[PATCH v2 2/5] mm/compaction: enhance tracepoint output for compaction begin/end

Joonsoo Kim
2015-01-12T08:21:10Z

We now have tracepoint for begin event of compaction and it prints
start position of both scanners, but, tracepoint for end event of
compaction doesn't print finish position of both scanners. It'd be
also useful to know finish position of both scanners so this patch
add it. It will help to find odd behavior or problem on compaction
internal logic.

And, mode is added to both begin/end tracepoint output, since
according to mode, compaction behavior is quite different.

And, lastly, status format is changed to string rather than
status number for readability.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
---
include/linux/compaction.h | 2 ++
include/trace/events/compaction.h | 49 ++++++++++++++++++++++++++-----------
mm/compaction.c | 14 +++++++++--
3 files changed, 49 insertions(+), 16 deletions(-)

diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index 3238ffa..a9547b6 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -12,6 +12,7 @@
#define COMPACT_PARTIAL 3
/* The full zone was compacted */
#define COMPACT_COMPLETE 4
+/* When adding new state, please change compaction_status_string, too */

/* Used to signal whether compaction detected need_sched() or lock contention */
/* No contention detected */
@@ -22,6 +23,7 @@
#define COMPACT_CONTENDED_LOCK 2

#ifdef CONFIG_COMPACTION
+extern char *compaction_status_string[];
extern int sysctl_compact_memory;
extern int sysctl_compaction_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *length, loff_t *ppos);
diff --git a/include/trace/events/compaction.h b/include/trace/events/compaction.h
index 1337d9e..839f6fa 100644
--- a/include/trace/events/compaction.h
+++ b/include/trace/events/compaction.h
@@ -85,46 +85,67 @@ TRACE_EVENT(mm_compaction_migratepages,
);

TRACE_EVENT(mm_compaction_begin,
- TP_PROTO(unsigned long zone_start, unsigned long migrate_start,
- unsigned long free_start, unsigned long zone_end),
+ TP_PROTO(unsigned long zone_start, unsigned long migrate_pfn,
+ unsigned long free_pfn, unsigned long zone_end, bool sync),

- TP_ARGS(zone_start, migrate_start, free_start, zone_end),
+ TP_ARGS(zone_start, migrate_pfn, free_pfn, zone_end, sync),

TP_STRUCT__entry(
__field(unsigned long, zone_start)
- __field(unsigned long, migrate_start)
- __field(unsigned long, free_start)
+ __field(unsigned long, migrate_pfn)
+ __field(unsigned long, free_pfn)
__field(unsigned long, zone_end)
+ __field(bool, sync)
),

TP_fast_assign(
__entry->zone_start = zone_start;
- __entry->migrate_start = migrate_start;
- __entry->free_start = free_start;
+ __entry->migrate_pfn = migrate_pfn;
+ __entry->free_pfn = free_pfn;
__entry->zone_end = zone_end;
+ __entry->sync = sync;
),

- TP_printk("zone_start=0x%lx migrate_start=0x%lx free_start=0x%lx zone_end=0x%lx",
+ TP_printk("zone_start=0x%lx migrate_pfn=0x%lx free_pfn=0x%lx zone_end=0x%lx, mode=%s",
__entry->zone_start,
- __entry->migrate_start,
- __entry->free_start,
- __entry->zone_end)
+ __entry->migrate_pfn,
+ __entry->free_pfn,
+ __entry->zone_end,
+ __entry->sync ? "sync" : "async")
);

TRACE_EVENT(mm_compaction_end,
- TP_PROTO(int status),
+ TP_PROTO(unsigned long zone_start, unsigned long migrate_pfn,
+ unsigned long free_pfn, unsigned long zone_end, bool sync,
+ int status),

- TP_ARGS(status),
+ TP_ARGS(zone_start, migrate_pfn, free_pfn, zone_end, sync, status),

TP_STRUCT__entry(
+ __field(unsigned long, zone_start)
+ __field(unsigned long, migrate_pfn)
+ __field(unsigned long, free_pfn)
+ __field(unsigned long, zone_end)
+ __field(bool, sync)
__field(int, status)
),

TP_fast_assign(
+ __entry->zone_start = zone_start;
+ __entry->migrate_pfn = migrate_pfn;
+ __entry->free_pfn = free_pfn;
+ __entry->zone_end = zone_end;
+ __entry->sync = sync;
__entry->status = status;
),

- TP_printk("status=%d", __entry->status)
+ TP_printk("zone_start=0x%lx migrate_pfn=0x%lx free_pfn=0x%lx zone_end=0x%lx, mode=%s status=%s",
+ __entry->zone_start,
+ __entry->migrate_pfn,
+ __entry->free_pfn,
+ __entry->zone_end,
+ __entry->sync ? "sync" : "async",
+ compaction_status_string[__entry->status])
);

#endif /* _TRACE_COMPACTION_H */
diff --git a/mm/compaction.c b/mm/compaction.c
index 546e571..2d86a20 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -19,6 +19,14 @@
#include "internal.h"

#ifdef CONFIG_COMPACTION
+char *compaction_status_string[] = {
+ "deferred",
+ "skipped",
+ "continue",
+ "partial",
+ "complete",
+};
+
static inline void count_compact_event(enum vm_event_item item)
{
count_vm_event(item);
@@ -1197,7 +1205,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc)
zone->compact_cached_migrate_pfn[1] = cc->migrate_pfn;
}

- trace_mm_compaction_begin(start_pfn, cc->migrate_pfn, cc->free_pfn, end_pfn);
+ trace_mm_compaction_begin(start_pfn, cc->migrate_pfn,
+ cc->free_pfn, end_pfn, sync);

migrate_prep_local();

@@ -1299,7 +1308,8 @@ out:
zone->compact_cached_free_pfn = free_pfn;
}

- trace_mm_compaction_end(ret);
+ trace_mm_compaction_end(start_pfn, cc->migrate_pfn,
+ cc->free_pfn, end_pfn, sync, ret);

return ret;
}
--
1.7.9.5