On Monday 30 October 2000 19:46, Alan Cox wrote: > > Does this mean that someone should go over all video drivers and put > > locks into them ? > > If appropriate - you need locks anyway you can open once and read/write in > parallel in threaded apps Exactly for this reason I've made a patch, that takes a semaphore in read() and write(). Isn't the path important for performance the mmap() path ? Thus semaphores in read & write kill a whole number of races with a very small impact on performance. I could take out the exclusive open part or make it depend on a flag provided by the driver, if you think this to be important. But, frankly, I see no devices that would profit from that. Even radio cards can listen on one frequency if I am not mistaken. Regards Oliver
