From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 44E58C5519F for ; Wed, 25 Nov 2020 14:54:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA6CC20857 for ; Wed, 25 Nov 2020 14:54:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="hwGOzEWe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726908AbgKYOyY (ORCPT ); Wed, 25 Nov 2020 09:54:24 -0500 Received: from mail.kernel.org ([198.145.29.99]:44382 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726060AbgKYOyY (ORCPT ); Wed, 25 Nov 2020 09:54:24 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8B2F6206B5; Wed, 25 Nov 2020 14:54:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1606316063; bh=tHkXsp0lYry+LrxVumeVX78AT7FJzfcqs1X3jktXgN0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=hwGOzEWeVZia6AU1cymJ7WZ6js+joX28GR1U4JTqy6BD2mMckiMcBOF+CYurZK7L6 bDuWwL4nLFxty8Yusdfg28cQQnzAO94P28hR0leptdyJinLMFTS5DOpfa4YEdDhCmn wR5nipU8wsdwL033EwxZO7YN0B+/2gJtXHeI6BHQ= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1khwBZ-00DY7S-Fm; Wed, 25 Nov 2020 14:54:21 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 25 Nov 2020 14:54:21 +0000 From: Marc Zyngier To: Laurent Vivier Cc: Thomas Gleixner , linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Paul Mackerras , linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Benjamin Herrenschmidt , "Michael S . Tsirkin" , Greg Kurz , Christoph Hellwig , Michael Ellerman Subject: Re: [PATCH v2 1/2] genirq: add an irq_create_mapping_affinity() function In-Reply-To: References: <20201125111657.1141295-1-lvivier@redhat.com> <20201125111657.1141295-2-lvivier@redhat.com> <87sg8xk1yi.fsf@nanos.tec.linutronix.de> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <5100171ff6d4c3efffe008e1e0bf3707@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: lvivier@redhat.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, paulus@samba.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, benh@kernel.crashing.org, mst@redhat.com, groug@kaod.org, hch@lst.de, mpe@ellerman.id.au X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 2020-11-25 14:09, Laurent Vivier wrote: > On 25/11/2020 14:20, Thomas Gleixner wrote: >> Laurent, >> >> On Wed, Nov 25 2020 at 12:16, Laurent Vivier wrote: >> >> The proper subsystem prefix is: 'genirq/irqdomain:' and the first >> letter >> after the colon wants to be uppercase. > > Ok. > >>> This function adds an affinity parameter to irq_create_mapping(). >>> This parameter is needed to pass it to irq_domain_alloc_descs(). >> >> A changelog has to explain the WHY. 'The parameter is needed' is not >> really useful information. >> > > The reason of this change is explained in PATCH 2. > > I have two patches, one to change the interface with no functional > change (PATCH 1) and > one to fix the problem (PATCH 2). Moreover they don't cover the same > subsystems. > > I can either: > - merge the two patches > - or make a reference in the changelog of PATCH 1 to PATCH 2 > (something like "(see folowing patch "powerpc/pseries: pass MSI > affinity to > irq_create_mapping()")") > - or copy some information from PATCH 2 > (something like "this parameter is needed by rtas_setup_msi_irqs() > to pass the affinity > to irq_domain_alloc_descs() to fix multiqueue affinity") > > What do you prefer? How about something like this for the first patch: "There is currently no way to convey the affinity of an interrupt via irq_create_mapping(), which creates issues for devices that expect that affinity to be managed by the kernel. In order to sort this out, rename irq_create_mapping() to irq_create_mapping_affinity() with an additional affinity parameter that can conveniently passed down to irq_domain_alloc_descs(). irq_create_mapping() is then re-implemented as a wrapper around irq_create_mapping_affinity()." Thanks, M. -- Jazz is not dead. It just smells funny...