[dpdk-dev] [PATCH v4 16/20] eal: make --no-huge use mmap instead of malloc

[Anatoly Burakov]

This makes it possible to run DPDK without hugepage memory when VFIO
is used, as VFIO uses virtual addresses to set up DMA mappings.

Technically, malloc is just fine, but we want to guarantee that
memory will be page-aligned, so using mmap to be safe.

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
---
 lib/librte_eal/linuxapp/eal/eal_memory.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
index 8d1edd9..315214b 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -1031,7 +1031,13 @@ rte_eal_hugepage_init(void)
 
 	/* hugetlbfs can be disabled */
 	if (internal_config.no_hugetlbfs) {
-		addr = malloc(internal_config.memory);
+		addr = mmap(NULL, internal_config.memory, PROT_READ | PROT_WRITE,
+				MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+		if (addr == MAP_FAILED) {
+			RTE_LOG(ERR, EAL, "%s: mmap() failed: %s\n", __func__,
+					strerror(errno));
+			return -1;
+		}
 		mcfg->memseg[0].phys_addr = (phys_addr_t)(uintptr_t)addr;
 		mcfg->memseg[0].addr = addr;
 		mcfg->memseg[0].len = internal_config.memory;
-- 
1.8.1.4