[PATCH 24/28] mm, vmscan: Add classzone information to tracepoints

From: Mel Gorman
Date: Tue Apr 12 2016 - 06:46:46 EST


This is convenient when tracking down why the skip count is high because it'll
show what classzone kswapd woke up at and what zones are being isolated.

Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
---
include/trace/events/vmscan.h | 28 ++++++++++++++++++----------
mm/vmscan.c | 4 ++--
2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 897f1aa1ee5f..3d242fb8910a 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -55,21 +55,23 @@ TRACE_EVENT(mm_vmscan_kswapd_sleep,

TRACE_EVENT(mm_vmscan_kswapd_wake,

- TP_PROTO(int nid, int order),
+ TP_PROTO(int nid, int zid, int order),

- TP_ARGS(nid, order),
+ TP_ARGS(nid, zid, order),

TP_STRUCT__entry(
__field( int, nid )
+ __field( int, zid )
__field( int, order )
),

TP_fast_assign(
__entry->nid = nid;
+ __entry->zid = zid;
__entry->order = order;
),

- TP_printk("nid=%d order=%d", __entry->nid, __entry->order)
+ TP_printk("nid=%d zid=%d order=%d", __entry->nid, __entry->zid, __entry->order)
);

TRACE_EVENT(mm_vmscan_wakeup_kswapd,
@@ -266,16 +268,18 @@ TRACE_EVENT(mm_shrink_slab_end,

DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,

- TP_PROTO(int order,
+ TP_PROTO(int classzone_idx,
+ int order,
unsigned long nr_requested,
unsigned long nr_scanned,
unsigned long nr_taken,
isolate_mode_t isolate_mode,
int file),

- TP_ARGS(order, nr_requested, nr_scanned, nr_taken, isolate_mode, file),
+ TP_ARGS(classzone_idx, order, nr_requested, nr_scanned, nr_taken, isolate_mode, file),

TP_STRUCT__entry(
+ __field(int, classzone_idx)
__field(int, order)
__field(unsigned long, nr_requested)
__field(unsigned long, nr_scanned)
@@ -285,6 +289,7 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
),

TP_fast_assign(
+ __entry->classzone_idx = classzone_idx;
__entry->order = order;
__entry->nr_requested = nr_requested;
__entry->nr_scanned = nr_scanned;
@@ -293,8 +298,9 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,
__entry->file = file;
),

- TP_printk("isolate_mode=%d order=%d nr_requested=%lu nr_scanned=%lu nr_taken=%lu file=%d",
+ TP_printk("isolate_mode=%d classzone=%d order=%d nr_requested=%lu nr_scanned=%lu nr_taken=%lu file=%d",
__entry->isolate_mode,
+ __entry->classzone_idx,
__entry->order,
__entry->nr_requested,
__entry->nr_scanned,
@@ -304,27 +310,29 @@ DECLARE_EVENT_CLASS(mm_vmscan_lru_isolate_template,

DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_lru_isolate,

- TP_PROTO(int order,
+ TP_PROTO(int classzone_idx,
+ int order,
unsigned long nr_requested,
unsigned long nr_scanned,
unsigned long nr_taken,
isolate_mode_t isolate_mode,
int file),

- TP_ARGS(order, nr_requested, nr_scanned, nr_taken, isolate_mode, file)
+ TP_ARGS(classzone_idx, order, nr_requested, nr_scanned, nr_taken, isolate_mode, file)

);

DEFINE_EVENT(mm_vmscan_lru_isolate_template, mm_vmscan_memcg_isolate,

- TP_PROTO(int order,
+ TP_PROTO(int classzone_idx,
+ int order,
unsigned long nr_requested,
unsigned long nr_scanned,
unsigned long nr_taken,
isolate_mode_t isolate_mode,
int file),

- TP_ARGS(order, nr_requested, nr_scanned, nr_taken, isolate_mode, file)
+ TP_ARGS(classzone_idx, order, nr_requested, nr_scanned, nr_taken, isolate_mode, file)

);

diff --git a/mm/vmscan.c b/mm/vmscan.c
index dfd8bdfadfe4..e5aa605da6c4 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1417,7 +1417,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
if (!list_empty(&pages_skipped))
list_splice(&pages_skipped, src);
*nr_scanned = scan;
- trace_mm_vmscan_lru_isolate(sc->order, nr_to_scan, scan,
+ trace_mm_vmscan_lru_isolate(sc->reclaim_idx, sc->order, nr_to_scan, scan,
nr_taken, mode, is_file_lru(lru));
return nr_taken;
}
@@ -3402,7 +3402,7 @@ static int kswapd(void *p)
* Try reclaim the requested order but if that fails
* then try sleeping on the basis of the order reclaimed.
*/
- trace_mm_vmscan_kswapd_wake(pgdat->node_id, order);
+ trace_mm_vmscan_kswapd_wake(pgdat->node_id, classzone_idx, order);
if (balance_pgdat(pgdat, order, classzone_idx) < order)
goto kswapd_try_sleep;

--
2.6.4