On Fri, Apr 13, 2018 at 12:47:45PM +0100, Patrick Bellasi wrote:
> In the past I remember some funny dance in cgroup callbacks when a
> task was terminating (like being moved in the root-rq just before
> exiting). But, as you say, if we always have the task_rq_lock we
> should be safe.
The syscall does the whole:
task_rq_lock();
queued = task_on_rq_queued();
running = task_current();
if (queued)
dequeue_task();
if (running)
put_prev_task();
/*
* task is in invariant state here,
* muck with it.
*/
if (queued)
enqueue_task();
if (running)
set_curr_task()
task_rq_unlock();
pattern; which because C sucks, we've not found a good template for yet.
Without the dequeue/put,enqueue/set you have to jump a few extra hoops.
