| Message ID | 159981836238.134722.1932000789183895507.stgit@toke.dk |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | bpf: Support multi-attach for freplace programs | expand |
On Fri, Sep 11, 2020 at 3:00 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote: > > From: Toke Høiland-Jørgensen <toke@redhat.com> > > This adds support for supplying a target fd and btf ID for the > raw_tracepoint_open() BPF operation, using a new bpf_raw_tracepoint_opts > structure. This can be used for attaching freplace programs to multiple > destinations. > > Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> > --- > tools/lib/bpf/bpf.c | 13 ++++++++++++- > tools/lib/bpf/bpf.h | 9 +++++++++ > tools/lib/bpf/libbpf.map | 1 + > 3 files changed, 22 insertions(+), 1 deletion(-) > > diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c > index 82b983ff6569..25c62993c406 100644 > --- a/tools/lib/bpf/bpf.c > +++ b/tools/lib/bpf/bpf.c > @@ -804,17 +804,28 @@ int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len) > return err; > } > > -int bpf_raw_tracepoint_open(const char *name, int prog_fd) > +int bpf_raw_tracepoint_open_opts(const char *name, int prog_fd, We've had discussion around naming low-level APIs with options and agreed with Andrey Ignatov that we'll follow the _xattr suffix naming for low-level APIs. So let's keep it consistent, I suppose... Please also add bpf_program__attach_trace_opts() for high-level API. > + struct bpf_raw_tracepoint_opts *opts) > { > union bpf_attr attr; > > + if (!OPTS_VALID(opts, bpf_raw_tracepoint_opts)) > + return -EINVAL; > + > memset(&attr, 0, sizeof(attr)); > attr.raw_tracepoint.name = ptr_to_u64(name); > attr.raw_tracepoint.prog_fd = prog_fd; > + attr.raw_tracepoint.tgt_prog_fd = OPTS_GET(opts, tgt_prog_fd, 0); > + attr.raw_tracepoint.tgt_btf_id = OPTS_GET(opts, tgt_btf_id, 0); > > return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); > } > [...]
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 82b983ff6569..25c62993c406 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -804,17 +804,28 @@ int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len) return err; } -int bpf_raw_tracepoint_open(const char *name, int prog_fd) +int bpf_raw_tracepoint_open_opts(const char *name, int prog_fd, + struct bpf_raw_tracepoint_opts *opts) { union bpf_attr attr; + if (!OPTS_VALID(opts, bpf_raw_tracepoint_opts)) + return -EINVAL; + memset(&attr, 0, sizeof(attr)); attr.raw_tracepoint.name = ptr_to_u64(name); attr.raw_tracepoint.prog_fd = prog_fd; + attr.raw_tracepoint.tgt_prog_fd = OPTS_GET(opts, tgt_prog_fd, 0); + attr.raw_tracepoint.tgt_btf_id = OPTS_GET(opts, tgt_btf_id, 0); return sys_bpf(BPF_RAW_TRACEPOINT_OPEN, &attr, sizeof(attr)); } +int bpf_raw_tracepoint_open(const char *name, int prog_fd) +{ + return bpf_raw_tracepoint_open_opts(name, prog_fd, NULL); +} + int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size, bool do_log) { diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 015d13f25fcc..30e8854374c0 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -233,7 +233,16 @@ LIBBPF_API int bpf_obj_get_info_by_fd(int bpf_fd, void *info, __u32 *info_len); LIBBPF_API int bpf_prog_query(int target_fd, enum bpf_attach_type type, __u32 query_flags, __u32 *attach_flags, __u32 *prog_ids, __u32 *prog_cnt); +struct bpf_raw_tracepoint_opts { + size_t sz; /* size of this struct for forward/backward compatibility */ + int tgt_prog_fd; /* target program to attach to */ + __u32 tgt_btf_id; /* BTF ID of target function */ +}; +#define bpf_raw_tracepoint_opts__last_field tgt_btf_id + LIBBPF_API int bpf_raw_tracepoint_open(const char *name, int prog_fd); +LIBBPF_API int bpf_raw_tracepoint_open_opts(const char *name, int prog_fd, + struct bpf_raw_tracepoint_opts *opts); LIBBPF_API int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf, __u32 log_buf_size, bool do_log); LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf, diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 92ceb48a5ca2..a23d9f3f940c 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -303,6 +303,7 @@ LIBBPF_0.1.0 { LIBBPF_0.2.0 { global: bpf_program__section_name; + bpf_raw_tracepoint_open_opts; perf_buffer__buffer_cnt; perf_buffer__buffer_fd; perf_buffer__epoll_fd;