[dpdk-dev] [PATCH v2] timer: fix resource leak in finalize

[Erik Gabriel Carrillo]

The finalize function should free the memzone created in the init
function, rather than freeing the allocation the memzone references,
otherwise a memzone descriptor can be leaked.

Fixes: c0749f7096c7 ("timer: allow management in shared memory")

Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo at intel.com>
---
changes in v2:
 - Handle scenario where primary process exits before secondaries such
   that memzone is not freed early (Anatoly)

 lib/librte_timer/rte_timer.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index eb46009..4771287 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -60,6 +60,8 @@ struct rte_timer_data {
 };
 
 #define RTE_MAX_DATA_ELS 64
+static const struct rte_memzone *rte_timer_data_mz;
+static rte_atomic16_t *rte_timer_mz_refcnt;
 static struct rte_timer_data *rte_timer_data_arr;
 static const uint32_t default_data_id;
 static uint32_t rte_timer_subsystem_initialized;
@@ -155,6 +157,7 @@ rte_timer_subsystem_init_v1905(void)
 	struct rte_timer_data *data;
 	int i, lcore_id;
 	static const char *mz_name = "rte_timer_mz";
+	size_t data_arr_size = RTE_MAX_DATA_ELS * sizeof(*rte_timer_data_arr);
 
 	if (rte_timer_subsystem_initialized)
 		return -EALREADY;
@@ -164,10 +167,14 @@ rte_timer_subsystem_init_v1905(void)
 		if (mz == NULL)
 			return -EEXIST;
 
+		rte_timer_data_mz = mz;
 		rte_timer_data_arr = mz->addr;
+		rte_timer_mz_refcnt =
+				(void *)((char *)mz->addr + data_arr_size);
 
 		rte_timer_data_arr[default_data_id].internal_flags |=
 			FL_ALLOCATED;
+		rte_atomic16_inc(rte_timer_mz_refcnt);
 
 		rte_timer_subsystem_initialized = 1;
 
@@ -175,12 +182,15 @@ rte_timer_subsystem_init_v1905(void)
 	}
 
 	mz = rte_memzone_reserve_aligned(mz_name,
-			RTE_MAX_DATA_ELS * sizeof(*rte_timer_data_arr),
+			data_arr_size + sizeof(*rte_timer_mz_refcnt),
 			SOCKET_ID_ANY, 0, RTE_CACHE_LINE_SIZE);
 	if (mz == NULL)
 		return -ENOMEM;
 
+	rte_timer_data_mz = mz;
 	rte_timer_data_arr = mz->addr;
+	rte_timer_mz_refcnt = (void *)((char *)mz->addr + data_arr_size);
+	rte_atomic16_init(rte_timer_mz_refcnt);
 
 	for (i = 0; i < RTE_MAX_DATA_ELS; i++) {
 		data = &rte_timer_data_arr[i];
@@ -193,6 +203,7 @@ rte_timer_subsystem_init_v1905(void)
 	}
 
 	rte_timer_data_arr[default_data_id].internal_flags |= FL_ALLOCATED;
+	rte_atomic16_inc(rte_timer_mz_refcnt);
 
 	rte_timer_subsystem_initialized = 1;
 
@@ -205,8 +216,11 @@ BIND_DEFAULT_SYMBOL(rte_timer_subsystem_init, _v1905, 19.05);
 void __rte_experimental
 rte_timer_subsystem_finalize(void)
 {
-	if (rte_timer_data_arr)
-		rte_free(rte_timer_data_arr);
+	if (!rte_timer_subsystem_initialized)
+		return;
+
+	if (rte_atomic16_dec_and_test(rte_timer_mz_refcnt))
+		rte_memzone_free(rte_timer_data_mz);
 
 	rte_timer_subsystem_initialized = 0;
 }
-- 
2.6.4