[bpf-next PATCH] bpf: sockmap, test tool support to skip cgroup arg

[John Fastabend]

Its handy to not have to setup a cgroup environment when running
test_sockmap with user specified options. This patch setups a cgroup
environment, similar to how it is done with the auto test suite, when
the user does not provide a cgroup arg.

Signed-off-by: John Fastabend <john.fastab...@gmail.com>
---
 tools/testing/selftests/bpf/test_sockmap.c |   24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_sockmap.c 
b/tools/testing/selftests/bpf/test_sockmap.c
index 3845144e2c91..11dfb1f10e15 100644
--- a/tools/testing/selftests/bpf/test_sockmap.c
+++ b/tools/testing/selftests/bpf/test_sockmap.c
@@ -1734,6 +1734,7 @@ int main(int argc, char **argv)
        int opt, longindex, err, cg_fd = 0;
        char *bpf_file = BPF_SOCKMAP_FILENAME;
        int test = PING_PONG;
+       bool cleanup = true;
 
        if (argc < 2)
                return test_suite(-1);
@@ -1773,6 +1774,7 @@ int main(int argc, char **argv)
                                        cg_fd, optarg);
                                return cg_fd;
                        }
+                       cleanup = false;
                        break;
                case 'r':
                        rate = atoi(optarg);
@@ -1818,9 +1820,23 @@ int main(int argc, char **argv)
                return test_suite(cg_fd);
 
        if (!cg_fd) {
-               fprintf(stderr, "%s requires cgroup option: --cgroup <path>\n",
-                       argv[0]);
-               return -1;
+               if (setup_cgroup_environment()) {
+                       fprintf(stderr, "ERROR: cgroup env failed\n");
+                       return -EINVAL;
+               }
+
+               cg_fd = create_and_get_cgroup(CG_PATH);
+               if (cg_fd < 0) {
+                       fprintf(stderr,
+                               "ERROR: (%i) open cg path failed: %s\n",
+                               cg_fd, optarg);
+                       return cg_fd;
+               }
+
+               if (join_cgroup(CG_PATH)) {
+                       fprintf(stderr, "ERROR: failed to join cgroup\n");
+                       return -EINVAL;
+               }
        }
 
        err = populate_progs(bpf_file);
@@ -1839,6 +1855,8 @@ int main(int argc, char **argv)
        options.rate = rate;
 
        err = run_options(&options, cg_fd, test);
+       if (cleanup)
+               cleanup_cgroup_environment();
        close(cg_fd);
        return err;
 }