DPDK patches and discussions
 help / color / mirror / Atom feed
From: Remy Horton <remy.horton@intel.com>
To: Yuanhan Liu <yuanhan.liu@linux.intel.com>,
	Thomas Monjalon <thomas.monjalon@6wind.com>
Cc: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
	"Yigit, Ferruh" <ferruh.yigit@intel.com>,
	dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] ethdev: fix wrong memset
Date: Mon, 30 Jan 2017 11:07:56 +0000	[thread overview]
Message-ID: <9681ca16-daf7-6f3f-b6e5-868fd745ab26@intel.com> (raw)
In-Reply-To: <20170128131403.GA20916@yliu-dev.sh.intel.com>


On 28/01/2017 13:14, Yuanhan Liu wrote:
[..]
>> I'll apply the patch from Remy which fixes a case where process creates
>
> I would ask you not to apply that. IMO, his patch may have "fixed" a crash
> he saw, but it doesn't looks like to me it really fixes anything: the driver
> may reference rte_eth_data belongs to another driver -- things can't be
> right afterwards.

I've self-NAK'd it as the code path it was aimed at no longer occurrs.


>> I'll restart this discussion with a bigger picture of what multiproc is,
>> and what are the issues.
>
> Great! And I'm keen to know how the multiproc is actually used in real
> life (and why they don't use multiple thread). Most importantly, does
> people really care about it? (I fixed few virtio multiproc issues that
> I know there are some people/companies using it, and I want to know if
> there are more).

The use-cases I'm coming across are to allow the attaching/detaching of 
external agents mainly for information-reporting purposes, without 
having to leave hooks everywhere. In this case main advantage is the 
relative ease that processes can be hot-plugged in a way threads cannot. 
I suppose something more heavyweight might be a primary process as a 
host physical interconnect, with secondary processes being virtual 
machines - in this case these might be large semi-independent code-bases 
one does not want in the same process image.

To me the major down-side with DPDK's multiprocess model is how 
address-space layout randomisation can trip things up. I know parts of 
the code seems ASLR-safe, but I very much doubt all of it is.

..Remy

  reply	other threads:[~2017-01-30 11:07 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-01-20  8:04 Yuanhan Liu
2017-01-20 10:20 ` Thomas Monjalon
2017-01-20 10:34   ` Yuanhan Liu
2017-01-20 11:09     ` Ferruh Yigit
2017-01-20 18:05     ` Thomas Monjalon
2017-01-20 11:21 ` Ferruh Yigit
2017-01-20 15:27   ` Ferruh Yigit
2017-01-22  2:45     ` Yuanhan Liu
2017-01-23  9:41       ` Ferruh Yigit
2017-01-23 10:34         ` Yuanhan Liu
2017-01-23 11:05           ` Ferruh Yigit
2017-01-23 11:24             ` Yuanhan Liu
2017-01-23 11:32               ` Ferruh Yigit
2017-01-23 11:40                 ` Yuanhan Liu
2017-01-23 11:56                   ` Yuanhan Liu
2017-01-23 12:44                     ` Ananyev, Konstantin
2017-01-23 12:52                       ` Yuanhan Liu
2017-01-23 13:06                         ` Ananyev, Konstantin
2017-01-23 13:09                           ` Ferruh Yigit
2017-01-25 11:16                           ` Thomas Monjalon
2017-01-28 13:14                             ` Yuanhan Liu
2017-01-30 11:07                               ` Remy Horton [this message]
2017-01-24  8:29                     ` Remy Horton

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=9681ca16-daf7-6f3f-b6e5-868fd745ab26@intel.com \
    --to=remy.horton@intel.com \
    --cc=dev@dpdk.org \
    --cc=ferruh.yigit@intel.com \
    --cc=konstantin.ananyev@intel.com \
    --cc=thomas.monjalon@6wind.com \
    --cc=yuanhan.liu@linux.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).