On Wed, Feb 26, 2020 at 8:50 PM David Christensen
<d...@linux.vnet.ibm.com> wrote:
>
> Bare metal PowerNV systems include a DPDK supported IOMMU that allows
> IOVA=VA support. Test for the platform type and report virtual address
> support if running on a PowerNV system.
I can't test it, so I'll trust you on this :-).
Comments below.
>
> Signed-off-by: David Christensen <d...@linux.vnet.ibm.com>
> ---
> drivers/bus/pci/linux/pci.c | 29 +++++++++++++++++++++++++++++
> 1 file changed, 29 insertions(+)
>
> diff --git a/drivers/bus/pci/linux/pci.c b/drivers/bus/pci/linux/pci.c
> index 740a2cdad..696dc177e 100644
> --- a/drivers/bus/pci/linux/pci.c
> +++ b/drivers/bus/pci/linux/pci.c
> @@ -549,6 +549,35 @@ pci_device_iommu_support_va(const struct rte_pci_device
> *dev)
> bool
> pci_device_iommu_support_va(__rte_unused const struct rte_pci_device *dev)
> {
> + /*
> + * IOMMU is always present on a PowerNV host (IOMMUv2).
> + * IOMMU is also present in a KVM/QEMU VM (IOMMUv1) but is not
> + * currently supported by DPDK. Test for our current environment
> + * and report VA support as appropriate.
> + */
> +
> + char *line = 0;
Nit: NULL
> + size_t len = 0;
> + char filename[PATH_MAX] = "/proc/cpuinfo";
> + FILE *fp = fopen(filename, "r");
> +
> + if (fp == NULL) {
> + RTE_LOG(ERR, EAL, "%s(): can't open %s: %s\n",
> + __func__, filename, strerror(errno));
> + return false;
> + }
> +
> + /* Check for a PowerNV platform */
> + while (getline(&line, &len, fp) != -1) {
>From here, you leak line.
man getline
ssize_t getline(char **lineptr, size_t *n, FILE *stream);
If *lineptr is NULL, then getline() will allocate a buffer for storing
the line, which should be freed by the user program. (In this case,
the value in *n is ignored.)
> + if (strstr(line, "platform") != NULL)
Nit, to avoid multiple level of indent, how about invert the check:
if (strstr(line, "platform") == NULL)
continue;
> + if (strstr(line, "PowerNV") != NULL) {
> + RTE_LOG(DEBUG, EAL, "Running on a PowerNV
> system\n");
Not really helpful, it does not indicate that this system iommu supports VA.
> + fclose(fp);
> + return true;
> + }
> + }
> + fclose(fp);
> +
> return false;
> }
> #else
> --
> 2.18.1
>
--
David Marchand
