similar to: [PATCH] virtio_net: tidy a couple debug statements

Use the new _ctx virtio API to maintain true length for each buffer. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 91 +++++++++++++++++++++++------------------------- 1 file changed, 44 insertions(+), 47 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 340f737..94f94f3 100644 --- a/drivers/net/virtio_net.c +++

Use the new _ctx virtio API to maintain true length for each buffer. Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 91 +++++++++++++++++++++++------------------------- 1 file changed, 44 insertions(+), 47 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 340f737..94f94f3 100644 --- a/drivers/net/virtio_net.c +++

On 11/28/2013 12:31 AM, Michael S. Tsirkin wrote: > Eric Dumazet noticed that if we encounter an error > when processing a mergeable buffer, we don't > dequeue all of the buffers from this packet, > the result is almost sure to be loss of networking. > > Jason Wang noticed that we also leak a page and that we don't decrement > the rq buf count, so we won't repost

On Wed, Nov 20, 2013 at 05:07:25PM +0800, Jason Wang wrote: > When mergeable buffer were used, we only put the first page buf leave the rest > of buffers in the virt queue. This will cause the driver could not get the > correct head buffer any more. Fix this by dropping the rest of buffers for this > packet. > > The bug was introduced by commit

Pack headroom into ctx, then during XDP set, we could know the size of headroom and copy if needed. This is required for avoiding reset on XDP. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/net/virtio_net.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index

Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers

On Mon, Jul 17, 2017 at 08:43:58PM +0800, Jason Wang wrote: > Pack headroom into ctx, then during XDP set, we could know the size of > headroom and copy if needed. This is required for avoiding reset on > XDP. Not really when XDP is set - it's when buffers are used. virtio-net: pack headroom into ctx for mergeable buffers Pack headroom into ctx - this way when we get a buffer we

On Mon, Jul 17, 2017 at 08:43:58PM +0800, Jason Wang wrote: > Pack headroom into ctx, then during XDP set, we could know the size of > headroom and copy if needed. This is required for avoiding reset on > XDP. Not really when XDP is set - it's when buffers are used. virtio-net: pack headroom into ctx for mergeable buffers Pack headroom into ctx - this way when we get a buffer we

Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag allocators") changed the mergeable receive buffer size from PAGE_SIZE to MTU-size, introducing a single-stream regression for benchmarks with large average packet size. There is no single optimal buffer size for all workloads. For workloads with packet size <= MTU bytes, MTU + virtio-net header-sized buffers

Eric Dumazet noticed that if we encounter an error when processing a mergeable buffer, we don't dequeue all of the buffers from this packet, the result is almost sure to be loss of networking. Jason Wang noticed that we also leak a page and that we don't decrement the rq buf count, so we won't repost buffers (a resource leak). Fix both issues, and also make the logic a bit more

Eric Dumazet noticed that if we encounter an error when processing a mergeable buffer, we don't dequeue all of the buffers from this packet, the result is almost sure to be loss of networking. Jason Wang noticed that we also leak a page and that we don't decrement the rq buf count, so we won't repost buffers (a resource leak). Fix both issues, and also make the logic a bit more

----- ???? ----- > On Wed, Nov 20, 2013 at 05:07:25PM +0800, Jason Wang wrote: > > When mergeable buffer were used, we only put the first page buf leave the > > rest > > of buffers in the virt queue. This will cause the driver could not get the > > correct head buffer any more. Fix this by dropping the rest of buffers for > > this > > packet. > > >

----- ???? ----- > On Wed, Nov 20, 2013 at 05:07:25PM +0800, Jason Wang wrote: > > When mergeable buffer were used, we only put the first page buf leave the > > rest > > of buffers in the virt queue. This will cause the driver could not get the > > correct head buffer any more. Fix this by dropping the rest of buffers for > > this > > packet. > > >

Eric Dumazet noticed that if we encounter an error when processing a mergeable buffer, we don't dequeue all of the buffers from this packet, the result is almost sure to be loss of networking. Jason Wang noticed that we also leak a page and that we don't decrement the rq buf count, so we won't repost buffers (a resource leak). Fix both issues. Cc: Rusty Russell <rusty at

Eric Dumazet noticed that if we encounter an error when processing a mergeable buffer, we don't dequeue all of the buffers from this packet, the result is almost sure to be loss of networking. Jason Wang noticed that we also leak a page and that we don't decrement the rq buf count, so we won't repost buffers (a resource leak). Fix both issues. Cc: Rusty Russell <rusty at

On 01/07/2014 01:25 PM, Michael Dalton wrote: > Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag > allocators") changed the mergeable receive buffer size from PAGE_SIZE to > MTU-size, introducing a single-stream regression for benchmarks with large > average packet size. There is no single optimal buffer size for all > workloads. For workloads

On 01/07/2014 01:25 PM, Michael Dalton wrote: > Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag > allocators") changed the mergeable receive buffer size from PAGE_SIZE to > MTU-size, introducing a single-stream regression for benchmarks with large > average packet size. There is no single optimal buffer size for all > workloads. For workloads

On Mon, Jan 06, 2014 at 09:25:54PM -0800, Michael Dalton wrote: > Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag > allocators") changed the mergeable receive buffer size from PAGE_SIZE to > MTU-size, introducing a single-stream regression for benchmarks with large > average packet size. There is no single optimal buffer size for all >

On Mon, Jan 06, 2014 at 09:25:54PM -0800, Michael Dalton wrote: > Commit 2613af0ed18a ("virtio_net: migrate mergeable rx buffers to page frag > allocators") changed the mergeable receive buffer size from PAGE_SIZE to > MTU-size, introducing a single-stream regression for benchmarks with large > average packet size. There is no single optimal buffer size for all >

On Mon, Oct 28, 2013 at 10:44 PM, Michael Dalton <mwdalton at google.com> wrote: > The virtio_net driver's mergeable receive buffer allocator > uses 4KB packet buffers. For MTU-sized traffic, SKB truesize > is > 4KB but only ~1500 bytes of the buffer is used to store > packet data, reducing the effective TCP window size > substantially. This patch addresses the