On Tue, Apr 28, 2020 at 11:47 PM Song Liu <songliubraving@xxxxxx> wrote:
>
> Add test for BPF_ENABLE_STATS, which should enable run_time_ns stats.
>
> ~/selftests/bpf# ./test_progs -t enable_stats -v
> test_enable_stats:PASS:skel_open_and_load 0 nsec
> test_enable_stats:PASS:get_stats_fd 0 nsec
> test_enable_stats:PASS:attach_raw_tp 0 nsec
> test_enable_stats:PASS:get_prog_info 0 nsec
> test_enable_stats:PASS:check_stats_enabled 0 nsec
> test_enable_stats:PASS:check_run_cnt_valid 0 nsec
> Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
>
> Signed-off-by: Song Liu <songliubraving@xxxxxx>
> ---
> .../selftests/bpf/prog_tests/enable_stats.c | 46 +++++++++++++++++++
> .../selftests/bpf/progs/test_enable_stats.c | 18 ++++++++
> 2 files changed, 64 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/enable_stats.c
> create mode 100644 tools/testing/selftests/bpf/progs/test_enable_stats.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/enable_stats.c b/tools/testing/selftests/bpf/prog_tests/enable_stats.c
> new file mode 100644
> index 000000000000..cb5e34dcfd42
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/enable_stats.c
> @@ -0,0 +1,46 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <test_progs.h>
> +#include <sys/mman.h>
is this header used for anything?
> +#include "test_enable_stats.skel.h"
> +
> +void test_enable_stats(void)
> +{
[...]
> +
> +char _license[] SEC("license") = "GPL";
> +
> +static __u64 count;
this is actually very unreliable, because compiler might decide to
just remove this variable. It should be either `static volatile`, or
better use zero-initialized global variable:
__u64 count = 0;
> +
> +SEC("raw_tracepoint/sys_enter")
> +int test_enable_stats(void *ctx)
> +{
> + count += 1;
> + return 0;
> +}
> --
> 2.24.1
>
