[dpdk-dev] [RFC] service: stop lcore threads before 'finalize'

[Aaron Conole <aconole@redhat.com>]

I've noticed an occasional segfault from the build system in the
service_autotest and after talking with David (CC'd), it seems like it's
due to the rte_service_finalize deleting the lcore_states object while
active lcores are running.

The below patch is an attempt to solve it by first reassigning all the
lcores back to ROLE_RTE before releasing the memory.  There is probably
a larger question for DPDK proper about actually closing the pending
lcore threads, but that's a separate issue.  I've been running with the
patch for a while, and haven't seen the crash anymore on my system.

Thoughts?  Is it acceptable as-is?
---
diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
index 7e537b8cd2..7d13287bee 100644
--- a/lib/librte_eal/common/rte_service.c
+++ b/lib/librte_eal/common/rte_service.c
@@ -71,6 +71,8 @@ static struct rte_service_spec_impl *rte_services;
 static struct core_state *lcore_states;
 static uint32_t rte_service_library_initialized;
 
+static void service_lcore_uninit(void);
+
 int32_t
 rte_service_init(void)
 {
@@ -122,6 +124,9 @@ rte_service_finalize(void)
 	if (!rte_service_library_initialized)
 		return;
 
+	/* Ensure that all service threads are returned to the ROLE_RTE
+	 */
+	service_lcore_uninit();
 	rte_free(rte_services);
 	rte_free(lcore_states);
 
@@ -897,3 +902,14 @@ rte_service_dump(FILE *f, uint32_t id)
 
 	return 0;
 }
+
+static void service_lcore_uninit(void)
+{
+	unsigned lcore_id;
+	RTE_LCORE_FOREACH(lcore_id) {
+		if (!lcore_states[lcore_id].is_service_core)
+			continue;
+
+		while (rte_service_lcore_del(lcore_id) == -EBUSY);
+	}
+}
---