[PATCH] SysRq-X: show blocked tasks

Add SysRq-X support: show blocked (TASK_UNINTERRUPTIBLE) tasks only.

Useful for debugging IO stalls.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 8 insertions, 3 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 12fdbef1d9bf..1848e280504d 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4804,7 +4804,7 @@ static void show_task(struct task_struct *p)
                 show_stack(p, NULL);
 }
 
-void show_state(void)
+void show_state_filter(unsigned long state_filter)
 {
         struct task_struct *g, *p;
 
@@ -4824,11 +4824,16 @@ void show_state(void)
                  * console might take alot of time:
                  */
                 touch_nmi_watchdog();
-                show_task(p);
+                if (p->state & state_filter)
+                        show_task(p);
         } while_each_thread(g, p);
 
         read_unlock(&tasklist_lock);
-        debug_show_all_locks();
+        /*
+         * Only show locks if all tasks are dumped:
+         */
+        if (state_filter == -1)
+                debug_show_all_locks();
 }
 
 /**