08.04.2020 03:00, Sowjanya Komatineni пишет: ... >>>>> I suppose that taking a shot takes at least few milliseconds, which >>>>> should be unacceptable to waste. >>>> As long as buffers are in queue we have to keep processing each >>>> buffer and between buffers obviously we have to wait for previous >>>> frames to finish and this why we have separate thread for frame >>>> finish where we can have next buffer capture ready and issue while >>>> previous frame memory write happens >> Also we specified numbers buffers as 3 to vb2 queue. So this is rare >> case but to prevent issuing more than 2 at a time as VI HW is only >> double buffered and syncpt fifo max depth is 2 added this to be safer. > > To be more clear, when more buffers are enqueued from userspace always > capture list will be full and thread will be busy in capture till either > error or stop stream request happens. > If kthreads take more than 1% of CPU time during capture (video) with more than 2 buffers in queue, then it's not good and I think you should do something about it. If kthreads stay at ~0%, then it should be okay as-is.
