From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,PDS_BAD_THREAD_QP_64, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1959C48BDF for ; Thu, 24 Jun 2021 04:54:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AEEFB613CE for ; Thu, 24 Jun 2021 04:54:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230505AbhFXE5A (ORCPT ); Thu, 24 Jun 2021 00:57:00 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:40322 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230392AbhFXE4t (ORCPT ); Thu, 24 Jun 2021 00:56:49 -0400 Received: from pps.filterd (m0109331.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 15O4rQBw014567; Wed, 23 Jun 2021 21:54:14 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=facebook; bh=Vf7Q48AAZ9LwEXSFESWz/6EY+72owziL0QshIlqU46I=; b=EJIOBRwuPWex2pjz58XkfnphjvYjFoYCL05ReZAFLyrETkBGgBs+xi3u727lguwc7THA 1lXHPnMqlfcmSSDAMp8JYbwPUI4VVBfrK5evY2w4LO/jeFrsz1Kj8URPvwMJ0ydTYKv+ tXPA4nX+JdeIhi+lDjm/hw3siRPSw+GaiR4= Received: from mail.thefacebook.com ([163.114.132.120]) by mx0a-00082601.pphosted.com with ESMTP id 39cbpuanw6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 23 Jun 2021 21:54:13 -0700 Received: from NAM04-DM6-obe.outbound.protection.outlook.com (100.104.98.9) by o365-in.thefacebook.com (100.104.94.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Wed, 23 Jun 2021 21:54:12 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=G6KAcnG0L8uv3ZtVw624lPGEFnQndiHig1z3hKuIp/nOPSvUVqt/X3Is0f9Zcn5n+d4VFAYXhj8qjBpHuGmhvD35a+29IZgl5XhD6eqmx+d4TaQKQfawQQYw+k2mqHwhM2W8IEPVZET+/iAmUcnokm0lxbsQnrfSbXMW5954yE+s+r4aZNXB9DoLdc4l5XXlzGwatF9DtfGDvTuewg7KxnbeEIrKrImlK5Lh34gev+JUeGPT0cq1WHkmaYbQeIAUSdycEw+7cIgca5WEG7gRFn0+J99fa+3d6aMcis+RooegLbK2H3ICi3Um5kHhJrpbSpX5FOIKHBahSTThgV3UFg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Vf7Q48AAZ9LwEXSFESWz/6EY+72owziL0QshIlqU46I=; b=oW+6goV39lCStf0vAonh6msmz9rHGUhd3qRmoOa5zm/r4J+gMSYjOQZ0mrQ/803O1SuYnuxW5ycNzuZvcpx/6k498Fl/Hj1lEedtE2kj80ZRSqNmDwCOBqYm6XjG/k68/IMIde26BfJfX6ebUxh6OQqtp/ZthpJVw91gLwZ9TYzYJ35rkQMGVGPSQNylnGTmA3LvyC/yyMJ0ka7CEilCfuhZcRNfYgivXNh3vUMTH34AAJcz3RjdZrSD22H2w07ENlui97/5t5MwFmHKs88dbBF5y/r4DFZV2ETYlwYHFPRQZ9o69hYS+sLKQGv+XgpHIoL6PbpOD0Ng8uAv4hJhcQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=fb.com; dmarc=pass action=none header.from=fb.com; dkim=pass header.d=fb.com; arc=none Received: from BYAPR15MB2999.namprd15.prod.outlook.com (2603:10b6:a03:fa::12) by BYAPR15MB4119.namprd15.prod.outlook.com (2603:10b6:a02:cd::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4242.22; Thu, 24 Jun 2021 04:54:11 +0000 Received: from BYAPR15MB2999.namprd15.prod.outlook.com ([fe80::38d3:cc71:bca8:dd2a]) by BYAPR15MB2999.namprd15.prod.outlook.com ([fe80::38d3:cc71:bca8:dd2a%5]) with mapi id 15.20.4173.038; Thu, 24 Jun 2021 04:54:11 +0000 From: Song Liu To: Namhyung Kim CC: Arnaldo Carvalho de Melo , Jiri Olsa , Ingo Molnar , Peter Zijlstra , LKML , Andi Kleen , Ian Rogers , Stephane Eranian Subject: Re: [PATCH 3/3] perf stat: Enable BPF counter with --for-each-cgroup Thread-Topic: [PATCH 3/3] perf stat: Enable BPF counter with --for-each-cgroup Thread-Index: AQHXZzX6p6bVUgsBlEW05HtuW1Dxiasim4OA Date: Thu, 24 Jun 2021 04:54:10 +0000 Message-ID: References: <20210622071221.128271-1-namhyung@kernel.org> <20210622071221.128271-4-namhyung@kernel.org> In-Reply-To: <20210622071221.128271-4-namhyung@kernel.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-mailer: Apple Mail (2.3654.100.0.2.22) authentication-results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=fb.com; x-originating-ip: [2620:10d:c090:400::5:cce7] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 79b1cfa3-3218-47de-f9a0-08d936cc1b79 x-ms-traffictypediagnostic: BYAPR15MB4119: x-microsoft-antispam-prvs: x-fb-source: Internal x-ms-oob-tlc-oobclassifiers: OLM:3826; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR15MB2999.namprd15.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(39860400002)(376002)(346002)(366004)(396003)(136003)(33656002)(122000001)(2906002)(8676002)(64756008)(38100700002)(316002)(6486002)(53546011)(8936002)(83380400001)(186003)(6506007)(4326008)(71200400001)(66556008)(478600001)(66946007)(2616005)(66476007)(5660300002)(86362001)(6512007)(36756003)(6916009)(54906003)(66446008)(76116006)(45980500001);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?VbPTSwiqZIvV4J/OwQTDfCc4W4rbr0FquWYP7HSCgtE1+qbeEHQEwGEJ/hws?= =?us-ascii?Q?cpNpIM6LpS744VIKbaNh6xGLuHJG5b7WYxEKhhg/Lf+BSo5ZgJGk2QchkCX0?= =?us-ascii?Q?XPWJjMxObnmRhpjavl/bNs+Q+iBYC37Z6UaHvr6SdivctwYem1+cjKnF238m?= =?us-ascii?Q?zQq7B8F48m25Bg2nG8LuGcDutwcyKJ8K358leKVm9AEjsFEpXnnKnhkE0pHt?= =?us-ascii?Q?ooCAiMnEqtX4+aMgUbfr/Ib4v0MdwyscWr0wLgwro7dIko5bxWI+PkngUIag?= =?us-ascii?Q?2ffa5gcL4eVg+zTNlyt47n6doMAqqrYu8c55XY7xr7Bwibvy1YNb+yn1ajqd?= =?us-ascii?Q?m17Nh1MpIrj1Zzn/9muD3Brv9WiOL0DNeGoxQ61hBAqCr+h5SHPVzuu50KKX?= =?us-ascii?Q?HGgLhKznX3kapQNFPAV9mcbyLWdpML4AtWf2Siy55jzsiVAEor3q/WV6G85x?= =?us-ascii?Q?V7faaca3kLyh7MU5VGUR2lABZRIG0A5D50l8KJ8rytRa/wihMNQkL7Ikh+S0?= =?us-ascii?Q?qnK5Hz8RgNWl9JzkaCt+JdlL7EpHf+E6+J3bpiQOWOZ8F16e9Z5jiWrm2D8P?= =?us-ascii?Q?rXuZ5Lo1OAk5tAGCp+BBPr2aj9Pe6m4dglE6W+SfbItYy0pC9yRr1VPsrhRN?= =?us-ascii?Q?Ha8Pcbcb5Md9+tZ5Cnu6wqhDLCx9D6+74W4Cl9iXvXT50twoiz7PfMsustjm?= =?us-ascii?Q?Bxw+PDN8+fkKHssHry1b4AtndSAuvA85Yl6BpUqTuX/WCJZ5DWIKOWQS/14N?= =?us-ascii?Q?uer5uWYXatWfV1c34IW0Gh9tLsFQc9v0lRgyeig+RzpivY7R31zCtQXKs9wb?= =?us-ascii?Q?8RR8LL77WSaOGZJXM5MqsPFsJDt7R8opi2myKYgLlM/p58OqAgIu/kPJuj6c?= =?us-ascii?Q?edhh4nLMS1v2aEIDfcZhmz21tGWBAdfmZVqR0ttTGC8obGuacFPj1iZXQeKd?= =?us-ascii?Q?pi4OLSRibRuDwm4H6Rj0SAc6di4H8MD6oHTKrgU4IJmvWAMufKFFlJzx48ZG?= =?us-ascii?Q?9f1xEaZrt1eoP4qAXciI1DqfCZEhYrFFm6pxT5Vl4VuUQ7cdHAHzHi9QO1pm?= =?us-ascii?Q?JqOKhiDMRiEmCw0ed3n9x61j7m2ngKra3FZaFgLLfR/gabjEQRYk2GsYDqlC?= =?us-ascii?Q?b8Ou0rysQ+Pbfo+EuR0VdlOwC4i0jtAafk0C7ACxpLmsWhJY5l1ZWWDUX+OP?= =?us-ascii?Q?vZU10ADO7FjdimEh6lySv8o7RzYAKQ+xajGmnjMXUjD3+etRaaHpOII7j58D?= =?us-ascii?Q?FEYpFHdn0I6Sj99M7kUYEBj3CO2rzfS9qCIb7UTP3FVC3svgpB4kGL7MUtqS?= =?us-ascii?Q?Hi1SesBD84fyL18I9KCJo9/dcGiOAWIhn8y9K4tmMYlKPbjh6AeXcf0/fZxv?= =?us-ascii?Q?SQBsgzw=3D?= x-ms-exchange-transport-forked: True Content-Type: text/plain; charset="us-ascii" Content-ID: <2B7CE2AB57E3D445B60D75895BDB4CFE@namprd15.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BYAPR15MB2999.namprd15.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 79b1cfa3-3218-47de-f9a0-08d936cc1b79 X-MS-Exchange-CrossTenant-originalarrivaltime: 24 Jun 2021 04:54:11.0083 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: 2sWlJm9nEcRAtxJ7kVucyyXROlbnQNZPcL5bTlpBcIct+rnS6aywLmmb4TlacheX3TJh1akTBK3qoganXiKu9g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB4119 X-OriginatorOrg: fb.com X-Proofpoint-ORIG-GUID: K5LPpaWNzGBKls8PqCsK9TTdqmk3Dz_T X-Proofpoint-GUID: K5LPpaWNzGBKls8PqCsK9TTdqmk3Dz_T X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-06-24_03:2021-06-23,2021-06-24 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 phishscore=0 mlxscore=0 bulkscore=0 impostorscore=0 spamscore=0 malwarescore=0 adultscore=0 priorityscore=1501 clxscore=1015 suspectscore=0 mlxlogscore=999 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2106240026 X-FB-Internal: deliver Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Jun 22, 2021, at 12:12 AM, Namhyung Kim wrote: >=20 > Recently bperf was added to use BPF to count perf events for various > purposes. This is an extension for the approach and targetting to > cgroup usages. >=20 > Unlike the other bperf, it doesn't share the events with other > processes but it'd reduce unnecessary events (and the overhead of > multiplexing) for each monitored cgroup within the perf session. >=20 > When --for-each-cgroup is used with --bpf-counters, it will open > cgroup-switches event per cpu internally and attach the new BPF > program to read given perf_events and to aggregate the results for > cgroups. It's only called when task is switched to a task in a > different cgroup. >=20 > Cc: Song Liu > Signed-off-by: Namhyung Kim > --- > tools/perf/Makefile.perf | 7 +- > tools/perf/util/Build | 1 + > tools/perf/util/bpf_counter.c | 5 + > tools/perf/util/bpf_counter_cgroup.c | 337 ++++++++++++++++++++ > tools/perf/util/bpf_skel/bperf_cgroup.bpf.c | 207 ++++++++++++ > tools/perf/util/cgroup.c | 2 + > tools/perf/util/cgroup.h | 1 + > 7 files changed, 559 insertions(+), 1 deletion(-) > create mode 100644 tools/perf/util/bpf_counter_cgroup.c > create mode 100644 tools/perf/util/bpf_skel/bperf_cgroup.bpf.c >=20 > diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf > index e47f04e5b51e..786cba8f3798 100644 > --- a/tools/perf/Makefile.perf > +++ b/tools/perf/Makefile.perf > @@ -1015,6 +1015,7 @@ SKEL_OUT :=3D $(abspath $(OUTPUT)util/bpf_skel) > SKEL_TMP_OUT :=3D $(abspath $(SKEL_OUT)/.tmp) > SKELETONS :=3D $(SKEL_OUT)/bpf_prog_profiler.skel.h > SKELETONS +=3D $(SKEL_OUT)/bperf_leader.skel.h $(SKEL_OUT)/bperf_follower= .skel.h > +SKELETONS +=3D $(SKEL_OUT)/bperf_cgroup.skel.h >=20 > ifdef BUILD_BPF_SKEL > BPFTOOL :=3D $(SKEL_TMP_OUT)/bootstrap/bpftool > @@ -1032,7 +1033,11 @@ $(SKEL_TMP_OUT)/%.bpf.o: util/bpf_skel/%.bpf.c $(L= IBBPF) | $(SKEL_TMP_OUT) > $(QUIET_CLANG)$(CLANG) -g -O2 -target bpf -Wall -Werror $(BPF_INCLUDE) \ > -c $(filter util/bpf_skel/%.bpf.c,$^) -o $@ && $(LLVM_STRIP) -g $@ >=20 > -$(SKEL_OUT)/%.skel.h: $(SKEL_TMP_OUT)/%.bpf.o | $(BPFTOOL) > +$(SKEL_OUT)/vmlinux.h: > + $(MAKE) -C ../bpf/bpftool OUTPUT=3D$(SKEL_TMP_OUT)/ $(SKEL_TMP_OUT)/vml= inux.h We build bpftool with $(BPFTOOL), which is a few lines above.=20 Can we reuse some of that?=20 > + $(Q)mv $(SKEL_TMP_OUT)/vmlinux.h $(SKEL_OUT)/vmlinux.h > + > +$(SKEL_OUT)/%.skel.h: $(SKEL_TMP_OUT)/%.bpf.o $(SKEL_OUT)/vmlinux.h | $(= BPFTOOL) > $(QUIET_GENSKEL)$(BPFTOOL) gen skeleton $< > $@ >=20 > bpf-skel: $(SKELETONS) > diff --git a/tools/perf/util/Build b/tools/perf/util/Build > index 95e15d1035ab..700d635448ff 100644 > --- a/tools/perf/util/Build > +++ b/tools/perf/util/Build > @@ -140,6 +140,7 @@ perf-y +=3D clockid.o > perf-$(CONFIG_LIBBPF) +=3D bpf-loader.o > perf-$(CONFIG_LIBBPF) +=3D bpf_map.o > perf-$(CONFIG_PERF_BPF_SKEL) +=3D bpf_counter.o > +perf-$(CONFIG_PERF_BPF_SKEL) +=3D bpf_counter_cgroup.o > perf-$(CONFIG_BPF_PROLOGUE) +=3D bpf-prologue.o > perf-$(CONFIG_LIBELF) +=3D symbol-elf.o > perf-$(CONFIG_LIBELF) +=3D probe-file.o > diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.= c > index 974f10e356f0..7812c5d9b826 100644 > --- a/tools/perf/util/bpf_counter.c > +++ b/tools/perf/util/bpf_counter.c > @@ -22,6 +22,7 @@ > #include "evsel.h" > #include "evlist.h" > #include "target.h" > +#include "cgroup.h" > #include "cpumap.h" > #include "thread_map.h" >=20 > @@ -792,6 +793,8 @@ struct bpf_counter_ops bperf_ops =3D { > .destroy =3D bperf__destroy, > }; >=20 > +extern struct bpf_counter_ops bperf_cgrp_ops; > + > static inline bool bpf_counter_skip(struct evsel *evsel) > { > return list_empty(&evsel->bpf_counter_list) && > @@ -809,6 +812,8 @@ int bpf_counter__load(struct evsel *evsel, struct tar= get *target) > { > if (target->bpf_str) > evsel->bpf_counter_ops =3D &bpf_program_profiler_ops; > + else if (cgrp_event_expanded && target->use_bpf) > + evsel->bpf_counter_ops =3D &bperf_cgrp_ops; > else if (target->use_bpf || evsel->bpf_counter || > evsel__match_bpf_counter_events(evsel->name)) > evsel->bpf_counter_ops =3D &bperf_ops; [...] > + > +#include "bpf_skel/bperf_cgroup.skel.h" > + > +static struct perf_event_attr cgrp_switch_attr =3D { > + .type =3D PERF_TYPE_SOFTWARE, > + .config =3D PERF_COUNT_SW_CGROUP_SWITCHES, > + .size =3D sizeof(cgrp_switch_attr), > + .sample_period =3D 1, > + .disabled =3D 1, > +}; > + > +static struct evsel *cgrp_switch; > +static struct xyarray *cgrp_prog_fds; > +static struct bperf_cgroup_bpf *skel; > + > +#define FD(evt, cpu) (*(int *)xyarray__entry(evt->core.fd, cpu, 0)) > +#define PROG(cpu) (*(int *)xyarray__entry(cgrp_prog_fds, cpu, 0)) > + > +static void set_max_rlimit(void) > +{ > + struct rlimit rinf =3D { RLIM_INFINITY, RLIM_INFINITY }; > + > + setrlimit(RLIMIT_MEMLOCK, &rinf); > +} > + > +static __u32 bpf_link_get_prog_id(int fd) > +{ > + struct bpf_link_info link_info =3D {0}; > + __u32 link_info_len =3D sizeof(link_info); > + > + bpf_obj_get_info_by_fd(fd, &link_info, &link_info_len); > + return link_info.prog_id; > +} How about we move set_max_rlimit() and bpf_link_get_prog_id() to=20 a header so we don't have to duplicate it? > + > +static int bperf_load_program(struct evlist *evlist) > +{ > + struct bpf_link *link; > + struct evsel *evsel; > + struct cgroup *cgrp, *leader_cgrp; > + __u32 i, cpu, prog_id; > + int nr_cpus =3D evlist->core.all_cpus->nr; > + int map_size, map_fd; > + int prog_fd, err; > + > + skel =3D bperf_cgroup_bpf__open(); > + if (!skel) { > + pr_err("Failed to open cgroup skeleton\n"); > + return -1; > + } > + > + skel->rodata->num_cpus =3D nr_cpus; > + skel->rodata->num_events =3D evlist->core.nr_entries / nr_cgroups; > + > + BUG_ON(evlist->core.nr_entries % nr_cgroups !=3D 0); > + > + /* we need one copy of events per cpu for reading */ > + map_size =3D nr_cpus * evlist->core.nr_entries / nr_cgroups; > + bpf_map__resize(skel->maps.events, map_size); > + bpf_map__resize(skel->maps.cpu_idx, nr_cpus); > + bpf_map__resize(skel->maps.cgrp_idx, nr_cgroups); > + /* previous result is saved in a per-cpu array */ > + map_size =3D evlist->core.nr_entries / nr_cgroups; > + bpf_map__resize(skel->maps.prev_readings, map_size); > + /* cgroup result needs all events */ > + map_size =3D nr_cpus * evlist->core.nr_entries; > + bpf_map__resize(skel->maps.cgrp_readings, map_size); We are setting map_size back and forth here.=20 [...] > diff --git a/tools/perf/util/bpf_skel/bperf_cgroup.bpf.c b/tools/perf/uti= l/bpf_skel/bperf_cgroup.bpf.c > new file mode 100644 > index 000000000000..6d74e93dd1f5 > --- /dev/null > +++ b/tools/perf/util/bpf_skel/bperf_cgroup.bpf.c > @@ -0,0 +1,207 @@ > +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +// Copyright (c) 2021 Facebook > +// Copyright (c) 2021 Google > +#include "vmlinux.h" > +#include > +#include > +#include > + > +#define MAX_LEVELS 10 // max cgroup hierarchy level: arbitrary > +#define MAX_EVENTS 32 // max events per cgroup: arbitrary > + > +// NOTE: many of map and global data will be modified before loading > +// from the userspace (perf tool) using the skeleton helpers. > + > +// single set of global perf events to measure > +struct { > + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(int)); > + __uint(max_entries, 1); > +} events SEC(".maps"); > + > +// from logical cpu number to event index > +// useful when user wants to count subset of cpus > +struct { > + __uint(type, BPF_MAP_TYPE_HASH); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(__u32)); > + __uint(max_entries, 1); > +} cpu_idx SEC(".maps"); How about we make cpu_idx a percpu array and use 0,1 for=20 disable/enable profiling on this cpu?=20 > + > +// from cgroup id to event index > +struct { > + __uint(type, BPF_MAP_TYPE_HASH); > + __uint(key_size, sizeof(__u64)); > + __uint(value_size, sizeof(__u32)); > + __uint(max_entries, 1); > +} cgrp_idx SEC(".maps"); > + > +// per-cpu event snapshots to calculate delta > +struct { > + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(struct bpf_perf_event_value)); > +} prev_readings SEC(".maps"); > + > +// aggregated event values for each cgroup > +// will be read from the user-space > +struct { > + __uint(type, BPF_MAP_TYPE_ARRAY); > + __uint(key_size, sizeof(__u32)); > + __uint(value_size, sizeof(struct bpf_perf_event_value)); > +} cgrp_readings SEC(".maps"); Maybe also make this a percpu array? This should make the BPF program faster.=20 > + > +const volatile __u32 num_events =3D 1; > +const volatile __u32 num_cpus =3D 1; > + > +int enabled =3D 0; > +int use_cgroup_v2 =3D 0; > + [...]