[PATCH 3/6] bpf: Add bpf_get_stackid_kfunc
From: Jiri Olsa <jolsa@kernel.org>
Date: 2020-01-21 12:05:30
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [security & lsm] (security audit and enforcement using bpf), bpf [tracing], the rest, tracing · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, KP Singh, Matt Bobrowski, Song Liu, Linus Torvalds, Steven Rostedt, Masami Hiramatsu
Adding support to use bpf_get_stackid_kfunc in BPF_TRACE_FENTRY/BPF_TRACE_FEXIT programs. Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- kernel/trace/bpf_trace.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 6a18e2ae6e30..18d6e96751c4 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c@@ -1198,12 +1198,39 @@ static const struct bpf_func_proto bpf_perf_event_output_proto_kfunc = { .arg5_type = ARG_CONST_SIZE_OR_ZERO, }; +BPF_CALL_3(bpf_get_stackid_kfunc, void*, args, + struct bpf_map *, map, u64, flags) +{ + struct pt_regs *regs = get_bpf_raw_tp_regs(); + int ret; + + if (IS_ERR(regs)) + return PTR_ERR(regs); + + perf_fetch_caller_regs(regs); + ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map, + flags, 0, 0); + put_bpf_raw_tp_regs(); + return ret; +} + +static const struct bpf_func_proto bpf_get_stackid_proto_kfunc = { + .func = bpf_get_stackid_kfunc, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, +}; + static const struct bpf_func_proto * kfunc_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) { switch (func_id) { case BPF_FUNC_perf_event_output: return &bpf_perf_event_output_proto_kfunc; + case BPF_FUNC_get_stackid: + return &bpf_get_stackid_proto_kfunc; default: return tracing_func_proto(func_id, prog); }
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2.24.1