diff options
author | He Zhe <zhe.he@windriver.com> | 2019-08-02 16:29:51 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-29 08:26:41 +0200 |
commit | 5411aefc01894b274ed7c3c20fbbf36e38540363 (patch) | |
tree | 96b0fd80f324963b104cb628a9d93616e7ad6f99 /tools/perf | |
parent | 93a6504dda134b18b8b16d40d38a4bff8ace5978 (diff) |
perf ftrace: Fix failure to set cpumask when only one cpu is present
[ Upstream commit cf30ae726c011e0372fd4c2d588466c8b50a8907 ]
The buffer containing the string used to set cpumask is overwritten at
the end of the string later in cpu_map__snprint_mask due to not enough
memory space, when there is only one cpu.
And thus causes the following failure:
$ perf ftrace ls
failed to reset ftrace
$
This patch fixes the calculation of the cpumask string size.
Signed-off-by: He Zhe <zhe.he@windriver.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Fixes: dc23103278c5 ("perf ftrace: Add support for -a and -C option")
Link: http://lkml.kernel.org/r/1564734592-15624-1-git-send-email-zhe.he@windriver.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/builtin-ftrace.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c index 25a42acabee1..13a33fb71a6d 100644 --- a/tools/perf/builtin-ftrace.c +++ b/tools/perf/builtin-ftrace.c @@ -162,7 +162,7 @@ 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); |