From: Steven Rostedt <srostedt@redhat.com>
Date: Fri, 15 May 2009 14:51:13 +0000 (-0400)
Subject: tracing: add previous task state info to sched switch event
X-Git-Tag: v2.6.31-rc1~401^2~27
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=937cdb9db7f59278d0cb1582e6e64e3dfd73b4fc;p=karo-tx-linux.git

tracing: add previous task state info to sched switch event

It is useful to see the state of a task that is being switched out.
This patch adds the output of the state of the previous task in
the context switch event.

[ Impact: see state of switched out task in context switch ]

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
---

diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index dd4033cf5b09..24ab5bcff7b2 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -156,6 +156,7 @@ TRACE_EVENT(sched_switch,
 		__array(	char,	prev_comm,	TASK_COMM_LEN	)
 		__field(	pid_t,	prev_pid			)
 		__field(	int,	prev_prio			)
+		__field(	long,	prev_state			)
 		__array(	char,	next_comm,	TASK_COMM_LEN	)
 		__field(	pid_t,	next_pid			)
 		__field(	int,	next_prio			)
@@ -165,13 +166,19 @@ TRACE_EVENT(sched_switch,
 		memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
 		__entry->prev_pid	= prev->pid;
 		__entry->prev_prio	= prev->prio;
+		__entry->prev_state	= prev->state;
 		memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
 		__entry->next_pid	= next->pid;
 		__entry->next_prio	= next->prio;
 	),
 
-	TP_printk("task %s:%d [%d] ==> %s:%d [%d]",
+	TP_printk("task %s:%d [%d] (%s) ==> %s:%d [%d]",
 		__entry->prev_comm, __entry->prev_pid, __entry->prev_prio,
+		__entry->prev_state ?
+		  __print_flags(__entry->prev_state, "|",
+				{ 1, "S"} , { 2, "D" }, { 4, "T" }, { 8, "t" },
+				{ 16, "Z" }, { 32, "X" }, { 64, "x" },
+				{ 128, "W" }) : "R",
 		__entry->next_comm, __entry->next_pid, __entry->next_prio)
 );