From: Ferruh Yigit <ferruh.yigit@intel.com>
To: "Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>,
"Shahaf Shuler" <shahafs@mellanox.com>,
"Yongseok Koh" <yskoh@mellanox.com>
Cc: Adrien Mazarguil <adrien.mazarguil@6wind.com>,
"dev@dpdk.org" <dev@dpdk.org>,
"stable@dpdk.org" <stable@dpdk.org>
Subject: Re: [dpdk-stable] [PATCH] net/mlx5: fix calculating TSO inline size
Date: Fri, 15 Sep 2017 09:39:04 +0100 [thread overview]
Message-ID: <c6ac2fe7-735e-db5a-3ac1-9d63ccbdc14c@intel.com> (raw)
In-Reply-To: <20170913072606.GA29920@autoinstall.dev.6wind.com>
On 9/13/2017 8:26 AM, Nélio Laranjeiro wrote:
> On Wed, Sep 13, 2017 at 05:05:14AM +0000, Shahaf Shuler wrote:
>> Tuesday, September 12, 2017 9:34 PM, Nélio Laranjeiro:
>>>> On Sep 12, 2017, at 12:24 AM, Nélio Laranjeiro
>>>>>> Is not it dangerous to assume inl will always be 4 bytes long? Why
>>>>>> not writing the real value instead?
>>>>> That was for readability of the code and uint32_t will be always
>>>>> 4bytes. But for better readability, it should be 'inline_header'
>>>>> instead of 'inl' though. I'm also okay with using "4" as well. Which way do
>>> you prefer?
>>>>
>>>> I agree on both, I was not clear enough to explain my thought, if for
>>>> some reason the inl moves from uint32_t to uint16_t without touching
>>>> the sizeof later, it will cause an issue.
>>>
>>> I tried to change the sizeof but I found that there are more "sizeof(inl)" in the
>>> following lines. Changing all the sizeof would be beyond the scope of this
>>> patch. So, how about leaving it as is for consistency?
>>
>> The inline segment format is not expected to change so easily. It is parsed
>> by the HW and HW maintains backward compatibility for all of the WQE
>> structures.
>
> We are not talking here about the hardware behavior but about wrong ways to
> define hardware values which should be used trough define and not by size of
> variable which can be wrongly modified.
> If the hardware inline_header size of 4, it should be defined as is.
>
> I won't block this patch as it is not the single place where this sizeof is
> used, but it should be replaced as soon as possible by a define to avoid wrong
> behaviors in the future.
>
> Acked-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
Applied to dpdk-next-net/master, thanks.
prev parent reply other threads:[~2017-09-15 8:39 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-31 16:27 Yongseok Koh
2017-09-04 14:01 ` Nélio Laranjeiro
2017-09-11 22:17 ` Yongseok Koh
2017-09-12 7:24 ` Nélio Laranjeiro
2017-09-12 18:34 ` Yongseok Koh
2017-09-13 5:05 ` Shahaf Shuler
2017-09-13 7:26 ` Nélio Laranjeiro
2017-09-15 8:39 ` Ferruh Yigit [this message]
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=c6ac2fe7-735e-db5a-3ac1-9d63ccbdc14c@intel.com \
--to=ferruh.yigit@intel.com \
--cc=adrien.mazarguil@6wind.com \
--cc=dev@dpdk.org \
--cc=nelio.laranjeiro@6wind.com \
--cc=shahafs@mellanox.com \
--cc=stable@dpdk.org \
--cc=yskoh@mellanox.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).