From: Soren Brinkmann <[email protected]> Date: Sun, 4 May 2014 15:43:02 -0700
> Under "heavy" RX load, the driver cannot handle the descriptors fast > enough. In detail, when a descriptor is consumed, its used flag is > cleared and once the RX budget is consumed all descriptors with a > cleared used flag are prepared to receive more data. Under load though, > the HW may constantly receive more data and use those descriptors with a > cleared used flag before they are actually prepared for next usage. > > The head and tail pointers into the RX-ring should always be valid and > we can omit clearing and checking of the used flag. > > Signed-off-by: Soren Brinkmann <[email protected]> Isn't the RX_USED bit the only thing that controls what RX entries the chip will try to use? I can't see how you can just remove the RX_USED bit handling altogether. The problem actually seems to be that in the current code we clear the RX_USED bit before we actually reallocate the buffer and set it up. It should be a bug to see the RX_USED bit set in gem_rx_refill(), and the only reason why it can happen is exactly because you're clearing it too early in gem_rx(). This change doesn't seem to be correct, I'm not applying this series sorry. -- 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/
