We have some tests that assume create_and_get_cgroup returns -1 on error
which is incorrect (it returns 0 on error). Since fd might be zero in
general case, change create_and_get_cgroup to return -1 on error
and fix the users that assume 0 on error.
Fixes: f269099a7e ("tools/bpf: add a selftest for bpf_get_current_cgroup_id() helper")
Fixes: 7d2c6cfc54 ("bpf: use --cgroup in test_suite if supplied")
v2:
- instead of fixing the uses that assume -1 on error, convert the users
that assume 0 on error (fd might be zero in general case)
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
At commit deee2cae27 ("kselftests/bpf: use ping6 as the default ipv6 ping
binary if it exists"), it fixed similar issues for shell script, but it
missed a same issue in the C code.
Fixes: 371e4fcc9d ("selftests/bpf: cgroup local storage-based network counters")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
CC: Philip Li <philip.li@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit adds a bpf kselftest, which demonstrates how percpu
and shared cgroup local storage can be used for efficient lookup-free
network accounting.
Cgroup local storage provides generic memory area with a very efficient
lookup free access. To avoid expensive atomic operations for each
packet, per-cpu cgroup local storage is used. Each packet is initially
charged to a per-cpu counter, and only if the counter reaches certain
value (32 in this case), the charge is moved into the global atomic
counter. This allows to amortize atomic operations, keeping reasonable
accuracy.
The test also implements a naive network traffic throttling, mostly to
demonstrate the possibility of bpf cgroup--based network bandwidth
control.
Expected output:
./test_netcnt
test_netcnt:PASS
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
