[dpdk-stable] [PATCH v7 1/1] fbarray: fix duplicated fbarray file in secondary

[yasufum.o@gmail.com]

From: Yasufumi Ogawa <ogawa.yasufumi@lab.ntt.co.jp>

In secondary_msl_create_walk(), it creates a file for fbarrays with its
PID for reserving unique name among secondary processes. However, it
does not work if several secondaries run as app containers because each
of containerized secondary has PID 1, and failed to reserve unique name
other than first one. To reserve unique name in each of containers, use
hostname in addition to PID.

Cc: stable@dpdk.org

Signed-off-by: Yasufumi Ogawa <yasufum.o@gmail.com>
---
 lib/librte_eal/linux/eal/eal_memalloc.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/lib/librte_eal/linux/eal/eal_memalloc.c b/lib/librte_eal/linux/eal/eal_memalloc.c
index af6d0d023..11de6d4d6 100644
--- a/lib/librte_eal/linux/eal/eal_memalloc.c
+++ b/lib/librte_eal/linux/eal/eal_memalloc.c
@@ -1365,6 +1365,12 @@ secondary_msl_create_walk(const struct rte_memseg_list *msl,
 	struct rte_memseg_list *primary_msl, *local_msl;
 	char name[PATH_MAX];
 	int msl_idx, ret;
+	char hostname[HOST_NAME_MAX+1] = { 0 };
+	/* filename of secondary's fbarray is defined such as
+	 * "fbarray_memseg-1048576k-0-0_PID_HOSTNAME" and length of PID
+	 * can be 7 digits maximumly.
+	 */
+	int fbarray_sec_name_len = 32 + 7 + 1 + HOST_NAME_MAX + 1;
 
 	if (msl->external)
 		return 0;
@@ -1373,9 +1379,13 @@ secondary_msl_create_walk(const struct rte_memseg_list *msl,
 	primary_msl = &mcfg->memsegs[msl_idx];
 	local_msl = &local_memsegs[msl_idx];
 
-	/* create distinct fbarrays for each secondary */
-	snprintf(name, RTE_FBARRAY_NAME_LEN, "%s_%i",
-		primary_msl->memseg_arr.name, getpid());
+	/* Create distinct fbarrays for each secondary by using PID and
+	 * hostname. The reason why using hostname is because PID could be
+	 * duplicated among secondaries if it is launched in a container.
+	 */
+	gethostname(hostname, sizeof(hostname));
+	snprintf(name, fbarray_sec_name_len, "%s_%d_%s",
+			primary_msl->memseg_arr.name, (int)getpid(), hostname);
 
 	ret = rte_fbarray_init(&local_msl->memseg_arr, name,
 		primary_msl->memseg_arr.len,
-- 
2.17.1