perf ftrace: Fix failure to set cpumask when only one cpu is present

[linux-2.6-microblaze.git] / tools / perf / builtin-ftrace.c

diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 66d5a66..0193128 100644 (file)
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -173,7 +173,7 @@ static int set_tracing_cpumask(struct cpu_map *cpumap)
        int last_cpu;
 
        last_cpu = cpu_map__cpu(cpumap, cpumap->nr - 1);
-       mask_size = (last_cpu + 3) / 4 + 1;
+       mask_size = last_cpu / 4 + 2; /* one more byte for EOS */
        mask_size += last_cpu / 32; /* ',' is needed for every 32th cpus */
 
        cpumask = malloc(mask_size);