------------- > 1 file changed, 19 insertions(+), 45 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 98aad31f5226..81b6f752471a 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -5375,6 +5375,16 @@ static void mem_cgroup_bind(struct cgroup_subsys_state *root_css) > root_mem_cgroup->use_hierarchy = false; > } > > +static int seq_puts_memcg_tunable(struct seq_file *m, unsigned long value) > +{ > + if (value == PAGE_COUNTER_MAX) > + seq_puts(m, "max\n"); > + else > + seq_printf(m, "%llu\n", (u64)value * PAGE_SIZE); > + > + return 0; > +} > + > static u64 memory_current_read(struct cgroup_subsys_state *css, > struct cftype *cft) > { > @@ -5385,15 +5395,8 @@ static u64 memory_current_read(struct cgroup_subsys_state *css, > > static int memory_min_show(struct seq_file *m, void *v) > { > - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); > - unsigned long min = READ_ONCE(memcg->memory.min); > - > - if (min == PAGE_COUNTER_MAX) > - seq_puts(m, "max\n"); > - else > - seq_printf(m, "%llu\n", (u64)min * PAGE_SIZE); > - > - return 0; > + return seq_puts_memcg_tunable(m, > + READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); > } > > static ssize_t memory_min_write(struct kernfs_open_file *of, > @@ -5415,15 +5418,8 @@ static ssize_t memory_min_write(struct kernfs_open_file *of, > > static int memory_low_show(struct seq_file *m, void *v) > { > - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); > - unsigned long low = READ_ONCE(memcg->memory.low); > - > - if (low == PAGE_COUNTER_MAX) > - seq_puts(m, "max\n"); > - else > - seq_printf(m, "%llu\n", (u64)low * PAGE_SIZE); > - > - return 0; > + return seq_puts_memcg_tunable(m, > + READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); > } > > static ssize_t memory_low_write(struct kernfs_open_file *of, > @@ -5445,15 +5441,7 @@ static ssize_t memory_low_write(struct kernfs_open_file *of, > > static int memory_high_show(struct seq_file *m, void *v) > { > - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); > - unsigned long high = READ_ONCE(memcg->high); > - > - if (high == PAGE_COUNTER_MAX) > - seq_puts(m, "max\n"); > - else > - seq_printf(m, "%llu\n", (u64)high * PAGE_SIZE); > - > - return 0; > + return seq_puts_memcg_tunable(m, READ_ONCE(mem_cgroup_from_seq(m)->high)); > } > > static ssize_t memory_high_write(struct kernfs_open_file *of, > @@ -5482,15 +5470,8 @@ static ssize_t memory_high_write(struct kernfs_open_file *of, > > static int memory_max_show(struct seq_file *m, void *v) > { > - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); > - unsigned long max = READ_ONCE(memcg->memory.max); > - > - if (max == PAGE_COUNTER_MAX) > - seq_puts(m, "max\n"); > - else > - seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE); > - > - return 0; > + return seq_puts_memcg_tunable(m, > + READ_ONCE(mem_cgroup_from_seq(m)->memory.max)); > } > > static ssize_t memory_max_write(struct kernfs_open_file *of, > @@ -6622,15 +6603,8 @@ static u64 swap_current_read(struct cgroup_subsys_state *css, > > static int swap_max_show(struct seq_file *m, void *v) > { > - struct mem_cgroup *memcg = mem_cgroup_from_seq(m); > - unsigned long max = READ_ONCE(memcg->swap.max); > - > - if (max == PAGE_COUNTER_MAX) > - seq_puts(m, "max\n"); > - else > - seq_printf(m, "%llu\n", (u64)max * PAGE_SIZE); > - > - return 0; > + return seq_puts_memcg_tunable(m, > + READ_ONCE(mem_cgroup_from_seq(m)->swap.max)); > } > > static ssize_t swap_max_write(struct kernfs_open_file *of, > -- > 2.20.1 -- Michal Hocko SUSE Labs