From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752079AbbCLA7p (ORCPT ); Wed, 11 Mar 2015 20:59:45 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:65438 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751158AbbCLA7Q (ORCPT ); Wed, 11 Mar 2015 20:59:16 -0400 From: "Rafael J. Wysocki" To: Linux Kernel Mailing List Cc: Bjorn Helgaas , ACPI Devel Maling List Subject: [RFC][PATCH 1/2] PNP: Convert pnp_lock into a mutex Date: Thu, 12 Mar 2015 02:21:04 +0100 Message-ID: <1575158.va5ogmMc59@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.19.0+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <2163789.xYALhKGkH0@vostro.rjw.lan> References: <2163789.xYALhKGkH0@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki pnp_lock is a spinlock, but it is only acquired from process context, so it may be a mutex just fine and that will allow a couple of problems to be avoided going forward. Signed-off-by: Rafael J. Wysocki --- drivers/pnp/base.h | 2 +- drivers/pnp/card.c | 25 +++++++++++++------------ drivers/pnp/core.c | 19 ++++++++++--------- 3 files changed, 24 insertions(+), 22 deletions(-) Index: linux-pm/drivers/pnp/core.c =================================================================== --- linux-pm.orig/drivers/pnp/core.c +++ linux-pm/drivers/pnp/core.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -19,7 +20,7 @@ static LIST_HEAD(pnp_protocols); LIST_HEAD(pnp_global); -DEFINE_SPINLOCK(pnp_lock); +DEFINE_MUTEX(pnp_lock); /* * ACPI or PNPBIOS should tell us about all platform devices, so we can @@ -55,7 +56,7 @@ int pnp_register_protocol(struct pnp_pro INIT_LIST_HEAD(&protocol->devices); INIT_LIST_HEAD(&protocol->cards); nodenum = 0; - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); /* assign the lowest unused number */ list_for_each(pos, &pnp_protocols) { @@ -67,7 +68,7 @@ int pnp_register_protocol(struct pnp_pro } list_add_tail(&protocol->protocol_list, &pnp_protocols); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); protocol->number = nodenum; dev_set_name(&protocol->dev, "pnp%d", nodenum); @@ -80,9 +81,9 @@ int pnp_register_protocol(struct pnp_pro */ void pnp_unregister_protocol(struct pnp_protocol *protocol) { - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_del(&protocol->protocol_list); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); device_unregister(&protocol->dev); } @@ -161,10 +162,10 @@ int __pnp_add_device(struct pnp_dev *dev { pnp_fixup_device(dev); dev->status = PNP_READY; - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_add_tail(&dev->global_list, &pnp_global); list_add_tail(&dev->protocol_list, &dev->protocol->devices); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); if (dev->protocol->can_wakeup) device_set_wakeup_capable(&dev->dev, dev->protocol->can_wakeup(dev)); @@ -203,10 +204,10 @@ int pnp_add_device(struct pnp_dev *dev) void __pnp_remove_device(struct pnp_dev *dev) { - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_del(&dev->global_list); list_del(&dev->protocol_list); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); device_unregister(&dev->dev); } Index: linux-pm/drivers/pnp/base.h =================================================================== --- linux-pm.orig/drivers/pnp/base.h +++ linux-pm/drivers/pnp/base.h @@ -3,7 +3,7 @@ * Bjorn Helgaas */ -extern spinlock_t pnp_lock; +extern struct mutex pnp_lock; extern const struct attribute_group *pnp_dev_groups[]; void *pnp_alloc(long size); Index: linux-pm/drivers/pnp/card.c =================================================================== --- linux-pm.orig/drivers/pnp/card.c +++ linux-pm/drivers/pnp/card.c @@ -5,6 +5,7 @@ */ #include +#include #include #include #include @@ -244,10 +245,10 @@ int pnp_add_card(struct pnp_card *card) } pnp_interface_attach_card(card); - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_add_tail(&card->global_list, &pnp_cards); list_add_tail(&card->protocol_list, &card->protocol->cards); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); /* we wait until now to add devices in order to ensure the drivers * will be able to use all of the related devices on the card @@ -276,10 +277,10 @@ void pnp_remove_card(struct pnp_card *ca struct list_head *pos, *temp; device_unregister(&card->dev); - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_del(&card->global_list); list_del(&card->protocol_list); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); list_for_each_safe(pos, temp, &card->devices) { struct pnp_dev *dev = card_to_pnp_dev(pos); pnp_remove_card_device(dev); @@ -297,10 +298,10 @@ int pnp_add_card_device(struct pnp_card dev->card_link = NULL; dev_set_name(&dev->dev, "%02x:%02x.%02x", dev->protocol->number, card->number, dev->number); - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); dev->card = card; list_add_tail(&dev->card_list, &card->devices); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); return 0; } @@ -310,10 +311,10 @@ int pnp_add_card_device(struct pnp_card */ void pnp_remove_card_device(struct pnp_dev *dev) { - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); dev->card = NULL; list_del(&dev->card_list); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); __pnp_remove_device(dev); } @@ -426,9 +427,9 @@ int pnp_register_card_driver(struct pnp_ if (error < 0) return error; - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_add_tail(&drv->global_list, &pnp_card_drivers); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); list_for_each_safe(pos, temp, &pnp_cards) { struct pnp_card *card = @@ -444,9 +445,9 @@ int pnp_register_card_driver(struct pnp_ */ void pnp_unregister_card_driver(struct pnp_card_driver *drv) { - spin_lock(&pnp_lock); + mutex_lock(&pnp_lock); list_del(&drv->global_list); - spin_unlock(&pnp_lock); + mutex_unlock(&pnp_lock); pnp_unregister_driver(&drv->link); }