From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Gleixner Subject: Re: [PATCH v1 0/2] genirq: support multiple IRQ notifier. Date: Fri, 25 Mar 2016 21:49:51 +0100 (CET) Message-ID: References: <20160325193243.GA30485@infradead.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <20160325193243.GA30485@infradead.org> Sender: linux-kernel-owner@vger.kernel.org To: Christoph Hellwig Cc: Weongyo Jeong , linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-scsi@vger.kernel.org, Mike Marciniszyn , "James E.J. Bottomley" , "Martin K. Petersen" List-Id: linux-scsi@vger.kernel.org On Fri, 25 Mar 2016, Christoph Hellwig wrote: > On Fri, Mar 25, 2016 at 08:51:51AM -0700, Weongyo Jeong wrote: > > Each irq_desc only supports one IRQ affinity notifier at current > > implementation so when we try to register another notifier, it silently > > unregister previous entry and register new one. > > > > However the problem is that if CONFIG_RFS_ACCEL is set, at current > > implementation no way to set additional IRQ affinity notifier for > > some NIC cards RFS enabled because it already used for RFS. > > With this patch we can register multiple IRQ affinity notifiers. > > The whole concept of these irq affinity notifiers seems wrong to me. > > If a device supports MSI-X it should simply request per-cpu or per-node > vectors and we should prevent affinity changes for them. You beat me to it. I'm having a half baken prototype to implement this at the core level. Will post next week. Thanks, tglx