From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] pci/linux: use RTE_IOVA_VA whenever possible Date: Sun, 28 Oct 2018 19:56:07 +0100 Message-ID: <2254496.FTyVADVnFM@xps> References: <20180907145340.79670-1-dariusz.stojaczyk@intel.com> <93d12b45-d0a9-ab28-5ead-c3424067a062@intel.com> <20181011104702.GA18152@jerin> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, Jerin Jacob , "Burakov, Anatoly" , Alejandro Lucero , "Shukla, Santosh" , Hemant Agrawal , Maxime Coquelin , "chas3@att.com" To: "dariusz.stojaczyk@intel.com" Return-path: Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) by dpdk.org (Postfix) with ESMTP id 5FFC22965 for ; Sun, 28 Oct 2018 19:56:05 +0100 (CET) In-Reply-To: <20181011104702.GA18152@jerin> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 11/10/2018 12:47, Jerin Jacob: > -----Original Message----- > > Date: Thu, 11 Oct 2018 11:26:05 +0100 > > From: "Burakov, Anatoly" > > To: Alejandro Lucero , > > dariusz.stojaczyk@intel.com > > CC: dev , Santosh Shukla , > > Hemant Agrawal , Jerin Jacob > > , Maxime Coquelin > > , chas3@att.com > > Subject: Re: [dpdk-dev] [PATCH] pci/linux: use RTE_IOVA_VA whenever possible > > User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 > > Thunderbird/52.9.1 > > > > > > On 11-Oct-18 11:00 AM, Alejandro Lucero wrote: > > > On Fri, Sep 7, 2018 at 3:55 PM Darek Stojaczyk > > > wrote: > > > > > > > This allows DPDK to use RTE_IOVA_VA with VFIO/UIO-bound PCI > > > > devices present on the system, but not attached to any > > > > rte_pci_driver at the time of init. > > > > > > > > So far we used RTE_IOVA_VA whenever there was at least one > > > > device attached to a driver with an RTE_PCI_DRV_IOVA_AS_VA flag, > > > > meaning that other drivers which didn't explicitly report such > > > > flag could have been forced to work in RTE_IOVA_VA as well. > > > > > > > > > > This is the opposite. Just one device not being able to use IOVA VA makes > > > all to use IOVA PA. > > > > > > > > > > > > > > This patch makes the RTE_PCI_DRV_IOVA_AS_VA explicitly a hint. > > > > If it's set, but RTE_IOVA_VA cannot be used, then EAL will print > > > > a proper warning. > > > > > > > > Signed-off-by: Darek Stojaczyk > > > > --- > > > > drivers/bus/pci/linux/pci.c | 11 +++++------ > > > > 1 file changed, 5 insertions(+), 6 deletions(-) > > > > > > > > diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c > > > > index 04648ac93..961e24024 100644 > > > > --- a/drivers/bus/pci/linux/pci.c > > > > +++ b/drivers/bus/pci/linux/pci.c > > > > @@ -534,7 +534,7 @@ pci_one_device_bound_uio(void) > > > > * Any one of the device has iova as va > > > > */ > > > > static inline int > > > > -pci_one_device_has_iova_va(void) > > > > +pci_one_device_want_iova_va(void) > > > > { > > > > struct rte_pci_device *dev = NULL; > > > > struct rte_pci_driver *drv = NULL; > > > > @@ -635,7 +635,7 @@ rte_pci_get_iommu_class(void) > > > > { > > > > bool is_bound; > > > > bool is_vfio_noiommu_enabled = true; > > > > - bool has_iova_va; > > > > + bool want_iova_va; > > > > bool is_bound_uio; > > > > bool iommu_no_va; > > > > > > > > @@ -643,7 +643,7 @@ rte_pci_get_iommu_class(void) > > > > if (!is_bound) > > > > return RTE_IOVA_DC; > > > > > > > > - has_iova_va = pci_one_device_has_iova_va(); > > > > + want_iova_va = pci_one_device_want_iova_va(); > > > > is_bound_uio = pci_one_device_bound_uio(); > > > > iommu_no_va = !pci_devices_iommu_support_va(); > > > > #ifdef VFIO_PRESENT > > > > @@ -651,11 +651,10 @@ rte_pci_get_iommu_class(void) > > > > true : false; > > > > #endif > > > > > > > > - if (has_iova_va && !is_bound_uio && !is_vfio_noiommu_enabled && > > > > - !iommu_no_va) > > > > + if (!is_bound_uio && !is_vfio_noiommu_enabled && !iommu_no_va) > > > > return RTE_IOVA_VA; > > > > > > > > > > This is wrong. A device not able to work with IOVA VA will fail. > > > > > > > > > > > > > > - if (has_iova_va) { > > > > + if (want_iova_va) { > > > > RTE_LOG(WARNING, EAL, "Some devices want iova as va but pa > > > > will be used because.. "); > > > > if (is_vfio_noiommu_enabled) > > > > RTE_LOG(WARNING, EAL, "vfio-noiommu mode > > > > configured\n"); > > > > -- > > > > 2.17.1 > > > > > > > > > > > > > > > For these cases, i think the explicit IOVA mode on command line should > > work better. If the device has not reported IOVA as VA capability, it is > > to be assumed unsupported. > > Yes. Patch marked as rejected