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Diffstat (limited to 'kernel/hung_task.c')
-rw-r--r--kernel/hung_task.c27
1 files changed, 23 insertions, 4 deletions
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index b2fc2727d654..04efa7a6e69b 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -31,6 +31,11 @@
static int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;
/*
+ * Total number of tasks detected as hung since boot:
+ */
+static unsigned long __read_mostly sysctl_hung_task_detect_count;
+
+/*
* Limit number of tasks checked in a batch.
*
* This value controls the preemptibility of khungtaskd since preemption
@@ -115,6 +120,12 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
if (time_is_after_jiffies(t->last_switch_time + timeout * HZ))
return;
+ /*
+ * This counter tracks the total number of tasks detected as hung
+ * since boot.
+ */
+ sysctl_hung_task_detect_count++;
+
trace_sched_process_hang(t);
if (sysctl_hung_task_panic) {
@@ -127,7 +138,7 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
* Ok, the task did not get scheduled for more than 2 minutes,
* complain:
*/
- if (sysctl_hung_task_warnings) {
+ if (sysctl_hung_task_warnings || hung_task_call_panic) {
if (sysctl_hung_task_warnings > 0)
sysctl_hung_task_warnings--;
pr_err("INFO: task %s:%d blocked for more than %ld seconds.\n",
@@ -136,6 +147,8 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
print_tainted(), init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
init_utsname()->version);
+ if (t->flags & PF_POSTCOREDUMP)
+ pr_err(" Blocked by coredump.\n");
pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
" disables this message.\n");
sched_show_task(t);
@@ -239,7 +252,7 @@ static long hung_timeout_jiffies(unsigned long last_checked,
/*
* Process updating of timeout sysctl
*/
-static int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
+static int proc_dohung_task_timeout_secs(const struct ctl_table *table, int write,
void *buffer,
size_t *lenp, loff_t *ppos)
{
@@ -261,7 +274,7 @@ static int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
* and hung_task_check_interval_secs
*/
static const unsigned long hung_task_timeout_max = (LONG_MAX / HZ);
-static struct ctl_table hung_task_sysctls[] = {
+static const struct ctl_table hung_task_sysctls[] = {
#ifdef CONFIG_SMP
{
.procname = "hung_task_all_cpu_backtrace",
@@ -314,7 +327,13 @@ static struct ctl_table hung_task_sysctls[] = {
.proc_handler = proc_dointvec_minmax,
.extra1 = SYSCTL_NEG_ONE,
},
- {}
+ {
+ .procname = "hung_task_detect_count",
+ .data = &sysctl_hung_task_detect_count,
+ .maxlen = sizeof(unsigned long),
+ .mode = 0444,
+ .proc_handler = proc_doulongvec_minmax,
+ },
};
static void __init hung_task_sysctl_init(void)