From d4dfc5700e867b22ab94f960f9a9972696a637d5 Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko Date: Tue, 19 Mar 2024 16:38:49 -0700 Subject: bpf: pass whole link instead of prog when triggering raw tracepoint Instead of passing prog as an argument to bpf_trace_runX() helpers, that are called from tracepoint triggering calls, store BPF link itself (struct bpf_raw_tp_link for raw tracepoints). This will allow to pass extra information like BPF cookie into raw tracepoint registration. Instead of replacing `struct bpf_prog *prog = __data;` with corresponding `struct bpf_raw_tp_link *link = __data;` assignment in `__bpf_trace_##call` I just passed `__data` through into underlying bpf_trace_runX() call. This works well because we implicitly cast `void *`, and it also avoids naming clashes with arguments coming from tracepoint's "proto" list. We could have run into the same problem with "prog", we just happened to not have a tracepoint that has "prog" input argument. We are less lucky with "link", as there are tracepoints using "link" argument name already. So instead of trying to avoid naming conflicts, let's just remove intermediate local variable. It doesn't hurt readibility, it's either way a bit of a maze of calls and macros, that requires careful reading. Acked-by: Stanislav Fomichev Signed-off-by: Andrii Nakryiko Message-ID: <20240319233852.1977493-3-andrii@kernel.org> Signed-off-by: Alexei Starovoitov --- include/trace/bpf_probe.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/trace') diff --git a/include/trace/bpf_probe.h b/include/trace/bpf_probe.h index e609cd7da47e..a2ea11cc912e 100644 --- a/include/trace/bpf_probe.h +++ b/include/trace/bpf_probe.h @@ -46,8 +46,7 @@ static notrace void \ __bpf_trace_##call(void *__data, proto) \ { \ - struct bpf_prog *prog = __data; \ - CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(prog, CAST_TO_U64(args)); \ + CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(__data, CAST_TO_U64(args)); \ } #undef DECLARE_EVENT_CLASS -- cgit v1.2.3