diff options
Diffstat (limited to 'tools/bpf/bpftool/cgroup.c')
| -rw-r--r-- | tools/bpf/bpftool/cgroup.c | 170 |
1 files changed, 165 insertions, 5 deletions
diff --git a/tools/bpf/bpftool/cgroup.c b/tools/bpf/bpftool/cgroup.c index 16bee011e16c..ee7a9765c6b3 100644 --- a/tools/bpf/bpftool/cgroup.c +++ b/tools/bpf/bpftool/cgroup.c @@ -2,7 +2,12 @@ // Copyright (C) 2017 Facebook // Author: Roman Gushchin <guro@fb.com> +#define _XOPEN_SOURCE 500 +#include <errno.h> #include <fcntl.h> +#include <ftw.h> +#include <mntent.h> +#include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> @@ -53,7 +58,8 @@ static enum bpf_attach_type parse_attach_type(const char *str) } static int show_bpf_prog(int id, const char *attach_type_str, - const char *attach_flags_str) + const char *attach_flags_str, + int level) { struct bpf_prog_info info = {}; __u32 info_len = sizeof(info); @@ -78,7 +84,8 @@ static int show_bpf_prog(int id, const char *attach_type_str, jsonw_string_field(json_wtr, "name", info.name); jsonw_end_object(json_wtr); } else { - printf("%-8u %-15s %-15s %-15s\n", info.id, + printf("%s%-8u %-15s %-15s %-15s\n", level ? " " : "", + info.id, attach_type_str, attach_flags_str, info.name); @@ -88,7 +95,20 @@ static int show_bpf_prog(int id, const char *attach_type_str, return 0; } -static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type) +static int count_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type) +{ + __u32 prog_cnt = 0; + int ret; + + ret = bpf_prog_query(cgroup_fd, type, 0, NULL, NULL, &prog_cnt); + if (ret) + return -1; + + return prog_cnt; +} + +static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type, + int level) { __u32 prog_ids[1024] = {0}; char *attach_flags_str; @@ -123,7 +143,7 @@ static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type) for (iter = 0; iter < prog_cnt; iter++) show_bpf_prog(prog_ids[iter], attach_type_strings[type], - attach_flags_str); + attach_flags_str, level); return 0; } @@ -161,7 +181,7 @@ static int do_show(int argc, char **argv) * If we were able to get the show for at least one * attach type, let's return 0. */ - if (show_attached_bpf_progs(cgroup_fd, type) == 0) + if (show_attached_bpf_progs(cgroup_fd, type, 0) == 0) ret = 0; } @@ -173,6 +193,143 @@ exit: return ret; } +/* + * To distinguish nftw() errors and do_show_tree_fn() errors + * and avoid duplicating error messages, let's return -2 + * from do_show_tree_fn() in case of error. + */ +#define NFTW_ERR -1 +#define SHOW_TREE_FN_ERR -2 +static int do_show_tree_fn(const char *fpath, const struct stat *sb, + int typeflag, struct FTW *ftw) +{ + enum bpf_attach_type type; + bool skip = true; + int cgroup_fd; + + if (typeflag != FTW_D) + return 0; + + cgroup_fd = open(fpath, O_RDONLY); + if (cgroup_fd < 0) { + p_err("can't open cgroup %s: %s", fpath, strerror(errno)); + return SHOW_TREE_FN_ERR; + } + + for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) { + int count = count_attached_bpf_progs(cgroup_fd, type); + + if (count < 0 && errno != EINVAL) { + p_err("can't query bpf programs attached to %s: %s", + fpath, strerror(errno)); + close(cgroup_fd); + return SHOW_TREE_FN_ERR; + } + if (count > 0) { + skip = false; + break; + } + } + + if (skip) { + close(cgroup_fd); + return 0; + } + + if (json_output) { + jsonw_start_object(json_wtr); + jsonw_string_field(json_wtr, "cgroup", fpath); + jsonw_name(json_wtr, "programs"); + jsonw_start_array(json_wtr); + } else { + printf("%s\n", fpath); + } + + for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) + show_attached_bpf_progs(cgroup_fd, type, ftw->level); + + if (json_output) { + jsonw_end_array(json_wtr); + jsonw_end_object(json_wtr); + } + + close(cgroup_fd); + + return 0; +} + +static char *find_cgroup_root(void) +{ + struct mntent *mnt; + FILE *f; + + f = fopen("/proc/mounts", "r"); + if (f == NULL) + return NULL; + + while ((mnt = getmntent(f))) { + if (strcmp(mnt->mnt_type, "cgroup2") == 0) { + fclose(f); + return strdup(mnt->mnt_dir); + } + } + + fclose(f); + return NULL; +} + +static int do_show_tree(int argc, char **argv) +{ + char *cgroup_root; + int ret; + + switch (argc) { + case 0: + cgroup_root = find_cgroup_root(); + if (!cgroup_root) { + p_err("cgroup v2 isn't mounted"); + return -1; + } + break; + case 1: + cgroup_root = argv[0]; + break; + default: + p_err("too many parameters for cgroup tree"); + return -1; + } + + + if (json_output) + jsonw_start_array(json_wtr); + else + printf("%s\n" + "%-8s %-15s %-15s %-15s\n", + "CgroupPath", + "ID", "AttachType", "AttachFlags", "Name"); + + switch (nftw(cgroup_root, do_show_tree_fn, 1024, FTW_MOUNT)) { + case NFTW_ERR: + p_err("can't iterate over %s: %s", cgroup_root, + strerror(errno)); + ret = -1; + break; + case SHOW_TREE_FN_ERR: + ret = -1; + break; + default: + ret = 0; + } + + if (json_output) + jsonw_end_array(json_wtr); + + if (argc == 0) + free(cgroup_root); + + return ret; +} + static int do_attach(int argc, char **argv) { enum bpf_attach_type attach_type; @@ -289,6 +446,7 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %s %s { show | list } CGROUP\n" + " %s %s tree [CGROUP_ROOT]\n" " %s %s attach CGROUP ATTACH_TYPE PROG [ATTACH_FLAGS]\n" " %s %s detach CGROUP ATTACH_TYPE PROG\n" " %s %s help\n" @@ -298,6 +456,7 @@ static int do_help(int argc, char **argv) " " HELP_SPEC_PROGRAM "\n" " " HELP_SPEC_OPTIONS "\n" "", + bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2]); @@ -307,6 +466,7 @@ static int do_help(int argc, char **argv) static const struct cmd cmds[] = { { "show", do_show }, { "list", do_show }, + { "tree", do_show_tree }, { "attach", do_attach }, { "detach", do_detach }, { "help", do_help }, |