For analysis of the timer wheel its necessary to trace the cascading. Add a tracepoint.
Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] --- include/trace/events/timer.h | 11 +++++++++++ kernel/time/timer.c | 1 + 2 files changed, 12 insertions(+) --- a/include/trace/events/timer.h +++ b/include/trace/events/timer.h @@ -126,6 +126,17 @@ DEFINE_EVENT(timer_class, timer_cancel, ); /** + * timer_cascade - called when the timer is cascaded + * @timer: pointer to struct timer_list + */ +DEFINE_EVENT(timer_class, timer_cascade, + + TP_PROTO(struct timer_list *timer), + + TP_ARGS(timer) +); + +/** * hrtimer_init - called when the hrtimer is initialized * @hrtimer: pointer to struct hrtimer * @clockid: the hrtimers clock --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1099,6 +1099,7 @@ static int cascade(struct tvec_base *bas * don't have to detach them individually. */ hlist_for_each_entry_safe(timer, tmp, &tv_list, entry) { + trace_timer_cascade(timer); /* No accounting, while moving them */ __internal_add_timer(base, timer); }
