Hello, On Sun, Jan 18, 2015 at 12:46:51PM +0100, Arend van Spriel wrote: > On 01/18/15 12:17, Uwe Kleine-König wrote: > >Hello Wolfram, > > > >On Sun, Jan 18, 2015 at 12:06:58PM +0100, Wolfram Sang wrote: > >>On Sun, Jan 18, 2015 at 10:47:41AM +0100, Uwe Kleine-König wrote: > >>>On Sun, Jan 18, 2015 at 10:14:04AM +0100, Arend van Spriel wrote: > >>>>On 01/17/15 00:42, Ray Jui wrote: > >>>>>+ complete_all(&iproc_i2c->done); > >>>> > >>>>Looking over this code it seems to me there is always a single > >>>>process waiting for iproc_i2c->done to complete. So using complete() > >>>>here would suffice. > >>>Yeah, there is always only a single thread waiting. That means both > >>>complete and complete_all are suitable. AFAIK there is no reason to pick > >>>one over the other in this case. > >> > >>Clarity? > >And which do you consider more clear? complete_all might result in the > >question: "Is there>1 waiter?" and complete might yield to "What about > >the other waiters?". If you already know there is only one, both are on > >par on clarity. Might only be me?! I don't care much. > > Maybe it is me, but it is not about questions but it is about > implicit statements that the code makes (or reader derives from it). > When using complete_all you indicate to the reader "there can be > more than one waiter". When using complete it indicates "there is > only one waiter". If those statements are not true that is a code No, complete works just fine in the presence of >1 waiter. It just wakes a single waiter and all others continue to wait. That is, for single-waiter situations there is no semantic difference between complete and complete_all. But there is a difference for multi-waiter queues. I think this is just a matter of your POV in the single-waiter situation: complete might be intuitive because you just completed a single task and complete_all might be intuitive because it signals "I'm completely done, there is noone waiting for me any more.". Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
