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charset="utf-8" Automatically enabling a perf event after attaching a BPF prog to it is not always desirable. Add a new "dont_enable" field to struct bpf_perf_event_opts. While introducing "enable" instead would be nicer in that it would avoid a double negation in the implementation, it would make DECLARE_LIBBPF_OPTS() less efficient. Acked-by: Eduard Zingerman Suggested-by: Jiri Olsa Tested-by: Thomas Richter Co-developed-by: Thomas Richter Signed-off-by: Thomas Richter Signed-off-by: Ilya Leoshkevich --- tools/lib/bpf/libbpf.c | 13 ++++++++----- tools/lib/bpf/libbpf.h | 4 +++- 2 files changed, 11 insertions(+), 6 deletions(-) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index fb4d92c5c339..8f5a81b672e1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -10965,11 +10965,14 @@ struct bpf_link *bpf_program__attach_perf_event_o= pts(const struct bpf_program *p } link->link.fd =3D pfd; } - if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { - err =3D -errno; - pr_warn("prog '%s': failed to enable perf_event FD %d: %s\n", - prog->name, pfd, errstr(err)); - goto err_out; + + if (!OPTS_GET(opts, dont_enable, false)) { + if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { + err =3D -errno; + pr_warn("prog '%s': failed to enable perf_event FD %d: %s\n", + prog->name, pfd, errstr(err)); + goto err_out; + } } =20 return &link->link; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index d1cf813a057b..455a957cb702 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -499,9 +499,11 @@ struct bpf_perf_event_opts { __u64 bpf_cookie; /* don't use BPF link when attach BPF program */ bool force_ioctl_attach; + /* don't automatically enable the event */ + bool dont_enable; size_t :0; }; -#define bpf_perf_event_opts__last_field force_ioctl_attach +#define bpf_perf_event_opts__last_field dont_enable =20 LIBBPF_API struct bpf_link * bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd); --=20 2.50.1