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 15:16:51 -0700 Message-ID: <20170119221651.GA1656@obsidianresearch.com> References: <20170118173327.GF32481@mtr-leonro.local> <20170118183127.GC14198@obsidianresearch.com> <5f90fd26-e7bf-bb2a-01f2-6b166f2265e9@sandisk.com> <20170119063326.GJ32481@mtr-leonro.local> <20170119180308.GD8109@obsidianresearch.com> <1484863558.2634.7.camel@sandisk.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1484863558.2634.7.camel@sandisk.com> Sender: netdev-owner@vger.kernel.org To: Bart Van Assche Cc: "leon@kernel.org" , "netdev@vger.kernel.org" , "arielalmogworkemails@gmail.com" , "linux-rdma@vger.kernel.org" , "gerlitz.or@gmail.com" List-Id: linux-rdma@vger.kernel.org On Thu, Jan 19, 2017 at 10:06:12PM +0000, Bart Van Assche wrote: > On Thu, 2017-01-19 at 11:03 -0700, Jason Gunthorpe wrote: > > 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 > > Since the RDMA sysfs ABI defines a user space ABI and since user space > ABIs must be backwards compatible removing the existing sysfs ABI is > not an option. We will need to evaluate on a case-by-case basis whether > new functionality should use sysfs or whether another mechanism should > be used. Not talking about getting rid of it. But if it makes sense to use netlink for the new stuff we should make netlink self-consistent so a netlink user does not have to fall back to sysfs for certain things. Jason