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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 90350C43381 for ; Thu, 14 Feb 2019 23:56:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 67A7E20656 for ; Thu, 14 Feb 2019 23:56:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729462AbfBNX4E (ORCPT ); Thu, 14 Feb 2019 18:56:04 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:51532 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726178AbfBNX4E (ORCPT ); Thu, 14 Feb 2019 18:56:04 -0500 Received: from p5492e0d8.dip0.t-ipconnect.de ([84.146.224.216] helo=nanos) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1guQrB-0004g2-Ji; Fri, 15 Feb 2019 00:55:53 +0100 Date: Fri, 15 Feb 2019 00:55:53 +0100 (CET) From: Thomas Gleixner To: Ming Lei cc: LKML , Christoph Hellwig , Bjorn Helgaas , Jens Axboe , linux-block@vger.kernel.org, Sagi Grimberg , linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, Keith Busch , Marc Zyngier , Sumit Saxena , Kashyap Desai , Shivasharan Srikanteshwara Subject: Re: [patch V5 4/8] nvme-pci: Simplify interrupt allocation In-Reply-To: <20190214224136.GA18764@ming.t460p> Message-ID: References: <20190214204755.819014197@linutronix.de> <20190214211759.699390983@linutronix.de> <20190214224136.GA18764@ming.t460p> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Fri, 15 Feb 2019, Ming Lei wrote: > > + * If only one interrupt is available, combine write and read > > + * queues. If 'write_queues' is set, ensure it leaves room for at > > + * least one read queue. > > + */ > > + if (nrirqs == 1) > > + nr_read_queues = 0; > > + else if (write_queues >= nrirqs) > > + nr_read_queues = nrirqs - 1; > > + else > > + nr_read_queues = nrirqs - write_queues; > > + > > + dev->io_queues[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues; > > + affd->set_size[HCTX_TYPE_DEFAULT] = nrirqs - nr_read_queues; > > + dev->io_queues[HCTX_TYPE_READ] = nr_read_queues; > > + affd->set_size[HCTX_TYPE_READ] = nr_read_queues; > > + affd->nr_sets = nr_read_queues ? 2 : 1; > > } > > .calc_sets is called only if more than .pre_vectors is available, > then dev->io_queues[HCTX_TYPE_DEFAULT] may not be set in case of > (nvecs == affd->pre_vectors + affd->post_vectors). Hmm, good catch. The delta patch below should fix that, but I have to go through all the possible cases in pci_alloc_irq_vectors_affinity() once more with brain awake. Thanks, tglx 8<--------------------- --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2092,6 +2092,10 @@ static int nvme_setup_irqs(struct nvme_d } dev->io_queues[HCTX_TYPE_POLL] = this_p_queues; + /* Initialize for the single interrupt case */ + dev->io_queues[HCTX_TYPE_DEFAULT] = 1; + dev->io_queues[HCTX_TYPE_READ] = 0; + return pci_alloc_irq_vectors_affinity(pdev, 1, irq_queues, PCI_IRQ_ALL_TYPES | PCI_IRQ_AFFINITY, &affd); }