Hi Naresh,

On 11/21/2018 06:53 PM, Y Song wrote:

On Wed, Nov 21, 2018 at 3:44 AM Naresh Kamboju naresh.kamboju@linaro.org wrote:

...

Kselftest bpf get_cgroup_id_user is failed on all devices.

selftests: bpf: get_cgroup_id_user main:PASS:setup_cgroup_environment main:PASS:create_and_get_cgroup main:PASS:join_cgroup main:PASS:bpf_prog_load main:PASS:bpf_find_map main:PASS:bpf_find_map main:FAIL:open err -1 errno 2 not ok 1..15 selftests: bpf: get_cgroup_id_user [FAIL]

The strace output shows, This expected file not found, "/sys/kernel/debug/tracing/events/syscalls/sys_enter_nanosleep/id"

bpf(BPF_MAP_UPDATE_ELEM, {map_fd=5, key=0x7fff0c68c138, value=0x7fff0c68c13c, flags=BPF_ANY}, 72) = 0 open("/sys/kernel/debug/tracing/events/syscalls/sys_enter_nanosleep/id", O_RDONLY) = -1 ENOENT (No such file or directory) write(1, "main:FAIL:open err -1 errno 2\n", 30main:FAIL:open err -1 errno 2

Am I missing any pre-requirement ?

You probably miss kernel config CONFIG_FTRACE_SYSCALLS.

If that does the trick for you, could you add that to the BPF kselftest config snippet?

Thanks, Daniel