From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752988AbbAQPVb (ORCPT ); Sat, 17 Jan 2015 10:21:31 -0500 Received: from gum.cmpxchg.org ([85.214.110.215]:57669 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751232AbbAQPVa (ORCPT ); Sat, 17 Jan 2015 10:21:30 -0500 From: Johannes Weiner To: Andrew Morton Cc: Michal Hocko , Vladimir Davydov , Greg Thelen , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [patch] mm: memcontrol: default hierarchy interface for memory fix - high reclaim Date: Sat, 17 Jan 2015 10:21:19 -0500 Message-Id: <1421508079-29293-1-git-send-email-hannes@cmpxchg.org> X-Mailer: git-send-email 2.2.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org High limit reclaim can currently overscan in proportion to how many charges are happening concurrently. Tone it down such that charges don't target the entire high-boundary excess, but instead only the pages they charged themselves when excess is detected. Reported-by: Michal Hocko Signed-off-by: Johannes Weiner --- mm/memcontrol.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 323a01fa1833..7adccee9fecb 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2348,19 +2348,13 @@ done_restock: refill_stock(memcg, batch - nr_pages); /* * If the hierarchy is above the normal consumption range, - * make the charging task trim the excess. + * make the charging task trim their excess contribution. */ do { - unsigned long nr_pages = page_counter_read(&memcg->memory); - unsigned long high = ACCESS_ONCE(memcg->high); - - if (nr_pages > high) { - mem_cgroup_events(memcg, MEMCG_HIGH, 1); - - try_to_free_mem_cgroup_pages(memcg, nr_pages - high, - gfp_mask, true); - } - + if (page_counter_read(&memcg->memory) <= memcg->high) + continue; + mem_cgroup_events(memcg, MEMCG_HIGH, 1); + try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, true); } while ((memcg = parent_mem_cgroup(memcg))); done: return ret; -- 2.2.0