From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Thu, 03 Oct 2013 10:03:06 +0200 (CEST) Received: from mail-ee0-f47.google.com ([74.125.83.47]:50859 "EHLO mail-ee0-f47.google.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S6819540Ab3JCIDDnXpxB (ORCPT ); Thu, 3 Oct 2013 10:03:03 +0200 Received: by mail-ee0-f47.google.com with SMTP id d49so896054eek.20 for ; Thu, 03 Oct 2013 01:02:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:organization:mime-version:content-type :content-transfer-encoding; bh=K9lP+ptdyKXFDeCSWmRsk/PGpckF0vT1dyAejpdevRs=; b=OZ8BWzZVOXW2jDT514RY3Rt0cdM/DocCIuVD3gCJR5fSsu9a+vNVCa/QKA9IDmRQ/h D9ivhnb33OZgve+w9QSvJI2SgnmahCqKBujW/LvYGj6iZ67njlvWCgoCSAOO8U8vZaEJ aeKc55XQVRXxWcZKtmpNSheseiPyKEAJRgMH6jikDgWq0IFPbJBL5LOGI7zNwXX651YB 17ap3kxz3KDUAWEokIm2yFH+2ehQIgsbuAnxC4Vysf1BSl2I0SsGWZVHNn1ewDdMEyuk hJ0XsHz4ErnzKSbPSnSo/iQRYX9l7/UEnqivzflwQmw00MeAug84anfp8cY/TaWq1MfS WKbg== X-Gm-Message-State: ALoCoQlx6GzSeaVxOcXIIwunmHGCNgk9RQS5Y8A+oWqLtm8eF950VPVb54NQugPfDVy1e85EgqFR X-Received: by 10.14.115.133 with SMTP id e5mr10797848eeh.27.1380787378085; Thu, 03 Oct 2013 01:02:58 -0700 (PDT) Received: from jpm-OptiPlex-GX620 (out.voltaire.com. [193.47.165.251]) by mx.google.com with ESMTPSA id b45sm12713094eef.4.1969.12.31.16.00.00 (version=SSLv3 cipher=RC4-SHA bits=128/128); Thu, 03 Oct 2013 01:02:56 -0700 (PDT) Date: Thu, 3 Oct 2013 11:02:54 +0300 From: Jack Morgenstein To: Alexander Gordeev Cc: linux-kernel@vger.kernel.org, Bjorn Helgaas , Ralf Baechle , Michael Ellerman , Benjamin Herrenschmidt , Martin Schwidefsky , Ingo Molnar , Tejun Heo , Dan Williams , Andy King , Jon Mason , Matt Porter , linux-pci@vger.kernel.org, linux-mips@linux-mips.org, linuxppc-dev@lists.ozlabs.org, linux390@de.ibm.com, linux-s390@vger.kernel.org, x86@kernel.org, linux-ide@vger.kernel.org, iss_storagedev@hp.com, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, netdev@vger.kernel.org, e1000-devel@lists.sourceforge.net, linux-driver@qlogic.com, Solarflare linux maintainers , "VMware, Inc." , linux-scsi@vger.kernel.org, ogerlitz@mellanox.com, eli@mellanox.com Subject: Re: [PATCH RFC 46/77] mlx4: Update MSI/MSI-X interrupts enablement code Message-ID: <20131003110254.5f10fbb8@jpm-OptiPlex-GX620> In-Reply-To: References: Organization: Mellanox X-Mailer: Claws Mail 3.8.1 (GTK+ 2.24.17; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 38180 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: jackm@dev.mellanox.co.il Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On Wed, 2 Oct 2013 12:49:02 +0200 Alexander Gordeev wrote: NACK. This change does not do anything logically as far as I can tell. pci_enable_msix in the current upstream kernel itself calls pci_msix_table_size. The current code yields the same results as the code suggested below. (i.e., the suggested code has no effect on optimality). BTW, pci_msix_table_size never returns a value < 0 (if msix is not enabled, it returns 0 for the table size), so the (err < 0) check here is not correct. (I also do not like using "err" here anyway for the value returned by pci_msix_table_size(). There is no error here, and it is simply confusing. -Jack > As result of recent re-design of the MSI/MSI-X interrupts enabling > pattern this driver has to be updated to use the new technique to > obtain a optimal number of MSI/MSI-X interrupts required. > > Signed-off-by: Alexander Gordeev > --- > drivers/net/ethernet/mellanox/mlx4/main.c | 17 ++++++++--------- > 1 files changed, 8 insertions(+), 9 deletions(-) > > diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c > b/drivers/net/ethernet/mellanox/mlx4/main.c index 60c9f4f..377a5ea > 100644 --- a/drivers/net/ethernet/mellanox/mlx4/main.c > +++ b/drivers/net/ethernet/mellanox/mlx4/main.c > @@ -1852,8 +1852,16 @@ static void mlx4_enable_msi_x(struct mlx4_dev > *dev) int i; > > if (msi_x) { > + err = pci_msix_table_size(dev->pdev); > + if (err < 0) > + goto no_msi; > + > + /* Try if at least 2 vectors are available */ > nreq = min_t(int, dev->caps.num_eqs - > dev->caps.reserved_eqs, nreq); > + nreq = min_t(int, nreq, err); > + if (nreq < 2) > + goto no_msi; > > entries = kcalloc(nreq, sizeof *entries, GFP_KERNEL); > if (!entries) > @@ -1862,17 +1870,8 @@ static void mlx4_enable_msi_x(struct mlx4_dev > *dev) for (i = 0; i < nreq; ++i) > entries[i].entry = i; > > - retry: > err = pci_enable_msix(dev->pdev, entries, nreq); > if (err) { > - /* Try again if at least 2 vectors are > available */ > - if (err > 1) { > - mlx4_info(dev, "Requested %d > vectors, " > - "but only %d MSI-X vectors > available, " > - "trying again\n", nreq, > err); > - nreq = err; > - goto retry; > - } > kfree(entries); > goto no_msi; > }