From 19526e701ea096d13ebf881d32511e567dc41557 Mon Sep 17 00:00:00 2001 From: Wang Yufen Date: Fri, 14 Oct 2022 16:31:13 +0800 Subject: bpftool: Add autoattach for bpf prog load|loadall Add autoattach optional to support one-step load-attach-pin_link. For example, $ bpftool prog loadall test.o /sys/fs/bpf/test autoattach $ bpftool link 26: tracing name test1 tag f0da7d0058c00236 gpl loaded_at 2022-09-09T21:39:49+0800 uid 0 xlated 88B jited 55B memlock 4096B map_ids 3 btf_id 55 28: kprobe name test3 tag 002ef1bef0723833 gpl loaded_at 2022-09-09T21:39:49+0800 uid 0 xlated 88B jited 56B memlock 4096B map_ids 3 btf_id 55 57: tracepoint name oncpu tag 7aa55dfbdcb78941 gpl loaded_at 2022-09-09T21:41:32+0800 uid 0 xlated 456B jited 265B memlock 4096B map_ids 17,13,14,15 btf_id 82 $ bpftool link 1: tracing prog 26 prog_type tracing attach_type trace_fentry 3: perf_event prog 28 10: perf_event prog 57 The autoattach optional can support tracepoints, k(ret)probes, u(ret)probes. Signed-off-by: Wei Yongjun Signed-off-by: Wang Yufen Link: https://lore.kernel.org/r/1665736275-28143-2-git-send-email-wangyufen@huawei.com Signed-off-by: Alexei Starovoitov --- tools/bpf/bpftool/prog.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 74 insertions(+), 2 deletions(-) (limited to 'tools/bpf') diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index c81362a001ba..10ec29cb4598 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -1453,6 +1453,67 @@ get_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, return ret; } +static int +auto_attach_program(struct bpf_program *prog, const char *path) +{ + struct bpf_link *link; + int err; + + link = bpf_program__attach(prog); + if (!link) { + p_info("Program %s does not support autoattach, falling back to pinning", + bpf_program__name(prog)); + return bpf_obj_pin(bpf_program__fd(prog), path); + } + + err = bpf_link__pin(link, path); + bpf_link__destroy(link); + return err; +} + +static int pathname_concat(char *buf, size_t buf_sz, const char *path, const char *name) +{ + int len; + + len = snprintf(buf, buf_sz, "%s/%s", path, name); + if (len < 0) + return -EINVAL; + if ((size_t)len >= buf_sz) + return -ENAMETOOLONG; + + return 0; +} + +static int +auto_attach_programs(struct bpf_object *obj, const char *path) +{ + struct bpf_program *prog; + char buf[PATH_MAX]; + int err; + + bpf_object__for_each_program(prog, obj) { + err = pathname_concat(buf, sizeof(buf), path, bpf_program__name(prog)); + if (err) + goto err_unpin_programs; + + err = auto_attach_program(prog, buf); + if (err) + goto err_unpin_programs; + } + + return 0; + +err_unpin_programs: + while ((prog = bpf_object__prev_program(obj, prog))) { + if (pathname_concat(buf, sizeof(buf), path, bpf_program__name(prog))) + continue; + + bpf_program__unpin(prog, buf); + } + + return err; +} + static int load_with_options(int argc, char **argv, bool first_prog_only) { enum bpf_prog_type common_prog_type = BPF_PROG_TYPE_UNSPEC; @@ -1464,6 +1525,7 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) struct bpf_program *prog = NULL, *pos; unsigned int old_map_fds = 0; const char *pinmaps = NULL; + bool auto_attach = false; struct bpf_object *obj; struct bpf_map *map; const char *pinfile; @@ -1583,6 +1645,9 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) goto err_free_reuse_maps; pinmaps = GET_ARG(); + } else if (is_prefix(*argv, "autoattach")) { + auto_attach = true; + NEXT_ARG(); } else { p_err("expected no more arguments, 'type', 'map' or 'dev', got: '%s'?", *argv); @@ -1692,14 +1757,20 @@ static int load_with_options(int argc, char **argv, bool first_prog_only) goto err_close_obj; } - err = bpf_obj_pin(bpf_program__fd(prog), pinfile); + if (auto_attach) + err = auto_attach_program(prog, pinfile); + else + err = bpf_obj_pin(bpf_program__fd(prog), pinfile); if (err) { p_err("failed to pin program %s", bpf_program__section_name(prog)); goto err_close_obj; } } else { - err = bpf_object__pin_programs(obj, pinfile); + if (auto_attach) + err = auto_attach_programs(obj, pinfile); + else + err = bpf_object__pin_programs(obj, pinfile); if (err) { p_err("failed to pin all programs"); goto err_close_obj; @@ -2338,6 +2409,7 @@ static int do_help(int argc, char **argv) " [type TYPE] [dev NAME] \\\n" " [map { idx IDX | name NAME } MAP]\\\n" " [pinmaps MAP_DIR]\n" + " [autoattach]\n" " %1$s %2$s attach PROG ATTACH_TYPE [MAP]\n" " %1$s %2$s detach PROG ATTACH_TYPE [MAP]\n" " %1$s %2$s run PROG \\\n" -- cgit v1.2.3