From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shijith Thotton Subject: Re: [PATCH v2] igb_uio: issue FLR during open and release of device file Date: Mon, 10 Jul 2017 12:40:49 +0530 Message-ID: <20170710071048.GA5231@localhost.localdomain> References: <1497260285-27536-1-git-send-email-shijith.thotton@caviumnetworks.com> <1499426031-2664-1-git-send-email-shijith.thotton@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "dev@dpdk.org" , "Yigit, Ferruh" , Gregory Etelson , Thomas Monjalon , Stephen Hemminger , "Lu, Wenzhuo" To: "Tan, Jianfeng" Return-path: Received: from NAM03-CO1-obe.outbound.protection.outlook.com (mail-co1nam03on0045.outbound.protection.outlook.com [104.47.40.45]) by dpdk.org (Postfix) with ESMTP id 0A7A27CBB for ; Mon, 10 Jul 2017 09:11:07 +0200 (CEST) Content-Disposition: inline In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Mon, Jul 10, 2017 at 03:38:34AM +0000, Tan, Jianfeng wrote: > Hi Thotton, > > > -----Original Message----- > > From: Shijith Thotton [mailto:shijith.thotton@caviumnetworks.com] > > Sent: Friday, July 7, 2017 7:14 PM > > To: dev@dpdk.org > > Cc: Yigit, Ferruh; Gregory Etelson; Thomas Monjalon; Stephen Hemminger; > > Tan, Jianfeng; Lu, Wenzhuo > > Subject: [PATCH v2] igb_uio: issue FLR during open and release of device file > > > > Set UIO info device file operations open and release. Call pci reset > > function inside open and release to clear device state at start and end. > > Copied this behaviour from vfio_pci kernel module code. With this patch, > > it is not mandatory to issue FLR by PMD's during init and close. > > I'm afraid this will not work for restarted DPDK process. In current probe(), we set up the I/O mem and I/O port; and those sys files are used by EAL IGB_UIO initialization code to map I/O mem and port. After reset in release(), we will lose those sys files in next open(). > > Thanks, > Jianfeng > > > > > Bus master enable and disable are added in open and release respectively > > to take care of device DMA. > > > > Signed-off-by: Shijith Thotton > > --- > > v2 changes: > > - Replaced pci_try_reset_function with pci_reset_function as it is not > > available in older kernel versions. > > > > v1 changes: > > - Added pci set master inside open and clear master inside release. > > - Remove obvious comments. > > > > RFC: http://dpdk.org/ml/archives/dev/2017-May/066917.html > > > > lib/librte_eal/linuxapp/igb_uio/igb_uio.c | 33 > > +++++++++++++++++++++++++++++++ > > 1 file changed, 33 insertions(+) > > > > diff --git a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > index b9d427c..07a19a3 100644 > > --- a/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > +++ b/lib/librte_eal/linuxapp/igb_uio/igb_uio.c > > @@ -170,6 +170,37 @@ struct rte_uio_pci_dev { > > return IRQ_HANDLED; > > } > > > > +/** > > + * This gets called while opening uio device file. > > + */ > > +static int > > +igbuio_pci_open(struct uio_info *info, struct inode *inode) > > +{ > > + struct rte_uio_pci_dev *udev = info->priv; > > + struct pci_dev *dev = udev->pdev; > > + > > + pci_reset_function(dev); > > + > > + /* set bus master, which was cleared by the reset function */ > > + pci_set_master(dev); > > + > > + return 0; > > +} > > + > > +static int > > +igbuio_pci_release(struct uio_info *info, struct inode *inode) > > +{ > > + struct rte_uio_pci_dev *udev = info->priv; > > + struct pci_dev *dev = udev->pdev; > > + > > + /* stop the device from further DMA */ > > + pci_clear_master(dev); > > + > > + pci_reset_function(dev); > > + > > + return 0; > > +} > > + > > #ifdef CONFIG_XEN_DOM0 > > static int > > igbuio_dom0_mmap_phys(struct uio_info *info, struct vm_area_struct > > *vma) > > @@ -372,6 +403,8 @@ struct rte_uio_pci_dev { > > udev->info.version = "0.1"; > > udev->info.handler = igbuio_pci_irqhandler; > > udev->info.irqcontrol = igbuio_pci_irqcontrol; > > + udev->info.open = igbuio_pci_open; > > + udev->info.release = igbuio_pci_release; > > #ifdef CONFIG_XEN_DOM0 > > /* check if the driver run on Xen Dom0 */ > > if (xen_initial_domain()) > > -- > > 1.8.3.1 > Hi Jianfeng, I have tested the patch with LiquidIO VFs in VM using testpmd and could not see any issue over multiple runs. Thanks, Shijith