From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f51.google.com (mail-pa0-f51.google.com [209.85.220.51]) by kanga.kvack.org (Postfix) with ESMTP id 21DC56B0254 for ; Fri, 20 Nov 2015 08:10:56 -0500 (EST) Received: by pabfh17 with SMTP id fh17so120212253pab.0 for ; Fri, 20 Nov 2015 05:10:55 -0800 (PST) Received: from mx2.parallels.com (mx2.parallels.com. [199.115.105.18]) by mx.google.com with ESMTPS id ia2si19600610pbb.85.2015.11.20.05.10.55 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 20 Nov 2015 05:10:55 -0800 (PST) Date: Fri, 20 Nov 2015 16:10:33 +0300 From: Vladimir Davydov Subject: Re: [PATCH 13/14] mm: memcontrol: account socket memory in unified hierarchy memory controller Message-ID: <20151120131033.GF31308@esperanza> References: <1447371693-25143-1-git-send-email-hannes@cmpxchg.org> <1447371693-25143-14-git-send-email-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1447371693-25143-14-git-send-email-hannes@cmpxchg.org> Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: David Miller , Andrew Morton , Tejun Heo , Michal Hocko , netdev@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@fb.com On Thu, Nov 12, 2015 at 06:41:32PM -0500, Johannes Weiner wrote: ... > @@ -5514,16 +5550,43 @@ void sock_release_memcg(struct sock *sk) > */ > bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages) > { > + unsigned int batch = max(CHARGE_BATCH, nr_pages); > struct page_counter *counter; > + bool force = false; > > - if (page_counter_try_charge(&memcg->tcp_mem.memory_allocated, > - nr_pages, &counter)) { > - memcg->tcp_mem.memory_pressure = 0; > +#ifdef CONFIG_MEMCG_KMEM > + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys)) { > + if (page_counter_try_charge(&memcg->tcp_mem.memory_allocated, > + nr_pages, &counter)) { > + memcg->tcp_mem.memory_pressure = 0; > + return true; > + } > + page_counter_charge(&memcg->tcp_mem.memory_allocated, nr_pages); > + memcg->tcp_mem.memory_pressure = 1; > + return false; > + } > +#endif > + if (consume_stock(memcg, nr_pages)) > return true; > +retry: > + if (page_counter_try_charge(&memcg->memory, batch, &counter)) > + goto done; > + > + if (batch > nr_pages) { > + batch = nr_pages; > + goto retry; > } > - page_counter_charge(&memcg->tcp_mem.memory_allocated, nr_pages); > - memcg->tcp_mem.memory_pressure = 1; > - return false; > + > + page_counter_charge(&memcg->memory, batch); > + force = true; > +done: > + css_get_many(&memcg->css, batch); Is there any point to get css reference per each charged page? For kmem it is absolutely necessary, because dangling slabs must block destruction of memcg's kmem caches, which are destroyed on css_free. But for sockets there's no such problem: memcg will be destroyed only after all sockets are destroyed and therefore uncharged (since sock_update_memcg pins css). > + if (batch > nr_pages) > + refill_stock(memcg, batch - nr_pages); > + > + schedule_work(&memcg->socket_work); I think it's suboptimal to schedule the work even if we are below the high threshold. BTW why do we need this work at all? Why is reclaim_high called from task_work not enough? Thanks, Vladimir > + > + return !force; > } > > /** -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org