[dpdk-dev] [PATCH v2 1/3] test: disable no-huge test with PA IOVA

[Stanislaw Kardach <kda@semihalf.com>]

On Linux systems without IOMMU support available (be it lack of
supported IOMMU or lack of IOMMU support in kernel or explicit --no-huge
EAL parameter), the IOVA mapping will default to DMA with physical
addresses. This implicitly requires hugepage support to work (checked in
rte_eal_using_phys_addrs).
Therefore trying to run the eal_flags_no_huge_autotest in such scenario
is not a valid requirement. This issue was discovered on RISC-V arch.

To verify this even on x86 do (output from i5-10210U):

$ ./app/test/dpdk-test -m 18 --iova-mode=pa --no-huge
EAL: Detected 8 lcore(s)
EAL: Detected 1 NUMA nodes
EAL: Detected static linkage of DPDK
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
EAL: FATAL: Cannot use IOVA as 'PA' since physical addresses are not ...
EAL: Cannot use IOVA as 'PA' since physical addresses are not available

While doing:

$ sudo ./app/test/dpdk-test --iova-mode=pa
EAL: Detected 8 lcore(s)
EAL: Detected 1 NUMA nodes
EAL: Detected static linkage of DPDK
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
EAL: Selected IOVA mode 'PA'
EAL: No available 1048576 kB hugepages reported
EAL: Probing VFIO support...
EAL: VFIO support initialized
TELEMETRY: No legacy callbacks, legacy socket not created
APP: HPET is not enabled, using TSC as default timer
RTE>>

This commit finishes the above test early with SKIP status to signify
that no-huge support is simply not available.

Signed-off-by: Stanislaw Kardach <kda@semihalf.com>
---
 app/test/test_eal_flags.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/app/test/test_eal_flags.c b/app/test/test_eal_flags.c
index 932fbe3d08..462dc63842 100644
--- a/app/test/test_eal_flags.c
+++ b/app/test/test_eal_flags.c
@@ -756,6 +756,15 @@ test_no_huge_flag(void)
 #else
 	const char * prefix = "--file-prefix=nohuge";
 #endif
+#ifdef RTE_EXEC_ENV_LINUX
+	/* EAL requires hugepages for RTE_IOVA_PA operation on linux.
+	 * The test application is run with RTE_IOVA_DC, so if at this point we
+	 * get RTE_IOVA_PA, it means that newly spawned process will also get
+	 * it.
+	 */
+	if (rte_eal_iova_mode() == RTE_IOVA_PA)
+		return TEST_SKIPPED;
+#endif
 
 	/* With --no-huge */
 	const char *argv1[] = {prgname, prefix, no_huge};
-- 
2.27.0