sched-Fix-taskstates-in-sched_switch-and-proc.patch

From baf11f6734078890a646a7b62f73f805ede5bf69 Mon Sep 17 00:00:00 2001
From: Carsten Emde <C.Emde@osadl.org>
Date: Wed, 24 Feb 2010 09:51:14 +0100
Subject: [PATCH] sched: Fix taskstates in sched_switch and proc

commit d740a0190499992ffc6fca56922b1771bdb77189 in tip.

The sched_switch trace event displays erroneous character codes of task
states, after a new task state was added in the scheduler code but
omitted to add in the trace event code.

Define character codes of task states individually. In addition, define
task state descriptions needed in /proc at the same place. This will
help to keep the task state bits, characters and descriptions in sync
should they ever need to be changed again.

[PG: delete duplicate #define TASK_STATE_MAX in original]

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 382f0ff..768d3e2 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -129,22 +129,23 @@ static inline void task_name(struct seq_file *m, struct task_struct *p)
 
 /*
  * The task state array is a strange "bitmap" of
- * reasons to sleep. Thus "running" is zero, and
- * you can test for combinations of others with
+ * reasons to sleep. Thus, the first element is zero,
+ * and you can test for combinations of others with
  * simple bit tests.
  */
+#define TASK_STATE_X(num) TASK_STATE_##num " (" DESCR_TASK_STATE_##num ")"
 static const char *task_state_array[] = {
-	"R (running)",		/*   0 */
-	"M (running-mutex)",	/*   1 */
-	"S (sleeping)",		/*   2 */
-	"D (disk sleep)",	/*   4 */
-	"T (stopped)",		/*   8 */
-	"T (tracing stop)",	/*  16 */
-	"Z (zombie)",		/*  32 */
-	"X (dead)",		/*  64 */
-	"x (dead)",		/*  64 */
-	"K (wakekill)",		/* 128 */
-	"W (waking)",		/* 256 */
+	TASK_STATE_X(0),
+	TASK_STATE_X(1),
+	TASK_STATE_X(2),
+	TASK_STATE_X(4),
+	TASK_STATE_X(8),
+	TASK_STATE_X(16),
+	TASK_STATE_X(32),
+	TASK_STATE_X(64),
+	TASK_STATE_X(128),
+	TASK_STATE_X(256),
+	TASK_STATE_X(512)
 };
 
 static inline const char *get_task_state(struct task_struct *tsk)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 77166d7..18ae27a 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -191,7 +191,9 @@ extern struct mutex kernel_sem;
 
 /*
  * Task state bitmask. NOTE! These bits are also
- * encoded in fs/proc/array.c: get_task_state().
+ * used in fs/proc/array.c: get_task_state() and
+ * in include/trace/events/sched.h in the
+ * sched_switch trace event.
  *
  * We have two separate sets of flags: task->state
  * is about runnability, while task->exit_state are
@@ -200,21 +202,57 @@ extern struct mutex kernel_sem;
  * mistake.
  */
 #define TASK_RUNNING		0
+#define TASK_STATE_0		"R"
+#define DESCR_TASK_STATE_0	"running"
+
 #define TASK_RUNNING_MUTEX	1
+#define TASK_STATE_1		"M"
+#define DESCR_TASK_STATE_1	"running-mutex"
+
 #define TASK_INTERRUPTIBLE	2
+#define TASK_STATE_2		"S"
+#define DESCR_TASK_STATE_2	"sleeping"
+
 #define TASK_UNINTERRUPTIBLE	4
+#define TASK_STATE_4		"D"
+#define DESCR_TASK_STATE_4	"disk sleep"
+
 #define __TASK_STOPPED		8
+#define TASK_STATE_8		"T"
+#define DESCR_TASK_STATE_8	"stopped"
+
 #define __TASK_TRACED		16
+#define TASK_STATE_16		"t"
+#define DESCR_TASK_STATE_16	"tracing stop"
+
 /* in tsk->exit_state */
 #define EXIT_ZOMBIE		32
+#define TASK_STATE_32		"Z"
+#define DESCR_TASK_STATE_32	"zombie"
+
 #define EXIT_DEAD		64
+#define TASK_STATE_64		"X"
+#define DESCR_TASK_STATE_64	"dead"
+
 /* in tsk->state again */
 #define TASK_DEAD		128
+#define TASK_STATE_128		"x"
+#define DESCR_TASK_STATE_128	"dead"
+
 #define TASK_WAKEKILL		256
+#define TASK_STATE_256		"K"
+#define DESCR_TASK_STATE_256	"wakekill"
+
 #define TASK_WAKING		512
+#define TASK_STATE_512		"W"
+#define DESCR_TASK_STATE_512	"waking"
+
 #define TASK_STATE_MAX		1024
 
-#define TASK_STATE_TO_CHAR_STR "RMSDTtZXxKW"
+#define TASK_STATE_TO_CHAR_STR \
+  TASK_STATE_0 TASK_STATE_1 TASK_STATE_2 TASK_STATE_4 TASK_STATE_8 \
+  TASK_STATE_16 TASK_STATE_32 TASK_STATE_64 TASK_STATE_128 TASK_STATE_256 \
+  TASK_STATE_512
 
 extern char ___assert_task_state[1 - 2*!!(
 		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
index 354e98f..ad2ae91 100644
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -161,9 +161,12 @@ TRACE_EVENT(sched_switch,
 		__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",
+			{ 1, TASK_STATE_1} , { 2, TASK_STATE_2 },
+			{ 4, TASK_STATE_4 }, { 8, TASK_STATE_8 },
+			{ 16, TASK_STATE_16 }, { 32, TASK_STATE_32 },
+			{ 64, TASK_STATE_64 }, { 128, TASK_STATE_128 },
+			{ 256, TASK_STATE_256 }, { 512, TASK_STATE_512 }
+			) : TASK_STATE_0,
 		__entry->next_comm, __entry->next_pid, __entry->next_prio)
 );
 
-- 
1.7.1.1