From 43cb8cbadffa21e88a65dd1129c86f5552d6c42e Mon Sep 17 00:00:00 2001 From: Hao Luo Date: Tue, 16 Aug 2022 16:40:11 -0700 Subject: libbpf: Allows disabling auto attach Adds libbpf APIs for disabling auto-attach for individual functions. This is motivated by the use case of cgroup iter [1]. Some iter types require their parameters to be non-zero, therefore applying auto-attach on them will fail. With these two new APIs, users who want to use auto-attach and these types of iters can disable auto-attach on the program and perform manual attach. [1] https://lore.kernel.org/bpf/CAEf4BzZ+a2uDo_t6kGBziqdz--m2gh2_EUwkGLDtMd65uwxUjA@mail.gmail.com/ Signed-off-by: Hao Luo Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20220816234012.910255-1-haoluo@google.com --- tools/lib/bpf/libbpf.c | 15 ++++++++++++++- tools/lib/bpf/libbpf.h | 2 ++ tools/lib/bpf/libbpf.map | 2 ++ 3 files changed, 18 insertions(+), 1 deletion(-) (limited to 'tools/lib') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index aa05a99b913d..0159a43c7efd 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -417,6 +417,7 @@ struct bpf_program { int fd; bool autoload; + bool autoattach; bool mark_btf_static; enum bpf_prog_type type; enum bpf_attach_type expected_attach_type; @@ -755,6 +756,8 @@ bpf_object__init_prog(struct bpf_object *obj, struct bpf_program *prog, prog->autoload = true; } + prog->autoattach = true; + /* inherit object's log_level */ prog->log_level = obj->log_level; @@ -8314,6 +8317,16 @@ int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) return 0; } +bool bpf_program__autoattach(const struct bpf_program *prog) +{ + return prog->autoattach; +} + +void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach) +{ + prog->autoattach = autoattach; +} + const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog) { return prog->insns; @@ -12346,7 +12359,7 @@ int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) struct bpf_program *prog = *s->progs[i].prog; struct bpf_link **link = s->progs[i].link; - if (!prog->autoload) + if (!prog->autoload || !prog->autoattach) continue; /* auto-attaching not supported for this program */ diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 61493c4cddac..88a1ac34b12a 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -260,6 +260,8 @@ LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog); LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog); LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload); +LIBBPF_API bool bpf_program__autoattach(const struct bpf_program *prog); +LIBBPF_API void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach); struct bpf_insn; diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 119e6e1ea7f1..2b928dc21af0 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -358,6 +358,8 @@ LIBBPF_1.0.0 { bpf_obj_get_opts; bpf_prog_query_opts; bpf_program__attach_ksyscall; + bpf_program__autoattach; + bpf_program__set_autoattach; btf__add_enum64; btf__add_enum64_value; libbpf_bpf_attach_type_str; -- cgit v1.2.3