torture: Wake up kthreads after storing task_struct pointer

Currently, _torture_create_kthread() uses kthread_run() to create
torture-test kthreads, which means that the resulting task_struct
pointer is stored after the newly created kthread has been marked
runnable.  This in turn can cause spurious failure of checks for
code being run by a particular kthread.  This commit therefore changes
_torture_create_kthread() to use kthread_create(), then to do an explicit
wake_up_process() after the task_struct pointer has been stored.

Reported-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
Paul E. McKenney 2022-01-03 06:07:09 -08:00
parent 89440d2dad
commit 6b8646a9d3

View file

@ -931,12 +931,14 @@ int _torture_create_kthread(int (*fn)(void *arg), void *arg, char *s, char *m,
int ret = 0;
VERBOSE_TOROUT_STRING(m);
*tp = kthread_run(fn, arg, "%s", s);
*tp = kthread_create(fn, arg, "%s", s);
if (IS_ERR(*tp)) {
ret = PTR_ERR(*tp);
TOROUT_ERRSTRING(f);
*tp = NULL;
return ret;
}
wake_up_process(*tp); // Process is sleeping, so ordering provided.
torture_shuffle_task_register(*tp);
return ret;
}