On Mon, 2007-06-25 at 18:00 -0600, Jonathan Corbet wrote: > A couple of days ago I said: > > > The cafe_ccic (OLPC) camera driver uses a tasklet to move frames out of > > the DMA buffers in the streaming I/O path.... > > > > Obviously some testing is called for here. I will make an attempt to do > > that testing > > I've done that testing - I have an OLPC B3 unit running V2 of the > tasklet->workqueue patch, and all seems well. 30 FPS to the display and > no dropped frames. The tasklets/0 process is running 3-5% CPU, in case > that's interesting. For whatever reason, I see about 3% *more* idle > time when running just mplayer than I did without the patch. > > Consider my minor qualms withdrawn, there doesn't seem to be any trouble > in this area.
Jon, thanks a lot! This is great news. I wonder if converting tasklets to work queues also helps with other softirqs. Before, softirqs could not preempt a tasklet, since tasklets run as a softirq. With tasklets as work queues, what's left as a softirq can now preempt tasklets. Perhaps this can even help with performance. -- Steve - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
