From: Leon Romanovsky <leon@kernel•org>
To: Jason Gunthorpe <jgunthorpe@obsidianresearch•com>
Cc: Bart Van Assche <bart.vanassche@sandisk•com>,
Or Gerlitz <gerlitz.or@gmail•com>,
Ariel Almog <arielalmogworkemails@gmail•com>,
"linux-rdma@vger•kernel.org" <linux-rdma@vger•kernel.org>,
Linux Netdev List <netdev@vger•kernel.org>
Subject: Re: [RFC] RESEND - rdmatool - tool for RDMA users
Date: Thu, 19 Jan 2017 21:12:57 +0200 [thread overview]
Message-ID: <20170119191257.GA28570@mtr-leonro.local> (raw)
In-Reply-To: <20170119180308.GD8109@obsidianresearch.com>
[-- Attachment #1: Type: text/plain, Size: 2586 bytes --]
On Thu, Jan 19, 2017 at 11:03:08AM -0700, Jason Gunthorpe wrote:
> On Thu, Jan 19, 2017 at 08:33:26AM +0200, Leon Romanovsky wrote:
> > On Wed, Jan 18, 2017 at 01:45:14PM -0800, Bart Van Assche wrote:
> > > On 01/18/2017 10:31 AM, Jason Gunthorpe wrote:
> > > > I think it depends on what this tool is supposed to cover, but based
> > > > on the description, I would start with netlink-only.
> > > >
> > > > The only place verbs covers a similar ground is in 'device
> > > > capabilities' - for some of that you might want to open a new-uAPI
> > > > verbs fd, but even the capability data from that would not be
> > > > totally offensive to be accessed over netlink.
> > > >
> > > > IMHO netlink should cover almost everything found in sysfs today.
> > >
> > > We would need a very strong argument to introduce a netlink API that
> > > duplicates existing sysfs API functionality. Since the sysfs API is
> > > extensible, why not extend that API further? E.g. the SCST sysfs API
> > > shows that more is possible with sysfs than what most kernel drivers
> > > realize.
> >
> > We didn't look deeply on sysfs mainly because it is unpopular
> > in netdev community. Maybe we were misled and it is simply not true.
>
> sysfs is unpopular because the 'one value per file' dogma is laregly
> unsuitable for complex mulit-value atomic changes which are common in
> netdev. You can force it to work, but it is pretty horrible..
>
> It is also very expensive if you want to shuttle a lot of data, eg I
> could not see doing something like 'netstat' for IB through sysfs
>
> Maybe you should start by showing some examples of command out you
> wish to have in a rdmatool ..
Ariel wrote very simplified version in his proposal:
Functionality
*************
The rdmatool will provide a platform which can grow as needed. The
initial functionality might include:
* help – man page
* version – version number
* statistics – RDMA statistics – such as port and QP statistics
To allow easy reading of statistics, we offer to use a filter
functionality, allowing reading of statistics families, such
as link layer, error counters, etc.
* protocol – RoCE/iWARP/InfiniBand related configuration, such as RDMA
congestion configuration and statistics
* query – RDMA objects (qp, cq, srq, ..) information such as owner,
status, type
* debug – an interface to allow read and write from user space
to the provider RDMA driver, exposing debug information.
Commands similar to "ip" program.
>
> Jason
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2017-01-19 19:13 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-18 15:19 [RFC] RESEND - rdmatool - tool for RDMA users Ariel Almog
[not found] ` <CABvr3-GZQs51Sn3XagTsepsy3CHvx6P=GVJzefajbNt9jxz9Kg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2017-01-18 16:48 ` Or Gerlitz
2017-01-18 17:33 ` Leon Romanovsky
2017-01-18 17:50 ` Or Gerlitz
2017-01-18 18:28 ` Leon Romanovsky
2017-01-18 18:31 ` Jason Gunthorpe
2017-01-18 21:45 ` Bart Van Assche
[not found] ` <5f90fd26-e7bf-bb2a-01f2-6b166f2265e9-XdAiOPVOjttBDgjK7y7TUQ@public.gmane.org>
2017-01-19 6:33 ` Leon Romanovsky
[not found] ` <20170119063326.GJ32481-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2017-01-19 18:03 ` Jason Gunthorpe
2017-01-19 19:12 ` Leon Romanovsky [this message]
2017-01-19 22:06 ` Bart Van Assche
2017-01-19 22:16 ` Jason Gunthorpe
[not found] ` <20170119180308.GD8109-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2017-01-31 11:38 ` Ariel Almog
2017-01-19 6:04 ` Leon Romanovsky
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=20170119191257.GA28570@mtr-leonro.local \
--to=leon@kernel$(echo .)org \
--cc=arielalmogworkemails@gmail$(echo .)com \
--cc=bart.vanassche@sandisk$(echo .)com \
--cc=gerlitz.or@gmail$(echo .)com \
--cc=jgunthorpe@obsidianresearch$(echo .)com \
--cc=linux-rdma@vger$(echo .)kernel.org \
--cc=netdev@vger$(echo .)kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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