This patch adds and side band event to capture bpf_prog_info and btf of short living bpf programs.
Signed-off-by: Song Liu <songliubrav...@fb.com> --- tools/perf/builtin-record.c | 3 ++ tools/perf/builtin-top.c | 3 ++ tools/perf/util/bpf-event.c | 66 +++++++++++++++++++++++++++++++++++++ tools/perf/util/bpf-event.h | 18 ++++++++++ tools/perf/util/evlist.c | 5 +++ 5 files changed, 95 insertions(+) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index d10c1d5a9e89..ce26d37c2871 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -1207,6 +1207,9 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) goto out_child; } + if (opts->bpf_event) + bpf_event__add_polling_event(); + poll_args.env = &session->header.env; poll_args.done = &done; perf_evlist__start_polling_thread(&rec->opts.target, &poll_args); diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index f41545445917..851c4dcce66f 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -1655,6 +1655,9 @@ int cmd_top(int argc, const char **argv) top.record_opts.bpf_event = !top.no_bpf_event; + if (top.record_opts.bpf_event) + bpf_event__add_polling_event(); + poll_args.env = &perf_env; poll_args.done = &done; perf_evlist__start_polling_thread(target, &poll_args); diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 048ef00371ad..664906237ffb 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -12,6 +12,7 @@ #include "machine.h" #include "env.h" #include "session.h" +#include "evlist.h" #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) @@ -332,3 +333,68 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, free(event); return err; } + +void perf_env__add_bpf_info(struct perf_env *env, u32 id) +{ + struct bpf_prog_info_linear *info_linear; + struct bpf_prog_info_node *info_node; + struct btf *btf = NULL; + u64 arrays; + u32 btf_id; + int fd; + + fd = bpf_prog_get_fd_by_id(id); + if (fd < 0) + return; + + arrays = 1UL << BPF_PROG_INFO_JITED_KSYMS; + arrays |= 1UL << BPF_PROG_INFO_JITED_FUNC_LENS; + arrays |= 1UL << BPF_PROG_INFO_FUNC_INFO; + arrays |= 1UL << BPF_PROG_INFO_PROG_TAGS; + arrays |= 1UL << BPF_PROG_INFO_JITED_INSNS; + arrays |= 1UL << BPF_PROG_INFO_LINE_INFO; + arrays |= 1UL << BPF_PROG_INFO_JITED_LINE_INFO; + + info_linear = bpf_program__get_prog_info_linear(fd, arrays); + if (IS_ERR_OR_NULL(info_linear)) { + pr_debug("%s: failed to get BPF program info. aborting\n", __func__); + goto out; + } + + btf_id = info_linear->info.btf_id; + + info_node = malloc(sizeof(struct bpf_prog_info_node)); + if (info_node) { + info_node->info_linear = info_linear; + perf_env__insert_bpf_prog_info(env, info_node); + } else + free(info_linear); + + if (btf_id == 0) + goto out; + + if (btf__get_from_id(btf_id, &btf)) { + pr_debug("%s: failed to get BTF of id %u, aborting\n", + __func__, btf_id); + goto out; + } + perf_env__fetch_btf(env, btf_id, btf); + +out: + free(btf); + close(fd); +} + +int bpf_event__add_polling_event(void) +{ + struct perf_event_attr attr = { + .type = PERF_TYPE_SOFTWARE, + .config = PERF_COUNT_SW_DUMMY, + .watermark = 1, + .bpf_event = 1, + .wakeup_watermark = 1, + .size = sizeof(attr), /* to capture ABI version */ + }; + + return perf_evlist__new_side_band_event(&attr); +} diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h index b9ec394dc7c7..03a6f018e219 100644 --- a/tools/perf/util/bpf-event.h +++ b/tools/perf/util/bpf-event.h @@ -4,12 +4,17 @@ #include <linux/compiler.h> #include <linux/rbtree.h> +#include <pthread.h> +#include <api/fd/array.h> #include "event.h" struct machine; union perf_event; +struct perf_env; struct perf_sample; struct record_opts; +struct evlist; +struct target; struct bpf_prog_info_node { struct bpf_prog_info_linear *info_linear; @@ -31,6 +36,9 @@ int perf_event__synthesize_bpf_events(struct perf_session *session, perf_event__handler_t process, struct machine *machine, struct record_opts *opts); +int bpf_event__add_polling_event(void); +void perf_env__add_bpf_info(struct perf_env *env, u32 id); + #else static inline int machine__process_bpf_event(struct machine *machine __maybe_unused, union perf_event *event __maybe_unused, @@ -46,5 +54,15 @@ static inline int perf_event__synthesize_bpf_events(struct perf_session *session { return 0; } + +static inline int bpf_event__add_polling_event(void) +{ + return 0; +} + +void perf_env__add_bpf_info(struct perf_env *env __maybe_unused, + u32 id __maybe_unused) +{ +} #endif // HAVE_LIBBPF_SUPPORT #endif diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 61b87c8111e6..58ac42878c0a 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1886,6 +1886,11 @@ static void *perf_evlist__poll_thread(void *arg) pr_debug("processing vip event of type %d\n", event->header.type); switch (event->header.type) { + case PERF_RECORD_BPF_EVENT: + if (event->bpf_event.type != PERF_BPF_EVENT_PROG_LOAD) + break; + perf_env__add_bpf_info(args->env, event->bpf_event.id); + break; default: break; } -- 2.17.1