This adds a new tracepoint for the ksm advisor. It reports the last scan
time and the new setting of the pages_to_scan parameter.
Signed-off-by: Stefan Roesch <shr@xxxxxxxxxxxx>
---
include/trace/events/ksm.h | 28 ++++++++++++++++++++++++++++
mm/ksm.c | 2 ++
2 files changed, 30 insertions(+)
diff --git a/include/trace/events/ksm.h b/include/trace/events/ksm.h
index b5ac35c1d0e8..164133014922 100644
--- a/include/trace/events/ksm.h
+++ b/include/trace/events/ksm.h
@@ -245,6 +245,34 @@ TRACE_EVENT(ksm_remove_rmap_item,
__entry->pfn, __entry->rmap_item, __entry->mm)
);
+/**
+ * ksm_advisor - called after the advisor has run
+ *
+ * @scan_time: scan time in seconds
+ * @pages_to_scan: new pages_to_scan value
+ *
+ * Allows to trace the ksm advisor.
+ */
+TRACE_EVENT(ksm_advisor,
+
+ TP_PROTO(s64 scan_time, unsigned long pages_to_scan),
+
+ TP_ARGS(scan_time, pages_to_scan),
+
+ TP_STRUCT__entry(
+ __field(s64, scan_time)
+ __field(unsigned long, pages_to_scan)
+ ),
+
+ TP_fast_assign(
+ __entry->scan_time = scan_time;
+ __entry->pages_to_scan = pages_to_scan;
+ ),
+
+ TP_printk("ksm scan time %lld pages_to_scan %lu",
+ __entry->scan_time, __entry->pages_to_scan)
+);
+
#endif /* _TRACE_KSM_H */
/* This part must be outside protection */
diff --git a/mm/ksm.c b/mm/ksm.c
index 12e70f806b2b..93dff974f6ea 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -415,6 +415,8 @@ static void scan_time_advisor(s64 scan_time)
advisor_ctx.change = change;
advisor_ctx.scan_time = scan_time;
ksm_thread_pages_to_scan = pages;
+
+ trace_ksm_advisor(scan_time, pages);
}
static void run_advisor(void)
--
2.39.3
