diff options
author | Ilya Leoshkevich <iii@linux.ibm.com> | 2025-08-06 18:22:41 +0200 |
---|---|---|
committer | Alexei Starovoitov <ast@kernel.org> | 2025-08-07 09:01:41 -0700 |
commit | 9474e27a24a41e55d0ac2b77d8171fddec7dbb87 (patch) | |
tree | ebc01697c97408eaf8e24073cb5c1d913af08fe3 /tools/lib/bpf/libbpf.c | |
parent | 1b30d44417278196a90c79244bb43e8428586345 (diff) |
libbpf: Add the ability to suppress perf event enablement
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 <eddyz87@gmail.com>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Co-developed-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20250806162417.19666-2-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r-- | tools/lib/bpf/libbpf.c | 13 |
1 files changed, 8 insertions, 5 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_opts(const struct bpf_program *p } link->link.fd = pfd; } - if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { - err = -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 = -errno; + pr_warn("prog '%s': failed to enable perf_event FD %d: %s\n", + prog->name, pfd, errstr(err)); + goto err_out; + } } return &link->link; |