mm/ksm: add tracepoint for ksm advisor

This adds a new tracepoint for the ksm advisor.  It reports the last scan
time, the new setting of the pages_to_scan parameter and the average cpu
percent usage of the ksmd background thread for the last scan.

Link: https://lkml.kernel.org/r/20231218231054.1625219-4-shr@devkernel.io
Signed-off-by: Stefan Roesch <shr@devkernel.io>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rik van Riel <riel@surriel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/mm/ksm.c b/mm/ksm.c
index ce3001745562..8fa6053a225d 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -458,6 +458,7 @@ static void scan_time_advisor(void)
 	advisor_ctx.cpu_time = cpu_time;
 
 	ksm_thread_pages_to_scan = pages;
+	trace_ksm_advisor(scan_time, pages, cpu_percent);
 }
 
 static void advisor_stop_scan(void)