From patchwork Thu Nov 18 11:24:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 12626695 X-Patchwork-Delegate: bpf@iogearbox.net 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E55AAC433F5 for ; Thu, 18 Nov 2021 11:29:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CDA3061246 for ; Thu, 18 Nov 2021 11:29:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344034AbhKRLcO (ORCPT ); Thu, 18 Nov 2021 06:32:14 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:57435 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343894AbhKRLaL (ORCPT ); Thu, 18 Nov 2021 06:30:11 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1637234831; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=bifxS4z5leMtv9W8fU/+OTbvzsJd1lcEkpE8E9OLG6I=; b=OAIZf4x/yaPDg+mMZgRWjAtxv/ADg5YGlbjOrUiieGZRayzMMyCvkOC6JJR9Gfm09mbkJj /3Gq5HRMy7gGFivX/Ou1pIDqGNFYFb/H8e7YtgImzP2MdxHd4NtfoeN7hqDbvmYI/rWjpl 4IWfFN8itOfEgJXDzxXNpeKD5myw3xc= Received: from mail-ed1-f70.google.com (mail-ed1-f70.google.com [209.85.208.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-536-hpS6kK2JPXaPk37fC68Tfw-1; Thu, 18 Nov 2021 06:27:10 -0500 X-MC-Unique: hpS6kK2JPXaPk37fC68Tfw-1 Received: by mail-ed1-f70.google.com with SMTP id m8-20020a056402510800b003e29de5badbso4965072edd.18 for ; Thu, 18 Nov 2021 03:27:10 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=bifxS4z5leMtv9W8fU/+OTbvzsJd1lcEkpE8E9OLG6I=; b=HoFtOwGQZPB/Wy8WJ2zUFMFTifLKb3JwOdPFs0tQE6rxxYqvnObfxSfJdxU8fQKfeW 1QmR6+WhwYdNXJeGaAafL0fdy2IVxveV88NneQPaf5alQ64VxRr66+VQWYEpKEr6wdux BrseuJODrkjhatCVXagkdpAQ8kzo+AlYB5bfEYd8LrxxFLG4UwPpkApCBy8jMTRhz371 CS0N5sSe2zEWTyXfzS0obAQDlOO+VknKuARyRh3G7Cjls0bZPFu5QSZ3sjT+MONiBDV4 AcpX+dlLT3N2HG5ZsIc1/ZfAsjjzmi39AGdAXUCYYgWEgkEWM6XOT15BTDr2iOmTOgTP LHDQ== X-Gm-Message-State: AOAM532j45GigTTq+uMFTLgHtuvV/GWoDfvbvMbZrRGpMx+V/YznFuxO Rmz0ueXV36uJoaMPfpNYl6ONwZvgc3O+kp9VmcwgQBOK7YrmIHH6338Lbz0O5oJ09ls/OV9l5wL 92NRk7JaFG0c4VvqW X-Received: by 2002:a17:907:972a:: with SMTP id jg42mr33022580ejc.398.1637234829295; Thu, 18 Nov 2021 03:27:09 -0800 (PST) X-Google-Smtp-Source: ABdhPJzXNac21cC6ptXLwE8vb976WG6H1rW4zE4vFEKA+xATsZW9m+DG21K1kz5v58zfN/C4PnINUw== X-Received: by 2002:a17:907:972a:: with SMTP id jg42mr33022545ejc.398.1637234829081; Thu, 18 Nov 2021 03:27:09 -0800 (PST) Received: from krava.redhat.com (nat-pool-brq-u.redhat.com. [213.175.37.12]) by smtp.gmail.com with ESMTPSA id bd12sm1464972edb.11.2021.11.18.03.27.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Nov 2021 03:27:08 -0800 (PST) From: Jiri Olsa X-Google-Original-From: Jiri Olsa To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh Subject: [PATCH bpf-next 22/29] libbpf: Add support to link multi func tracing program Date: Thu, 18 Nov 2021 12:24:48 +0100 Message-Id: <20211118112455.475349-23-jolsa@kernel.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211118112455.475349-1-jolsa@kernel.org> References: <20211118112455.475349-1-jolsa@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Adding support to link multi func tracing program through link_create interface. Adding special types for multi func programs: fentry.multi fexit.multi so you can define multi func programs like: SEC("fentry.multi/bpf_fentry_test*") int BPF_PROG(test1, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f) that defines test1 to be attached to bpf_fentry_test* functions. The test1 program is loaded with BPF_F_MULTI_FUNC flag. If functions are not specified the program needs to be attached manually. Adding new btf_ids/btf_ids_cnt fields to bpf_link_create_opts, that define functions to attach the program to. Signed-off-by: Jiri Olsa --- tools/lib/bpf/bpf.c | 7 +++++ tools/lib/bpf/bpf.h | 6 +++- tools/lib/bpf/libbpf.c | 66 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 78 insertions(+), 1 deletion(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 94560ba31724..86a95419e501 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -784,6 +784,13 @@ int bpf_link_create(int prog_fd, int target_fd, if (!OPTS_ZEROED(opts, perf_event)) return libbpf_err(-EINVAL); break; + case BPF_TRACE_FENTRY: + case BPF_TRACE_FEXIT: + attr.link_create.multi.btf_ids = (__u64) OPTS_GET(opts, multi.btf_ids, 0); + attr.link_create.multi.btf_ids_cnt = OPTS_GET(opts, multi.btf_ids_cnt, 0); + if (!OPTS_ZEROED(opts, multi)) + return libbpf_err(-EINVAL); + break; default: if (!OPTS_ZEROED(opts, flags)) return libbpf_err(-EINVAL); diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h index 079cc81ac51e..e55abf3528b3 100644 --- a/tools/lib/bpf/bpf.h +++ b/tools/lib/bpf/bpf.h @@ -249,10 +249,14 @@ struct bpf_link_create_opts { struct { __u64 bpf_cookie; } perf_event; + struct { + __u32 *btf_ids; + __u32 btf_ids_cnt; + } multi; }; size_t :0; }; -#define bpf_link_create_opts__last_field perf_event +#define bpf_link_create_opts__last_field multi LIBBPF_API int bpf_link_create(int prog_fd, int target_fd, enum bpf_attach_type attach_type, diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index de7e09a6b5ec..4c11d38b1f92 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -246,6 +246,8 @@ enum sec_def_flags { SEC_SLEEPABLE = 8, /* allow non-strict prefix matching */ SEC_SLOPPY_PFX = 16, + /* BPF program type allows multiple functions attachment */ + SEC_MULTI_FUNC = 32, }; struct bpf_sec_def { @@ -6723,6 +6725,9 @@ static int bpf_object_init_progs(struct bpf_object *obj, const struct bpf_object continue; } + if (prog->sec_def->cookie & SEC_MULTI_FUNC) + prog->prog_flags |= BPF_F_MULTI_FUNC; + bpf_program__set_type(prog, prog->sec_def->prog_type); bpf_program__set_expected_attach_type(prog, prog->sec_def->expected_attach_type); @@ -8318,6 +8323,7 @@ static struct bpf_link *attach_kprobe(const struct bpf_program *prog, long cooki static struct bpf_link *attach_tp(const struct bpf_program *prog, long cookie); static struct bpf_link *attach_raw_tp(const struct bpf_program *prog, long cookie); static struct bpf_link *attach_trace(const struct bpf_program *prog, long cookie); +static struct bpf_link *attach_trace_multi(const struct bpf_program *prog, long cookie); static struct bpf_link *attach_lsm(const struct bpf_program *prog, long cookie); static struct bpf_link *attach_iter(const struct bpf_program *prog, long cookie); @@ -8345,6 +8351,8 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("fentry.s/", TRACING, BPF_TRACE_FENTRY, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), SEC_DEF("fmod_ret.s/", TRACING, BPF_MODIFY_RETURN, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), SEC_DEF("fexit.s/", TRACING, BPF_TRACE_FEXIT, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace), + SEC_DEF("fentry.multi/", TRACING, BPF_TRACE_FENTRY, SEC_MULTI_FUNC, attach_trace_multi), + SEC_DEF("fexit.multi/", TRACING, BPF_TRACE_FEXIT, SEC_MULTI_FUNC, attach_trace_multi), SEC_DEF("freplace/", EXT, 0, SEC_ATTACH_BTF, attach_trace), SEC_DEF("lsm/", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF, attach_lsm), SEC_DEF("lsm.s/", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_lsm), @@ -8797,6 +8805,9 @@ static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attac __u32 attach_prog_fd = prog->attach_prog_fd; int err = 0; + if (prog->prog_flags & BPF_F_MULTI_FUNC) + return 0; + /* BPF program's BTF ID */ if (attach_prog_fd) { err = libbpf_find_prog_btf_id(attach_name, attach_prog_fd); @@ -10216,6 +10227,61 @@ static struct bpf_link *bpf_program__attach_btf_id(const struct bpf_program *pro return (struct bpf_link *)link; } +static struct bpf_link *bpf_program__attach_multi(const struct bpf_program *prog) +{ + char *pattern = prog->sec_name + strlen(prog->sec_def->sec); + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts); + enum bpf_attach_type attach_type; + int prog_fd, link_fd, cnt, err; + struct bpf_link *link = NULL; + __u32 *ids = NULL; + + prog_fd = bpf_program__fd(prog); + if (prog_fd < 0) { + pr_warn("prog '%s': can't attach before loaded\n", prog->name); + return ERR_PTR(-EINVAL); + } + + err = bpf_object__load_vmlinux_btf(prog->obj, true); + if (err) + return ERR_PTR(err); + + cnt = btf__find_by_glob_kind(prog->obj->btf_vmlinux, BTF_KIND_FUNC, + pattern, NULL, &ids); + if (cnt <= 0) + return ERR_PTR(-EINVAL); + + link = calloc(1, sizeof(*link)); + if (!link) { + err = -ENOMEM; + goto out_err; + } + link->detach = &bpf_link__detach_fd; + + opts.multi.btf_ids = ids; + opts.multi.btf_ids_cnt = cnt; + + attach_type = bpf_program__get_expected_attach_type(prog); + link_fd = bpf_link_create(prog_fd, 0, attach_type, &opts); + if (link_fd < 0) { + err = -errno; + goto out_err; + } + link->fd = link_fd; + free(ids); + return link; + +out_err: + free(link); + free(ids); + return ERR_PTR(err); +} + +static struct bpf_link *attach_trace_multi(const struct bpf_program *prog, long cookie) +{ + return bpf_program__attach_multi(prog); +} + struct bpf_link *bpf_program__attach_trace(const struct bpf_program *prog) { return bpf_program__attach_btf_id(prog);