[PATCH 2/2] tracing, vmscan: add comments for perf script page-reclaim

[Yafang Shao]

Currently there's no easy way to make perf scripts in sync with
tracepoints. One possible way is to run perf's tests regularly, another way
is once we changes the definitions of tracepoints we must keep in mind that
the perf scripts which are using these tracepoints must be changed as well.
So I add this comment for the new introduced page-reclaim script as a
reminder.

Signed-off-by: Yafang Shao <laoar.shao@xxxxxxxxx>
---
 include/trace/events/vmscan.h | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/vmscan.h b/include/trace/events/vmscan.h
index a5ab297..f0447ad 100644
--- a/include/trace/events/vmscan.h
+++ b/include/trace/events/vmscan.h
@@ -1,4 +1,17 @@
-/* SPDX-License-Identifier: GPL-2.0 */
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Bellow tracepoints are used by perf script page-reclaim:
+ *	mm_vmscan_direct_reclaim_begin
+ *	mm_vmscan_direct_reclaim_end
+ *	mm_vmscan_kswapd_wake
+ *	mm_vmscan_kswapd_sleep
+ *	mm_vmscan_wakeup_kswapd
+ *	mm_vmscan_lru_shrink_inactive
+ *	mm_vmscan_writepage
+ * We must keep the definitions of these tracepoints in sync with the perf
+ * script page-reclaim.
+ */
+
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM vmscan
 
-- 
1.8.3.1