From patchwork Tue Jan 15 18:53:47 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Liu X-Patchwork-Id: 1025370 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="Hq1mJeHI"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43fKJn6jgSz9sCr for ; Wed, 16 Jan 2019 05:54:49 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389102AbfAOSys (ORCPT ); Tue, 15 Jan 2019 13:54:48 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:38818 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388998AbfAOSyH (ORCPT ); Tue, 15 Jan 2019 13:54:07 -0500 Received: from pps.filterd (m0044012.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x0FIoVgx005077 for ; Tue, 15 Jan 2019 10:54:06 -0800 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=EdAqG1NomWGwJ6u5rAasObNyP1zBZi9ATk/m+RL16U0=; b=Hq1mJeHI6j0JGMI+TEnZG77EzAUfV2c4o/VOBfuPygY39td+nV12IzyhJU/JC2ZZ2s5s foEBBtZzyh3YNJtBX0x6uyyhf7gW+WLWKGO+P+hCM6b7Bz+31ELxuIiqDYySSwLUMCKb xwjlKL2EDxSMCVFfUf+MjkF7C8NfMF6VKTs= Received: from mail.thefacebook.com ([199.201.64.23]) by mx0a-00082601.pphosted.com with ESMTP id 2q1k4drh83-6 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT) for ; Tue, 15 Jan 2019 10:54:06 -0800 Received: from mx-out.facebook.com (2620:10d:c081:10::13) by mail.thefacebook.com (2620:10d:c081:35::130) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA) id 15.1.1531.3; Tue, 15 Jan 2019 10:53:54 -0800 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id C01F262E1068; Tue, 15 Jan 2019 10:53:51 -0800 (PST) Smtp-Origin-Hostprefix: devbig From: Song Liu Smtp-Origin-Hostname: devbig006.ftw2.facebook.com To: , CC: Song Liu , , , , , , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v8 perf, bpf-next 7/9] perf tools: synthesize PERF_RECORD_* for loaded BPF programs Date: Tue, 15 Jan 2019 10:53:47 -0800 Message-ID: <20190115185349.1191609-8-songliubraving@fb.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190115185349.1191609-1-songliubraving@fb.com> References: <20190115185349.1191609-1-songliubraving@fb.com> X-FB-Internal: Safe MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-01-15_06:, , signatures=0 X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This patch synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for BPF programs loaded before perf-record. This is achieved by gathering information about all BPF programs via sys_bpf. Signed-off-by: Song Liu --- tools/perf/builtin-record.c | 6 ++ tools/perf/util/bpf-event.c | 206 ++++++++++++++++++++++++++++++++++++ tools/perf/util/bpf-event.h | 5 + 3 files changed, 217 insertions(+) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index deaf9b902094..88ea11d57c6f 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -41,6 +41,7 @@ #include "util/perf-hooks.h" #include "util/time-utils.h" #include "util/units.h" +#include "util/bpf-event.h" #include "asm/bug.h" #include @@ -1082,6 +1083,11 @@ static int record__synthesize(struct record *rec, bool tail) return err; } + err = perf_event__synthesize_bpf_events(tool, process_synthesized_event, + machine, opts); + if (err < 0) + pr_warning("Couldn't synthesize bpf events.\n"); + err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->threads, process_synthesized_event, opts->sample_address, 1); diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 87004706874f..4fe30ad622b8 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -1,10 +1,24 @@ // SPDX-License-Identifier: GPL-2.0 #include #include +#include +#include #include "bpf-event.h" #include "debug.h" #include "symbol.h" +#define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) + +static int snprintf_hex(char *buf, size_t size, unsigned char *data, size_t len) +{ + int ret = 0; + size_t i; + + for (i = 0; i < len; i++) + ret += snprintf(buf + ret, size - ret, "%02x", data[i]); + return ret; +} + int machine__process_bpf_event(struct machine *machine __maybe_unused, union perf_event *event, struct perf_sample *sample __maybe_unused) @@ -13,3 +27,195 @@ int machine__process_bpf_event(struct machine *machine __maybe_unused, perf_event__fprintf_bpf_event(event, stdout); return 0; } + +/* + * Synthesize PERF_RECORD_KSYMBOL and PERF_RECORD_BPF_EVENT for one bpf + * program. One PERF_RECORD_BPF_EVENT is generated for the program. And + * one PERF_RECORD_KSYMBOL is generated for each sub program. + */ +static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool, + perf_event__handler_t process, + struct machine *machine, + int fd, + union perf_event *event, + struct record_opts *opts) +{ + struct ksymbol_event *ksymbol_event = &event->ksymbol_event; + struct bpf_event *bpf_event = &event->bpf_event; + u32 sub_prog_cnt, i, func_info_rec_size; + u8 (*prog_tags)[BPF_TAG_SIZE] = NULL; + struct bpf_prog_info info = {}; + u32 info_len = sizeof(info); + void *func_infos = NULL; + u64 *prog_addrs = NULL; + struct btf *btf = NULL; + u32 *prog_lens = NULL; + bool has_btf = false; + int err = 0; + + /* Call bpf_obj_get_info_by_fd() to get sizes of arrays */ + err = bpf_obj_get_info_by_fd(fd, &info, &info_len); + + if (err || info_len < 192 /* need field prog_tags */) + return -1; + + /* number of ksyms, func_lengths, and tags should match */ + sub_prog_cnt = info.nr_jited_ksyms; + if (sub_prog_cnt != info.nr_prog_tags || + sub_prog_cnt != info.nr_jited_func_lens) + return -1; + + /* check BTF func info support */ + if (info.btf_id && info.nr_func_info && info.func_info_rec_size) { + /* btf func info number should be same as sub_prog_cnt */ + if (sub_prog_cnt != info.nr_func_info) + return -1; + if (btf__get_from_id(info.btf_id, &btf)) + return -1; + func_info_rec_size = info.func_info_rec_size; + func_infos = malloc(sub_prog_cnt * func_info_rec_size); + if (!func_infos) + return -1; + has_btf = true; + } + + /* + * We need address, length, and tag for each sub program. + * Allocate memory and call bpf_obj_get_info_by_fd() again + */ + prog_addrs = (u64 *)malloc(sizeof(u64) * sub_prog_cnt); + prog_lens = (u32 *)malloc(sizeof(u64) * sub_prog_cnt); + prog_tags = malloc(sizeof(u8) * BPF_TAG_SIZE * sub_prog_cnt); + + err = !prog_addrs || !prog_lens || !prog_tags; + if (err) + goto out; + + memset(&info, 0, sizeof(info)); + info.nr_jited_ksyms = sub_prog_cnt; + info.nr_jited_func_lens = sub_prog_cnt; + info.nr_prog_tags = sub_prog_cnt; + info.jited_ksyms = ptr_to_u64(prog_addrs); + info.jited_func_lens = ptr_to_u64(prog_lens); + info.prog_tags = ptr_to_u64(prog_tags); + info_len = sizeof(info); + if (has_btf) { + info.nr_func_info = sub_prog_cnt; + info.func_info_rec_size = func_info_rec_size; + info.func_info = ptr_to_u64(func_infos); + } + + err = bpf_obj_get_info_by_fd(fd, &info, &info_len); + if (err) + goto out; + + /* Synthesize PERF_RECORD_KSYMBOL */ + for (i = 0; i < sub_prog_cnt; i++) { + const struct bpf_func_info *finfo; + const char *short_name = NULL; + const struct btf_type *t; + int name_len; + + *ksymbol_event = (struct ksymbol_event){ + .header = { + .type = PERF_RECORD_KSYMBOL, + .size = sizeof(struct ksymbol_event), + }, + .addr = prog_addrs[i], + .len = prog_lens[i], + .ksym_type = PERF_RECORD_KSYMBOL_TYPE_BPF, + .flags = 0, + }; + name_len = snprintf(ksymbol_event->name, KSYM_NAME_LEN, + "bpf_prog_"); + name_len += snprintf_hex(ksymbol_event->name + name_len, + KSYM_NAME_LEN - name_len, + prog_tags[i], BPF_TAG_SIZE); + if (has_btf) { + finfo = func_infos + i * info.func_info_rec_size; + t = btf__type_by_id(btf, finfo->type_id); + short_name = btf__name_by_offset(btf, t->name_off); + } else if (i == 0 && sub_prog_cnt == 1) { + /* no subprog */ + if (info.name[0]) + short_name = info.name; + } else + short_name = "F"; + if (short_name) + name_len += snprintf(ksymbol_event->name + name_len, + KSYM_NAME_LEN - name_len, + "_%s", short_name); + + ksymbol_event->header.size += PERF_ALIGN(name_len + 1, + sizeof(u64)); + err = perf_tool__process_synth_event(tool, event, + machine, process); + } + + /* Synthesize PERF_RECORD_BPF_EVENT */ + if (opts->bpf_event) { + *bpf_event = (struct bpf_event){ + .header = { + .type = PERF_RECORD_BPF_EVENT, + .size = sizeof(struct bpf_event), + }, + .type = PERF_BPF_EVENT_PROG_LOAD, + .flags = 0, + .id = info.id, + }; + memcpy(bpf_event->tag, prog_tags[i], BPF_TAG_SIZE); + err = perf_tool__process_synth_event(tool, event, + machine, process); + } + +out: + free(prog_tags); + free(prog_lens); + free(prog_addrs); + free(func_infos); + free(btf); + return err ? -1 : 0; +} + +int perf_event__synthesize_bpf_events(struct perf_tool *tool, + perf_event__handler_t process, + struct machine *machine, + struct record_opts *opts) +{ + union perf_event *event; + __u32 id = 0; + int err; + int fd; + + event = malloc(sizeof(event->bpf_event) + KSYM_NAME_LEN); + if (!event) + return -1; + while (true) { + err = bpf_prog_get_next_id(id, &id); + if (err) { + if (errno == ENOENT) { + err = 0; + break; + } + pr_err("can't get next program: %s%s", + strerror(errno), + errno == EINVAL ? " -- kernel too old?" : ""); + /* don't report error on old kernel */ + err = (errno == EINVAL) ? 0 : -1; + break; + } + fd = bpf_prog_get_fd_by_id(id); + if (fd < 0) { + pr_debug("Failed to get fd for prog_id %u\n", id); + continue; + } + + err = perf_event__synthesize_one_bpf_prog( + tool, process, machine, fd, event, opts); + close(fd); + if (err) + break; + } + free(event); + return err; +} diff --git a/tools/perf/util/bpf-event.h b/tools/perf/util/bpf-event.h index d5ca355dd298..38aee4040f12 100644 --- a/tools/perf/util/bpf-event.h +++ b/tools/perf/util/bpf-event.h @@ -8,4 +8,9 @@ int machine__process_bpf_event(struct machine *machine, union perf_event *event, struct perf_sample *sample); +int perf_event__synthesize_bpf_events(struct perf_tool *tool, + perf_event__handler_t process, + struct machine *machine, + struct record_opts *opts); + #endif