[dpdk-stable] [PATCH v1 1/2] lib/timer: protect timer subsystem initialized with lock

[Phil Yang <phil.yang@arm.com>]

From: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>

rte_timer_subsystem_initialized is a global variable that can be
accessed by multiple processes simultaneously. Hence, any access
to rte_timer_subsystem_initialized should be protected by
rte_mcfg_timer_lock.

Fixes: f9d6cd8bfe9e ("timer: fix resource leak in finalize")
Cc: stable@dpdk.org

Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Phil Yang <phil.yang@arm.com>
---
 lib/librte_timer/rte_timer.c | 24 ++++++++++++++----------
 1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/lib/librte_timer/rte_timer.c b/lib/librte_timer/rte_timer.c
index 89f2707..269e921 100644
--- a/lib/librte_timer/rte_timer.c
+++ b/lib/librte_timer/rte_timer.c
@@ -145,11 +145,13 @@ rte_timer_subsystem_init(void)
 	const size_t mem_size = data_arr_size + sizeof(*rte_timer_mz_refcnt);
 	bool do_full_init = true;
 
-	if (rte_timer_subsystem_initialized)
-		return -EALREADY;
-
 	rte_mcfg_timer_lock();
 
+	if (rte_timer_subsystem_initialized) {
+		rte_mcfg_timer_unlock();
+		return -EALREADY;
+	}
+
 	mz = rte_memzone_lookup(mz_name);
 	if (mz == NULL) {
 		mz = rte_memzone_reserve_aligned(mz_name, mem_size,
@@ -183,27 +185,29 @@ rte_timer_subsystem_init(void)
 	rte_timer_data_arr[default_data_id].internal_flags |= FL_ALLOCATED;
 	(*rte_timer_mz_refcnt)++;
 
-	rte_mcfg_timer_unlock();
-
 	rte_timer_subsystem_initialized = 1;
 
+	rte_mcfg_timer_unlock();
+
 	return 0;
 }
 
 void
 rte_timer_subsystem_finalize(void)
 {
-	if (!rte_timer_subsystem_initialized)
-		return;
-
 	rte_mcfg_timer_lock();
 
+	if (!rte_timer_subsystem_initialized) {
+		rte_mcfg_timer_unlock();
+		return;
+	}
+
 	if (--(*rte_timer_mz_refcnt) == 0)
 		rte_memzone_free(rte_timer_data_mz);
 
-	rte_mcfg_timer_unlock();
-
 	rte_timer_subsystem_initialized = 0;
+
+	rte_mcfg_timer_unlock();
 }
 
 /* Initialize the timer handle tim for use */
-- 
2.7.4