From: Ferruh Yigit <ferruh.yigit@intel.com>
To: Thomas Monjalon <thomas@monjalon.net>, dev@dpdk.org
Cc: bernard.iremonger@intel.com
Subject: Re: [dpdk-dev] [PATCH] ethdev: remove useless parameter in callback process
Date: Thu, 21 Dec 2017 19:08:12 -0800 [thread overview]
Message-ID: <53c8669c-79b9-2f6d-4008-7679aa2cf377@intel.com> (raw)
In-Reply-To: <20171128220951.15317-1-thomas@monjalon.net>
On 11/28/2017 2:09 PM, Thomas Monjalon wrote:
> The pointer to the user parameter of the callback registration is
> automatically pass to the callback function.
> There is no point to allow changing this user parameter by a caller.
> That's why this parameter is always set to NULL by PMDs and set only
> in ethdev layer before calling the callback function.
It can be helpful to mention a little from history:
user cb_arg overwrite introduced by [1], to enable driver pass a pointer to user
callback function and carry some information back from app to driver.
Later to prevent usage of cb_arg as both input and output, an explicit output
(ret_param) added [2] to _rte_eth_dev_callback_process() but previous cb_arg
overwriting kept without any user.
[1]: c1ceaf3ad056 ("ethdev: add an argument to internal callback function")
[2]: d6af1a13d7a1 ("ethdev: add return values to callback process API")
>
> The NULL parameter in the internal callback processing function
> is now removed. It makes clear that the callback parameter is user
> managed and opaque from a DPDK point of view.
>
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
next prev parent reply other threads:[~2017-12-22 3:08 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-28 22:09 Thomas Monjalon
2017-12-22 3:08 ` Ferruh Yigit [this message]
2017-12-28 21:54 ` Thomas Monjalon
2017-12-28 21:56 ` Thomas Monjalon
2017-12-28 22:10 ` [dpdk-dev] [PATCH v2] " Thomas Monjalon
2017-12-29 13:29 ` Thomas Monjalon
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=53c8669c-79b9-2f6d-4008-7679aa2cf377@intel.com \
--to=ferruh.yigit@intel.com \
--cc=bernard.iremonger@intel.com \
--cc=dev@dpdk.org \
--cc=thomas@monjalon.net \
/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).