DPDK patches and discussions
 help / color / mirror / Atom feed
From: "Wiles, Keith" <keith.wiles@intel.com>
To: "Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>
Cc: "Morten Brørup" <mb@smartsharesystems.com>,
	"Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
	"Richardson, Bruce" <bruce.richardson@intel.com>,
	DPDK <dev@dpdk.org>, "Olivier Matz" <olivier.matz@6wind.com>,
	"Lu, Wenzhuo" <wenzhuo.lu@intel.com>,
	"Adrien Mazarguil" <adrien.mazarguil@6wind.com>
Subject: Re: [dpdk-dev] [PATCH] net: introduce big and little endian types
Date: Tue, 6 Dec 2016 16:31:41 +0000	[thread overview]
Message-ID: <D1B9E864-EE9F-424D-8EE4-D62AC3B4FE90@intel.com> (raw)
In-Reply-To: <20161206162807.GS21794@autoinstall.dev.6wind.com>


> On Dec 6, 2016, at 10:28 AM, Nélio Laranjeiro <nelio.laranjeiro@6wind.com> wrote:
> 
> Hi all,
> 
> On Tue, Dec 06, 2016 at 04:34:07PM +0100, Morten Brørup wrote:
>> Hi all,
>> 
>> Being a big fan of strong typing, I really like the concept of
>> explicit endian types. Especially if type mismatches can be caught at
>> compile time.
> 
> +1,
> 
>> However, I think it is too late! That train left the station when the
>> rest of the world - including libraries and headers that might be
>> linked with a DPDK application - decided to use implicit big endian
>> types for network protocols, and has been doing so for decades. And,
>> with all respect, I don't think the DPDK community has the momentum
>> required to change this tradition outside the community.
> 
> I don't think, those types can be use from now on to help new API to
> expose explicitly the type they are handling.  For older ones, it can
> come in a second step, even if there are not so numerous.  Only few of
> them touches the network types.
> 
>> Furthermore: If not enforced throughout DPDK (and beyond), it might
>> confuse more than it helps.
> 
> The current situation is more confusing,  nobody at any layer can rely
> on a precise information, at each function entry we need to verify if
> the callee has already handled the job.  The only solution is to browse
> the code to have this information.
> 
> Think about any function manipulating network headers (like flow director
> or rte_flow) from the API down to the PMD, it may take a lot of time to
> know at the end if the data is CPU or network ordered, with those types
> it takes less than a second.

Still Documentation should handle this problem without code and ABI changes.

> 
> Regards,
> 
> -- 
> Nélio Laranjeiro
> 6WIND

Regards,
Keith


  reply	other threads:[~2016-12-06 16:31 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-09 15:04 Nelio Laranjeiro
2016-12-05 10:09 ` Ananyev, Konstantin
2016-12-05 12:06   ` Nélio Laranjeiro
2016-12-06 11:23     ` Ananyev, Konstantin
2016-12-06 11:55       ` Bruce Richardson
2016-12-06 12:41         ` Ananyev, Konstantin
2016-12-06 13:34           ` Bruce Richardson
2016-12-06 14:45             ` Ananyev, Konstantin
2016-12-06 14:56               ` Wiles, Keith
2016-12-06 15:34                 ` Morten Brørup
2016-12-06 16:28                   ` Nélio Laranjeiro
2016-12-06 16:31                     ` Wiles, Keith [this message]
2016-12-06 16:36                       ` Richardson, Bruce
2016-12-06 17:00                     ` Ananyev, Konstantin
2016-12-06 17:29                       ` Neil Horman
2016-12-06 13:14         ` Nélio Laranjeiro
2016-12-06 13:30           ` Bruce Richardson
2016-12-06 14:06     ` Wiles, Keith
2016-12-08  9:30 ` Nélio Laranjeiro
2016-12-08 13:59   ` Wiles, Keith
2016-12-08 16:06     ` Thomas Monjalon
2016-12-08 15:07   ` Neil Horman
2016-12-08 15:10     ` Ananyev, Konstantin

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=D1B9E864-EE9F-424D-8EE4-D62AC3B4FE90@intel.com \
    --to=keith.wiles@intel.com \
    --cc=adrien.mazarguil@6wind.com \
    --cc=bruce.richardson@intel.com \
    --cc=dev@dpdk.org \
    --cc=konstantin.ananyev@intel.com \
    --cc=mb@smartsharesystems.com \
    --cc=nelio.laranjeiro@6wind.com \
    --cc=olivier.matz@6wind.com \
    --cc=wenzhuo.lu@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).