On 04-Jul-19 10:18 AM, David Marchand wrote:
On Wed, Jul 3, 2019 at 12:45 PM Burakov, Anatoly
<anatoly.bura...@intel.com <mailto:anatoly.bura...@intel.com>> wrote:
On 14-Jun-19 10:39 AM, David Marchand wrote:
> From: Ben Walker <benjamin.wal...@intel.com
<mailto:benjamin.wal...@intel.com>>
>
> When selecting the preferred IOVA mode of the pci bus, the current
> heuristic ("are devices bound?", "are devices bound to UIO?",
"are pmd
> drivers supporting IOVA as VA?" etc..) should honor the device
> white/blacklist so that an unwanted device does not impact the
decision.
>
> There is no reason to consider a device which has no driver
available.
>
> This applies to all OS, so implements this in common code then call a
> OS specific callback.
>
> On Linux side:
> - the VFIO special considerations should be evaluated only if VFIO
> support is built,
> - there is no strong requirement on using VA rather than PA if a
driver
> supports VA, so defaulting to DC in such a case.
>
> Signed-off-by: Ben Walker <benjamin.wal...@intel.com
<mailto:benjamin.wal...@intel.com>>
> Signed-off-by: David Marchand <david.march...@redhat.com
<mailto:david.march...@redhat.com>>
> ---
<snip>
> + const struct rte_pci_device *pdev)
> {
> - struct rte_pci_device *dev = NULL;
> - struct rte_pci_driver *drv = NULL;
> + enum rte_iova_mode iova_mode = RTE_IOVA_DC;
> + static int iommu_no_va = -1;
>
> - FOREACH_DRIVER_ON_PCIBUS(drv) {
> - FOREACH_DEVICE_ON_PCIBUS(dev) {
> - if (!rte_pci_match(drv, dev))
> - continue;
> - /*
> - * just one PCI device needs to be checked
out because
> - * the IOMMU hardware is the same for all
of them.
> - */
> - return pci_one_device_iommu_support_va(dev);
> + switch (pdev->kdrv) {
> + case RTE_KDRV_VFIO: {
> +#ifdef VFIO_PRESENT
> + static int is_vfio_noiommu_enabled = -1;
> +
> + if (is_vfio_noiommu_enabled == -1) {
> + if (rte_vfio_noiommu_is_enabled() == 1)
> + is_vfio_noiommu_enabled = 1;
> + else
> + is_vfio_noiommu_enabled = 0;
> + }
> + if ((pdrv->drv_flags & RTE_PCI_DRV_IOVA_AS_VA) == 0) {
> + iova_mode = RTE_IOVA_PA;
> + } else if (is_vfio_noiommu_enabled != 0) {
> + RTE_LOG(DEBUG, EAL, "Forcing to 'PA',
vfio-noiommu mode configured\n");
> + iova_mode = RTE_IOVA_PA;
> }
> +#endif
> + break;
I'm not too well-versed in bus code, so please excuse my ignorance of
this codebase.
It seems that we would be ignoring drv_flags in case VFIO wasn't
compiled - if the driver has no RTE_PCI_DRV_IOVA_AS_VA flag, i'm pretty
sure we can set IOVA mode to PA without caring about VFIO at all. I
think it would be better to have something like this:
if ((pdrv->drv_flags & RTE_PCI_DRV_IOVA_AS_VA) == 0) {
iova_mode = RTE_IOVA_PA;
break; // early exit
}
If the device is bound to VFIO, but the dpdk binary has no vfio support,
we don't need to consider this device in the decision.
Did I miss something in what you suggest?
Yep, you're correct :)
Reviewed-by: Anatoly Burakov <anatoly.bura...@intel.com>
--
David Marchand
--
Thanks,
Anatoly
