From: Maxime Coquelin <maxime.coquelin@redhat.com>
To: "Hu, Jiayu" <jiayu.hu@intel.com>,
"Jiang, Cheng1" <cheng1.jiang@intel.com>,
"Xia, Chenbo" <chenbo.xia@intel.com>,
Thomas Monjalon <thomas@monjalon.net>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
"Yang, YvonneX" <yvonnex.yang@intel.com>,
"Wang, Yinan" <yinan.wang@intel.com>,
"stable@dpdk.org" <stable@dpdk.org>
Subject: Re: [dpdk-dev] [PATCH] examples/vhost: fix ioat ring space in callbacks
Date: Tue, 13 Apr 2021 10:50:55 +0200 [thread overview]
Message-ID: <4f2e0296-4c68-197b-ad07-6b43e5e2da38@redhat.com> (raw)
In-Reply-To: <13e28ecd418142fda75873f7a0bc2b4d@intel.com>
On 4/7/21 9:54 AM, Hu, Jiayu wrote:
> Hi Maxime,
>
>> -----Original Message-----
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>> Sent: Wednesday, April 7, 2021 3:48 PM
>> To: Jiang, Cheng1 <cheng1.jiang@intel.com>; Xia, Chenbo
>> <chenbo.xia@intel.com>; Thomas Monjalon <thomas@monjalon.net>
>> Cc: dev@dpdk.org; Hu, Jiayu <jiayu.hu@intel.com>; Yang, YvonneX
>> <yvonnex.yang@intel.com>; Wang, Yinan <yinan.wang@intel.com>;
>> stable@dpdk.org
>> Subject: Re: [PATCH] examples/vhost: fix ioat ring space in callbacks
>>
>>
>>
>> On 3/17/21 6:40 AM, Cheng Jiang wrote:
>>> We use ioat ring space for determining if ioat callbacks can enqueue a
>>> packet to ioat device. But there is one slot can't be used in ioat
>>> ring due to the ioat driver design, so we need to reduce one slot in
>>> ioat ring to prevent ring size mismatch in ioat callbacks.
>>>
>>> Fixes: 2aa47e94bfb2 ("examples/vhost: add ioat ring space count and
>> check")
>>> Cc: stable@dpdk.org
>>>
>>> Signed-off-by: Cheng Jiang <Cheng1.jiang@intel.com>
>>> ---
>>> examples/vhost/ioat.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/examples/vhost/ioat.c b/examples/vhost/ioat.c
>>> index 60b73be93..9cb5e0d50 100644
>>> --- a/examples/vhost/ioat.c
>>> +++ b/examples/vhost/ioat.c
>>> @@ -113,7 +113,7 @@ open_ioat(const char *value)
>>> goto out;
>>> }
>>> rte_rawdev_start(dev_id);
>>> - cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE;
>>> + cb_tracker[dev_id].ioat_space = IOAT_RING_SIZE - 1;
>>
>> That really comforts me in thinking we need a generic abstraction for
>> DMA devices. How is the application developer supposed to know that
>> the DMA driver has such weird limitations?
>>
>> Can the driver be fixed to have a proper behavior?
>
> Here is the patch of providing capacity check API for DMA:
> http://patches.dpdk.org/project/dpdk/patch/20210318182042.43658-6-bruce.richardson@intel.com/
OK, thanks for the pointer.
While this new API is being reviewed, and for LTS, let's pick your
patch. As soon as Bruce patch is merged, please send a new patch on top
to make use of this API.
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Thanks,
Maxime
> Thanks,
> Jiayu
>>
>>> dma_info->nr++;
>>> i++;
>>> }
>>>
>
next prev parent reply other threads:[~2021-04-13 8:51 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-17 5:40 Cheng Jiang
2021-03-17 6:58 ` Hu, Jiayu
2021-04-07 7:47 ` Maxime Coquelin
2021-04-07 7:54 ` Hu, Jiayu
2021-04-13 8:50 ` Maxime Coquelin [this message]
2021-04-13 9:55 ` Jiang, Cheng1
2021-04-07 8:26 ` Thomas Monjalon
2021-04-07 8:43 ` Thomas Monjalon
2021-04-18 15:10 ` Liang Ma
2021-04-07 8:48 ` Maxime Coquelin
2021-04-28 2:09 ` Xia, Chenbo
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=4f2e0296-4c68-197b-ad07-6b43e5e2da38@redhat.com \
--to=maxime.coquelin@redhat.com \
--cc=chenbo.xia@intel.com \
--cc=cheng1.jiang@intel.com \
--cc=dev@dpdk.org \
--cc=jiayu.hu@intel.com \
--cc=stable@dpdk.org \
--cc=thomas@monjalon.net \
--cc=yinan.wang@intel.com \
--cc=yvonnex.yang@intel.com \
/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).