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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 1B71CC7618F for ; Tue, 16 Jul 2019 18:41:30 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7A60221743 for ; Tue, 16 Jul 2019 18:41:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A60221743 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-16481-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 13804 invoked by uid 550); 16 Jul 2019 18:41:24 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 13783 invoked from network); 16 Jul 2019 18:41:23 -0000 Date: Tue, 16 Jul 2019 11:40:25 -0700 From: "Paul E. McKenney" To: "Joel Fernandes (Google)" Cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Alexey Kuznetsov , Bjorn Helgaas , Borislav Petkov , c0d1n61at3@gmail.com, "David S. Miller" , edumazet@google.com, Hideaki YOSHIFUJI , "H. Peter Anvin" , Ingo Molnar , Jonathan Corbet , Josh Triplett , keescook@chromium.org, kernel-hardening@lists.openwall.com, kernel-team@android.com, Lai Jiangshan , Len Brown , linux-acpi@vger.kernel.org, linux-doc@vger.kernel.org, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Mathieu Desnoyers , neilb@suse.com, netdev@vger.kernel.org, Oleg Nesterov , Pavel Machek , peterz@infradead.org, "Rafael J. Wysocki" , Rasmus Villemoes , rcu@vger.kernel.org, Steven Rostedt , Tejun Heo , Thomas Gleixner , will@kernel.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" Subject: Re: [PATCH 5/9] driver/core: Convert to use built-in RCU list checking (v1) Message-ID: <20190716184025.GG14271@linux.ibm.com> References: <20190715143705.117908-1-joel@joelfernandes.org> <20190715143705.117908-6-joel@joelfernandes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190715143705.117908-6-joel@joelfernandes.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-07-16_04:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound 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-1907160228 On Mon, Jul 15, 2019 at 10:37:01AM -0400, Joel Fernandes (Google) wrote: > list_for_each_entry_rcu has built-in RCU and lock checking. Make use of > it in driver core. > > Acked-by: Greg Kroah-Hartman > Signed-off-by: Joel Fernandes (Google) This one looks ready. Thanx, Paul > --- > drivers/base/base.h | 1 + > drivers/base/core.c | 10 ++++++++++ > drivers/base/power/runtime.c | 15 ++++++++++----- > 3 files changed, 21 insertions(+), 5 deletions(-) > > diff --git a/drivers/base/base.h b/drivers/base/base.h > index b405436ee28e..0d32544b6f91 100644 > --- a/drivers/base/base.h > +++ b/drivers/base/base.h > @@ -165,6 +165,7 @@ static inline int devtmpfs_init(void) { return 0; } > /* Device links support */ > extern int device_links_read_lock(void); > extern void device_links_read_unlock(int idx); > +extern int device_links_read_lock_held(void); > extern int device_links_check_suppliers(struct device *dev); > extern void device_links_driver_bound(struct device *dev); > extern void device_links_driver_cleanup(struct device *dev); > diff --git a/drivers/base/core.c b/drivers/base/core.c > index da84a73f2ba6..85e82f38717f 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -68,6 +68,11 @@ void device_links_read_unlock(int idx) > { > srcu_read_unlock(&device_links_srcu, idx); > } > + > +int device_links_read_lock_held(void) > +{ > + return srcu_read_lock_held(&device_links_srcu); > +} > #else /* !CONFIG_SRCU */ > static DECLARE_RWSEM(device_links_lock); > > @@ -91,6 +96,11 @@ void device_links_read_unlock(int not_used) > { > up_read(&device_links_lock); > } > + > +int device_links_read_lock_held(void) > +{ > + return lock_is_held(&device_links_lock); > +} > #endif /* !CONFIG_SRCU */ > > /** > diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c > index 952a1e7057c7..7a10e8379a70 100644 > --- a/drivers/base/power/runtime.c > +++ b/drivers/base/power/runtime.c > @@ -287,7 +287,8 @@ static int rpm_get_suppliers(struct device *dev) > { > struct device_link *link; > > - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { > + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, > + device_links_read_lock_held()) { > int retval; > > if (!(link->flags & DL_FLAG_PM_RUNTIME) || > @@ -309,7 +310,8 @@ static void rpm_put_suppliers(struct device *dev) > { > struct device_link *link; > > - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { > + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, > + device_links_read_lock_held()) { > if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND) > continue; > > @@ -1640,7 +1642,8 @@ void pm_runtime_clean_up_links(struct device *dev) > > idx = device_links_read_lock(); > > - list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { > + list_for_each_entry_rcu(link, &dev->links.consumers, s_node, > + device_links_read_lock_held()) { > if (link->flags & DL_FLAG_STATELESS) > continue; > > @@ -1662,7 +1665,8 @@ void pm_runtime_get_suppliers(struct device *dev) > > idx = device_links_read_lock(); > > - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) > + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, > + device_links_read_lock_held()) > if (link->flags & DL_FLAG_PM_RUNTIME) { > link->supplier_preactivated = true; > refcount_inc(&link->rpm_active); > @@ -1683,7 +1687,8 @@ void pm_runtime_put_suppliers(struct device *dev) > > idx = device_links_read_lock(); > > - list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) > + list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, > + device_links_read_lock_held()) > if (link->supplier_preactivated) { > link->supplier_preactivated = false; > if (refcount_dec_not_one(&link->rpm_active)) > -- > 2.22.0.510.g264f2c817a-goog >