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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,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 9B3C9C43441 for ; Sun, 11 Nov 2018 19:47:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 580AF20872 for ; Sun, 11 Nov 2018 19:47:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 580AF20872 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729789AbeKLFhT (ORCPT ); Mon, 12 Nov 2018 00:37:19 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:55236 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727026AbeKLFdq (ORCPT ); Mon, 12 Nov 2018 00:33:46 -0500 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wABJi9OF121669 for ; Sun, 11 Nov 2018 14:44:20 -0500 Received: from e11.ny.us.ibm.com (e11.ny.us.ibm.com [129.33.205.201]) by mx0a-001b2d01.pphosted.com with ESMTP id 2npdcu1hyn-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Sun, 11 Nov 2018 14:44:19 -0500 Received: from localhost by e11.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sun, 11 Nov 2018 19:44:18 -0000 Received: from b01cxnp23034.gho.pok.ibm.com (9.57.198.29) by e11.ny.us.ibm.com (146.89.104.198) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Sun, 11 Nov 2018 19:44:14 -0000 Received: from b01ledav003.gho.pok.ibm.com (b01ledav003.gho.pok.ibm.com [9.57.199.108]) by b01cxnp23034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wABJiD4w22544546 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sun, 11 Nov 2018 19:44:13 GMT Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 45F01B2065; Sun, 11 Nov 2018 19:44:13 +0000 (GMT) Received: from b01ledav003.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 230A1B2068; Sun, 11 Nov 2018 19:44:13 +0000 (GMT) Received: from paulmck-ThinkPad-W541 (unknown [9.85.207.24]) by b01ledav003.gho.pok.ibm.com (Postfix) with ESMTP; Sun, 11 Nov 2018 19:44:13 +0000 (GMT) Received: by paulmck-ThinkPad-W541 (Postfix, from userid 1000) id 0107216C5D59; Sun, 11 Nov 2018 11:44:12 -0800 (PST) From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org, "Paul E. McKenney" , Jessica Yu Subject: [PATCH tip/core/rcu 24/41] modules: Replace synchronize_sched() and call_rcu_sched() Date: Sun, 11 Nov 2018 11:43:53 -0800 X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181111194104.GA4787@linux.ibm.com> References: <20181111194104.GA4787@linux.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18111119-2213-0000-0000-00000315A7E5 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010028; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000270; SDB=6.01116019; UDB=6.00578733; IPR=6.00896120; MB=3.00024114; MTD=3.00000008; XFM=3.00000015; UTC=2018-11-11 19:44:18 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18111119-2214-0000-0000-00005C386BBC Message-Id: <20181111194410.6368-24-paulmck@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-11-11_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=618 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1811110188 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that synchronize_rcu() waits for preempt-disable regions of code as well as RCU read-side critical sections, synchronize_sched() can be replaced by synchronize_rcu(). Similarly, call_rcu_sched() can be replaced by call_rcu(). This commit therefore makes these changes. Signed-off-by: Paul E. McKenney Cc: Jessica Yu --- kernel/module.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index 49a405891587..99b46c32d579 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2159,7 +2159,7 @@ static void free_module(struct module *mod) /* Remove this module from bug list, this uses list_del_rcu */ module_bug_cleanup(mod); /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */ - synchronize_sched(); + synchronize_rcu(); mutex_unlock(&module_mutex); /* This may be empty, but that's OK */ @@ -3507,15 +3507,15 @@ static noinline int do_init_module(struct module *mod) /* * We want to free module_init, but be aware that kallsyms may be * walking this with preempt disabled. In all the failure paths, we - * call synchronize_sched(), but we don't want to slow down the success + * call synchronize_rcu(), but we don't want to slow down the success * path, so use actual RCU here. * Note that module_alloc() on most architectures creates W+X page * mappings which won't be cleaned up until do_free_init() runs. Any * code such as mark_rodata_ro() which depends on those mappings to * be cleaned up needs to sync with the queued work - ie - * rcu_barrier_sched() + * rcu_barrier() */ - call_rcu_sched(&freeinit->rcu, do_free_init); + call_rcu(&freeinit->rcu, do_free_init); mutex_unlock(&module_mutex); wake_up_all(&module_wq); @@ -3526,7 +3526,7 @@ static noinline int do_init_module(struct module *mod) fail: /* Try to protect us from buggy refcounters. */ mod->state = MODULE_STATE_GOING; - synchronize_sched(); + synchronize_rcu(); module_put(mod); blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); @@ -3819,7 +3819,7 @@ static int load_module(struct load_info *info, const char __user *uargs, ddebug_cleanup: ftrace_release_mod(mod); dynamic_debug_remove(mod, info->debug); - synchronize_sched(); + synchronize_rcu(); kfree(mod->args); free_arch_cleanup: module_arch_cleanup(mod); @@ -3834,7 +3834,7 @@ static int load_module(struct load_info *info, const char __user *uargs, mod_tree_remove(mod); wake_up_all(&module_wq); /* Wait for RCU-sched synchronizing before releasing mod->list. */ - synchronize_sched(); + synchronize_rcu(); mutex_unlock(&module_mutex); free_module: /* Free lock-classes; relies on the preceding sync_rcu() */ -- 2.17.1