Asias He as...@redhat.com writes:
I forgot about the cool hack which MST put in to defer event updates
using disable_cb/enable_cb.
Hmm, are you talking about virtqueue_enable_cb_delayed()?
Just the fact that virtqueue_disable_cb() prevents updates of
used_index, and then we do the update in
On 09/28/2012 02:08 PM, Rusty Russell wrote:
Asias He as...@redhat.com writes:
I forgot about the cool hack which MST put in to defer event updates
using disable_cb/enable_cb.
Hmm, are you talking about virtqueue_enable_cb_delayed()?
Just the fact that virtqueue_disable_cb() prevents
On Thu, Sep 27, 2012 at 09:40:03AM +0930, Rusty Russell wrote:
I forgot about the cool hack which MST put in to defer event updates
using disable_cb/enable_cb.
I considered sticking some invalid value
in event index on disable but in my testing it did not seem to
give any gain, and knowing
Thinking about Sasha's patches, we can reduce ring usage
for virtio net small packets dramatically if we put
virtio net header inline with the data.
This can be done for free in case guest net stack allocated
extra head room for the packet, and I don't see
why would this have any downsides.
Even
It's sometimes necessary to query ring capacity after dequeueing a
buffer. Add an API for this.
Signed-off-by: Michael S. Tsirkin m...@redhat.com
---
drivers/virtio/virtio_ring.c | 19 +++
include/linux/virtio.h | 2 ++
2 files changed, 21 insertions(+)
diff --git
Capacity math on ring full is wrong: we are
looking at num_sg but that might be optimistic
because of indirect buffer use.
The implementation also penalizes fast path
with extra memory accesses for the benefit of
ring full condition handling which is slow path.
It's easy to query ring capacity
For small packets we can simplify xmit processing
by linearizing buffers with the header:
most packets seem to have enough head room
we can use for this purpose.
Since existing hypervisors require that header
is the first s/g element, we need a feature bit
for this.
Signed-off-by: Michael S.
Old qemu versions required that 1st s/g entry is the header.
My recent patchset titled virtio-net: iovec handling cleanup
removed this limitation but a feature
bit is needed so guests know it's safe to lay out
header differently.
This patch applies on top and adds such a feature bit.
virtio net
On (Tue) 25 Sep 2012 [15:47:14], sjur.brandel...@stericsson.com wrote:
From: Sjur Brændeland sjur.brandel...@stericsson.com
I thought rebasing rproc_serial to linux-next was going to be trivial.
But when starting the merge I realized that I had to refactor the
the patches from Masami
