[PATCH] vhost: try avoiding avail index access when getting descriptor

If last avail idx is not equal to cached avail idx, we're sure there's still available buffers in the virtqueue so there's no need to re-read avail idx. So let's skip this to avoid unnecessary userspace memory access and memory barrier. Pktgen test show about 3% improvement on rx pps.

Re: [PATCH 2/9] virtio_pci: use shared interrupts for virtqueues

On 2017年02月06日 01:15, Christoph Hellwig wrote: This lets IRQ layer handle dispatching IRQs to separate handlers for the case where we don't have per-VQ MSI-X vectors, and allows us to greatly simplify the code based on the assumption that we always have interrupt vector 0 (legacy INTx or

Re: [PATCH 1/9] virtio_pci: remove struct virtio_pci_vq_info

On 2017年02月06日 01:15, Christoph Hellwig wrote: We don't really need struct virtio_pci_vq_info, as most field in there are redundant: - the vq backpointer is not strictly neede to start with - the entry in the vqs list is not needed - the generic virtqueue already has list, we only

RE: [PATCH 05/14] netvsc: remove no longer needed receive staging buffers

The netvsc part is already in net-next. This patch is not needed. The part that removes the per-channel state can be in another patch. ___ Virtualization mailing list Virtualization@lists.linux-foundation.org

[PATCH] x86/paravirt: Avoid setting IF flag, if not necessary

Setting the IF flag can cause an VM exit. So we should avoid touching the IF flag until absolutely necessary. This patch change the way the paravirt arch_local_irq_restore() works by checking the previous flags value and call arch_local_irq_enable() only if the IF flag was set previously. On a 32