user/sven/linux.git/include/linux/virtio_ring.h, branch stable/4.2.y

virtio_ring: Update weak barriers to use dma_wmb/rmb

2015-04-13T11:34:16Z

This change makes it so that instead of using smp_wmb/rmb which varies depending on the kernel configuration we can can use dma_wmb/rmb which for most architectures should be equal to or slightly more strict than smp_wmb/rmb. The advantage to this is that these barriers are available to uniprocessor builds as well so the performance should improve under such a configuration. Signed-off-by: Alexander Duyck Signed-off-by: Rusty Russell

virtio_ring: change host notification API

2013-10-29T00:58:11Z

Currently a host kick error is silently ignored and not reflected in the virtqueue of a particular virtio device. Changing the notify API for guest->host notification seems to be one prerequisite in order to be able to handle such errors in the context where the kick is triggered. This patch changes the notify API. The notify function must return a bool return value. It returns false if the host notification failed. Signed-off-by: Heinz Graalfs Signed-off-by: Rusty Russell

virtio: include asm/barrier explicitly

2013-07-09T01:17:53Z

virtio_ring.h uses mb() and friends, make it pull in asm/barrier.h itself, not rely on other headers to do it. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

virtio_ring: expose virtio barriers for use in vringh.

2013-03-20T03:30:41Z

The host side of ring needs this logic too. Signed-off-by: Rusty Russell

UAPI: (Scripted) Disintegrate include/linux

2012-10-13T09:46:48Z

Signed-off-by: David Howells Acked-by: Arnd Bergmann Acked-by: Thomas Gleixner Acked-by: Michael Kerrisk Acked-by: Paul E. McKenney Acked-by: Dave Jones

virtio-ring: move queue_index to vring_virtqueue

2012-09-28T05:35:15Z

Instead of storing the queue index in transport-specific virtio structs, this patch moves them to vring_virtqueue and introduces an helper to get the value. This lets drivers simplify their management and tracing of virtqueues. Signed-off-by: Jason Wang Signed-off-by: Paolo Bonzini Signed-off-by: Rusty Russell

virtio: harsher barriers for rpmsg.

2012-01-12T05:14:42Z

We were cheating with our barriers; using the smp ones rather than the real device ones. That was fine, until rpmsg came along, which is used to talk to a real device (a non-SMP CPU). Unfortunately, just putting back the real barriers (reverting d57ed95d) causes a performance regression on virtio-pci. In particular, Amos reports netbench's TCP_RR over virtio_net CPU utilization increased up to 35% while throughput went down by up to 14%. By comparison, this branch is in the noise. Reference: https://lkml.org/lkml/2011/12/11/22 Signed-off-by: Rusty Russell

virtio: modify vring_init and vring_size to take account of the layout containing *_event_idx

2011-11-02T01:10:59Z

Based on the layout description in the comments, take account of the *_event_idx in functions vring_init and vring_size. Signed-off-by: Wang Sheng-Hui Signed-off-by: Rusty Russell

virtio ring: inline function to check for events

2011-05-30T01:44:14Z

With the new used_event and avail_event and features, both host and guest need similar logic to check whether events are enabled, so it helps to put the common code in the header. Note that Xen has similar logic for notification hold-off in include/xen/interface/io/ring.h with req_event and req_prod corresponding to event_idx + 1 and new_idx respectively. +1 comes from the fact that req_event and req_prod in Xen start at 1, while event index in virtio starts at 0. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell

virtio: event index interface

2011-05-30T01:44:14Z

Define a new feature bit for the guest and host to utilize an event index (like Xen) instead if a flag bit to enable/disable interrupts and kicks. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell