Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751892AbaLCHsq (ORCPT ); Wed, 3 Dec 2014 02:48:46 -0500 Received: from lgeamrelo04.lge.com ([156.147.1.127]:43402 "EHLO lgeamrelo04.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751346AbaLCHsn (ORCPT ); Wed, 3 Dec 2014 02:48:43 -0500 X-Original-SENDERIP: 10.177.222.213 X-Original-MAILFROM: iamjoonsoo.kim@lge.com From: Joonsoo Kim To: Andrew Morton Cc: Vlastimil Babka , Mel Gorman , David Rientjes , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim Subject: [PATCH 3/3] mm/compaction: add tracepoint to observe behaviour of compaction defer Date: Wed, 3 Dec 2014 16:52:07 +0900 Message-Id: <1417593127-6819-3-git-send-email-iamjoonsoo.kim@lge.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1417593127-6819-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1417593127-6819-1-git-send-email-iamjoonsoo.kim@lge.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- include/trace/events/compaction.h | 56 +++++++++++++++++++++++++++++++++++++ mm/compaction.c | 7 ++++- 2 files changed, 62 insertions(+), 1 deletion(-) diff --git a/include/trace/events/compaction.h b/include/trace/events/compaction.h index 5e47cb2..673d59a 100644 --- a/include/trace/events/compaction.h +++ b/include/trace/events/compaction.h @@ -255,6 +255,62 @@ DEFINE_EVENT(mm_compaction_suitable_template, mm_compaction_suitable, TP_ARGS(zone, order, alloc_flags, classzone_idx, ret) ); +DECLARE_EVENT_CLASS(mm_compaction_defer_template, + + TP_PROTO(struct zone *zone, + unsigned int order), + + TP_ARGS(zone, order), + + TP_STRUCT__entry( + __field(char *, name) + __field(unsigned int, order) + __field(unsigned int, considered) + __field(unsigned int, defer_shift) + __field(int, order_failed) + ), + + TP_fast_assign( + __entry->name = (char *)zone->name; + __entry->order = order; + __entry->considered = zone->compact_considered; + __entry->defer_shift = zone->compact_defer_shift; + __entry->order_failed = zone->compact_order_failed; + ), + + TP_printk("zone=%-8s order=%u order_failed=%u reason=%s consider=%u limit=%lu", + __entry->name, + __entry->order, + __entry->order_failed, + __entry->order < __entry->order_failed ? "order" : "try", + __entry->considered, + 1UL << __entry->defer_shift) +); + +DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_deffered, + + TP_PROTO(struct zone *zone, + unsigned int order), + + TP_ARGS(zone, order) +); + +DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_defer_compaction, + + TP_PROTO(struct zone *zone, + unsigned int order), + + TP_ARGS(zone, order) +); + +DEFINE_EVENT(mm_compaction_defer_template, mm_compaction_defer_reset, + + TP_PROTO(struct zone *zone, + unsigned int order), + + TP_ARGS(zone, order) +); + #endif /* _TRACE_COMPACTION_H */ /* This part must be outside protection */ diff --git a/mm/compaction.c b/mm/compaction.c index f5d2405..e005620 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1413,8 +1413,10 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, int status; int zone_contended; - if (compaction_deferred(zone, order)) + if (compaction_deferred(zone, order)) { + trace_mm_compaction_deffered(zone, order); continue; + } status = compact_zone_order(zone, order, gfp_mask, mode, &zone_contended, alloc_flags, classzone_idx); @@ -1435,6 +1437,8 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, * succeeds in this zone. */ compaction_defer_reset(zone, order, false); + trace_mm_compaction_defer_reset(zone, order); + /* * It is possible that async compaction aborted due to * need_resched() and the watermarks were ok thanks to @@ -1456,6 +1460,7 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, * succeeding after all, it will be reset. */ defer_compaction(zone, order); + trace_mm_compaction_defer_compaction(zone, order); } /* -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/