Re: [dpdk-dev] [PATCH 05/10] linuxapp/eal: detect iova mode

[Hemant Agrawal]

On 6/8/2017 4:35 PM, Santosh Shukla wrote:
- Moving late bus scanning to up..just after eal_parsing.
- Detect iova mapping mode based on user provided eal option
  (rte_eal_iova_mode) and result of rte_bus_scan_iommu_class.
Signed-off-by: Santosh Shukla <santosh.shu...@caviumnetworks.com>
Signed-off-by: Jerin Jacob <jerin.ja...@caviumnetworks.com>
---
 lib/librte_eal/linuxapp/eal/eal.c               | 24 ++++++++++++++++++------
 lib/librte_eal/linuxapp/eal/rte_eal_version.map |  1 +
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal.c 
b/lib/librte_eal/linuxapp/eal/eal.c
index 7c78f2dc2..54f42d752 100644
--- a/lib/librte_eal/linuxapp/eal/eal.c
+++ b/lib/librte_eal/linuxapp/eal/eal.c
@@ -122,6 +122,13 @@ struct internal_config internal_config;
 /* used by rte_rdtsc() */
 int rte_cycles_vmware_tsc_map;

+/* Get the iova mode */
+enum rte_iova_mode
+rte_eal_iova_mode(void)
+{
+       return internal_config.iova_mode;
+}
+
 /* Return a pointer to the configuration structure */
 struct rte_config *
 rte_eal_get_configuration(void)
@@ -793,6 +800,17 @@ rte_eal_init(int argc, char **argv)
                return -1;
        }

+       if (rte_bus_scan()) {
+               rte_eal_init_alert("Cannot scan the buses for devices\n");
+               rte_errno = ENODEV;
+               return -1;
+       }
+

The bus scanning includes allocating memory for the devices. It can not 
be moved so early.

I am still testing it out.

+       if (rte_eal_iova_mode() == RTE_IOVA_VA &&
+           rte_bus_get_iommu_class() == RTE_IOVA_VA) {
+               internal_config.iova_mode = RTE_IOVA_VA;
+       }
+
        if (internal_config.no_hugetlbfs == 0 &&
                        internal_config.process_type != RTE_PROC_SECONDARY &&
                        internal_config.xen_dom0_support == 0 &&
@@ -890,12 +908,6 @@ rte_eal_init(int argc, char **argv)
                return -1;
        }

-       if (rte_bus_scan()) {
-               rte_eal_init_alert("Cannot scan the buses for devices\n");
-               rte_errno = ENODEV;
-               return -1;
-       }
-
        RTE_LCORE_FOREACH_SLAVE(i) {

                /*
diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map 
b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
index 6c016c82e..79b005036 100644
--- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
+++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
@@ -204,5 +204,6 @@ DPDK_17.08 {

        rte_pci_get_iommu_class;
        rte_bus_get_iommu_class;
+       rte_eal_iova_mode;

 } DPDK_17.05;