[PATCH 4/7] mm, vmscan: show LRU name in mm_vmscan_lru_isolate tracepoint

[Michal Hocko]

From: Michal Hocko <mhocko@xxxxxxxx>

mm_vmscan_lru_isolate currently prints only whether the LRU we isolate
from is file or anonymous but we do not know which LRU this is. It is
useful to know whether the list is file or anonymous as well. Change
the tracepoint to show symbolic names of the lru rather.

Signed-off-by: Michal Hocko <mhocko@xxxxxxxx>
---
 include/trace/events/vmscan.h | 20 ++++++++++++++------
 mm/vmscan.c                   |  2 +-
 2 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index 6af4dae46db2..cc0b4c456c78 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -36,6 +36,14 @@
 		(RECLAIM_WB_ASYNC) \
 	)
 
+#define show_lru_name(lru) \
+	__print_symbolic(lru, \
+			{LRU_INACTIVE_ANON, "LRU_INACTIVE_ANON"}, \
+			{LRU_ACTIVE_ANON, "LRU_ACTIVE_ANON"}, \
+			{LRU_INACTIVE_FILE, "LRU_INACTIVE_FILE"}, \
+			{LRU_ACTIVE_FILE, "LRU_ACTIVE_FILE"}, \
+			{LRU_UNEVICTABLE, "LRU_UNEVICTABLE"})
+
 TRACE_EVENT(mm_vmscan_kswapd_sleep,
 
 	TP_PROTO(int nid),
@@ -277,9 +285,9 @@ TRACE_EVENT(mm_vmscan_lru_isolate,
 		unsigned long nr_skipped,
 		unsigned long nr_taken,
 		isolate_mode_t isolate_mode,
-		int file),
+		int lru),
 
-	TP_ARGS(classzone_idx, order, nr_requested, nr_scanned, nr_skipped, nr_taken, isolate_mode, file),
+	TP_ARGS(classzone_idx, order, nr_requested, nr_scanned, nr_skipped, nr_taken, isolate_mode, lru),
 
 	TP_STRUCT__entry(
 		__field(int, classzone_idx)
@@ -289,7 +297,7 @@ TRACE_EVENT(mm_vmscan_lru_isolate,
 		__field(unsigned long, nr_skipped)
 		__field(unsigned long, nr_taken)
 		__field(isolate_mode_t, isolate_mode)
-		__field(int, file)
+		__field(int, lru)
 	),
 
 	TP_fast_assign(
@@ -300,10 +308,10 @@ TRACE_EVENT(mm_vmscan_lru_isolate,
 		__entry->nr_skipped = nr_skipped;
 		__entry->nr_taken = nr_taken;
 		__entry->isolate_mode = isolate_mode;
-		__entry->file = file;
+		__entry->lru = lru;
 	),
 
-	TP_printk("isolate_mode=%d classzone=%d order=%d nr_requested=%lu nr_scanned=%lu nr_skipped=%lu nr_taken=%lu file=%d",
+	TP_printk("isolate_mode=%d classzone=%d order=%d nr_requested=%lu nr_scanned=%lu nr_skipped=%lu nr_taken=%lu lru=%s",
 		__entry->isolate_mode,
 		__entry->classzone_idx,
 		__entry->order,
@@ -311,7 +319,7 @@ TRACE_EVENT(mm_vmscan_lru_isolate,
 		__entry->nr_scanned,
 		__entry->nr_skipped,
 		__entry->nr_taken,
-		__entry->file)
+		show_lru_name(__entry->lru))
 );
 
 TRACE_EVENT(mm_vmscan_writepage,
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4f7c0d66d629..3f0774f30a42 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1500,7 +1500,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 	}
 	*nr_scanned = scan + total_skipped;
 	trace_mm_vmscan_lru_isolate(sc->reclaim_idx, sc->order, nr_to_scan, scan,
-				    skipped, nr_taken, mode, is_file_lru(lru));
+				    skipped, nr_taken, mode, lru);
 	update_lru_sizes(lruvec, lru, nr_zone_taken, nr_taken);
 	return nr_taken;
 }
-- 
2.10.2