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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 8EE7AC433B4 for ; Thu, 29 Apr 2021 18:38:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5FD0A61441 for ; Thu, 29 Apr 2021 18:38:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240999AbhD2SjG (ORCPT ); Thu, 29 Apr 2021 14:39:06 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:10721 "EHLO mail3-relais-sop.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240974AbhD2SjG (ORCPT ); Thu, 29 Apr 2021 14:39:06 -0400 IronPort-HdrOrdr: =?us-ascii?q?A9a23=3AG/vuIKym4zfRSgGlnE3oKrPw571zdoIgy1kn?= =?us-ascii?q?xilNYDZeG/b0q+mFmvMH2RjozAsLUHY7ltyafIWGS3XQ9Zl6iLNhXouKcQH6tA?= =?us-ascii?q?KTQ71KwpDlx1TbcBHW0s54+eNef7NlCNv2ZGIbse/f7BOjG9gthPmLmZrHuc7k?= =?us-ascii?q?w31gTR5nZshbhm9EIzyGGU57ThQuP/YEPaebj/AsmxOQPVAebsG2HRA+PtT+mw?= =?us-ascii?q?=3D=3D?= X-IronPort-AV: E=Sophos;i="5.82,260,1613430000"; d="scan'208";a="380062492" Received: from palace.rsr.lip6.fr (HELO palace.lip6.fr) ([132.227.105.202]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-SHA; 29 Apr 2021 20:38:16 +0200 From: Julia Lawall To: Julia Lawall , Krzysztof Kozlowski , Mauro Carvalho Chehab Cc: kernel-janitors@vger.kernel.org, Gilles Muller , Nicolas Palix , Michal Marek , cocci@systeme.lip6.fr, linux-kernel@vger.kernel.org, "Rafael J . Wysocki" , Johan Hovold , Zhang Qilong , Jakub Kicinski , "Rafael J . Wysocki" Subject: [PATCH v4] coccinelle: api: semantic patch to use pm_runtime_resume_and_get Date: Thu, 29 Apr 2021 19:43:43 +0200 Message-Id: <20210429174343.2509714-1-Julia.Lawall@inria.fr> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org pm_runtime_get_sync keeps a reference count on failure, which can lead to leaks. pm_runtime_resume_and_get drops the reference count in the failure case. This rule very conservatively follows the definition of pm_runtime_resume_and_get to address the cases where the reference count is unlikely to be needed in the failure case. Specifically, the change is only done when pm_runtime_get_sync is followed immediately by an if and when the branch of the if is immediately a call to pm_runtime_put_noidle (like in the definition of pm_runtime_resume_and_get) or something that is likely a print statement followed by a pm_runtime_put_noidle call. The patch case appears somewhat more complicated, because it also deals with the cases where {}s need to be removed. pm_runtime_resume_and_get was introduced in commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter") Signed-off-by: Julia Lawall Acked-by: Rafael J. Wysocki --- v5: print a message with the new function name, as suggested by Markus Elfring v4: s/pm_runtime_resume_and_get/pm_runtime_put_noidle/ as noted by John Hovold v3: add the people who signed off on commit dd8088d5a896, expand the log message v2: better keyword scripts/coccinelle/api/pm_runtime_resume_and_get.cocci | 153 +++++++++++++++++ 1 file changed, 153 insertions(+) diff --git a/scripts/coccinelle/api/pm_runtime_resume_and_get.cocci b/scripts/coccinelle/api/pm_runtime_resume_and_get.cocci new file mode 100644 index 000000000000..3387cb606f9b --- /dev/null +++ b/scripts/coccinelle/api/pm_runtime_resume_and_get.cocci @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0-only +/// +/// Use pm_runtime_resume_and_get. +/// pm_runtime_get_sync keeps a reference count on failure, +/// which can lead to leaks. pm_runtime_resume_and_get +/// drops the reference count in the failure case. +/// This rule addresses the cases where the reference count +/// is unlikely to be needed in the failure case. +/// +// Confidence: High +// Copyright: (C) 2021 Julia Lawall, Inria +// URL: https://coccinelle.gitlabpages.inria.fr/website +// Options: --include-headers --no-includes +// Keywords: pm_runtime_get_sync + +virtual patch +virtual context +virtual org +virtual report + +@r0 depends on patch && !context && !org && !report@ +expression ret,e; +@@ + +- ret = pm_runtime_get_sync(e); ++ ret = pm_runtime_resume_and_get(e); +- if (ret < 0) +- pm_runtime_put_noidle(e); + +@r1 depends on patch && !context && !org && !report@ +expression ret,e; +statement S1,S2; +@@ + +- ret = pm_runtime_get_sync(e); ++ ret = pm_runtime_resume_and_get(e); + if (ret < 0) +- { +- pm_runtime_put_noidle(e); + S1 +- } + else S2 + +@r2 depends on patch && !context && !org && !report@ +expression ret,e; +statement S; +@@ + +- ret = pm_runtime_get_sync(e); ++ ret = pm_runtime_resume_and_get(e); + if (ret < 0) { +- pm_runtime_put_noidle(e); + ... + } else S + +@r3 depends on patch && !context && !org && !report@ +expression ret,e; +identifier f; +constant char[] c; +statement S; +@@ + +- ret = pm_runtime_get_sync(e); ++ ret = pm_runtime_resume_and_get(e); + if (ret < 0) +- { + f(...,c,...); +- pm_runtime_put_noidle(e); +- } + else S + +@r4 depends on patch && !context && !org && !report@ +expression ret,e; +identifier f; +constant char[] c; +statement S; +@@ + +- ret = pm_runtime_get_sync(e); ++ ret = pm_runtime_resume_and_get(e); + if (ret < 0) { + f(...,c,...); +- pm_runtime_put_noidle(e); + ... + } else S + +// ---------------------------------------------------------------------------- + +@r2_context depends on !patch && (context || org || report)@ +statement S; +expression e, ret; +position j0, j1; +@@ + +* ret@j0 = pm_runtime_get_sync(e); + if (ret < 0) { +* pm_runtime_put_noidle@j1(e); + ... + } else S + +@r3_context depends on !patch && (context || org || report)@ +identifier f; +statement S; +constant char []c; +expression e, ret; +position j0, j1; +@@ + +* ret@j0 = pm_runtime_get_sync(e); + if (ret < 0) { + f(...,c,...); +* pm_runtime_put_noidle@j1(e); + ... + } else S + +// ---------------------------------------------------------------------------- + +@script:python r2_org depends on org@ +j0 << r2_context.j0; +j1 << r2_context.j1; +@@ + +msg = "WARNING: opportunity for pm_runtime_resume_and_get" +coccilib.org.print_todo(j0[0], msg) +coccilib.org.print_link(j1[0], "") + +@script:python r3_org depends on org@ +j0 << r3_context.j0; +j1 << r3_context.j1; +@@ + +msg = "WARNING: opportunity for pm_runtime_resume_and_get" +coccilib.org.print_todo(j0[0], msg) +coccilib.org.print_link(j1[0], "") + +// ---------------------------------------------------------------------------- + +@script:python r2_report depends on report@ +j0 << r2_context.j0; +j1 << r2_context.j1; +@@ + +msg = "WARNING: opportunity for pm_runtime_resume_and_get on line %s." % (j0[0].line) +coccilib.report.print_report(j0[0], msg) + +@script:python r3_report depends on report@ +j0 << r3_context.j0; +j1 << r3_context.j1; +@@ + +msg = "WARNING: opportunity for pm_runtime_resume_and_get on %s." % (j0[0].line) +coccilib.report.print_report(j0[0], msg) +