[PATCH] sched/deadline: add GRUB bw change tracepoints

[Claudio Scordino]

This patch adds a tracepoint for tracing the total and running
bandwidths of GRUB's runqueue.

Signed-off-by: Claudio Scordino <claudio@xxxxxxxxxxxxxxx>
Signed-off-by: Juri Lelli <juri.lelli@xxxxxxx>
Signed-off-by: Luca Abeni <luca.abeni@xxxxxxxxxxxxxxx>
---
 include/trace/events/sched.h | 32 ++++++++++++++++++++++++++++++++
 kernel/sched/deadline.c      | 11 +++++++++++
 2 files changed, 43 insertions(+)

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index ae1409f..050fcb2 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -545,6 +545,38 @@ TRACE_EVENT(sched_swap_numa,
 			__entry->dst_cpu, __entry->dst_nid)
 );
 
+DECLARE_EVENT_CLASS(sched_dl_grub_template,
+
+	TP_PROTO(u64 this_bw, u64 running_bw, unsigned int cpu_id),
+
+	TP_ARGS(this_bw, running_bw, cpu_id),
+
+	TP_STRUCT__entry(
+		__field(u64,		this_bw)
+		__field(u64,		running_bw)
+		__field(u32,		cpu_id)
+	),
+
+	TP_fast_assign(
+		__entry->this_bw = this_bw;
+		__entry->running_bw = running_bw;
+		__entry->cpu_id = cpu_id;
+	),
+
+	TP_printk("total_bw=%llu running_bw=%llu cpu_id=%lu",
+		(unsigned long long)__entry->this_bw,
+		(unsigned long long)__entry->running_bw,
+		(unsigned long)__entry->cpu_id)
+);
+
+
+DEFINE_EVENT(sched_dl_grub_template, sched_dl_grub,
+
+	TP_PROTO(u64 this_bw, u64 running_bw, unsigned int cpu_id),
+
+	TP_ARGS(this_bw, running_bw, cpu_id)
+);
+
 /*
  * Tracepoint for waking a polling cpu without an IPI.
  */
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index a84299f..ae5c7ef 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -17,6 +17,7 @@
 #include "sched.h"
 
 #include <linux/slab.h>
+#include <trace/events/sched.h>
 #include <uapi/linux/sched/types.h>
 
 struct dl_bandwidth def_dl_bandwidth;
@@ -85,6 +86,8 @@ void add_running_bw(u64 dl_bw, struct dl_rq *dl_rq)
 	dl_rq->running_bw += dl_bw;
 	SCHED_WARN_ON(dl_rq->running_bw < old); /* overflow */
 	SCHED_WARN_ON(dl_rq->running_bw > dl_rq->this_bw);
+	trace_sched_dl_grub(dl_rq->this_bw, dl_rq->running_bw,
+			rq_of_dl_rq(dl_rq)->cpu);
 }
 
 static inline
@@ -97,6 +100,8 @@ void sub_running_bw(u64 dl_bw, struct dl_rq *dl_rq)
 	SCHED_WARN_ON(dl_rq->running_bw > old); /* underflow */
 	if (dl_rq->running_bw > old)
 		dl_rq->running_bw = 0;
+	trace_sched_dl_grub(dl_rq->this_bw, dl_rq->running_bw,
+			rq_of_dl_rq(dl_rq)->cpu);
 }
 
 static inline
@@ -107,6 +112,9 @@ void add_rq_bw(u64 dl_bw, struct dl_rq *dl_rq)
 	lockdep_assert_held(&(rq_of_dl_rq(dl_rq))->lock);
 	dl_rq->this_bw += dl_bw;
 	SCHED_WARN_ON(dl_rq->this_bw < old); /* overflow */
+	trace_sched_dl_grub(dl_rq->this_bw, dl_rq->running_bw,
+			rq_of_dl_rq(dl_rq)->cpu);
+
 }
 
 static inline
@@ -120,6 +128,9 @@ void sub_rq_bw(u64 dl_bw, struct dl_rq *dl_rq)
 	if (dl_rq->this_bw > old)
 		dl_rq->this_bw = 0;
 	SCHED_WARN_ON(dl_rq->running_bw > dl_rq->this_bw);
+	trace_sched_dl_grub(dl_rq->this_bw, dl_rq->running_bw,
+			rq_of_dl_rq(dl_rq)->cpu);
+
 }
 
 void dl_change_utilization(struct task_struct *p, u64 new_bw)
-- 
2.7.4