From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f170.google.com (mail-wi0-f170.google.com [209.85.212.170]) by kanga.kvack.org (Postfix) with ESMTP id 052056B00BB for ; Tue, 6 Jan 2015 06:27:47 -0500 (EST) Received: by mail-wi0-f170.google.com with SMTP id bs8so5873914wib.1 for ; Tue, 06 Jan 2015 03:27:46 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id v7si84173403wjr.16.2015.01.06.03.27.45 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 06 Jan 2015 03:27:45 -0800 (PST) Message-ID: <54ABC6AF.1020108@suse.cz> Date: Tue, 06 Jan 2015 12:27:43 +0100 From: Vlastimil Babka MIME-Version: 1.0 Subject: Re: [PATCH 3/3] mm/compaction: add tracepoint to observe behaviour of compaction defer References: <1417593127-6819-1-git-send-email-iamjoonsoo.kim@lge.com> <1417593127-6819-3-git-send-email-iamjoonsoo.kim@lge.com> In-Reply-To: <1417593127-6819-3-git-send-email-iamjoonsoo.kim@lge.com> Content-Type: text/plain; charset=iso-8859-2 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Joonsoo Kim , Andrew Morton Cc: Mel Gorman , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org On 12/03/2014 08:52 AM, Joonsoo Kim wrote: > compaction deferring logic is heavy hammer that block the way to > the compaction. It doesn't consider overall system state, so it > could prevent user from doing compaction falsely. In other words, > even if system has enough range of memory to compact, compaction would be > skipped due to compaction deferring logic. This patch add new tracepoint > to understand work of deferring logic. This will also help to check > compaction success and fail. > > Signed-off-by: Joonsoo Kim You only call the tracepoints from try_to_compact_pages(), but the corresponding functions are also called from elsewhere, e.g. kswapd. Shouldn't all be included? Otherwise one might consider the trace as showing a bug, where the defer state suddenly changed without being captured in the trace. -- 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