diff options
| author | Donglin Peng <pengdonglin@xiaomi.com> | 2026-01-09 21:00:00 +0800 |
|---|---|---|
| committer | Andrii Nakryiko <andrii@kernel.org> | 2026-01-13 16:21:36 -0800 |
| commit | dc893cfa390aa9d5fc83c908ea5e37a36e531892 (patch) | |
| tree | 8519155a3a06fa6d406c2475e0970c6fb0def5bb /kernel/bpf | |
| parent | 342bf525ba0d83374f318e19186d50b1e7160d0e (diff) | |
bpf: Skip anonymous types in type lookup for performance
Currently, vmlinux and kernel module BTFs are unconditionally
sorted during the build phase, with named types placed at the
end. Thus, anonymous types should be skipped when starting the
search. In my vmlinux BTF, the number of anonymous types is
61,747, which means the loop count can be reduced by 61,747.
Signed-off-by: Donglin Peng <pengdonglin@xiaomi.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260109130003.3313716-9-dolinux.peng@gmail.com
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/btf.c | 10 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 7 |
2 files changed, 7 insertions, 10 deletions
diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index d5b3a37c8560..364dd84bfc5a 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3534,7 +3534,8 @@ const char *btf_find_decl_tag_value(const struct btf *btf, const struct btf_type const struct btf_type *t; int len, id; - id = btf_find_next_decl_tag(btf, pt, comp_idx, tag_key, 0); + id = btf_find_next_decl_tag(btf, pt, comp_idx, tag_key, + btf_named_start_id(btf, false) - 1); if (id < 0) return ERR_PTR(id); @@ -7844,12 +7845,13 @@ int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog) tname); return -EINVAL; } + /* Convert BTF function arguments into verifier types. * Only PTR_TO_CTX and SCALAR are supported atm. */ for (i = 0; i < nargs; i++) { u32 tags = 0; - int id = 0; + int id = btf_named_start_id(btf, false) - 1; /* 'arg:<tag>' decl_tag takes precedence over derivation of * register type from BTF type itself @@ -9338,7 +9340,7 @@ bpf_core_find_cands(struct bpf_core_ctx *ctx, u32 local_type_id) } /* Attempt to find target candidates in vmlinux BTF first */ - cands = bpf_core_add_cands(cands, main_btf, 1); + cands = bpf_core_add_cands(cands, main_btf, btf_named_start_id(main_btf, true)); if (IS_ERR(cands)) return ERR_CAST(cands); @@ -9370,7 +9372,7 @@ check_modules: */ btf_get(mod_btf); spin_unlock_bh(&btf_idr_lock); - cands = bpf_core_add_cands(cands, mod_btf, btf_nr_types(main_btf)); + cands = bpf_core_add_cands(cands, mod_btf, btf_named_start_id(mod_btf, true)); btf_put(mod_btf); if (IS_ERR(cands)) return ERR_CAST(cands); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 092003cc7841..45733bae271d 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -20687,12 +20687,7 @@ static int find_btf_percpu_datasec(struct btf *btf) * types to look at only module's own BTF types. */ n = btf_nr_types(btf); - if (btf_is_module(btf)) - i = btf_nr_types(btf_vmlinux); - else - i = 1; - - for(; i < n; i++) { + for (i = btf_named_start_id(btf, true); i < n; i++) { t = btf_type_by_id(btf, i); if (BTF_INFO_KIND(t->info) != BTF_KIND_DATASEC) continue; |