kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Stefano Garzarella <sgarzare@redhat.com>
To: Arseny Krasnov <arseny.krasnov@kaspersky.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Jorgen Hansen <jhansen@vmware.com>,
	Colin Ian King <colin.king@canonical.com>,
	Andra Paraschiv <andraprs@amazon.com>,
	Norbert Slusarek <nslusarek@gmx.net>,
	Alexander Popov <alex.popov@linux.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	"virtualization@lists.linux-foundation.org" 
	<virtualization@lists.linux-foundation.org>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"stsp2@yandex.ru" <stsp2@yandex.ru>,
	"oxffffaa@gmail.com" <oxffffaa@gmail.com>
Subject: Re: [RFC PATCH v8 00/19] virtio/vsock: introduce SOCK_SEQPACKET support
Date: Thu, 22 Apr 2021 12:48:13 +0200	[thread overview]
Message-ID: <20210422104813.e2p4wzuk2ahw7af7@steredhat> (raw)
In-Reply-To: <bc649d1b-80d8-835c-6f47-8a7d402dd0b7@kaspersky.com>

On Thu, Apr 22, 2021 at 01:29:54PM +0300, Arseny Krasnov wrote:
>
>On 22.04.2021 13:02, Stefano Garzarella wrote:
>> On Thu, Apr 22, 2021 at 12:40:17PM +0300, Arseny Krasnov wrote:
>>> On 22.04.2021 11:46, Stefano Garzarella wrote:
>>>> On Wed, Apr 21, 2021 at 06:06:28PM +0300, Arseny Krasnov wrote:
>>>>> Thank You, i'll prepare next version. Main question is: does this
>>>>> approach(no SEQ_BEGIN, SEQ_END, 'msg_len' and 'msg_id') considered
>>>>> good? In this case it will be easier to prepare final version, because
>>>>> is smaller and more simple than previous logic. Also patch to spec
>>>>> will be smaller.
>>>> Yes, it's definitely much better than before.
>>>>
>>>> The only problem I see is that we add some overhead per fragment
>>>> (header). We could solve that with the mergeable buffers that Jiang is
>>>> considering for DGRAM.
>>> If we are talking about receive, i think, i can reuse merge logic for
>> Yep, for TX the guest can potentially enqueue a big buffer.
>> Maybe it's still worth keeping a maximum size and fragmenting as we do
>> now.
>>
>>> stream sockets, the only difference is that buffers are mergeable
>>> until previous EOR(e.g. previous message) bit is found in rx queue.
>>>
>> I got a little lost.
>> Can you elaborate more?
>
>I'm talking about 'virtio_transport_recv_enqueue()': it tries to copy
>
>data of new packet to buffer of tail packet in rx queue. In case of
>
>SEQPACKET i can reuse it, just adding logic that check EOR bit of
>
>tail packet.

This might be a good idea.
It doesn't save us the transmitted header though, but at least it saves 
us from queuing it.
Even if with SEQPACKET I don't expect small packets, since it's the 
driver that divides them and I think it does everything to use the 
maximum available.

Instead the mergeable buffers I was referring to are based on the 
virito-net feature VIRTIO_NET_F_MRG_RXBUF.
Jiang is investigating whether we can reuse them for DGRAM.

Thanks,
Stefano


  reply	other threads:[~2021-04-22 10:48 UTC|newest]

Thread overview: 43+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-13 12:39 [RFC PATCH v8 00/19] virtio/vsock: introduce SOCK_SEQPACKET support Arseny Krasnov
2021-04-13 12:41 ` [RFC PATCH v8 01/19] af_vsock: update functions for connectible socket Arseny Krasnov
2021-04-13 12:42 ` [RFC PATCH v8 02/19] af_vsock: separate wait data loop Arseny Krasnov
2021-04-13 12:42 ` [RFC PATCH v8 03/19] af_vsock: separate receive " Arseny Krasnov
2021-04-13 12:42 ` [RFC PATCH v8 04/19] af_vsock: implement SEQPACKET receive loop Arseny Krasnov
2021-04-21  8:37   ` Stefano Garzarella
2021-04-21 14:47     ` Arseny Krasnov
2021-04-13 12:43 ` [RFC PATCH v8 05/19] af_vsock: implement send logic for SEQPACKET Arseny Krasnov
2021-04-13 12:43 ` [RFC PATCH v8 06/19] af_vsock: rest of SEQPACKET support Arseny Krasnov
2021-04-13 12:43 ` [RFC PATCH v8 07/19] af_vsock: update comments for stream sockets Arseny Krasnov
2021-04-13 12:43 ` [RFC PATCH v8 08/19] virtio/vsock: set packet's type in virtio_transport_send_pkt_info() Arseny Krasnov
2021-04-13 12:44 ` [RFC PATCH v8 09/19] virtio/vsock: simplify credit update function API Arseny Krasnov
2021-04-13 12:44 ` [RFC PATCH v8 10/19] virtio/vsock: defines and constants for SEQPACKET Arseny Krasnov
2021-04-13 12:44 ` [RFC PATCH v8 11/19] virtio/vsock: dequeue callback for SOCK_SEQPACKET Arseny Krasnov
2021-04-14  5:21   ` Arseny Krasnov
2021-04-21  8:56   ` Stefano Garzarella
2021-04-21 14:49     ` Arseny Krasnov
2021-04-13 12:45 ` [RFC PATCH v8 12/19] virtio/vsock: add SEQPACKET receive logic Arseny Krasnov
2021-04-13 12:45 ` [RFC PATCH v8 13/19] virtio/vsock: rest of SOCK_SEQPACKET support Arseny Krasnov
2021-04-21  9:12   ` Stefano Garzarella
2021-04-21 14:50     ` Arseny Krasnov
2021-04-13 12:45 ` [RFC PATCH v8 14/19] virtio/vsock: enable SEQPACKET for transport Arseny Krasnov
2021-04-21  9:22   ` Stefano Garzarella
2021-04-13 12:46 ` [RFC PATCH v8 15/19] vhost/vsock: " Arseny Krasnov
2021-04-21  9:31   ` Stefano Garzarella
2021-04-13 12:46 ` [RFC PATCH v8 16/19] vsock/loopback: " Arseny Krasnov
2021-04-21  9:34   ` Stefano Garzarella
2021-04-13 12:46 ` [RFC PATCH v8 17/19] vsock_test: add SOCK_SEQPACKET tests Arseny Krasnov
2021-04-21  9:35   ` Stefano Garzarella
2021-04-21 15:00     ` Arseny Krasnov
2021-04-13 12:47 ` [RFC PATCH v8 18/19] virtio/vsock: update trace event for SEQPACKET Arseny Krasnov
2021-04-13 12:47 ` [RFC PATCH v8 19/19] af_vsock: serialize writes to shared socket Arseny Krasnov
2021-04-14 10:51   ` Arseny Krasnov
2021-04-21  9:38     ` Stefano Garzarella
2021-04-21 15:02       ` Arseny Krasnov
2021-04-21  9:52 ` [RFC PATCH v8 00/19] virtio/vsock: introduce SOCK_SEQPACKET support Stefano Garzarella
2021-04-21 15:06   ` Arseny Krasnov
2021-04-22  8:46     ` Stefano Garzarella
2021-04-22  9:40       ` Arseny Krasnov
2021-04-22 10:02         ` Stefano Garzarella
2021-04-22 10:29           ` Arseny Krasnov
2021-04-22 10:48             ` Stefano Garzarella [this message]
2021-04-22 11:41               ` Arseny Krasnov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210422104813.e2p4wzuk2ahw7af7@steredhat \
    --to=sgarzare@redhat.com \
    --cc=alex.popov@linux.com \
    --cc=andraprs@amazon.com \
    --cc=arseny.krasnov@kaspersky.com \
    --cc=colin.king@canonical.com \
    --cc=davem@davemloft.net \
    --cc=jasowang@redhat.com \
    --cc=jhansen@vmware.com \
    --cc=kuba@kernel.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=nslusarek@gmx.net \
    --cc=oxffffaa@gmail.com \
    --cc=stefanha@redhat.com \
    --cc=stsp2@yandex.ru \
    --cc=virtualization@lists.linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).