From patchwork Fri Jun 21 04:55:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 1119948 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=fb.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=fb.com header.i=@fb.com header.b="Ex8UpC49"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45VRGg2VJSz9sBp for ; Fri, 21 Jun 2019 14:56:11 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725989AbfFUE4J (ORCPT ); Fri, 21 Jun 2019 00:56:09 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:11944 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725856AbfFUE4I (ORCPT ); Fri, 21 Jun 2019 00:56:08 -0400 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.27/8.16.0.27) with SMTP id x5L4q0k7003099 for ; Thu, 20 Jun 2019 21:56:06 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=facebook; bh=Y1FWKdBI5j0avkYfXEmpyA8NTajFIFgoZI9ySoULmg8=; b=Ex8UpC49jY/aIqd1AhgHJ4rjhGswed/kooZQxBwsS9vkskctNXVvylOzlVDhsXA3AdUB 63oS8qnsbVW+SpyMKbY9qmIbxoA2lKWhAxGdQ1RR/yCjISeSoUaa6I5JH0oVG/V86R/Z RFGhk1Ql5m94LtGOX+hRxHZ3TVouxLTHFG8= Received: from maileast.thefacebook.com ([163.114.130.16]) by m0001303.ppops.net with ESMTP id 2t7rtdea7h-4 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 20 Jun 2019 21:56:06 -0700 Received: from mx-out.facebook.com (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::f) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Thu, 20 Jun 2019 21:56:04 -0700 Received: by dev101.prn2.facebook.com (Postfix, from userid 137359) id 1D4DF861776; Thu, 20 Jun 2019 21:56:02 -0700 (PDT) Smtp-Origin-Hostprefix: dev From: Andrii Nakryiko Smtp-Origin-Hostname: dev101.prn2.facebook.com To: , , , , , , CC: Andrii Nakryiko Smtp-Origin-Cluster: prn2c23 Subject: [PATCH v2 bpf-next 2/7] libbpf: add ability to attach/detach BPF to perf event Date: Thu, 20 Jun 2019 21:55:50 -0700 Message-ID: <20190621045555.4152743-3-andriin@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190621045555.4152743-1-andriin@fb.com> References: <20190621045555.4152743-1-andriin@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-06-21_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906210041 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org bpf_program__attach_perf_event allows to attach BPF program to existing perf event, providing most generic and most low-level way to attach BPF programs. libbpf_perf_event_disable_and_close API is added to disable and close existing perf event by its FD. Signed-off-by: Andrii Nakryiko --- tools/lib/bpf/libbpf.c | 41 ++++++++++++++++++++++++++++++++++++++++ tools/lib/bpf/libbpf.h | 4 ++++ tools/lib/bpf/libbpf.map | 2 ++ 3 files changed, 47 insertions(+) diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 8ce3beba8551..2bb1fa008be3 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include #include @@ -3928,6 +3929,46 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, return 0; } +int libbpf_perf_event_disable_and_close(int pfd) +{ + int err; + + if (pfd < 0) + return 0; + + err = ioctl(pfd, PERF_EVENT_IOC_DISABLE, 0); + close(pfd); + return err; +} + +int bpf_program__attach_perf_event(struct bpf_program *prog, int pfd) +{ + char errmsg[STRERR_BUFSIZE]; + int bpf_fd, err; + + bpf_fd = bpf_program__fd(prog); + if (bpf_fd < 0) { + pr_warning("program '%s': can't attach before loaded\n", + bpf_program__title(prog, false)); + return -EINVAL; + } + if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, bpf_fd) < 0) { + err = -errno; + pr_warning("program '%s': failed to attach to pfd %d: %s\n", + bpf_program__title(prog, false), pfd, + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + return err; + } + if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { + err = -errno; + pr_warning("program '%s': failed to enable pfd %d: %s\n", + bpf_program__title(prog, false), pfd, + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); + return err; + } + return 0; +} + enum bpf_perf_event_ret bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, void **copy_mem, size_t *copy_size, diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index d639f47e3110..76db1bbc0dac 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -165,6 +165,10 @@ LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path); LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path); LIBBPF_API void bpf_program__unload(struct bpf_program *prog); +LIBBPF_API int libbpf_perf_event_disable_and_close(int pfd); +LIBBPF_API int bpf_program__attach_perf_event(struct bpf_program *prog, + int pfd); + struct bpf_insn; /* diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index 2c6d835620d2..d27406982b5a 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -172,5 +172,7 @@ LIBBPF_0.0.4 { btf_dump__new; btf__parse_elf; bpf_object__load_xattr; + bpf_program__attach_perf_event; libbpf_num_possible_cpus; + libbpf_perf_event_disable_and_close; } LIBBPF_0.0.3;