diff options
Diffstat (limited to 'tools/testing/selftests/bpf/cgroup_helpers.c')
| -rw-r--r-- | tools/testing/selftests/bpf/cgroup_helpers.c | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/cgroup_helpers.c b/tools/testing/selftests/bpf/cgroup_helpers.c index f3bca3ade0f3..c87b4e052ce9 100644 --- a/tools/testing/selftests/bpf/cgroup_helpers.c +++ b/tools/testing/selftests/bpf/cgroup_helpers.c @@ -6,6 +6,7 @@ #include <sys/types.h> #include <linux/limits.h> #include <stdio.h> +#include <stdlib.h> #include <linux/sched.h> #include <fcntl.h> #include <unistd.h> @@ -176,3 +177,59 @@ int create_and_get_cgroup(char *path) return fd; } + +/** + * get_cgroup_id() - Get cgroup id for a particular cgroup path + * @path: The cgroup path, relative to the workdir, to join + * + * On success, it returns the cgroup id. On failure it returns 0, + * which is an invalid cgroup id. + * If there is a failure, it prints the error to stderr. + */ +unsigned long long get_cgroup_id(char *path) +{ + int dirfd, err, flags, mount_id, fhsize; + union { + unsigned long long cgid; + unsigned char raw_bytes[8]; + } id; + char cgroup_workdir[PATH_MAX + 1]; + struct file_handle *fhp, *fhp2; + unsigned long long ret = 0; + + format_cgroup_path(cgroup_workdir, path); + + dirfd = AT_FDCWD; + flags = 0; + fhsize = sizeof(*fhp); + fhp = calloc(1, fhsize); + if (!fhp) { + log_err("calloc"); + return 0; + } + err = name_to_handle_at(dirfd, cgroup_workdir, fhp, &mount_id, flags); + if (err >= 0 || fhp->handle_bytes != 8) { + log_err("name_to_handle_at"); + goto free_mem; + } + + fhsize = sizeof(struct file_handle) + fhp->handle_bytes; + fhp2 = realloc(fhp, fhsize); + if (!fhp2) { + log_err("realloc"); + goto free_mem; + } + err = name_to_handle_at(dirfd, cgroup_workdir, fhp2, &mount_id, flags); + fhp = fhp2; + if (err < 0) { + log_err("name_to_handle_at"); + goto free_mem; + } + + memcpy(id.raw_bytes, fhp->f_handle, 8); + ret = id.cgid; + +free_mem: + free(fhp); + return ret; +} |