perf bench numa: Fix cpumask memory leak in node_has_cpus()

Couple numa_allocate_cpumask() and numa_free_cpumask() functions

Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Balamuruhan S <bala24@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
Link: http://lore.kernel.org/lkml/20200813113041.GA1685@oc3871087118.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/bench/numa.c

@@ -248,16 +248,21 @@ static int is_node_present(int node)
 static bool node_has_cpus(int node)
 {
 	struct bitmask *cpu = numa_allocate_cpumask();
+	bool ret = false; /* fall back to nocpus */
 	unsigned int i;
 
-	if (cpu && !numa_node_to_cpus(node, cpu)) {
+	BUG_ON(!cpu);
+	if (!numa_node_to_cpus(node, cpu)) {
 		for (i = 0; i < cpu->size; i++) {
-			if (numa_bitmask_isbitset(cpu, i))
-				return true;
+			if (numa_bitmask_isbitset(cpu, i)) {
+				ret = true;
+				break;
+			}
 		}
 	}
+	numa_free_cpumask(cpu);
 
-	return false; /* lets fall back to nocpus safely */
+	return ret;
 }
 
 static cpu_set_t bind_to_cpu(int target_cpu)