similar to: [PATCH] vhost: fix signed/unsigned comparison

We used to implement the work flushing through tracking queued seq, done seq, and the number of flushing. This patch simplify this by just implement work flushing through another kind of vhost work with completion. This will be used by lockless enqueuing patch. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 53

We used to implement the work flushing through tracking queued seq, done seq, and the number of flushing. This patch simplify this by just implement work flushing through another kind of vhost work with completion. This will be used by lockless enqueuing patch. Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 53

Since 2.6.36-rc1, non-root users of vhost-net fail to attach if they are in any cgroups. This is a regression, and libvirt actually uses this functionality, as it runs qemu with reduced priveledges. The bug is that when qemu uses vhost, vhost wants to attach its thread to all cgroups that qemu has. But we got the API backwards, so a non-priveledged process (qemu) tried to control the priveledged

Since 2.6.36-rc1, non-root users of vhost-net fail to attach if they are in any cgroups. This is a regression, and libvirt actually uses this functionality, as it runs qemu with reduced priveledges. The bug is that when qemu uses vhost, vhost wants to attach its thread to all cgroups that qemu has. But we got the API backwards, so a non-priveledged process (qemu) tried to control the priveledged

I saw WARN_ON(!list_empty(&dev->work_list)) trigger so our custom flush is not as airtight as need be. This patch switches to a simple atomic counter + srcu instead of the custom locked queue + flush implementation. This will slow down the setup ioctls, which should not matter - it's slow path anyway. We use the expedited flush to at least make sure it has a sane time bound. Works

I saw WARN_ON(!list_empty(&dev->work_list)) trigger so our custom flush is not as airtight as need be. This patch switches to a simple atomic counter + srcu instead of the custom locked queue + flush implementation. This will slow down the setup ioctls, which should not matter - it's slow path anyway. We use the expedited flush to at least make sure it has a sane time bound. Works

We use spinlock to synchronize the work list now which may cause unnecessary contentions. So this patch switch to use llist to remove this contention. Pktgen tests shows about 5% improvement: Before: ~1300000 pps After: ~1370000 pps Signed-off-by: Jason Wang <jasowang at redhat.com> --- drivers/vhost/vhost.c | 52 +++++++++++++++++++++++++-------------------------- drivers/vhost/vhost.h |

Hi Jason, Overall patches look good. Just one doubt I have is below: > > We use spinlock to synchronize the work list now which may cause > unnecessary contentions. So this patch switch to use llist to remove > this contention. Pktgen tests shows about 5% improvement: > > Before: > ~1300000 pps > After: > ~1370000 pps > > Signed-off-by: Jason Wang <jasowang

Hi Jason, Overall patches look good. Just one doubt I have is below: > > We use spinlock to synchronize the work list now which may cause > unnecessary contentions. So this patch switch to use llist to remove > this contention. Pktgen tests shows about 5% improvement: > > Before: > ~1300000 pps > After: > ~1370000 pps > > Signed-off-by: Jason Wang <jasowang

On Sun, Jul 07, 2013 at 02:37:10PM +0300, Michael S. Tsirkin wrote: > On Mon, May 06, 2013 at 08:10:03PM +0800, Asias He wrote: > > On Mon, May 06, 2013 at 01:03:42PM +0300, Michael S. Tsirkin wrote: > > > On Mon, May 06, 2013 at 04:38:21PM +0800, Asias He wrote: > > > > Currently, vhost-net and vhost-scsi are sharing the vhost core code. > > > > However,

On Mon, May 06, 2013 at 08:10:03PM +0800, Asias He wrote: > On Mon, May 06, 2013 at 01:03:42PM +0300, Michael S. Tsirkin wrote: > > On Mon, May 06, 2013 at 04:38:21PM +0800, Asias He wrote: > > > Currently, vhost-net and vhost-scsi are sharing the vhost core code. > > > However, vhost-scsi shares the code by including the vhost.c file > > > directly. > >

On Mon, May 06, 2013 at 08:10:03PM +0800, Asias He wrote: > On Mon, May 06, 2013 at 01:03:42PM +0300, Michael S. Tsirkin wrote: > > On Mon, May 06, 2013 at 04:38:21PM +0800, Asias He wrote: > > > Currently, vhost-net and vhost-scsi are sharing the vhost core code. > > > However, vhost-scsi shares the code by including the vhost.c file > > > directly. > >

On Sun, Aug 10, 2014 at 11:30:35AM +0300, Razya Ladelsky wrote: > From: Razya Ladelsky <razya at il.ibm.com> > Date: Thu, 31 Jul 2014 09:47:20 +0300 > Subject: [PATCH] vhost: Add polling mode > > When vhost is waiting for buffers from the guest driver (e.g., more packets to > send in vhost-net's transmit queue), it normally goes to sleep and waits for the > guest to

On Sun, Aug 10, 2014 at 11:30:35AM +0300, Razya Ladelsky wrote: > From: Razya Ladelsky <razya at il.ibm.com> > Date: Thu, 31 Jul 2014 09:47:20 +0300 > Subject: [PATCH] vhost: Add polling mode > > When vhost is waiting for buffers from the guest driver (e.g., more packets to > send in vhost-net's transmit queue), it normally goes to sleep and waits for the > guest to

Add some kind of vblank workers. The interface is similar to regular delayed works, and is mostly based off kthread_work. It allows for scheduling delayed works that execute once a particular vblank sequence has passed. It also allows for accurate flushing of scheduled vblank works - in that flushing waits for both the vblank sequence and job execution to complete, or for the work to get cancelled

Add some kind of vblank workers. The interface is similar to regular delayed works, and is mostly based off kthread_work. It allows for scheduling delayed works that execute once a particular vblank sequence has passed. It also allows for accurate flushing of scheduled vblank works - in that flushing waits for both the vblank sequence and job execution to complete, or for the work to get cancelled

The patch (7235acdb1) changed the way of the work flushing in which the queued seq, done seq, and the flushing are not used anymore. Then remove them now. Fixes: 7235acdb1 ("vhost: simplify work flushing") Cc: Jason Wang <jasowang at redhat.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> --- drivers/vhost/vhost.c | 1 - drivers/vhost/vhost.h | 4 ---- 2

From: Razya Ladelsky <razya at il.ibm.com> Date: Thu, 31 Jul 2014 09:47:20 +0300 Subject: [PATCH] vhost: Add polling mode When vhost is waiting for buffers from the guest driver (e.g., more packets to send in vhost-net's transmit queue), it normally goes to sleep and waits for the guest to "kick" it. This kick involves a PIO in the guest, and therefore an exit (and possibly

From: Razya Ladelsky <razya at il.ibm.com> Date: Thu, 31 Jul 2014 09:47:20 +0300 Subject: [PATCH] vhost: Add polling mode When vhost is waiting for buffers from the guest driver (e.g., more packets to send in vhost-net's transmit queue), it normally goes to sleep and waits for the guest to "kick" it. This kick involves a PIO in the guest, and therefore an exit (and possibly

The patch (7235acdb1) changed the way of the work flushing in which the queued seq, done seq, and the flushing are not used anymore. Then remove them now. Fixes: 7235acdb1 ("vhost: simplify work flushing") Cc: Jason Wang <jasowang at redhat.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue at gmail.com> Acked-by: Jason Wang <jasowang at redhat.com> ---