From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754254AbcCYTcr (ORCPT ); Fri, 25 Mar 2016 15:32:47 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:34816 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752859AbcCYTcp (ORCPT ); Fri, 25 Mar 2016 15:32:45 -0400 Date: Fri, 25 Mar 2016 12:32:43 -0700 From: Christoph Hellwig To: Weongyo Jeong Cc: linux-kernel@vger.kernel.org, linux-rdma@vger.kernel.org, linux-scsi@vger.kernel.org, Thomas Gleixner , Mike Marciniszyn , "James E.J. Bottomley" , "Martin K. Petersen" Subject: Re: [PATCH v1 0/2] genirq: support multiple IRQ notifier. Message-ID: <20160325193243.GA30485@infradead.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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.