On Fri, 08 Mar 2024 13:38:20 -0500 Steven Rostedt rostedt@goodmis.org wrote:
+static DEFINE_MUTEX(wait_mutex);
+static bool wait_woken_prepare(struct trace_iterator *iter, int *wait_index) +{
- bool woken = false;
- mutex_lock(&wait_mutex);
- if (iter->waking)
woken = true;- *wait_index = iter->wait_index;
- mutex_unlock(&wait_mutex);
- return woken;
+}
The last patch adds this code after a prepare_to_wait(), which triggered the warning:
do not call blocking ops when !TASK_RUNNING; state=1 set at [<00000000797e3e20>] prepare_to_wait+0x48/0xf0
Which is correct. The prepare_to_wait() set task state to TASK_INTERRUPTIBLE, so I can not call a mutex after that.
I'll send a v2 where I switch this over to spin locks.
-- Steve
+static bool wait_woken_check(struct trace_iterator *iter, int *wait_index) +{
- bool woken = false;
- mutex_lock(&wait_mutex);
- if (iter->waking || *wait_index != iter->wait_index)
woken = true;- mutex_unlock(&wait_mutex);
- return woken;
+}
+static void wait_woken_set(struct trace_iterator *iter) +{
- mutex_lock(&wait_mutex);
- iter->waking++;
- iter->wait_index++;
- mutex_unlock(&wait_mutex);
+}
+static void wait_woken_clear(struct trace_iterator *iter) +{
- mutex_lock(&wait_mutex);
- iter->waking--;
- mutex_unlock(&wait_mutex);
+}