From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f47.google.com (mail-wm0-f47.google.com [74.125.82.47]) by kanga.kvack.org (Postfix) with ESMTP id D76F06B0263 for ; Sat, 14 Nov 2015 10:15:31 -0500 (EST) Received: by wmec201 with SMTP id c201so119828549wme.0 for ; Sat, 14 Nov 2015 07:15:31 -0800 (PST) Received: from gum.cmpxchg.org (gum.cmpxchg.org. [85.214.110.215]) by mx.google.com with ESMTPS id c12si13396688wmh.122.2015.11.14.07.15.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 14 Nov 2015 07:15:30 -0800 (PST) Date: Sat, 14 Nov 2015 10:15:18 -0500 From: Johannes Weiner Subject: Re: [PATCH 03/14] net: tcp_memcontrol: properly detect ancestor socket pressure Message-ID: <20151114151518.GB28175@cmpxchg.org> References: <1447371693-25143-1-git-send-email-hannes@cmpxchg.org> <1447371693-25143-4-git-send-email-hannes@cmpxchg.org> <20151114124552.GI31308@esperanza> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151114124552.GI31308@esperanza> Sender: owner-linux-mm@kvack.org List-ID: To: Vladimir Davydov 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 Sat, Nov 14, 2015 at 03:45:52PM +0300, Vladimir Davydov wrote: > On Thu, Nov 12, 2015 at 06:41:22PM -0500, Johannes Weiner wrote: > > When charging socket memory, the code currently checks only the local > > page counter for excess to determine whether the memcg is under socket > > pressure. But even if the local counter is fine, one of the ancestors > > could have breached its limit, which should also force this child to > > enter socket pressure. This currently doesn't happen. > > > > Fix this by using page_counter_try_charge() first. If that fails, it > > means that either the local counter or one of the ancestors are in > > excess of their limit, and the child should enter socket pressure. > > > > Signed-off-by: Johannes Weiner > > Reviewed-by: Vladimir Davydov Thanks Vladimir! > For the record: it was broken by commit 3e32cb2e0a12 ("mm: memcontrol: > lockless page counters"). I didn't realize that. Fixes: 3e32cb2e0a12 ("mm: memcontrol: lockless page counters") -- 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