All of lore.kernel.org
 help / color / mirror / Atom feed
From: Michal Hocko <mhocko@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>,
	David Rientjes <rientjes@google.com>,
	Johannes Weiner <hannes@cmpxchg.org>, <linux-mm@kvack.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Michal Hocko <mhocko@suse.com>
Subject: [PATCH 3/3] oom, trace: add compaction retry tracepoint
Date: Wed, 14 Dec 2016 15:53:24 +0100	[thread overview]
Message-ID: <20161214145324.26261-4-mhocko@kernel.org> (raw)
In-Reply-To: <20161214145324.26261-1-mhocko@kernel.org>

From: Michal Hocko <mhocko@suse.com>

Higher order requests oom debugging is currently quite hard. We do have
some compaction points which can tell us how the compaction is operating
but there is no trace point to tell us about compaction retry logic.
This patch adds a one which will have the following format

            bash-3126  [001] ....  1498.220001: compact_retry: order=9 priority=COMPACT_PRIO_SYNC_LIGHT compaction_result=withdrawn retries=0 max_retries=16 should_retry=0

we can see that the order 9 request is not retried even though we are in
the highest compaction priority mode becase the last compaction attempt
was withdrawn. This means that compaction_zonelist_suitable must have
returned false and there is no suitable zone to compact for this request
and so no need to retry further.

another example would be
           <...>-3137  [001] ....    81.501689: compact_retry: order=9 priority=COMPACT_PRIO_SYNC_LIGHT compaction_result=failed retries=0 max_retries=16 should_retry=0

in this case the order-9 compaction failed to find any suitable
block. We do not retry anymore because this is a costly request
and those do not go below COMPACT_PRIO_SYNC_LIGHT priority.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 include/trace/events/mmflags.h | 26 ++++++++++++++++++++++++++
 include/trace/events/oom.h     | 39 +++++++++++++++++++++++++++++++++++++++
 mm/page_alloc.c                | 22 ++++++++++++++++------
 3 files changed, 81 insertions(+), 6 deletions(-)

diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h
index 7e4cfede873c..aa4caa6914a9 100644
--- a/include/trace/events/mmflags.h
+++ b/include/trace/events/mmflags.h
@@ -187,8 +187,32 @@ IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY,	"softdirty"	)		\
 	EM( COMPACT_NO_SUITABLE_PAGE,	"no_suitable_page")	\
 	EM( COMPACT_NOT_SUITABLE_ZONE,	"not_suitable_zone")	\
 	EMe(COMPACT_CONTENDED,		"contended")
+
+/* High-level compaction status feedback */
+#define COMPACTION_FAILED	1
+#define COMPACTION_WITHDRAWN	2
+#define COMPACTION_PROGRESS	3
+
+#define compact_result_to_feedback(result)	\
+({						\
+ 	enum compact_result __result = result;	\
+	(compaction_failed(__result)) ? COMPACTION_FAILED : \
+		(compaction_withdrawn(__result)) ? COMPACTION_WITHDRAWN : COMPACTION_PROGRESS; \
+})
+
+#define COMPACTION_FEEDBACK		\
+	EM(COMPACTION_FAILED,		"failed")	\
+	EM(COMPACTION_WITHDRAWN,	"withdrawn")	\
+	EMe(COMPACTION_PROGRESS,	"progress")
+
+#define COMPACTION_PRIORITY						\
+	EM(COMPACT_PRIO_SYNC_FULL,	"COMPACT_PRIO_SYNC_FULL")	\
+	EM(COMPACT_PRIO_SYNC_LIGHT,	"COMPACT_PRIO_SYNC_LIGHT")	\
+	EMe(COMPACT_PRIO_ASYNC,		"COMPACT_PRIO_ASYNC")
 #else
 #define COMPACTION_STATUS
+#define COMPACTION_PRIORITY
+#define COMPACTION_FEEDBACK
 #endif
 
 #ifdef CONFIG_ZONE_DMA
@@ -226,6 +250,8 @@ IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY,	"softdirty"	)		\
 #define EMe(a, b)	TRACE_DEFINE_ENUM(a);
 
 COMPACTION_STATUS
+COMPACTION_PRIORITY
+COMPACTION_FEEDBACK
 ZONE_TYPE
 
 /*
diff --git a/include/trace/events/oom.h b/include/trace/events/oom.h
index 9160da7a26a0..e9d690665b7a 100644
--- a/include/trace/events/oom.h
+++ b/include/trace/events/oom.h
@@ -69,6 +69,45 @@ TRACE_EVENT(reclaim_retry_zone,
 			__entry->no_progress_loops,
 			__entry->wmark_check)
 );
+
+#ifdef CONFIG_COMPACTION
+TRACE_EVENT(compact_retry,
+
+	TP_PROTO(int order,
+		enum compact_priority priority,
+		enum compact_result result,
+		int retries,
+		int max_retries,
+		bool ret),
+
+	TP_ARGS(order, priority, result, retries, max_retries, ret),
+
+	TP_STRUCT__entry(
+		__field(	int, order)
+		__field(	int, priority)
+		__field(	int, result)
+		__field(	int, retries)
+		__field(	int, max_retries)
+		__field(	bool, ret)
+	),
+
+	TP_fast_assign(
+		__entry->order = order;
+		__entry->priority = priority;
+		__entry->result = result;
+		__entry->retries = retries;
+		__entry->max_retries = max_retries;
+		__entry->ret = ret;
+	),
+
+	TP_printk("order=%d priority=%s compaction_result=%s retries=%d max_retries=%d should_retry=%d",
+			__entry->order,
+			__print_symbolic(__entry->priority, COMPACTION_PRIORITY),
+			__print_symbolic(__entry->result, COMPACTION_FEEDBACK),
+			__entry->retries, __entry->max_retries,
+			__entry->ret)
+);
+#endif /* CONFIG_COMPACTION */
 #endif
 
 /* This part must be outside protection */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 23ca951a8380..150245328882 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3201,6 +3201,9 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 {
 	int max_retries = MAX_COMPACT_RETRIES;
 	int min_priority;
+	bool ret = false;
+	int retries = *compaction_retries;
+	enum compact_priority priority = *compact_priority;
 
 	if (!order)
 		return false;
@@ -3222,8 +3225,10 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 	 * But do not retry if the given zonelist is not suitable for
 	 * compaction.
 	 */
-	if (compaction_withdrawn(compact_result))
-		return compaction_zonelist_suitable(ac, order, alloc_flags);
+	if (compaction_withdrawn(compact_result)) {
+		ret = compaction_zonelist_suitable(ac, order, alloc_flags);
+		goto out;
+	}
 
 	/*
 	 * !costly requests are much more important than __GFP_REPEAT
@@ -3235,8 +3240,10 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 	 */
 	if (order > PAGE_ALLOC_COSTLY_ORDER)
 		max_retries /= 4;
-	if (*compaction_retries <= max_retries)
-		return true;
+	if (*compaction_retries <= max_retries) {
+		ret = true;
+		goto out;
+	}
 
 	/*
 	 * Make sure there are attempts at the highest priority if we exhausted
@@ -3245,12 +3252,15 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 check_priority:
 	min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ?
 			MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY;
+
 	if (*compact_priority > min_priority) {
 		(*compact_priority)--;
 		*compaction_retries = 0;
-		return true;
+		ret = true;
 	}
-	return false;
+out:
+	trace_compact_retry(order, priority, compact_result, retries, max_retries, ret);
+	return ret;
 }
 #else
 static inline struct page *
-- 
2.10.2

WARNING: multiple messages have this Message-ID
From: Michal Hocko <mhocko@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>,
	David Rientjes <rientjes@google.com>,
	Johannes Weiner <hannes@cmpxchg.org>,
	linux-mm@kvack.org, LKML <linux-kernel@vger.kernel.org>,
	Michal Hocko <mhocko@suse.com>
Subject: [PATCH 3/3] oom, trace: add compaction retry tracepoint
Date: Wed, 14 Dec 2016 15:53:24 +0100	[thread overview]
Message-ID: <20161214145324.26261-4-mhocko@kernel.org> (raw)
In-Reply-To: <20161214145324.26261-1-mhocko@kernel.org>

From: Michal Hocko <mhocko@suse.com>

Higher order requests oom debugging is currently quite hard. We do have
some compaction points which can tell us how the compaction is operating
but there is no trace point to tell us about compaction retry logic.
This patch adds a one which will have the following format

            bash-3126  [001] ....  1498.220001: compact_retry: order=9 priority=COMPACT_PRIO_SYNC_LIGHT compaction_result=withdrawn retries=0 max_retries=16 should_retry=0

we can see that the order 9 request is not retried even though we are in
the highest compaction priority mode becase the last compaction attempt
was withdrawn. This means that compaction_zonelist_suitable must have
returned false and there is no suitable zone to compact for this request
and so no need to retry further.

another example would be
           <...>-3137  [001] ....    81.501689: compact_retry: order=9 priority=COMPACT_PRIO_SYNC_LIGHT compaction_result=failed retries=0 max_retries=16 should_retry=0

in this case the order-9 compaction failed to find any suitable
block. We do not retry anymore because this is a costly request
and those do not go below COMPACT_PRIO_SYNC_LIGHT priority.

Signed-off-by: Michal Hocko <mhocko@suse.com>
---
 include/trace/events/mmflags.h | 26 ++++++++++++++++++++++++++
 include/trace/events/oom.h     | 39 +++++++++++++++++++++++++++++++++++++++
 mm/page_alloc.c                | 22 ++++++++++++++++------
 3 files changed, 81 insertions(+), 6 deletions(-)

diff --git a/include/trace/events/mmflags.h b/include/trace/events/mmflags.h
index 7e4cfede873c..aa4caa6914a9 100644
--- a/include/trace/events/mmflags.h
+++ b/include/trace/events/mmflags.h
@@ -187,8 +187,32 @@ IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY,	"softdirty"	)		\
 	EM( COMPACT_NO_SUITABLE_PAGE,	"no_suitable_page")	\
 	EM( COMPACT_NOT_SUITABLE_ZONE,	"not_suitable_zone")	\
 	EMe(COMPACT_CONTENDED,		"contended")
+
+/* High-level compaction status feedback */
+#define COMPACTION_FAILED	1
+#define COMPACTION_WITHDRAWN	2
+#define COMPACTION_PROGRESS	3
+
+#define compact_result_to_feedback(result)	\
+({						\
+ 	enum compact_result __result = result;	\
+	(compaction_failed(__result)) ? COMPACTION_FAILED : \
+		(compaction_withdrawn(__result)) ? COMPACTION_WITHDRAWN : COMPACTION_PROGRESS; \
+})
+
+#define COMPACTION_FEEDBACK		\
+	EM(COMPACTION_FAILED,		"failed")	\
+	EM(COMPACTION_WITHDRAWN,	"withdrawn")	\
+	EMe(COMPACTION_PROGRESS,	"progress")
+
+#define COMPACTION_PRIORITY						\
+	EM(COMPACT_PRIO_SYNC_FULL,	"COMPACT_PRIO_SYNC_FULL")	\
+	EM(COMPACT_PRIO_SYNC_LIGHT,	"COMPACT_PRIO_SYNC_LIGHT")	\
+	EMe(COMPACT_PRIO_ASYNC,		"COMPACT_PRIO_ASYNC")
 #else
 #define COMPACTION_STATUS
+#define COMPACTION_PRIORITY
+#define COMPACTION_FEEDBACK
 #endif
 
 #ifdef CONFIG_ZONE_DMA
@@ -226,6 +250,8 @@ IF_HAVE_VM_SOFTDIRTY(VM_SOFTDIRTY,	"softdirty"	)		\
 #define EMe(a, b)	TRACE_DEFINE_ENUM(a);
 
 COMPACTION_STATUS
+COMPACTION_PRIORITY
+COMPACTION_FEEDBACK
 ZONE_TYPE
 
 /*
diff --git a/include/trace/events/oom.h b/include/trace/events/oom.h
index 9160da7a26a0..e9d690665b7a 100644
--- a/include/trace/events/oom.h
+++ b/include/trace/events/oom.h
@@ -69,6 +69,45 @@ TRACE_EVENT(reclaim_retry_zone,
 			__entry->no_progress_loops,
 			__entry->wmark_check)
 );
+
+#ifdef CONFIG_COMPACTION
+TRACE_EVENT(compact_retry,
+
+	TP_PROTO(int order,
+		enum compact_priority priority,
+		enum compact_result result,
+		int retries,
+		int max_retries,
+		bool ret),
+
+	TP_ARGS(order, priority, result, retries, max_retries, ret),
+
+	TP_STRUCT__entry(
+		__field(	int, order)
+		__field(	int, priority)
+		__field(	int, result)
+		__field(	int, retries)
+		__field(	int, max_retries)
+		__field(	bool, ret)
+	),
+
+	TP_fast_assign(
+		__entry->order = order;
+		__entry->priority = priority;
+		__entry->result = result;
+		__entry->retries = retries;
+		__entry->max_retries = max_retries;
+		__entry->ret = ret;
+	),
+
+	TP_printk("order=%d priority=%s compaction_result=%s retries=%d max_retries=%d should_retry=%d",
+			__entry->order,
+			__print_symbolic(__entry->priority, COMPACTION_PRIORITY),
+			__print_symbolic(__entry->result, COMPACTION_FEEDBACK),
+			__entry->retries, __entry->max_retries,
+			__entry->ret)
+);
+#endif /* CONFIG_COMPACTION */
 #endif
 
 /* This part must be outside protection */
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 23ca951a8380..150245328882 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3201,6 +3201,9 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 {
 	int max_retries = MAX_COMPACT_RETRIES;
 	int min_priority;
+	bool ret = false;
+	int retries = *compaction_retries;
+	enum compact_priority priority = *compact_priority;
 
 	if (!order)
 		return false;
@@ -3222,8 +3225,10 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 	 * But do not retry if the given zonelist is not suitable for
 	 * compaction.
 	 */
-	if (compaction_withdrawn(compact_result))
-		return compaction_zonelist_suitable(ac, order, alloc_flags);
+	if (compaction_withdrawn(compact_result)) {
+		ret = compaction_zonelist_suitable(ac, order, alloc_flags);
+		goto out;
+	}
 
 	/*
 	 * !costly requests are much more important than __GFP_REPEAT
@@ -3235,8 +3240,10 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 	 */
 	if (order > PAGE_ALLOC_COSTLY_ORDER)
 		max_retries /= 4;
-	if (*compaction_retries <= max_retries)
-		return true;
+	if (*compaction_retries <= max_retries) {
+		ret = true;
+		goto out;
+	}
 
 	/*
 	 * Make sure there are attempts at the highest priority if we exhausted
@@ -3245,12 +3252,15 @@ should_compact_retry(struct alloc_context *ac, int order, int alloc_flags,
 check_priority:
 	min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ?
 			MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY;
+
 	if (*compact_priority > min_priority) {
 		(*compact_priority)--;
 		*compaction_retries = 0;
-		return true;
+		ret = true;
 	}
-	return false;
+out:
+	trace_compact_retry(order, priority, compact_result, retries, max_retries, ret);
+	return ret;
 }
 #else
 static inline struct page *
-- 
2.10.2

--
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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2016-12-14 14:53 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-14 14:53 [PATCH 0/3] mm, oom: add oom detection tracepoints Michal Hocko
2016-12-14 14:53 ` Michal Hocko
2016-12-14 14:53 ` [PATCH 1/3] mm, trace: extract COMPACTION_STATUS and ZONE_TYPE to a common header Michal Hocko
2016-12-14 14:53   ` Michal Hocko
2016-12-14 17:14   ` Vlastimil Babka
2016-12-14 17:14     ` Vlastimil Babka
2016-12-14 17:32   ` kbuild test robot
2016-12-14 19:02     ` Michal Hocko
2016-12-14 19:02       ` Michal Hocko
2016-12-14 14:53 ` [PATCH 2/3] oom, trace: Add oom detection tracepoints Michal Hocko
2016-12-14 14:53   ` Michal Hocko
2016-12-14 17:17   ` Vlastimil Babka
2016-12-14 17:17     ` Vlastimil Babka
2016-12-14 14:53 ` Michal Hocko [this message]
2016-12-14 14:53   ` [PATCH 3/3] oom, trace: add compaction retry tracepoint Michal Hocko
2016-12-14 17:28   ` Vlastimil Babka
2016-12-14 17:28     ` Vlastimil Babka
2016-12-14 18:11     ` Michal Hocko
2016-12-14 18:11       ` Michal Hocko
2016-12-15  8:18       ` Vlastimil Babka
2016-12-15  8:18         ` Vlastimil Babka
2016-12-20 13:01 [PATCH 0/3 v2] mm, oom: add oom detection tracepoints Michal Hocko
2016-12-20 13:01 ` [PATCH 3/3] oom, trace: add compaction retry tracepoint Michal Hocko
2016-12-20 13:01   ` Michal Hocko
2017-01-04 10:47   ` Vlastimil Babka
2017-01-04 10:47     ` Vlastimil Babka
2017-01-04 10:56     ` Michal Hocko
2017-01-04 10:56       ` Michal Hocko
2017-01-04 14:49       ` Vlastimil Babka
2017-01-04 14:49         ` Vlastimil Babka

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20161214145324.26261-4-mhocko@kernel.org \
    --to=mhocko@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=hannes@cmpxchg.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mhocko@suse.com \
    --cc=rientjes@google.com \
    --cc=vbabka@suse.cz \
    --subject='Re: [PATCH 3/3] oom, trace: add compaction retry tracepoint' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.