From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [RFC] RESEND - rdmatool - tool for RDMA users Date: Thu, 19 Jan 2017 11:03:08 -0700 Message-ID: <20170119180308.GD8109@obsidianresearch.com> References: <20170118173327.GF32481@mtr-leonro.local> <20170118183127.GC14198@obsidianresearch.com> <5f90fd26-e7bf-bb2a-01f2-6b166f2265e9@sandisk.com> <20170119063326.GJ32481@mtr-leonro.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20170119063326.GJ32481-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Leon Romanovsky Cc: Bart Van Assche , Or Gerlitz , Ariel Almog , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Linux Netdev List List-Id: linux-rdma@vger.kernel.org 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 .. Jason -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html