From: Donglin Peng This patch checks whether the BTF is sorted by name in ascending order. If sorted, binary search will be used when looking up types. Cc: Eduard Zingerman Cc: Alexei Starovoitov Cc: Andrii Nakryiko Cc: Alan Maguire Cc: Ihor Solodrai Cc: Xiaoqin Zhang Signed-off-by: Donglin Peng Acked-by: Eduard Zingerman --- tools/lib/bpf/btf.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c index 60ff8eafea83..277df0077df6 100644 --- a/tools/lib/bpf/btf.c +++ b/tools/lib/bpf/btf.c @@ -899,6 +899,30 @@ int btf__resolve_type(const struct btf *btf, __u32 type_id) return type_id; } +static void btf_check_sorted(struct btf *btf) +{ + __u32 i, n, named_start_id = 0; + + n = btf__type_cnt(btf); + for (i = btf->start_id + 1; i < n; i++) { + struct btf_type *ta = btf_type_by_id(btf, i - 1); + struct btf_type *tb = btf_type_by_id(btf, i); + const char *na = btf__str_by_offset(btf, ta->name_off); + const char *nb = btf__str_by_offset(btf, tb->name_off); + + if (strcmp(na, nb) > 0) + return; + + if (named_start_id == 0 && na[0] != '\0') + named_start_id = i - 1; + if (named_start_id == 0 && nb[0] != '\0') + named_start_id = i; + } + + if (named_start_id) + btf->named_start_id = named_start_id; +} + static __s32 btf_find_type_by_name_bsearch(const struct btf *btf, const char *name, __s32 start_id) { @@ -1132,6 +1156,7 @@ static struct btf *btf_new(const void *data, __u32 size, struct btf *base_btf, b err = err ?: btf_sanity_check(btf); if (err) goto done; + btf_check_sorted(btf); done: if (err) { -- 2.34.1