Hey, I am studying the network performance between a pair of KVM workloads on different hosts. I have been looking into the RX, TX data path when a vhost-net driver is involved. I am intrigued why does a packet transmission from a guest run entirely in the context of the vhost thread. From what I could gather from the source, the vhost driver seems to write packets to the tap device using sendmsg. The tap device seems to enqueue it for napi to take over. I would have assumed that after sending the packet over the tap device, a softirq would have taken over but that doesn't happen. I am wondering how it that the entire packet is processed in the vhost kernel thread's context and would appreciate help! Thanks, Ritun -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
