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

zhenwei pi
2023-05-17T05:01:00Z

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