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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 A18C7C433E0 for ; Wed, 15 Jul 2020 05:29:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 732FD2068F for ; Wed, 15 Jul 2020 05:29:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="YqOjZ4HO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728413AbgGOF3F (ORCPT ); Wed, 15 Jul 2020 01:29:05 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:8986 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726034AbgGOF3E (ORCPT ); Wed, 15 Jul 2020 01:29:04 -0400 Received: from pps.filterd (m0001303.ppops.net [127.0.0.1]) by m0001303.ppops.net (8.16.0.42/8.16.0.42) with SMTP id 06F5R3gH031306 for ; Tue, 14 Jul 2020 22:29:03 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.com; h=from : to : cc : subject : date : message-id : mime-version : content-transfer-encoding : content-type; s=facebook; bh=jBPZIxmT9Tkpkif76heASl4sVSO1vN4U8creO7C5kTw=; b=YqOjZ4HO45MXyBDGi3PDQusGNeZmVI9uOeefacBEFlS6w6nB3LC9BQDI92djT5OrwI2F OpIUgUh6KNSYN+m6lE+/P99StWAKnjR3G4MalttSSfegRqoTYke0pIf1Cm+W/DoH1L79 ZCvF6+QVNa9I4rdErCBu1GRHu/WBNjZgwaM= Received: from mail.thefacebook.com ([163.114.132.120]) by m0001303.ppops.net with ESMTP id 32793m9fuf-5 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Tue, 14 Jul 2020 22:29:03 -0700 Received: from intmgw002.03.ash8.facebook.com (2620:10d:c085:208::11) by mail.thefacebook.com (2620:10d:c085:21d::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Tue, 14 Jul 2020 22:29:02 -0700 Received: by devbig006.ftw2.facebook.com (Postfix, from userid 4523) id 72EA162E52DD; Tue, 14 Jul 2020 22:26:04 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Song Liu Smtp-Origin-Hostname: devbig006.ftw2.facebook.com To: , , CC: , , , , , , , Song Liu Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v2 bpf-next 0/2] bpf: fix stackmap on perf_events with PEBS Date: Tue, 14 Jul 2020 22:25:59 -0700 Message-ID: <20200715052601.2404533-1-songliubraving@fb.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-07-15_02:2020-07-15,2020-07-15 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 impostorscore=0 malwarescore=0 mlxlogscore=978 lowpriorityscore=0 mlxscore=0 adultscore=0 phishscore=0 bulkscore=0 priorityscore=1501 clxscore=1015 suspectscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007150046 X-FB-Internal: deliver Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Calling get_perf_callchain() on perf_events from PEBS entries may cause unwinder errors. To fix this issue, perf subsystem fetches callchain earl= y, and marks perf_events are marked with __PERF_SAMPLE_CALLCHAIN_EARLY. Similar issue exists when BPF program calls get_perf_callchain() via helper functions. For more information about this issue, please refer to discussions in [1]. This set fixes this issue with helper proto bpf_get_stackid_pe and bpf_get_stack_pe. [1] https://lore.kernel.org/lkml/ED7B9430-6489-4260-B3C5-9CFA2E3AA87A@fb.= com/ Changes v1 =3D> v2: 1. Simplify the design and avoid introducing new helper function. (Andrii= ) Song Liu (2): bpf: separate bpf_get_[stack|stackid] for perf events BPF selftests/bpf: add callchain_stackid include/linux/bpf.h | 2 + kernel/bpf/stackmap.c | 204 ++++++++++++++++-- kernel/trace/bpf_trace.c | 4 +- .../bpf/prog_tests/perf_event_stackmap.c | 120 +++++++++++ .../selftests/bpf/progs/perf_event_stackmap.c | 64 ++++++ 5 files changed, 374 insertions(+), 20 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/perf_event_sta= ckmap.c create mode 100644 tools/testing/selftests/bpf/progs/perf_event_stackmap= .c -- 2.24.1