Messages in this thread Patch in this message | | | From | Kyle Huey <> | Subject | [PATCH v2 2/3] perf/bpf: Allow a bpf program to suppress all sample side effects. | Date | Thu, 7 Dec 2023 08:34:57 -0800 |
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Returning zero from a bpf program attached to a perf event already suppresses any data output. By clearing pending_kill, returning zero from a bpf program will effectively pretend the sample never happened for all userspace purposes.
Signed-off-by: Kyle Huey <khuey@kylehuey.com> --- kernel/events/core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/events/core.c b/kernel/events/core.c index 19fddfc27a4a..6cda05a4969d 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10421,8 +10421,10 @@ static void bpf_overflow_handler(struct perf_event *event, rcu_read_unlock(); out: __this_cpu_dec(bpf_prog_active); - if (!ret) + if (!ret) { + event->pending_kill = 0; return; + } event->orig_overflow_handler(event, data, regs); } -- 2.34.1
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