similar to: [PATCH net-next] vhost_net: conditionally enable tx polling

On 2017?11?01? 00:36, Michael S. Tsirkin wrote: > On Tue, Oct 31, 2017 at 06:27:20PM +0800, Jason Wang wrote: >> We always poll tx for socket, this is sub optimal since: >> >> - we only want to be notified when sndbuf is available >> - this will slightly increase the waitqueue traversing time and more >> important, vhost could not benefit from commit >>

On 2017?11?01? 00:36, Michael S. Tsirkin wrote: > On Tue, Oct 31, 2017 at 06:27:20PM +0800, Jason Wang wrote: >> We always poll tx for socket, this is sub optimal since: >> >> - we only want to be notified when sndbuf is available >> - this will slightly increase the waitqueue traversing time and more >> important, vhost could not benefit from commit >>

On Tue, Oct 31, 2017 at 06:27:20PM +0800, Jason Wang wrote: > We always poll tx for socket, this is sub optimal since: > > - we only want to be notified when sndbuf is available > - this will slightly increase the waitqueue traversing time and more > important, vhost could not benefit from commit > commit 9e641bdcfa4e > ("net-tun: restructure tun_do_read for better

On Wed, Nov 01, 2017 at 08:51:36PM +0800, Jason Wang wrote: > > > On 2017?11?01? 00:36, Michael S. Tsirkin wrote: > > On Tue, Oct 31, 2017 at 06:27:20PM +0800, Jason Wang wrote: > > > We always poll tx for socket, this is sub optimal since: > > > > > > - we only want to be notified when sndbuf is available > > > - this will slightly increase

Hi: This small series try to fix several bugs of ptr_ring usage in vhost_net. Please review. Thanks Alexander Potapenko (1): vhost_net: initialize rx_ring in vhost_net_open() Jason Wang (2): vhost_net: keep private_data and rx_ring synced vhost_net: examine pointer types during un-producing drivers/net/tun.c | 3 ++- drivers/vhost/net.c | 8 +++++--- include/linux/if_tun.h | 4

This is an update version of last version to fix the handling of polling errors in vhost/vhost_net. Currently, vhost and vhost_net ignore polling errors which can lead kernel crashing when it tries to remove itself from waitqueue after the polling failure. Fix this by checking the poll->wqh before the removing and report an error when meet polling errors. Changes from v2: - check poll->wqh

This is an update version of last version to fix the handling of polling errors in vhost/vhost_net. Currently, vhost and vhost_net ignore polling errors which can lead kernel crashing when it tries to remove itself from waitqueue after the polling failure. Fix this by checking the poll->wqh before the removing and report an error when meet polling errors. Changes from v2: - check poll->wqh

We always poll tx for socket, this is sub optimal since this will slightly increase the waitqueue traversing time and more important, vhost could not benefit from commit 9e641bdcfa4e ("net-tun: restructure tun_do_read for better sleep/wakeup efficiency") even if we've stopped rx polling during handle_rx(), tx poll were still left in the waitqueue. Pktgen from a remote host to VM

We always poll tx for socket, this is sub optimal since this will slightly increase the waitqueue traversing time and more important, vhost could not benefit from commit 9e641bdcfa4e ("net-tun: restructure tun_do_read for better sleep/wakeup efficiency") even if we've stopped rx polling during handle_rx(), tx poll were still left in the waitqueue. Pktgen from a remote host to VM

Asias He (4): vhost-net: Always access vq->private_data under vq mutex vhost-test: Always access vq->private_data under vq mutex vhost-scsi: Always access vq->private_data under vq mutex vhost: Remove custom vhost rcu usage drivers/vhost/net.c | 37 ++++++++++++++++--------------------- drivers/vhost/scsi.c | 17 ++++++----------- drivers/vhost/test.c | 20

Asias He (4): vhost-net: Always access vq->private_data under vq mutex vhost-test: Always access vq->private_data under vq mutex vhost-scsi: Always access vq->private_data under vq mutex vhost: Remove custom vhost rcu usage drivers/vhost/net.c | 37 ++++++++++++++++--------------------- drivers/vhost/scsi.c | 17 ++++++----------- drivers/vhost/test.c | 20

Hi: This series tries to optimize vhost_net polling at two points: - Stop rx polling for reduicng the unnecessary wakeups during handle_rx(). - Conditonally enable tx polling for reducing the unnecessary traversing and spinlock touching. Test shows about 17% improvement on rx pps. Please review Changes from V1: - use vhost_net_disable_vq()/vhost_net_enable_vq() instead of open coding. -

Hi: This series tries to optimize vhost_net polling at two points: - Stop rx polling for reduicng the unnecessary wakeups during handle_rx(). - Conditonally enable tx polling for reducing the unnecessary traversing and spinlock touching. Test shows about 17% improvement on rx pps. Please review Changes from V1: - use vhost_net_disable_vq()/vhost_net_enable_vq() instead of open coding. -

On Wed, Jun 01, 2016 at 01:56:34AM -0400, Jason Wang wrote: > We always poll tx for socket, this is sub optimal since: > > - it will be only used when we exceed the sndbuf of the socket. > - since we use two independent polls for tx and vq, this will slightly > increase the waitqueue traversing time and more important, vhost > could not benefit from commit >

On Wed, Jun 01, 2016 at 01:56:34AM -0400, Jason Wang wrote: > We always poll tx for socket, this is sub optimal since: > > - it will be only used when we exceed the sndbuf of the socket. > - since we use two independent polls for tx and vq, this will slightly > increase the waitqueue traversing time and more important, vhost > could not benefit from commit >

Hi: This series tries to optimize vhost_net polling at two points: - Stop rx polling for reduicng the unnecessary wakeups during handle_rx(). - Conditonally enable tx polling for reducing the unnecessary traversing and spinlock touching. Test shows about 17% improvement on rx pps. Please review Changes from V2: - Don't enable rx vq if we meet an err or rx vq is empty Changes from V1:

Hi: This series tries to optimize vhost_net polling at two points: - Stop rx polling for reduicng the unnecessary wakeups during handle_rx(). - Conditonally enable tx polling for reducing the unnecessary traversing and spinlock touching. Test shows about 17% improvement on rx pps. Please review Changes from V2: - Don't enable rx vq if we meet an err or rx vq is empty Changes from V1:

Hi! Recently I have been investigating some strange migration problems on s390x. It turned out under certain circumstances vhost_net corrupts avail.idx by using wrong endianness. I managed to track the problem down (I'm pretty sure). It boils down to the following. When stopping vhost userspace (QEMU) calls vhost_net_set_backend with the fd argument set to -1, this leads to is_le being

Hi! Recently I have been investigating some strange migration problems on s390x. It turned out under certain circumstances vhost_net corrupts avail.idx by using wrong endianness. I managed to track the problem down (I'm pretty sure). It boils down to the following. When stopping vhost userspace (QEMU) calls vhost_net_set_backend with the fd argument set to -1, this leads to is_le being

On Mon, May 30, 2016 at 02:47:54AM -0400, Jason Wang wrote: > We always poll tx for socket, this is sub optimal since: > > - it will be only used when we exceed the sndbuf of the socket. > - since we use two independent polls for tx and vq, this will slightly > increase the waitqueue traversing time and more important, vhost > could not benefit from commit >