From patchwork Tue Jun 4 20:02:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 13685841 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DC45A146D78; Tue, 4 Jun 2024 20:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717531407; cv=none; b=XQG8YT2IdSsPg6iow458VgNZIhp9PrDd4kqA+IJZ2Y8HJORGqOdM8gLK5s5kxlO4qG7adaSNJ0iEvyDeFuvgMZSVmwg+Ysf+ZF2XHFUGZYQRWplbPg+IIbKzhqQFCZmKGiTlHokIYVzEGrFDZuYV3/zCkGiASeIdApWMBCMpGW0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717531407; c=relaxed/simple; bh=DggXebc+5AYH4oM8/iWPJWB6VFy1ERgOM6IPvJ6rIjs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GdapsL4AjmEWo/TDMK5A4lliHBFjtvhG/d0tp0zMl0HlmQWrzuwHYB/xskIklrNQazwQIexhzvuIt89JU1xkZZ4ARFXK2TQf2C5N5j1nF9rRPbd5EElaf5r2pIH468ZWK0eugQoXaJaJojajPYN501kihdioqmdPPG/KU6hPvIE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ILEvU0gT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ILEvU0gT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D32F7C2BBFC; Tue, 4 Jun 2024 20:03:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717531406; bh=DggXebc+5AYH4oM8/iWPJWB6VFy1ERgOM6IPvJ6rIjs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ILEvU0gTFvCYyzXJcUBLPA4oft6W+BmxISq3P/cmEVVan/6LPmsmuTLbkAhJbgWQn gIAeCrHBeykLM1cNbVWZcK6qKgTNNnWyCpcRTkYuPTRED6Ne6vcG0Zv1ao/BqxcG/2 E1eT/T6CMjmllRxsluhBxZr/DlnGkIiWqYUGMe7WwGO0gRlbuzGduycAPxnhXvZmsG Q6YyReZzxwZuMK+gGS9ZV26ycoQtJmQQp8m6VDqVRSVAbyUCGWcJOlv3WViGAymALC ALMHNn+nkghG0wl/CozwcDe3HDiPtGjvwTHHmCvqVgbyfN8h4Il36CGDp8PumztyMJ Jh5YUsNhjUKoA== From: Jiri Olsa To: Oleg Nesterov , Peter Zijlstra , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: bpf@vger.kernel.org, Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Steven Rostedt , Masami Hiramatsu , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [RFC bpf-next 04/10] libbpf: Add support for uprobe multi session attach Date: Tue, 4 Jun 2024 22:02:15 +0200 Message-ID: <20240604200221.377848-5-jolsa@kernel.org> X-Mailer: git-send-email 2.45.1 In-Reply-To: <20240604200221.377848-1-jolsa@kernel.org> References: <20240604200221.377848-1-jolsa@kernel.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Adding support to attach program in uprobe session mode with bpf_program__attach_uprobe_multi function. Adding session bool to bpf_uprobe_multi_opts struct that allows to load and attach the bpf program via uprobe session. the attachment to create uprobe multi session. Also adding new program loader section that allows: SEC("uprobe.session/bpf_fentry_test*") and loads/attaches uprobe program as uprobe session. Signed-off-by: Jiri Olsa --- tools/lib/bpf/bpf.c | 1 + tools/lib/bpf/libbpf.c | 50 ++++++++++++++++++++++++++++++++++++++++-- tools/lib/bpf/libbpf.h | 4 +++- 3 files changed, 52 insertions(+), 3 deletions(-) diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c index 2a4c71501a17..becdfa701c75 100644 --- a/tools/lib/bpf/bpf.c +++ b/tools/lib/bpf/bpf.c @@ -776,6 +776,7 @@ int bpf_link_create(int prog_fd, int target_fd, return libbpf_err(-EINVAL); break; case BPF_TRACE_UPROBE_MULTI: + case BPF_TRACE_UPROBE_SESSION: attr.link_create.uprobe_multi.flags = OPTS_GET(opts, uprobe_multi.flags, 0); attr.link_create.uprobe_multi.cnt = OPTS_GET(opts, uprobe_multi.cnt, 0); attr.link_create.uprobe_multi.path = ptr_to_u64(OPTS_GET(opts, uprobe_multi.path, 0)); diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index d1627a2ca30b..a0044448a708 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -9328,6 +9328,7 @@ static int attach_trace(const struct bpf_program *prog, long cookie, struct bpf_ static int attach_kprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_kprobe_session(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link); +static int attach_uprobe_session(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link); static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link); @@ -9346,6 +9347,7 @@ static const struct bpf_sec_def section_defs[] = { SEC_DEF("kprobe.session+", KPROBE, BPF_TRACE_KPROBE_SESSION, SEC_NONE, attach_kprobe_session), SEC_DEF("uprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), SEC_DEF("uretprobe.multi+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_NONE, attach_uprobe_multi), + SEC_DEF("uprobe.session+", KPROBE, BPF_TRACE_UPROBE_SESSION, SEC_NONE, attach_uprobe_session), SEC_DEF("uprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), SEC_DEF("uretprobe.multi.s+", KPROBE, BPF_TRACE_UPROBE_MULTI, SEC_SLEEPABLE, attach_uprobe_multi), SEC_DEF("ksyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall), @@ -11682,6 +11684,40 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru return ret; } +static int attach_uprobe_session(const struct bpf_program *prog, long cookie, struct bpf_link **link) +{ + char *binary_path = NULL, *func_name = NULL; + LIBBPF_OPTS(bpf_uprobe_multi_opts, opts, + .session = true, + ); + int n, ret = -EINVAL; + const char *spec; + + *link = NULL; + + spec = prog->sec_name + sizeof("uprobe.session/") - 1; + n = sscanf(spec, "%m[^:]:%m[^\n]", + &binary_path, &func_name); + + switch (n) { + case 1: + /* but auto-attach is impossible. */ + ret = 0; + break; + case 2: + *link = bpf_program__attach_uprobe_multi(prog, -1, binary_path, func_name, &opts); + ret = *link ? 0 : -errno; + break; + default: + pr_warn("prog '%s': invalid format of section definition '%s'\n", prog->name, + prog->sec_name); + break; + } + free(binary_path); + free(func_name); + return ret; +} + static void gen_uprobe_legacy_event_name(char *buf, size_t buf_sz, const char *binary_path, uint64_t offset) { @@ -11916,10 +11952,12 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, const unsigned long *ref_ctr_offsets = NULL, *offsets = NULL; LIBBPF_OPTS(bpf_link_create_opts, lopts); unsigned long *resolved_offsets = NULL; + enum bpf_attach_type attach_type; int err = 0, link_fd, prog_fd; struct bpf_link *link = NULL; char errmsg[STRERR_BUFSIZE]; char full_path[PATH_MAX]; + bool retprobe, session; const __u64 *cookies; const char **syms; size_t cnt; @@ -11990,12 +12028,20 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, offsets = resolved_offsets; } + retprobe = OPTS_GET(opts, retprobe, false); + session = OPTS_GET(opts, session, false); + + if (retprobe && session) + return libbpf_err_ptr(-EINVAL); + + attach_type = session ? BPF_TRACE_UPROBE_SESSION : BPF_TRACE_UPROBE_MULTI; + lopts.uprobe_multi.path = path; lopts.uprobe_multi.offsets = offsets; lopts.uprobe_multi.ref_ctr_offsets = ref_ctr_offsets; lopts.uprobe_multi.cookies = cookies; lopts.uprobe_multi.cnt = cnt; - lopts.uprobe_multi.flags = OPTS_GET(opts, retprobe, false) ? BPF_F_UPROBE_MULTI_RETURN : 0; + lopts.uprobe_multi.flags = retprobe ? BPF_F_UPROBE_MULTI_RETURN : 0; if (pid == 0) pid = getpid(); @@ -12009,7 +12055,7 @@ bpf_program__attach_uprobe_multi(const struct bpf_program *prog, } link->detach = &bpf_link__detach_fd; - link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_UPROBE_MULTI, &lopts); + link_fd = bpf_link_create(prog_fd, 0, attach_type, &lopts); if (link_fd < 0) { err = -errno; pr_warn("prog '%s': failed to attach multi-uprobe: %s\n", diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 26e4e35528c5..04cdb38f527f 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -569,10 +569,12 @@ struct bpf_uprobe_multi_opts { size_t cnt; /* create return uprobes */ bool retprobe; + /* create session kprobes */ + bool session; size_t :0; }; -#define bpf_uprobe_multi_opts__last_field retprobe +#define bpf_uprobe_multi_opts__last_field session /** * @brief **bpf_program__attach_uprobe_multi()** attaches a BPF program