From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexander Duyck Subject: Re: [driver-core PATCH v8 0/9] Add NUMA aware async_schedule calls Date: Mon, 10 Dec 2018 15:25:04 -0800 Message-ID: References: <154403054034.11544.3978949383914046587.stgit@ahduyck-desk1.jf.intel.com> <20181210192216.GJ28501@garbanzo.do-not-panic.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181210192216.GJ28501@garbanzo.do-not-panic.com> Sender: linux-kernel-owner@vger.kernel.org To: Luis Chamberlain Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, linux-nvdimm@lists.01.org, tj@kernel.org, akpm@linux-foundation.org, linux-pm@vger.kernel.org, jiangshanlai@gmail.com, rafael@kernel.org, len.brown@intel.com, pavel@ucw.cz, zwisler@kernel.org, dan.j.williams@intel.com, dave.jiang@intel.com, bvanassche@acm.org List-Id: linux-pm@vger.kernel.org On Mon, 2018-12-10 at 11:22 -0800, Luis Chamberlain wrote: > On Wed, Dec 05, 2018 at 09:25:13AM -0800, Alexander Duyck wrote: > > This patch set provides functionality that will help to improve the > > locality of the async_schedule calls used to provide deferred > > initialization. > > > > This patch set originally started out focused on just the one call to > > async_schedule_domain in the nvdimm tree that was being used to defer the > > device_add call however after doing some digging I realized the scope of > > this was much broader than I had originally planned. As such I went > > through and reworked the underlying infrastructure down to replacing the > > queue_work call itself with a function of my own and opted to try and > > provide a NUMA aware solution that would work for a broader audience. > > > > In addition I have added several tweaks and/or clean-ups to the front of the > > patch set. Patches 1 through 4 address a number of issues that actually were > > causing the existing async_schedule calls to not show the performance that > > they could due to either not scaling on a per device basis, or due to issues > > that could result in a potential deadlock. For example, patch 4 addresses the > > fact that we were calling async_schedule once per driver instead of once > > per device, and as a result we would have still ended up with devices > > being probed on a non-local node without addressing this first. > > No tests were added. Again, I think it would be good to add test > cases to showcase the old mechanisms, illustrate the new, and ensure > we don't regress both now and also help us ensure we don't regress > moving forward. > > This is all too critical of a path for the kernel, and these changes > are rather instrusive. I'd readlly like to see test code for it now > rather than later. > > Luis Sorry about that. I was more focused on the rewrite of patch 2 and overlooked the comment about lib/test_kmod.c. I'll look into it and see if I can squeeze it in for v9. Thanks. - Alex