[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>
diff --git a/drivers/char/sysrq.c b/drivers/char/sysrq.c
index c64f5bc..05810c8 100644
--- a/drivers/char/sysrq.c
+++ b/drivers/char/sysrq.c
@@ -182,6 +182,18 @@
.enable_mask = SYSRQ_ENABLE_DUMP,
};
+static void sysrq_handle_showstate_blocked(int key, struct tty_struct *tty)
+{
+ show_state_filter(TASK_UNINTERRUPTIBLE);
+}
+static struct sysrq_key_op sysrq_showstate_blocked_op = {
+ .handler = sysrq_handle_showstate_blocked,
+ .help_msg = "showBlockedTasks",
+ .action_msg = "Show Blocked State",
+ .enable_mask = SYSRQ_ENABLE_DUMP,
+};
+
+
static void sysrq_handle_showmem(int key, struct tty_struct *tty)
{
show_mem();
@@ -304,7 +316,7 @@
/* May be assigned at init time by SMP VOYAGER */
NULL, /* v */
NULL, /* w */
- NULL, /* x */
+ &sysrq_showstate_blocked_op, /* x */
NULL, /* y */
NULL /* z */
};