On Mon 2015-10-05 12:07:58, Petr Mladek wrote: > On Fri 2015-10-02 15:24:53, Tejun Heo wrote: > > Hello, > > > > On Fri, Oct 02, 2015 at 05:43:36PM +0200, Petr Mladek wrote: > > > IMHO, we need both locks. The worker manipulates more works and > > > need its own lock. We need work-specific lock because the work > > > might be assigned to different workers and we need to be sure > > > that the operations are really serialized, e.g. queuing. > > > > I don't think we need per-work lock. Do we have such usage in kernel > > at all? If you're worried, let the first queueing record the worker > > and trigger warning if someone tries to queue it anywhere else. This > > doesn't need to be full-on general like workqueue. Let's make > > reasonable trade-offs where possible. > > I actually thought about this simplification as well. But then I am > in doubts about the API. It would make sense to assign the worker > when the work is being initialized and avoid the duplicate information > when the work is being queued: > > init_kthread_work(work, fn, worker); > queue_work(work); > > Or would you prefer to keep the API similar to workqueues even when > it makes less sense here? > > > In each case, we need a way to switch the worker if the old one > is destroyed and a new one is started later. We would need > something like: > > reset_work(work, worker) > or > reinit_work(work, fn, worker) I was too fast. We could set "work->worker = NULL" when the work finishes and it is not pending. It means that it will be connected to the particular worker only when used. Then we could keep the workqueues-like API and do not need reset_work(). I am going to play with this. I feel that it might work. Best Regards, Petr -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>