hi: 2012/5/23 Ezequiel Garcia <elezegarcia@xxxxxxxxx>: > Hi, > >>> Bingo! Because the driver will only submit *one* urb at a time, >>> how could it possible have more than one completion handlers >>> called at a time? >> >> how about multi-thread try to send urbs on the same pipe with the same >> complete function? > > Actually, I was wrong because my driver (being a video capture driver) > submits several > isoc urbs at the same time. > > I'm still not sure how this works regarding concurrency, but I guess > (or hope) the usb core calls > the completion handler one at a time OR the device sends interrupts > one at a time for each urb. take multi-core system for example, it is possible your completion handler execute at the same time, except you add a spin lock for activating your completion function. > > I know it's a terrible thing for me to guess (or hope), but these days > I've been testing > the driver under several conditions and it seems to work fine. > So I'm not worrying too much. > > If someone more knowledgeable reads this and can put a light upon this issue, > I would appreciate it. > > loody: Thanks for your answer regarding context ;) > Ezequiel. -- Regards, _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
