Re: Re: Re: [PATCH v2 0/2] virtio: abstract virtqueue related methods

[zhenwei pi]

On 5/17/23 11:57, Michael S. Tsirkin wrote:
> On Wed, May 17, 2023 at 11:51:03AM +0800, zhenwei pi wrote:
> > On 5/17/23 11:46, Michael S. Tsirkin wrote:
> > > On Wed, May 17, 2023 at 10:54:22AM +0800, zhenwei pi wrote:
> > > > v1 -> v2:
> > > > - Suggested by MST, use fast path for vring based performance
> > > > sensitive API.
> > > > - Reduce changes in tools/virtio.
> > > >
> > > > Add test result(no obvious change):
> > > > Before:
> > > > time ./vringh_test --parallel
> > > > Using CPUS 0 and 191
> > > > Guest: notified 10036893, pinged 68278
> > > > Host: notified 68278, pinged 3093532
> > > >
> > > > real	0m14.463s
> > > > user	0m6.437s
> > > > sys	0m8.010s
> > > >
> > > > After:
> > > > time ./vringh_test --parallel
> > > > Using CPUS 0 and 191
> > > > Guest: notified 10036709, pinged 68347
> > > > Host: notified 68347, pinged 3085292
> > > >
> > > > real	0m14.196s
> > > > user	0m6.289s
> > > > sys	0m7.885s
> > > >
> > > > v1:
> > > > Hi,
> > > >
> > > > 3 weeks ago, I posted a proposal 'Virtio Over Fabrics':
> > > > https://lists.oasis-open.org/archives/virtio-comment/202304/msg00442.html
> > > >
> > > > Jason and Stefan pointed out that a non-vring based virtqueue has a
> > > > chance to overwrite virtqueue instead of using vring virtqueue.
> > > >
> > > > Then I try to abstract virtqueue related methods in this series, the
> > > > details changes see the comment of patch 'virtio: abstract virtqueue related methods'.
> > > >
> > > > Something is still remained:
> > > > - __virtqueue_break/__virtqueue_unbreak is supposed to use by internal
> > > >     virtio core, I'd like to rename them to vring_virtqueue_break
> > > >     /vring_virtqueue_unbreak. Is this reasonable?
> > >
> > > Why? These just set a flag?
> >
> > Rename '__virtqueue_break' to 'vring_virtqueue_break', to make symbols
> > exported from virtio_ring.ko have unified prefix 'vring_virtqueue_xxx'.
>
> I just do not see why you need these callbacks at all.

I use these callbacks for break/unbreak device like:
static inline void virtio_break_device(struct virtio_device *dev)
{
	struct virtqueue *vq;

	spin_lock(&dev->vqs_list_lock);
	list_for_each_entry(vq, &dev->vqs, list) {
		vq->__break(vq);
	}
	spin_unlock(&dev->vqs_list_lock);
}

> > > > - virtqueue_get_desc_addr/virtqueue_get_avail_addr/virtqueue_get_used_addr
> > > >     /virtqueue_get_vring is vring specific, I'd like to rename them like
> > > >     vring_virtqueue_get_desc_addr. Is this reasonable?
> > > > - there are still some functions in virtio_ring.c with prefix *virtqueue*,
> > > >     for example 'virtqueue_add_split', just keep it or rename it to
> > > >     'vring_virtqueue_add_split'?
> > > > zhenwei pi (2):
> > > >     virtio: abstract virtqueue related methods
> > > >     tools/virtio: implement virtqueue in test
> > > >
> > > >    drivers/virtio/virtio_ring.c | 285 +++++-----------------
> > > >    include/linux/virtio.h       | 441 +++++++++++++++++++++++++++++++----
> > > >    include/linux/virtio_ring.h  |  26 +++
> > > >    tools/virtio/linux/virtio.h  | 355 +++++++++++++++++++++++++---
> > > >    4 files changed, 807 insertions(+), 300 deletions(-)
> > > >
> > > > --
> > > > 2.20.1
> >
> > --
> > zhenwei pi

--
zhenwei pi