From: Jason Baron <jbaron@redhat.com>
Date: Fri, 4 Dec 2009 15:58:58 -0500
Subject: [misc] timer: add tracepoints
Message-id: <20091204155857.GA30969@redhat.com>
Patchwork-id: 21687
O-Subject: [RHEL5.5 PATCH] tracepoint: add timer tracepoints
Bugzilla: 534178

hi,

In addition to the itimer tracepoints, these additional timer
tracepoints were also requested by Fujitsu for RHEL5.5 inclusion. These
are taken directly from upstream. I've done basic sanity testing using
Systemtap, and verified the build with a brew build. Applies on top of
the 'itimer' tracepoints previously posted. BZ #534178.

thanks,

-Jason

Signed-off-by: Don Zickus <dzickus@redhat.com>

diff --git a/include/trace/timer.h b/include/trace/timer.h
index d1699d6..3bcd065 100644
--- a/include/trace/timer.h
+++ b/include/trace/timer.h
@@ -10,6 +10,21 @@ DEFINE_TRACE(itimer_state,
 DEFINE_TRACE(itimer_expire,
 	TPPROTO(int which, struct signal_struct *sig, cputime_t now),
 	TPARGS(which, sig, now));
+DEFINE_TRACE(timer_expire_entry,
+	TPPROTO(struct timer_list *timer),
+	TPARGS(timer));
+DEFINE_TRACE(timer_expire_exit,
+	TPPROTO(struct timer_list *timer),
+	TPARGS(timer));
+DEFINE_TRACE(timer_init,
+	TPPROTO(struct timer_list *timer),
+	TPARGS(timer));
+DEFINE_TRACE(timer_start,
+	TPPROTO(struct timer_list *timer, unsigned long expires),
+	TPARGS(timer, expires));
+DEFINE_TRACE(timer_cancel,
+	TPPROTO(struct timer_list *timer),
+	TPARGS(timer));
 
 
 #endif
diff --git a/kernel/timer.c b/kernel/timer.c
index 0e831b5..9fd8718 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -42,6 +42,8 @@
 #include <asm/timex.h>
 #include <asm/io.h>
 
+#include <trace/timer.h>
+
 #ifdef CONFIG_TIME_INTERPOLATION
 static void time_interpolator_update(long delta_nsec);
 #else
@@ -277,6 +279,7 @@ static void internal_add_timer(tvec_base_t *base, struct timer_list *timer)
  */
 void fastcall init_timer(struct timer_list *timer)
 {
+	trace_timer_init(timer);
 	timer->entry.next = NULL;
 	timer->base = __raw_get_cpu_var(tvec_bases);
 }
@@ -287,6 +290,8 @@ static inline void detach_timer(struct timer_list *timer,
 {
 	struct list_head *entry = &timer->entry;
 
+	trace_timer_cancel(timer);
+
 	__list_del(entry->prev, entry->next);
 	if (clear_pending)
 		entry->next = NULL;
@@ -338,6 +343,8 @@ int __mod_timer(struct timer_list *timer, unsigned long expires)
 		ret = 1;
 	}
 
+	trace_timer_start(timer, expires);
+
 	new_base = __get_cpu_var(tvec_bases);
 
 	if (base != new_base) {
@@ -382,6 +389,7 @@ void add_timer_on(struct timer_list *timer, int cpu)
   	BUG_ON(timer_pending(timer) || !timer->function);
 	spin_lock_irqsave(&base->lock, flags);
 	timer->base = base;
+	trace_timer_start(timer, timer->expires);
 	internal_add_timer(base, timer);
 	spin_unlock_irqrestore(&base->lock, flags);
 }
@@ -575,7 +583,9 @@ static inline void __run_timers(tvec_base_t *base)
 			spin_unlock_irq(&base->lock);
 			{
 				int preempt_count = preempt_count();
+				trace_timer_expire_entry(timer);
 				fn(data);
+				trace_timer_expire_exit(timer);
 				if (preempt_count != preempt_count()) {
 					printk(KERN_WARNING "huh, entered %p "
 					       "with preempt_count %08x, exited"