Sometimes it is necessary to understand in which memcg tracepoint event
occurred. The function cgroup_name() is a useful tool for this purpose.
To integrate cgroup_name() into the existing memcg tracepoints, this
patch introduces a new tracepoint template for the begin() and end()
events, utilizing static __array() to store the cgroup name.
Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxxxxx>
---
include/trace/events/vmscan.h | 77 +++++++++++++++++++++++++++++------
mm/vmscan.c | 8 ++--
2 files changed, 69 insertions(+), 16 deletions(-)
diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index d2123dd960d5..124bc22866c8 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -141,19 +141,47 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_direct_reclaim_b
);
#ifdef CONFIG_MEMCG
-DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin,
- TP_PROTO(int order, gfp_t gfp_flags),
+DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_begin_template,
- TP_ARGS(order, gfp_flags)
+ TP_PROTO(const struct mem_cgroup *memcg, int order, gfp_t gfp_flags),
+
+ TP_ARGS(memcg, order, gfp_flags),
+
+ TP_STRUCT__entry(
+ __field(int, order)
+ __field(unsigned long, gfp_flags)
+ __array(char, name, NAME_MAX + 1)
+ ),
+
+ TP_fast_assign(
+ __entry->order = order;
+ __entry->gfp_flags = (__force unsigned long)gfp_flags;
+ cgroup_name(memcg->css.cgroup,
+ __entry->name,
+ sizeof(__entry->name));
+ ),
+
+ TP_printk("memcg=%s order=%d gfp_flags=%s",
+ __entry->name,
+ __entry->order,
+ show_gfp_flags(__entry->gfp_flags))
);
-DEFINE_EVENT(mm_vmscan_direct_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin,
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template, mm_vmscan_memcg_reclaim_begin,
- TP_PROTO(int order, gfp_t gfp_flags),
+ TP_PROTO(const struct mem_cgroup *memcg, int order, gfp_t gfp_flags),
- TP_ARGS(order, gfp_flags)
+ TP_ARGS(memcg, order, gfp_flags)
+);
+
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_begin_template, mm_vmscan_memcg_softlimit_reclaim_begin,
+
+ TP_PROTO(const struct mem_cgroup *memcg, int order, gfp_t gfp_flags),
+
+ TP_ARGS(memcg, order, gfp_flags)
);
+
#endif /* CONFIG_MEMCG */
DECLARE_EVENT_CLASS(mm_vmscan_direct_reclaim_end_template,
@@ -181,19 +209,44 @@ DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_direct_reclaim_end
);
#ifdef CONFIG_MEMCG
-DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_reclaim_end,
- TP_PROTO(unsigned long nr_reclaimed),
+DECLARE_EVENT_CLASS(mm_vmscan_memcg_reclaim_end_template,
- TP_ARGS(nr_reclaimed)
+ TP_PROTO(const struct mem_cgroup *memcg, unsigned long nr_reclaimed),
+
+ TP_ARGS(memcg, nr_reclaimed),
+
+ TP_STRUCT__entry(
+ __field(unsigned long, nr_reclaimed)
+ __array(char, name, NAME_MAX + 1)
+ ),
+
+ TP_fast_assign(
+ __entry->nr_reclaimed = nr_reclaimed;
+ cgroup_name(memcg->css.cgroup,
+ __entry->name,
+ sizeof(__entry->name));
+ ),
+
+ TP_printk("memcg=%s nr_reclaimed=%lu",
+ __entry->name,
+ __entry->nr_reclaimed)
);
-DEFINE_EVENT(mm_vmscan_direct_reclaim_end_template, mm_vmscan_memcg_softlimit_reclaim_end,
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template, mm_vmscan_memcg_reclaim_end,
- TP_PROTO(unsigned long nr_reclaimed),
+ TP_PROTO(const struct mem_cgroup *memcg, unsigned long nr_reclaimed),
- TP_ARGS(nr_reclaimed)
+ TP_ARGS(memcg, nr_reclaimed)
);
+
+DEFINE_EVENT(mm_vmscan_memcg_reclaim_end_template, mm_vmscan_memcg_softlimit_reclaim_end,
+
+ TP_PROTO(const struct mem_cgroup *memcg, unsigned long nr_reclaimed),
+
+ TP_ARGS(memcg, nr_reclaimed)
+);
+
#endif /* CONFIG_MEMCG */
TRACE_EVENT(mm_shrink_slab_start,
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 1080209a568b..4309eaf188b4 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -7088,7 +7088,7 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
sc.gfp_mask = (gfp_mask & GFP_RECLAIM_MASK) |
(GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK);
- trace_mm_vmscan_memcg_softlimit_reclaim_begin(sc.order,
+ trace_mm_vmscan_memcg_softlimit_reclaim_begin(memcg, sc.order,
sc.gfp_mask);
/*
@@ -7100,7 +7100,7 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg,
*/
shrink_lruvec(lruvec, &sc);
- trace_mm_vmscan_memcg_softlimit_reclaim_end(sc.nr_reclaimed);
+ trace_mm_vmscan_memcg_softlimit_reclaim_end(memcg, sc.nr_reclaimed);
*nr_scanned = sc.nr_scanned;
@@ -7134,13 +7134,13 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg,
struct zonelist *zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
set_task_reclaim_state(current, &sc.reclaim_state);
- trace_mm_vmscan_memcg_reclaim_begin(0, sc.gfp_mask);
+ trace_mm_vmscan_memcg_reclaim_begin(memcg, 0, sc.gfp_mask);
noreclaim_flag = memalloc_noreclaim_save();
nr_reclaimed = do_try_to_free_pages(zonelist, &sc);
memalloc_noreclaim_restore(noreclaim_flag);
- trace_mm_vmscan_memcg_reclaim_end(nr_reclaimed);
+ trace_mm_vmscan_memcg_reclaim_end(memcg, nr_reclaimed);
set_task_reclaim_state(current, NULL);
return nr_reclaimed;
--
2.25.1
