From nobody Sat Apr 11 02:17:20 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 67CDFC25B0E for ; Tue, 16 Aug 2022 21:50:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237736AbiHPVuD (ORCPT ); Tue, 16 Aug 2022 17:50:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35994 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237728AbiHPVtx (ORCPT ); Tue, 16 Aug 2022 17:49:53 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1854C6BCF4 for ; Tue, 16 Aug 2022 14:49:51 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id w124-20020a627b82000000b0052d8ebfc055so4235124pfc.19 for ; Tue, 16 Aug 2022 14:49:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:from:to:cc; bh=+IZonXkzDm1dEfVfdUlFehFeeEEGH9j0xN4V/zmAjFg=; b=hUfqzQwnfCoU3faaWeSpDvoPKyMwGRIv0zbWcQPBPXQ24yDBBkjm74Nz0VOOeLO+CW DQnhLkbbHAqAuPNnZ8ZtbPh035HjSDPyEi5noEEgV7u+tcLGcwURxBgJg7VqqUSRHlmR HAWZVgAq82DZvdMQp2ce627ee8ArThgBWJsad6S3suURK4sQI/WB4tazSFyvcNr0yWYl 0Qr4rDYjMSir8BzoDnEv7qp82Oz7wGw3PA6zI5ZLen7qS/rR2nT8VZ3vOA9cuAVMWTgT 1P38iZhZa4EAYba+VYn87vYfl6Fq7bPNTzwcMhM9+yMhwrOuwHcRbIrtlzPIsHCJUWOA cVfQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:mime-version:message-id:date:x-gm-message-state :from:to:cc; bh=+IZonXkzDm1dEfVfdUlFehFeeEEGH9j0xN4V/zmAjFg=; b=rdw5B+RlikMrJgCiro4ROUNp5BD0y5uFhvw03vpaQp1IbJdvTSLLPI+JYXLl/hD8ix l7y988h5kbIfwPm/AChhSElXvnWkprmYdz2Bd/3+iCo40IuWcONExSYLtRIifFRu6vjQ RBuGzv4j6Xo26k40999WJ6yniCbJ2/IIt9UsnZkKjtElRuCM2b4LvtYBORngXo0V/m9+ ulpoPkvx0HIj13Gz6dgCqkzZw4intK5eod4GHLUwMetCmVUNkTaTqfLposIxjLC/QejX MCqWT4pWPt285VZ2giVmErGnVHy8AU1ilIkPeLgHKaA1FOeY4cDtMeR9pvBXI2M82AU1 Hepw== X-Gm-Message-State: ACgBeo0UyKHH/VzLKbZcWHDnota39ISPqEFbPxqUz+4S7AGKvngR2RQH 0peNiRfPjtS0q+ynAm7EFgtSBcXmOi4Eth9zNLDyv82eS0xLuthkQvDIOJGm6puh42Iw7PwFJV6 +VjdIoAGdv52ILuL37ombA4CLL1D7L0K/ihg8sLtm+zLFoWCJ3/mrCAwKwDw1QQ+g8a2i1A== X-Google-Smtp-Source: AA6agR7XFdifIKPgmL8Q6duKo79x0wbP/flH2ziJSlt3d5V2GIzO+qdqLZLi2pBy8ZVqMFQxqftWFICxFMk= X-Received: from haoluo.svl.corp.google.com ([2620:15c:2d4:203:7e6e:c287:3dc6:d4d8]) (user=haoluo job=sendgmr) by 2002:a17:902:ef96:b0:170:d01d:df13 with SMTP id iz22-20020a170902ef9600b00170d01ddf13mr23999754plb.53.1660686590091; Tue, 16 Aug 2022 14:49:50 -0700 (PDT) Date: Tue, 16 Aug 2022 14:49:45 -0700 Message-Id: <20220816214945.742924-1-haoluo@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.595.g718a3a8f04-goog Subject: [PATCH bpf-next] libbpf: allow disabling auto attach From: Hao Luo To: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, netdev@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , KP Singh , John Fastabend , Stanislav Fomichev , Yosry Ahmed , Jiri Olsa , Hao Luo Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Add libbpf APIs for disabling auto-attach for individual functions. This is motivated by the use case of cgroup iter [1]. Some iter types require their parameters to be non-zero, therefore applying auto-attach on them will fail. With these two new APIs, Users who want to use auto-attach and these types of iters can disable auto-attach for them and perform manual attach. [1] https://lore.kernel.org/bpf/CAEf4BzZ+a2uDo_t6kGBziqdz--m2gh2_EUwkGLDtMd= 65uwxUjA@mail.gmail.com/ Signed-off-by: Hao Luo --- tools/lib/bpf/libbpf.c | 16 ++++++++++++++++ tools/lib/bpf/libbpf.h | 2 ++ 2 files changed, 18 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index aa05a99b913d..25f654d25b46 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -417,6 +417,7 @@ struct bpf_program { =20 int fd; bool autoload; + bool autoattach; bool mark_btf_static; enum bpf_prog_type type; enum bpf_attach_type expected_attach_type; @@ -755,6 +756,8 @@ bpf_object__init_prog(struct bpf_object *obj, struct bp= f_program *prog, prog->autoload =3D true; } =20 + prog->autoattach =3D true; + /* inherit object's log_level */ prog->log_level =3D obj->log_level; =20 @@ -8314,6 +8317,16 @@ int bpf_program__set_autoload(struct bpf_program *pr= og, bool autoload) return 0; } =20 +bool bpf_program__autoattach(const struct bpf_program *prog) +{ + return prog->autoattach; +} + +void bpf_program__set_autoattach(struct bpf_program *prog, bool autoattach) +{ + prog->autoattach =3D autoattach; +} + const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog) { return prog->insns; @@ -12349,6 +12362,9 @@ int bpf_object__attach_skeleton(struct bpf_object_s= keleton *s) if (!prog->autoload) continue; =20 + if (!prog->autoattach) + continue; + /* auto-attaching not supported for this program */ if (!prog->sec_def || !prog->sec_def->prog_attach_fn) continue; diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 61493c4cddac..88a1ac34b12a 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -260,6 +260,8 @@ LIBBPF_API const char *bpf_program__name(const struct b= pf_program *prog); LIBBPF_API const char *bpf_program__section_name(const struct bpf_program = *prog); LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog); LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool au= toload); +LIBBPF_API bool bpf_program__autoattach(const struct bpf_program *prog); +LIBBPF_API void bpf_program__set_autoattach(struct bpf_program *prog, bool= autoattach); =20 struct bpf_insn; =20 --=20 2.37.1.595.g718a3a8f04-goog