mm, vmscan: add classzone information to tracepoints

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.

Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Mel Gorman <[e-mail]>
Acked-by: Vlastimil Babka <[e-mail]>
Cc: Hillf Danton <[e-mail]>
Acked-by: Johannes Weiner <[e-mail]>
Cc: Joonsoo Kim <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Minchan Kim <[e-mail]>
Cc: Rik van Riel <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/trace/events/vmscan.h

···
 
 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,
···
 
 DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_begin_template,
 
-	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags),
+	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags, int classzone_idx),
 
-	TP_ARGS(order, may_writepage, gfp_flags),
+	TP_ARGS(order, may_writepage, gfp_flags, classzone_idx),
 
 	TP_STRUCT__entry(
 		__field(	int,	order		)
 		__field(	int,	may_writepage	)
 		__field(	gfp_t,	gfp_flags	)
+		__field(	int,	classzone_idx	)
 	),
 
 	TP_fast_assign(
 		__entry->order		= order;
 		__entry->may_writepage	= may_writepage;
 		__entry->gfp_flags	= gfp_flags;
+		__entry->classzone_idx	= classzone_idx;
 	),
 
-	TP_printk("order=%d may_writepage=%d gfp_flags=%s",
+	TP_printk("order=%d may_writepage=%d gfp_flags=%s classzone_idx=%d",
 		__entry->order,
 		__entry->may_writepage,
-		show_gfp_flags(__entry->gfp_flags))
+		show_gfp_flags(__entry->gfp_flags),
+		__entry->classzone_idx)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_direct_reclaim_begin,
 
-	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags),
+	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags, int classzone_idx),
 
-	TP_ARGS(order, may_writepage, gfp_flags)
+	TP_ARGS(order, may_writepage, gfp_flags, classzone_idx)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin,
 
-	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags),
+	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags, int classzone_idx),
 
-	TP_ARGS(order, may_writepage, gfp_flags)
+	TP_ARGS(order, may_writepage, gfp_flags, classzone_idx)
 );
 
 DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin,
 
-	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags),
+	TP_PROTO(int order, int may_writepage, gfp_t gfp_flags, int classzone_idx),
 
-	TP_ARGS(order, may_writepage, gfp_flags)
+	TP_ARGS(order, may_writepage, gfp_flags, classzone_idx)
 );
 
 DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_end_template,
···
 
 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)
···
 	),
 
 	TP_fast_assign(
+		__entry->classzone_idx = classzone_idx;
 		__entry->order = order;
 		__entry->nr_requested = nr_requested;
 		__entry->nr_scanned = nr_scanned;
···
 		__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,
···
 
 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)
 
 );
 

mm/vmscan.c

···
 	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));
 	for (scan = 0; scan < MAX_NR_ZONES; scan++) {
 		nr_pages = nr_zone_taken[scan];
···
 
 	trace_mm_vmscan_direct_reclaim_begin(order,
 				sc.may_writepage,
-				gfp_mask);
+				gfp_mask,
+				sc.reclaim_idx);
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
···
 
 	trace_mm_vmscan_memcg_softlimit_reclaim_begin(sc.order,
 						      sc.may_writepage,
-						      sc.gfp_mask);
+						      sc.gfp_mask,
+						      sc.reclaim_idx);
 
 	/*
 	 * NOTE: Although we can get the priority field, using it
···
 
 	trace_mm_vmscan_memcg_reclaim_begin(0,
 					    sc.may_writepage,
-					    sc.gfp_mask);
+					    sc.gfp_mask,
+					    sc.reclaim_idx);
 
 	nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
 
···
 		 * but kcompactd is woken to compact for the original
 		 * request (alloc_order).
 		 */
-		trace_mm_vmscan_kswapd_wake(pgdat->node_id, alloc_order);
+		trace_mm_vmscan_kswapd_wake(pgdat->node_id, classzone_idx,
+						alloc_order);
 		reclaim_order = balance_pgdat(pgdat, alloc_order, classzone_idx);
 		if (reclaim_order < alloc_order)
 			goto kswapd_try_sleep;