Adding support to use bpf_get_stack_kfunc in
BPF_TRACE_FENTRY/BPF_TRACE_FEXIT programs.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
kernel/trace/bpf_trace.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 18d6e96751c4..5c8edede3ac4 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1223,6 +1223,32 @@ static const struct bpf_func_proto bpf_get_stackid_proto_kfunc = {
.arg3_type = ARG_ANYTHING,
};
+BPF_CALL_4(bpf_get_stack_kfunc, void*, args,
+ void *, buf, u32, size, 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_stack((unsigned long) regs, (unsigned long) buf,
+ (unsigned long) size, flags, 0);
+ put_bpf_raw_tp_regs();
+ return ret;
+}
+
+static const struct bpf_func_proto bpf_get_stack_proto_kfunc = {
+ .func = bpf_get_stack_raw_tp,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_PTR_TO_MEM,
+ .arg3_type = ARG_CONST_SIZE_OR_ZERO,
+ .arg4_type = ARG_ANYTHING,
+};
+
static const struct bpf_func_proto *
kfunc_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
@@ -1231,6 +1257,8 @@ kfunc_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &bpf_perf_event_output_proto_kfunc;
case BPF_FUNC_get_stackid:
return &bpf_get_stackid_proto_kfunc;
+ case BPF_FUNC_get_stack:
+ return &bpf_get_stack_proto_kfunc;
default:
return tracing_func_proto(func_id, prog);
}
--
2.24.1
