[dpdk-dev] [PATCH v2] mem: warn user when running without NUMA support

[Anatoly Burakov]

Running in non-legacy mode on a NUMA-enabled system without libnuma
is unsupported, so explicitly print out a warning when trying to
do so.

Running in legacy mode without libnuma is still supported whether or
not we are running with libnuma support enabled, so also fix init to
allow that scenario.

Cc: stable at dpdk.org

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
---

Notes:
    v2:
    - Removed unneeded eal_options include that broke the compile

 lib/librte_eal/linux/eal/eal_memalloc.c |  3 +++
 lib/librte_eal/linux/eal/eal_memory.c   | 13 +++++++++++--
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c b/lib/librte_eal/linux/eal/eal_memalloc.c
index b6fb183db..4e83a1a19 100644
--- a/lib/librte_eal/linux/eal/eal_memalloc.c
+++ b/lib/librte_eal/linux/eal/eal_memalloc.c
@@ -725,6 +725,9 @@ alloc_seg(struct rte_memseg *ms, void *addr, int socket_id,
 			__func__, socket_id, cur_socket_id);
 		goto mapped;
 	}
+#else
+	if (rte_socket_count() > 1)
+		RTE_LOG(DEBUG, EAL, "%s(): not checking hugepage NUMA node.\n");
 #endif
 
 	ms->addr = addr;
diff --git a/lib/librte_eal/linux/eal/eal_memory.c b/lib/librte_eal/linux/eal/eal_memory.c
index 1b96b576e..09758e947 100644
--- a/lib/librte_eal/linux/eal/eal_memory.c
+++ b/lib/librte_eal/linux/eal/eal_memory.c
@@ -2088,7 +2088,8 @@ memseg_primary_init_32(void)
 		socket_id = rte_socket_id_by_idx(i);
 
 #ifndef RTE_EAL_NUMA_AWARE_HUGEPAGES
-		if (socket_id > 0)
+		/* we can still sort pages by socket in legacy mode */
+		if (!internal_config.legacy_mem && socket_id > 0)
 			break;
 #endif
 
@@ -2269,7 +2270,8 @@ memseg_primary_init(void)
 			int socket_id = rte_socket_id_by_idx(i);
 
 #ifndef RTE_EAL_NUMA_AWARE_HUGEPAGES
-			if (socket_id > 0)
+			/* we can still sort pages by socket in legacy mode */
+			if (!internal_config.legacy_mem && socket_id > 0)
 				break;
 #endif
 			memtypes[cur_type].page_sz = hugepage_sz;
@@ -2428,6 +2430,13 @@ rte_eal_memseg_init(void)
 	} else {
 		RTE_LOG(ERR, EAL, "Cannot get current resource limits\n");
 	}
+#ifndef RTE_EAL_NUMA_AWARE_HUGEPAGES
+	if (!internal_config.legacy_mem && rte_socket_count() > 1) {
+		RTE_LOG(WARNING, EAL, "DPDK is running on a NUMA system, but is compiled without NUMA support.\n");
+		RTE_LOG(WARNING, EAL, "This will have adverse consequences for performance and usability.\n");
+		RTE_LOG(WARNING, EAL, "Please use --"OPT_LEGACY_MEM" option, or recompile with NUMA support.\n");
+	}
+#endif
 
 	return rte_eal_process_type() == RTE_PROC_PRIMARY ?
 #ifndef RTE_ARCH_64
-- 
2.17.1