Thanks you for your review Jerin. See my responses are inline.
On 2020-03-20 06:24, Jerin Jacob wrote:
On Fri, Feb 21, 2020 at 4:22 AM David Wilder <dwil...@us.ibm.com>
wrote:
If --no-huge is set and iova-mode has not been specified force VA
mode.
If --no-huge and --iova-mode=PA is requested error out as this is
an impossible configuration.
Signed-off-by: David Wilder <dwil...@us.ibm.com>
---
lib/librte_eal/linux/eal/eal.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/lib/librte_eal/linux/eal/eal.c
b/lib/librte_eal/linux/eal/eal.c
index 9530ee55f..d3a0a1731 100644
--- a/lib/librte_eal/linux/eal/eal.c
+++ b/lib/librte_eal/linux/eal/eal.c
@@ -1062,9 +1062,16 @@ rte_eal_init(int argc, char **argv)
/* if no EAL option "--iova-mode=<pa|va>", use bus IOVA scheme
*/
if (internal_config.iova_mode == RTE_IOVA_DC) {
+
/* autodetect the IOVA mapping mode */
enum rte_iova_mode iova_mode =
rte_bus_get_iommu_class();
+ if (iova_mode == RTE_IOVA_PA &&
!rte_eal_has_hugepages()) {
+ iova_mode = RTE_IOVA_VA;
What if igb_uio or vfio_nommu has been loaded(i.e no iommu support
enabled from the driver)? This would fail.
Yes they would fail. If igb_uio or vfio_nommu (or any driver) cant be
forced to VA mode it cant be used with out hugepages. Drivers can be
available but not used therefor we print a warning message.
+ RTE_LOG(WARNING, EAL, "Some buses want 'PA'
but forcing 'VA' because --no-huge is requested.\n");
+ RTE_LOG(WARNING, EAL, "Not all buses may be
able to initialize.\n");
+ }
+
if (iova_mode == RTE_IOVA_DC) {
RTE_LOG(DEBUG, EAL, "Buses did not request a
specific IOVA mode.\n");
@@ -1111,6 +1118,13 @@ rte_eal_init(int argc, char **argv)
internal_config.iova_mode;
}
+ if (rte_eal_iova_mode() == RTE_IOVA_PA &&
+ rte_eal_has_hugepages() == 0) {
+ rte_eal_init_alert("Cannot use IOVA as 'PA' with
--no-huge");
Top of the tree already detecting this case. am I missing anything?
[master]dell[dpdk.org] $ sudo ./build/app/test/dpdk-test -c 0x3
--no-huge --iova-mode=pa
EAL: Detected 56 lcore(s)
EAL: Detected 2 NUMA nodes
EAL: Static memory layout is selected, amount of reserved memory can
be adjusted with -m or --socket-mem
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
EAL: FATAL: Cannot use IOVA as 'PA' since physical addresses are not
available
EAL: Cannot use IOVA as 'PA' since physical addresses are not available
The check you reference is reporting that physical address are not
available, for example no permissions to read /proc/self/pagemap. In
this case, if --no-huge is set then PA mode is not allowed. There is no
guarantee that physical address are persistent with out using hugepages.
+ rte_errno = EINVAL;
+ return -1;
+ }
+
if (rte_eal_iova_mode() == RTE_IOVA_PA && !phys_addrs) {
rte_eal_init_alert("Cannot use IOVA as 'PA' since
physical addresses are not available");
rte_errno = EINVAL;
--
2.25.0
