diff options
Diffstat (limited to 'tools/tracing/rtla/src/utils.c')
-rw-r--r-- | tools/tracing/rtla/src/utils.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c index 3e25f0277fb9..623a38908ed5 100644 --- a/tools/tracing/rtla/src/utils.c +++ b/tools/tracing/rtla/src/utils.c @@ -626,6 +626,64 @@ static int get_self_cgroup(char *self_cg, int sizeof_self_cg) return 1; } +/* + * set_comm_cgroup - Set cgroup to pid_t pid + * + * If cgroup argument is not NULL, the threads will move to the given cgroup. + * Otherwise, the cgroup of the calling, i.e., rtla, thread will be used. + * + * Supports cgroup v2. + * + * Returns 1 on success, 0 otherwise. + */ +int set_pid_cgroup(pid_t pid, const char *cgroup) +{ + char cgroup_path[MAX_PATH - strlen("/cgroup.procs")]; + char cgroup_procs[MAX_PATH]; + char pid_str[24]; + int retval; + int cg_fd; + + retval = find_mount("cgroup2", cgroup_path, sizeof(cgroup_path)); + if (!retval) { + err_msg("Did not find cgroupv2 mount point\n"); + return 0; + } + + if (!cgroup) { + retval = get_self_cgroup(&cgroup_path[strlen(cgroup_path)], + sizeof(cgroup_path) - strlen(cgroup_path)); + if (!retval) { + err_msg("Did not find self cgroup\n"); + return 0; + } + } else { + snprintf(&cgroup_path[strlen(cgroup_path)], + sizeof(cgroup_path) - strlen(cgroup_path), "%s/", cgroup); + } + + snprintf(cgroup_procs, MAX_PATH, "%s/cgroup.procs", cgroup_path); + + debug_msg("Using cgroup path at: %s\n", cgroup_procs); + + cg_fd = open(cgroup_procs, O_RDWR); + if (cg_fd < 0) + return 0; + + snprintf(pid_str, sizeof(pid_str), "%d\n", pid); + + retval = write(cg_fd, pid_str, strlen(pid_str)); + if (retval < 0) + err_msg("Error setting cgroup attributes for pid:%s - %s\n", + pid_str, strerror(errno)); + else + debug_msg("Set cgroup attributes for pid:%s\n", pid_str); + + close(cg_fd); + + return (retval >= 0); +} + /** * set_comm_cgroup - Set cgroup to threads starting with char *comm_prefix * |