From: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Date: Wed, 25 Mar 2015 14:29:38 +1030 > I note that there's still no comment saying "don't do this" in > netdevice.h; I gather returning NETDEV_TX_BUSY is still considered a Bad > Thing? You're not supposed to do it still, that's right. If the driver returns NETDEV_TX_BUSY it means that it is not maintaining the TX queues stop/start state properly. It was kept around for drivers that we didn't want to convert or fix up at the time (this is circa two decades ago). I realize that there are situations for some devices where this is difficult to achieve, but the stack really does a non-trivial amount of useless work if you don't play along nicely. If you grep drivers/net for it, the majority of the returns are in assertion failure paths in the TX handler of those drivers. NETDEV_TX_BUSY is not being returned in a normal path of operation. > (Does it really BUG_ON?) No, it doesn't. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
