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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable 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 57B67C282DD for ; Wed, 22 May 2019 14:53:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 201D320879 for ; Wed, 22 May 2019 14:53:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=fb.com header.i=@fb.com header.b="LHVMc+/T"; dkim=pass (1024-bit key) header.d=fb.onmicrosoft.com header.i=@fb.onmicrosoft.com header.b="tMVyY9n0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729727AbfEVOxC (ORCPT ); Wed, 22 May 2019 10:53:02 -0400 Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:37148 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728450AbfEVOxB (ORCPT ); Wed, 22 May 2019 10:53:01 -0400 Received: from pps.filterd (m0148460.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4MEiSk5015190; Wed, 22 May 2019 07:51:23 -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=sKbDtBGnVKIRUaCAczgStNECUOVI180S+3MwhCS8lFI=; b=LHVMc+/Tw/xPFyA8DqbDJADpMXcHdwQ+9kPZs5iNgMKVElJAl6msaC6n2mlJ/c4f1bn8 DAlzFBQjtpyt1qJhyTuib1MmzuUz7stRYpMwIHhe+ce5QfiYvT3ybbuKrkee2mhcx8C4 +4qoCD51avfjv8ePMFyU5kLi9OPotCIXJTU= Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2smr4jty00-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT); Wed, 22 May 2019 07:51:23 -0700 Received: from ash-exopmbx101.TheFacebook.com (2620:10d:c0a8:82::b) by ash-exhub103.TheFacebook.com (2620:10d:c0a8:82::c) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Wed, 22 May 2019 07:51:22 -0700 Received: from ash-exhub101.TheFacebook.com (2620:10d:c0a8:82::e) by ash-exopmbx101.TheFacebook.com (2620:10d:c0a8:82::b) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Wed, 22 May 2019 07:51:22 -0700 Received: from NAM05-BY2-obe.outbound.protection.outlook.com (100.104.31.183) by o365-in.thefacebook.com (100.104.35.173) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.1713.5 via Frontend Transport; Wed, 22 May 2019 07:51:20 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=fb.onmicrosoft.com; s=selector1-fb-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=sKbDtBGnVKIRUaCAczgStNECUOVI180S+3MwhCS8lFI=; b=tMVyY9n0OBZG+Fk8wHU+QAOjOlCB5iYK/M0qLMex80YU3TEyKd9DuCYJverCDH42qKiiqag+X7aMELAOo0PpulwlD7tUaxmEEKbWI9+xTFGXALuOfE1EjYN5w17HcQfTGoG0OyMDtpX/YylI9F4Oq+uqvnzOn+QgBymy+najJ+8= Received: from BYAPR15MB2501.namprd15.prod.outlook.com (52.135.196.11) by BYAPR15MB3384.namprd15.prod.outlook.com (20.179.59.17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1900.22; Wed, 22 May 2019 14:49:08 +0000 Received: from BYAPR15MB2501.namprd15.prod.outlook.com ([fe80::140e:9c62:f2d3:7f27]) by BYAPR15MB2501.namprd15.prod.outlook.com ([fe80::140e:9c62:f2d3:7f27%7]) with mapi id 15.20.1900.020; Wed, 22 May 2019 14:49:08 +0000 From: Alexei Starovoitov To: Peter Zijlstra , Kairui Song CC: Song Liu , lkml , Kernel Team , Josh Poimboeuf , Alexei Starovoitov , Daniel Borkmann , "bpf@vger.kernel.org" Subject: Re: Getting empty callchain from perf_callchain_kernel() Thread-Topic: Getting empty callchain from perf_callchain_kernel() Thread-Index: AQHVDEJXYtrotGS6bU+cxwR7BKWjbKZu8J8AgAAG+ICAAAFQgIAAD2QAgAO6dwCABHK6gIAADP6A Date: Wed, 22 May 2019 14:49:07 +0000 Message-ID: References: <3CD3EE63-0CD2-404A-A403-E11DCF2DF8D9@fb.com> <20190517074600.GJ2623@hirez.programming.kicks-ass.net> <20190517081057.GQ2650@hirez.programming.kicks-ass.net> <20190517091044.GM2606@hirez.programming.kicks-ass.net> <20190522140233.GC16275@worktop.programming.kicks-ass.net> In-Reply-To: <20190522140233.GC16275@worktop.programming.kicks-ass.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: CO2PR07CA0072.namprd07.prod.outlook.com (2603:10b6:100::40) To BYAPR15MB2501.namprd15.prod.outlook.com (2603:10b6:a02:88::11) x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [2620:10d:c090:180::9fb6] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 0b423561-71ac-48fe-3bb5-08d6dec4a3f6 x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600141)(711020)(4605104)(2017052603328)(7193020);SRVR:BYAPR15MB3384; x-ms-traffictypediagnostic: BYAPR15MB3384: x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:6108; x-forefront-prvs: 0045236D47 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(346002)(136003)(396003)(366004)(376002)(39860400002)(189003)(199004)(7736002)(305945005)(36756003)(6246003)(54906003)(99286004)(68736007)(14454004)(4326008)(6116002)(478600001)(25786009)(76176011)(2906002)(446003)(486006)(186003)(31686004)(52116002)(476003)(2616005)(386003)(6506007)(53546011)(11346002)(53936002)(46003)(102836004)(316002)(8676002)(6486002)(81156014)(31696002)(71190400001)(71200400001)(86362001)(81166006)(73956011)(256004)(66946007)(6436002)(5024004)(110136005)(5660300002)(229853002)(8936002)(66476007)(66556008)(64756008)(66446008)(6512007);DIR:OUT;SFP:1102;SCL:1;SRVR:BYAPR15MB3384;H:BYAPR15MB2501.namprd15.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;MX:1;A:1; received-spf: None (protection.outlook.com: fb.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: sa+SP/LIBVUKgSLWeUKvRj0++KKVopvhhvUy8QAn0iaNyiK4WIfxi1veGtoM89mx817l/TfF7dM/aEGGVn3gE8YWNYmwFD7pU9+fej9UenCEHMs9MsBFJKMT/NifleBnYH9RxTtyljpWel5q3cQXQzyRfuGnlDNR3pOxDqbQ0jIxtafv9eYsBQtF7r7edz3e8IiFDgiNjPw8k6hedoplcSjGMDYXOhNBeaFps+E3z6MjhMx0HSkuGj1UU5ppeL2rQKbL+wEk6jztUVyBNEnpxJZUhxI3YZHK3+Q8iKVKEUxC4vTWMUBYt+SGZvK/X9XPx5SWqJe7Wbyb3QJrFCS4twzxVnS2JCOrW7xH5hj6zvGS99UZCvoUXmgkEW13wrropIKisk8CmXx5ZsdPmJV4AaCDc8np8W+tP+c2phVjdhY= Content-Type: text/plain; charset="utf-8" Content-ID: <2F061B130DBC5948B404DEA6DB676E69@namprd15.prod.outlook.com> Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 0b423561-71ac-48fe-3bb5-08d6dec4a3f6 X-MS-Exchange-CrossTenant-originalarrivaltime: 22 May 2019 14:49:08.0274 (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-Transport-CrossTenantHeadersStamped: BYAPR15MB3384 X-OriginatorOrg: fb.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-22_07:,, 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-1905220105 X-FB-Internal: deliver Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org T24gNS8yMi8xOSA3OjAyIEFNLCBQZXRlciBaaWpsc3RyYSB3cm90ZToNCj4gDQo+PiBJZiB0aGUg dW53aW5kZXIgY291bGQgdHJhY2UgYmFjayB0aHJvdWdoIHRoZSBicGYgZnVuYyBjYWxsIHRoZW4g dGhlcmUNCj4+IHdpbGwgYmUgbm8gc3VjaCBwcm9ibGVtLg0KPiANCj4gV2h5IGNvdWxkbid0IGl0 IHRyYWNlIGJhY2sgdGhyb3VnaCB0aGUgYnBmIHN0dWZmPyBBbmQgaG93IGNhbiB3ZSBmaXgNCj4g dGhhdD8NCg0KTW9zdCBvZiB0aGUgdGltZSB0aGVyZSBpcyBubyAndHJhY2luZyB0aHJvdWdoIGJw ZiBzdHVmZicuDQpicGYgaW5mcmEgaXMgcHJlc2VydmluZyAncHRfcmVncyonIHRoYXQgd2FzIGNv bGxlY3RlZCBiZWZvcmUNCmFueSBicGYgdGhpbmdzIHN0YXJ0IGV4ZWN1dGluZy4NClRoZSByZWFz b24gaXMgdGhhdCBicGYgY2FuIGJlIGV4ZWN1dGVkIHZpYSBpbnRlcnByZXRlciBhbmQNCmRpcmVj dGx5IHdoZW4gSklUZWQuDQpJbiBib3RoIGNhc2VzIGNvbGxlY3RlZCBzdGFjayB0cmFjZXMgc2hv dWxkIGJlIHRoZSBzYW1lIG9yDQppdCdzIGNvbmZ1c2luZyB0aGUgdXNlcnMgYW5kIHRoZXkgY2Fu bm90IGNvbXBlbnNhdGUgZm9yIHN1Y2gNCmRpZmZlcmVuY2UuDQoNClRoZSBvbmx5IGV4Y2VwdGlv biBpcyByYXdfdHJhY2Vwb2ludCwgc2luY2UgaXQncyB0aGUgbW9zdA0KbWluaW1hbGlzdGljIHdh eSBvZiBjYWxsaW5nIGJwZiBhbmQga2VybmVsIHNpZGUgZG9lc24ndCBkbw0KYW55dGhpbmcgYmVm b3JlIGNhbGxpbmcgaW50byBicGYuDQpPbmx5IGluIHN1Y2ggY2FzZSBicGYgc2lkZSBoYXMgdG8g Y2FsbCBwZXJmX2ZldGNoX2NhbGxlcl9yZWdzKCkuDQpTZWUgYnBmX2dldF9zdGFja2lkX3Jhd190 cCgpLg0KQnV0IHRoaXMgdGVzdCBjYXNlIGlzIGFjdHVhbGx5IHdvcmtpbmchDQpJdCdzIGNvdmVy ZWQgYnkgcHJvZ190ZXN0cy9zdGFja3RyYWNlX21hcF9yYXdfdHAuYyBhbmQNCml0IHBhc3Nlcy4N ClRoZSBvbmUgdGhhdCBpcyBicm9rZW4gaXMgcHJvZ190ZXN0cy9zdGFja3RyYWNlX21hcC5jDQpU aGVyZSB3ZSBhdHRhY2ggYnBmIHRvIHN0YW5kYXJkIHRyYWNlcG9pbnQgd2hlcmUNCmtlcm5lbCBz dXBwb3NlIHRvIGNvbGxlY3QgcHRfcmVncyBiZWZvcmUgY2FsbGluZyBpbnRvIGJwZi4NCkFuZCB0 aGF0J3Mgd2hhdCBicGZfZ2V0X3N0YWNraWRfdHAoKSBpcyBkb2luZy4NCkl0IHBhc3NlcyBwdF9y ZWdzICh0aGF0IHdhcyBjb2xsZWN0ZWQgYmVmb3JlIGFueSBicGYpDQppbnRvIGJwZl9nZXRfc3Rh Y2tpZCgpIHdoaWNoIGNhbGxzIGdldF9wZXJmX2NhbGxjaGFpbigpLg0KU2FtZSB0aGluZyB3aXRo IGtwcm9iZXMsIHVwcm9iZXMuDQoNCg0K