[PATCH 07/22] introduce TASK_UTRACED state

[Oleg Nesterov]

Introduce TASK_UTRACED state, will be used by utrace instead of TASK_TRACED.

Note: this state is reported as "t (tracing stop)" to the user-space to
avoid the confusion. IOW, it looks like TASK_TRACED in /proc/pid/status.

Signed-off-by: Oleg Nesterov <oleg(a)redhat.com&gt;
---
 fs/proc/array.c       |   11 ++++++-----
 include/linux/sched.h |   20 +++++++++++---------
 2 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/fs/proc/array.c b/fs/proc/array.c
index 496fef3..bfaa998 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -138,11 +138,12 @@ static const char * const task_state_array[] = {
 	"D (disk sleep)",	/*   2 */
 	"T (stopped)",		/*   4 */
 	"t (tracing stop)",	/*   8 */
-	"Z (zombie)",		/*  16 */
-	"X (dead)",		/*  32 */
-	"x (dead)",		/*  64 */
-	"K (wakekill)",		/* 128 */
-	"W (waking)",		/* 256 */
+	"t (tracing stop)",	/*  16 (stopped by utrace) */
+	"Z (zombie)",		/*  32 */
+	"X (dead)",		/*  64 */
+	"x (dead)",		/* 128 */
+	"K (wakekill)",		/* 256 */
+	"W (waking)",		/* 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 b87de83..7a0008c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -184,16 +184,17 @@ print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 #define TASK_UNINTERRUPTIBLE	2
 #define __TASK_STOPPED		4
 #define __TASK_TRACED		8
+#define __TASK_UTRACED		16
 /* in tsk->exit_state */
-#define EXIT_ZOMBIE		16
-#define EXIT_DEAD		32
+#define EXIT_ZOMBIE		32
+#define EXIT_DEAD		64
 /* in tsk->state again */
-#define TASK_DEAD		64
-#define TASK_WAKEKILL		128
-#define TASK_WAKING		256
-#define TASK_STATE_MAX		512
+#define TASK_DEAD		128
+#define TASK_WAKEKILL		256
+#define TASK_WAKING		512
+#define TASK_STATE_MAX		1024
 
-#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
+#define TASK_STATE_TO_CHAR_STR "RSDTtUZXxKW"
 
 extern char ___assert_task_state[1 - 2*!!(
 		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
@@ -202,15 +203,16 @@ extern char ___assert_task_state[1 - 2*!!(
 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
+#define TASK_UTRACED		(TASK_WAKEKILL | __TASK_UTRACED)
 
 /* Convenience macros for the sake of wake_up */
 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
-#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
+#define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED | __TASK_UTRACED)
 
 /* get_task_state() */
 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
-				 __TASK_TRACED)
+				 __TASK_TRACED | __TASK_UTRACED)
 
 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
-- 
1.5.5.1