From dafe58fc1917a96c657a0f56a12f262e5d9fb324 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Tue, 25 Aug 2020 21:21:16 +0200 Subject: [PATCH] bpf: Remove recursion call in btf_struct_access Andrii suggested we can simply jump to again label instead of making recursion call. Suggested-by: Andrii Nakryiko Signed-off-by: Jiri Olsa Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200825192124.710397-7-jolsa@kernel.org --- kernel/bpf/btf.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index ee0e2a5e6c88..4488c5b03941 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3931,14 +3931,13 @@ again: /* Only allow structure for now, can be relaxed for * other types later. */ - elem_type = btf_type_skip_modifiers(btf_vmlinux, - array_elem->type, NULL); - if (!btf_type_is_struct(elem_type)) + t = btf_type_skip_modifiers(btf_vmlinux, array_elem->type, + NULL); + if (!btf_type_is_struct(t)) goto error; - off = (off - moff) % elem_type->size; - return btf_struct_access(log, elem_type, off, size, atype, - next_btf_id); + off = (off - moff) % t->size; + goto again; error: bpf_log(log, "access beyond struct %s at off %u size %u\n",