From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1204544-1520119275-2-14314021738061768848 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES unknown, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='com', MailFrom='org', XOriginatingCountry='US' X-Spam-charsets: plain='iso-8859-1' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1520119275; b=RaB6fKeGHYGFpc+IMrN17u3a0hV/JIJ6lQlgGSH644oFgMU QCV74nnwSE40ZErMZvo4KKdod9aOOHjEuobO2glU6/BINZ0wu3K74/lfzXa2C2dW KrsYZ88vZ+c7Lsd7h724xX8svLJ/q9/Z33GBUuP9uqOm819aD/1bU60spo+5fwNH IsZp/LBmsvJd6LyhvLrJJC+Nv4hFjFdAUBSEnfb4yfD3W6qtgF4oA8hbD+z4OQ71 H8FnEyzjefRl6cstAm9LcxgsdoavfuvKE1gAKpieojRXzXjnkfI1qxdO+bp6aZ2G 6uEcwVC/y9Mi5xk/Z4OUguMBezFCX3vOuX0bu3Q== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :references:in-reply-to:content-type:content-transfer-encoding :mime-version:sender:list-id; s=arctest; t=1520119275; bh=fponOK K/5WIOaqU94owvuW31e6lUE66U6gV7kHi4/Fc=; b=YNFNUPlDwIIlDhBdBgQzJG sk+urIkJWtrmSZwfvIMPqzsRk+F5+lQdj6pZdRTlr7FV1TyRx7bCBxEthPIZ3aM8 v5hmZQZnd6atN6SqpiX20qbQQaERxzVeNAdckKo+ynFZO0HAFHe/r+ukYTtnTgWJ 1FmGteiIo7oll8Ffl0jtB6h1n7NY4N7Tu+vtZUOdBUpxCS0thPrfPiEBXv/VOg6N Dth1g2XTNXejy49BjiWE1hCCy66XiIA60lhuAYJh/JxTXZWOXzwsB9CXgoFJ12Pf OIxg8srIQAc/DcLV+SZnVgqGvfPpp8nPC6EsUqp2eF/Zl8X8AC2+fAwa3/k2ypDg == ARC-Authentication-Results: i=1; mx5.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=USoFVOxY x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes Authentication-Results: mx5.messagingengine.com; arc=none (no signatures found); dkim=pass (1024-bit rsa key sha256) header.d=microsoft.com header.i=@microsoft.com header.b=USoFVOxY x-bits=1024 x-keytype=rsa x-algorithm=sha256 x-selector=selector1; dmarc=pass (p=reject,has-list-id=yes,d=none) header.from=microsoft.com; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=microsoft.com header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934778AbeCCWh4 (ORCPT ); Sat, 3 Mar 2018 17:37:56 -0500 Received: from mail-co1nam03on0134.outbound.protection.outlook.com ([104.47.40.134]:45128 "EHLO NAM03-CO1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S934750AbeCCWhy (ORCPT ); Sat, 3 Mar 2018 17:37:54 -0500 From: Sasha Levin To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" CC: Davidlohr Bueso , Davidlohr Bueso , "Paul E . McKenney" , Sasha Levin Subject: [PATCH AUTOSEL for 4.9 218/219] locking/locktorture: Fix num reader/writer corner cases Thread-Topic: [PATCH AUTOSEL for 4.9 218/219] locking/locktorture: Fix num reader/writer corner cases Thread-Index: AQHTsz8sRxoEQAjVN0mTV3/6ThEeCA== Date: Sat, 3 Mar 2018 22:30:03 +0000 Message-ID: <20180303222716.26640-218-alexander.levin@microsoft.com> References: <20180303222716.26640-1-alexander.levin@microsoft.com> In-Reply-To: <20180303222716.26640-1-alexander.levin@microsoft.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [52.168.54.252] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;MW2PR2101MB1100;6:Qj55tl1dBbcd4MLeF807QEYY1wOzoe/qWX0VhC0sNbYuKbCgRWKYqpfnNhkfOngYtB3cVhrTR62mQNXzkJ1u+Fz1Nx/CA649PgAB9/qxLesrysZSIvtD0TSfBEQYzhd8JGAt1bdorgrTsOo1KKYY7PfZIXTA0yGD1lW9Y8GochXjiOb79/PJjDOzROMy3cbDJFTadFCLSNv6pzqa1NmyoAR643Y2PWJAdQvdVEF/0S+Sk1BEj4nS1dRcUNzpJX6EwyoB+256dUvw8l55oinMrTKguUw5brHhIhQ9t02n/9oUMi13oJ/SCrq4m6m0EL//Hwd8jmGpfSNXm8YFeBexrbYDA+hNuU5c4nZpXmgtmvHlPtqcU8Jcea1z+P1FgoV+;5:+QjPtx458KsBONM61iPgcRiAS3scxEMCc0POgafJ6IF9TY/ARPfiYILczfC/4kQYXNxLdn+srbktKdKXQWJvZRIWRtWVt2IRC0U9w3nukRxUySNOCEfKgJWXnTg7SarEsBLMyfTEwDW0jsJtJesJtKAZinSAElOOZH+MS3RjLCg=;24:ce2c1hlcPgrX9Sd7+Y+6mwMXB1316ssOP3zG14aLL079G7QVcMrW9rw7zaaYdymmTjfoH1IhTtenAT64mkn8Fq2UqxerFnLrIju2Svydrko=;7:dBfKqDb6QlQXlO8WqjZZQDD5F+WJe7bxBrNDOUObM7l3O//1bD8CQGtprzaQpkCUCFLIUuX4It85b3YXQoWq8VjcoTo9CEIbfvDLNX/2tKLOxcHIDJo9vlQJodHlKVm5eWa5uYxm+Lct2Yo47AA2h7xwu/XXeOYnRnN//ydDpD7TO5B64PNOCviXY+cR9KGIJ6Tjiv4FTeJUzkMyTpvWB1aDVHgrVVvf87282Zlcf9TeHNHilGma99H2T4H7WWo1 x-ms-office365-filtering-ht: Tenant x-ms-office365-filtering-correlation-id: a02476cd-ac75-4740-ea4b-08d581576595 x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(7020095)(4652020)(4534165)(4627221)(201703031133081)(201702281549075)(48565401081)(5600026)(4604075)(3008032)(2017052603307)(7193020);SRVR:MW2PR2101MB1100; x-ms-traffictypediagnostic: MW2PR2101MB1100: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Alexander.Levin@microsoft.com; x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(28532068793085)(180628864354917)(89211679590171)(104084551191319); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(8211001083)(61425038)(6040501)(2401047)(5005006)(8121501046)(10201501046)(3002001)(3231220)(944501244)(52105095)(93006095)(93001095)(6055026)(61426038)(61427038)(6041288)(20161123560045)(20161123558120)(20161123562045)(201703131423095)(201702281528075)(20161123555045)(201703061421075)(201703061406153)(20161123564045)(6072148)(201708071742011);SRVR:MW2PR2101MB1100;BCL:0;PCL:0;RULEID:;SRVR:MW2PR2101MB1100; x-forefront-prvs: 0600F93FE1 x-forefront-antispam-report: SFV:NSPM;SFS:(10019020)(39380400002)(376002)(39860400002)(396003)(366004)(346002)(199004)(189003)(22452003)(97736004)(7736002)(5250100002)(105586002)(2906002)(6506007)(72206003)(66066001)(59450400001)(4326008)(305945005)(10290500003)(186003)(3280700002)(102836004)(2950100002)(6666003)(2501003)(478600001)(26005)(2900100001)(10090500001)(53936002)(8676002)(25786009)(81166006)(81156014)(575784001)(54906003)(86362001)(6436002)(106356001)(110136005)(68736007)(36756003)(316002)(6512007)(5660300001)(107886003)(8936002)(1076002)(6486002)(3660700001)(99286004)(76176011)(3846002)(86612001)(14454004)(6116002)(22906009)(217873001);DIR:OUT;SFP:1102;SCL:1;SRVR:MW2PR2101MB1100;H:MW2PR2101MB1034.namprd21.prod.outlook.com;FPR:;SPF:None;PTR:InfoNoRecords;A:1;MX:1;LANG:en; x-microsoft-antispam-message-info: 8OJ1xoKRvYayuf+c52tXLW3V+2MiZcomPghiD/fYoZwc5bJB/JbXcJkZzgwQYHhRkG6PLVajeP7VDPA6Ck7hymbqhRT/yh/NCvlM5KhCwy/orKBqf7NA8fK+rkgEhJRLmk71M4DSYpr63yTzLCVbMqxw3Im5eimKopcIWPRLwCw= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: a02476cd-ac75-4740-ea4b-08d581576595 X-MS-Exchange-CrossTenant-originalarrivaltime: 03 Mar 2018 22:30:03.2133 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW2PR2101MB1100 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: From: Davidlohr Bueso [ Upstream commit 2ce77d16db4240dd2e422fc0a5c26d3e2ec03446 ] Things can explode for locktorture if the user does combinations of nwriters_stress=3D0 nreaders_stress=3D0. Fix this by not assuming we always want to torture writer threads. Reported-by: Jeremy Linton Signed-off-by: Davidlohr Bueso Signed-off-by: Paul E. McKenney Reviewed-by: Jeremy Linton Tested-by: Jeremy Linton Signed-off-by: Sasha Levin --- kernel/locking/locktorture.c | 76 +++++++++++++++++++++++++---------------= ---- 1 file changed, 44 insertions(+), 32 deletions(-) diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index d3de04b12f8c..babc67cfed69 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -641,8 +641,7 @@ static void __torture_print_stats(char *page, { bool fail =3D 0; int i, n_stress; - long max =3D 0; - long min =3D statp[0].n_lock_acquired; + long max =3D 0, min =3D statp ? statp[0].n_lock_acquired : 0; long long sum =3D 0; =20 n_stress =3D write ? cxt.nrealwriters_stress : cxt.nrealreaders_stress; @@ -749,7 +748,7 @@ static void lock_torture_cleanup(void) * such, only perform the underlying torture-specific cleanups, * and avoid anything related to locktorture. */ - if (!cxt.lwsa) + if (!cxt.lwsa && !cxt.lrsa) goto end; =20 if (writer_tasks) { @@ -823,6 +822,13 @@ static int __init lock_torture_init(void) firsterr =3D -EINVAL; goto unwind; } + + if (nwriters_stress =3D=3D 0 && nreaders_stress =3D=3D 0) { + pr_alert("lock-torture: must run at least one locking thread\n"); + firsterr =3D -EINVAL; + goto unwind; + } + if (cxt.cur_ops->init) cxt.cur_ops->init(); =20 @@ -846,17 +852,19 @@ static int __init lock_torture_init(void) #endif =20 /* Initialize the statistics so that each run gets its own numbers. */ + if (nwriters_stress) { + lock_is_write_held =3D 0; + cxt.lwsa =3D kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KE= RNEL); + if (cxt.lwsa =3D=3D NULL) { + VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); + firsterr =3D -ENOMEM; + goto unwind; + } =20 - lock_is_write_held =3D 0; - cxt.lwsa =3D kmalloc(sizeof(*cxt.lwsa) * cxt.nrealwriters_stress, GFP_KER= NEL); - if (cxt.lwsa =3D=3D NULL) { - VERBOSE_TOROUT_STRING("cxt.lwsa: Out of memory"); - firsterr =3D -ENOMEM; - goto unwind; - } - for (i =3D 0; i < cxt.nrealwriters_stress; i++) { - cxt.lwsa[i].n_lock_fail =3D 0; - cxt.lwsa[i].n_lock_acquired =3D 0; + for (i =3D 0; i < cxt.nrealwriters_stress; i++) { + cxt.lwsa[i].n_lock_fail =3D 0; + cxt.lwsa[i].n_lock_acquired =3D 0; + } } =20 if (cxt.cur_ops->readlock) { @@ -873,19 +881,21 @@ static int __init lock_torture_init(void) cxt.nrealreaders_stress =3D cxt.nrealwriters_stress; } =20 - lock_is_read_held =3D 0; - cxt.lrsa =3D kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_KE= RNEL); - if (cxt.lrsa =3D=3D NULL) { - VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); - firsterr =3D -ENOMEM; - kfree(cxt.lwsa); - cxt.lwsa =3D NULL; - goto unwind; - } - - for (i =3D 0; i < cxt.nrealreaders_stress; i++) { - cxt.lrsa[i].n_lock_fail =3D 0; - cxt.lrsa[i].n_lock_acquired =3D 0; + if (nreaders_stress) { + lock_is_read_held =3D 0; + cxt.lrsa =3D kmalloc(sizeof(*cxt.lrsa) * cxt.nrealreaders_stress, GFP_K= ERNEL); + if (cxt.lrsa =3D=3D NULL) { + VERBOSE_TOROUT_STRING("cxt.lrsa: Out of memory"); + firsterr =3D -ENOMEM; + kfree(cxt.lwsa); + cxt.lwsa =3D NULL; + goto unwind; + } + + for (i =3D 0; i < cxt.nrealreaders_stress; i++) { + cxt.lrsa[i].n_lock_fail =3D 0; + cxt.lrsa[i].n_lock_acquired =3D 0; + } } } =20 @@ -915,12 +925,14 @@ static int __init lock_torture_init(void) goto unwind; } =20 - writer_tasks =3D kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0]= ), - GFP_KERNEL); - if (writer_tasks =3D=3D NULL) { - VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); - firsterr =3D -ENOMEM; - goto unwind; + if (nwriters_stress) { + writer_tasks =3D kzalloc(cxt.nrealwriters_stress * sizeof(writer_tasks[0= ]), + GFP_KERNEL); + if (writer_tasks =3D=3D NULL) { + VERBOSE_TOROUT_ERRSTRING("writer_tasks: Out of memory"); + firsterr =3D -ENOMEM; + goto unwind; + } } =20 if (cxt.cur_ops->readlock) { --=20 2.14.1