From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id CD3411518 for ; Fri, 28 Nov 2014 09:15:46 +0100 (CET) Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id sAS8FhI4021019 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 28 Nov 2014 03:15:44 -0500 Received: from dhcp-66-71-51.eng.nay.redhat.com (dhcp-66-71-51.eng.nay.redhat.com [10.66.71.51] (may be forged)) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id sAS8FfmG022226; Fri, 28 Nov 2014 03:15:42 -0500 Message-ID: <54782EB5.7060409@redhat.com> Date: Fri, 28 Nov 2014 16:13:41 +0800 From: Jincheng Miao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Thomas Monjalon References: <1414741039-3531-1-git-send-email-jmiao@redhat.com> <1414741039-3531-2-git-send-email-jmiao@redhat.com> <7579030.6nSHmmQ36o@xps13> In-Reply-To: <7579030.6nSHmmQ36o@xps13> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 Cc: dev@dpdk.org Subject: Re: [dpdk-dev] [PATCH v2 1/2] igb_uio: compatible with upstream longterm kernel and RHEL6 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 28 Nov 2014 08:15:47 -0000 On 11/28/2014 01:01 AM, Thomas Monjalon wrote: > 2014-10-31 15:37, Jincheng Miao: >> Function pci_num_vf() is introduced from upstream linux-2.6.34. So >> this patch make compatible with longterm kernel linux-2.6.32.63. >> >> For RHEL6's kernel, although it is based on linux-2.6.32, it has >> pci_num_vf() implementation. As the same with commit 11ba0426, >> pci_num_vf() is defined from RHEL6. So we should check the macro >> RHEL_RELEASE_CODE to consider this situation. > Please, could you explain in which case CONFIG_PCI_IOV is defined? > The logic is a bit difficult to understand. Yep, there is a little confusion for pci_num_vf(): 1. it is available when CONFIG_PCI_IOV is defined. 2. it is introduced from upstream kernel v2.6.34 (fb8a0d9) 3. it is implemented from RHEL6.0, although the kernel version is 2.6.32. The logic of this patch is: #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \ (!(defined(RHEL_RELEASE_CODE) && RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(6, 0) && defined(CONFIG_PCI_IOV))) Firstly it detects kernel version, if it is less than 2.6.34, and it is not RHEL-specified, then define pci_num_vf(). Secondly, it deals with RHEL-specified. If it is RHEL6.0 or later, and CONFIG_PCI_IOV is defined. we should not define pci_num_vf(). If any of these conditions is not reached, pci_num_vf() should be defined. Some days ago, I setup dpdk for longterm kernel 2.6.32.63, and got error: ``` CC [M] /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.o /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c: In function ‘show_max_vfs’: /root/dpdk-source/build/build/lib/librte_eal/linuxapp/igb_uio/igb_uio.c:75: error: implicit declaration of function ‘pci_num_vf’ ``` This problem is introduced by commit 11ba04265 commit 11ba04265cfd2a53c12c030fcaa5dfe7eed39a42 Author: Guillaume Gaudonville Date: Wed Sep 3 10:18:23 2014 +0200 igb_uio: fix build on RHEL 6.3 - pci_num_vf() is already defined in RHEL 6 - pci_intx_mask_supported is already defined in RHEL 6.3 - pci_check_and_mask_intx is already defined in RHEL 6.3 Signed-off-by: Guillaume Gaudonville Signed-off-by: David Marchand Signed-off-by: Thomas Monjalon +#if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \ + !defined(CONFIG_PCI_IOV) That is because longterm kernel 2.6.32.63 defined CONFIG_PCI_IOV, but it lacks pci_num_vf(), after above processing, pci_num_vf() is still not existed, then build fail. My patch could work around it, and can deal with RHEL-specified kernel. >> #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 34) && \ >> - !defined(CONFIG_PCI_IOV) >> + (!(defined(RHEL_RELEASE_CODE) && \ >> + RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(6, 0) && \ >> + defined(CONFIG_PCI_IOV))) >> >> static int pci_num_vf(struct pci_dev *dev) >> {