hrtimer: Add tracepoint for hrtimers

Add tracepoints which cover the life cycle of a hrtimer. The
tracepoints are integrated with the already existing debug_object
debug points as far as possible.

[ tglx: Fixed comments, made output conistent, easier to read and
  	parse. Fixed output for 32bit archs which do not use the
  	scalar representation of ktime_t. Hand current time to
  	trace_hrtimer_expiry_entry instead of calling get_time()
  	inside of the trace assignment. ]

Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Anton Blanchard <anton@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Zhaolei <zhaolei@cn.fujitsu.com>
LKML-Reference: <4A7F8B2B.5020908@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 139 insertions, 0 deletions

diff --git a/include/trace/events/timer.h b/include/trace/events/timer.h
index 725892a93b49..df3c07fa0cb8 100644
--- a/include/trace/events/timer.h
+++ b/include/trace/events/timer.h
@@ -5,6 +5,7 @@
 #define _TRACE_TIMER_H
 
 #include <linux/tracepoint.h>
+#include <linux/hrtimer.h>
 #include <linux/timer.h>
 
 /**
@@ -131,6 +132,144 @@ TRACE_EVENT(timer_cancel,
 	TP_printk("timer %p", __entry->timer)
 );
 
+/**
+ * hrtimer_init - called when the hrtimer is initialized
+ * @timer:	pointer to struct hrtimer
+ * @clockid:	the hrtimers clock
+ * @mode:	the hrtimers mode
+ */
+TRACE_EVENT(hrtimer_init,
+
+	TP_PROTO(struct hrtimer *timer, clockid_t clockid,
+		 enum hrtimer_mode mode),
+
+	TP_ARGS(timer, clockid, mode),
+
+	TP_STRUCT__entry(
+		__field( void *,		timer		)
+		__field( clockid_t,		clockid		)
+		__field( enum hrtimer_mode,	mode		)
+	),
+
+	TP_fast_assign(
+		__entry->timer		= timer;
+		__entry->clockid	= clockid;
+		__entry->mode		= mode;
+	),
+
+	TP_printk("hrtimer %p, clockid %s, mode %s", __entry->timer,
+		  __entry->clockid == CLOCK_REALTIME ?
+			"CLOCK_REALTIME" : "CLOCK_MONOTONIC",
+		  __entry->mode == HRTIMER_MODE_ABS ?
+			"HRTIMER_MODE_ABS" : "HRTIMER_MODE_REL")
+);
+
+/**
+ * hrtimer_start - called when the hrtimer is started
+ * @timer: pointer to struct hrtimer
+ */
+TRACE_EVENT(hrtimer_start,
+
+	TP_PROTO(struct hrtimer *timer),
+
+	TP_ARGS(timer),
+
+	TP_STRUCT__entry(
+		__field( void *,	timer		)
+		__field( void *,	function	)
+		__field( s64,		expires		)
+		__field( s64,		softexpires	)
+	),
+
+	TP_fast_assign(
+		__entry->timer		= timer;
+		__entry->function	= timer->function;
+		__entry->expires	= hrtimer_get_expires(timer).tv64;
+		__entry->softexpires	= hrtimer_get_softexpires(timer).tv64;
+	),
+
+	TP_printk("hrtimer %p, func %pf, expires %llu, softexpires %llu",
+		  __entry->timer, __entry->function,
+		  (unsigned long long)ktime_to_ns((ktime_t) {
+				  .tv64 = __entry->expires }),
+		  (unsigned long long)ktime_to_ns((ktime_t) {
+				  .tv64 = __entry->softexpires }))
+);
+
+/**
+ * htimmer_expire_entry - called immediately before the hrtimer callback
+ * @timer:	pointer to struct hrtimer
+ * @now:	pointer to variable which contains current time of the
+ *		timers base.
+ *
+ * Allows to determine the timer latency.
+ */
+TRACE_EVENT(hrtimer_expire_entry,
+
+	TP_PROTO(struct hrtimer *timer, ktime_t *now),
+
+	TP_ARGS(timer, now),
+
+	TP_STRUCT__entry(
+		__field( void *,	timer	)
+		__field( s64,		now	)
+	),
+
+	TP_fast_assign(
+		__entry->timer	= timer;
+		__entry->now	= now->tv64;
+	),
+
+	TP_printk("hrtimer %p, now %llu", __entry->timer,
+		  (unsigned long long)ktime_to_ns((ktime_t) {
+				  .tv64 = __entry->now }))
+ );
+
+/**
+ * hrtimer_expire_exit - called immediately after the hrtimer callback returns
+ * @timer:	pointer to struct hrtimer
+ *
+ * When used in combination with the hrtimer_expire_entry tracepoint we can
+ * determine the runtime of the callback function.
+ */
+TRACE_EVENT(hrtimer_expire_exit,
+
+	TP_PROTO(struct hrtimer *timer),
+
+	TP_ARGS(timer),
+
+	TP_STRUCT__entry(
+		__field( void *,	timer	)
+	),
+
+	TP_fast_assign(
+		__entry->timer	= timer;
+	),
+
+	TP_printk("hrtimer %p", __entry->timer)
+);
+
+/**
+ * hrtimer_cancel - called when the hrtimer is canceled
+ * @timer:	pointer to struct hrtimer
+ */
+TRACE_EVENT(hrtimer_cancel,
+
+	TP_PROTO(struct hrtimer *timer),
+
+	TP_ARGS(timer),
+
+	TP_STRUCT__entry(
+		__field( void *,	timer	)
+	),
+
+	TP_fast_assign(
+		__entry->timer	= timer;
+	),
+
+	TP_printk("hrtimer %p", __entry->timer)
+);
+
 #endif /*  _TRACE_TIMER_H */
 
 /* This part must be outside protection */