From patchwork Mon Jan 24 23:30:10 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rafael Wysocki X-Patchwork-Id: 503371 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p0ONY4ZI022023 for ; Mon, 24 Jan 2011 23:34:05 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753335Ab1AXXdX (ORCPT ); Mon, 24 Jan 2011 18:33:23 -0500 Received: from ogre.sisk.pl ([217.79.144.158]:35686 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752856Ab1AXXdV (ORCPT ); Mon, 24 Jan 2011 18:33:21 -0500 Received: from localhost (localhost.localdomain [127.0.0.1]) by ogre.sisk.pl (Postfix) with ESMTP id C837D1A3154; Tue, 25 Jan 2011 00:36:12 +0100 (CET) Received: from ogre.sisk.pl ([127.0.0.1]) by localhost (ogre.sisk.pl [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 07831-08; Tue, 25 Jan 2011 00:35:46 +0100 (CET) Received: from ferrari.rjw.lan (220-bem-13.acn.waw.pl [82.210.184.220]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ogre.sisk.pl (Postfix) with ESMTP id 9234C1A3180; Tue, 25 Jan 2011 00:35:09 +0100 (CET) From: "Rafael J. Wysocki" To: Len Brown Subject: [PATCH 6/8] ACPI: Do not use krefs under a mutex in osl.c Date: Tue, 25 Jan 2011 00:30:10 +0100 User-Agent: KMail/1.13.5 (Linux/2.6.38-rc1+; KDE/4.4.4; x86_64; ; ) Cc: Jeff Chua , LKML , ACPI Devel Maling List , "Linux-pm mailing list" , Matthew Garrett References: <201101201226.41021.rjw@sisk.pl> <201101250025.10817.rjw@sisk.pl> In-Reply-To: <201101250025.10817.rjw@sisk.pl> MIME-Version: 1.0 Message-Id: <201101250030.10678.rjw@sisk.pl> X-Virus-Scanned: amavisd-new at ogre.sisk.pl using MkS_Vir for Linux Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Mon, 24 Jan 2011 23:34:05 +0000 (UTC) Index: linux-2.6/drivers/acpi/osl.c =================================================================== --- linux-2.6.orig/drivers/acpi/osl.c +++ linux-2.6/drivers/acpi/osl.c @@ -105,7 +105,7 @@ struct acpi_ioremap { void __iomem *virt; acpi_physical_address phys; acpi_size size; - struct kref ref; + unsigned long refcount; }; static LIST_HEAD(acpi_ioremaps); @@ -319,7 +319,7 @@ acpi_os_map_memory(acpi_physical_address /* Check if there's a suitable mapping already. */ map = acpi_map_lookup(phys, size); if (map) { - kref_get(&map->ref); + map->refcount++; goto out; } @@ -342,7 +342,7 @@ acpi_os_map_memory(acpi_physical_address map->virt = virt; map->phys = pg_off; map->size = pg_sz; - kref_init(&map->ref); + map->refcount = 1; list_add_tail_rcu(&map->list, &acpi_ioremaps); @@ -352,25 +352,24 @@ acpi_os_map_memory(acpi_physical_address } EXPORT_SYMBOL_GPL(acpi_os_map_memory); -static void acpi_kref_del_iomap(struct kref *ref) +static void acpi_os_drop_map_ref(struct acpi_ioremap *map) { - struct acpi_ioremap *map; - - map = container_of(ref, struct acpi_ioremap, ref); - list_del_rcu(&map->list); + if (!--map->refcount) + list_del_rcu(&map->list); } -static void acpi_os_remove_map(struct acpi_ioremap *map) +static void acpi_os_map_cleanup(struct acpi_ioremap *map) { - synchronize_rcu(); - iounmap(map->virt); - kfree(map); + if (!map->refcount) { + synchronize_rcu(); + iounmap(map->virt); + kfree(map); + } } void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size) { struct acpi_ioremap *map; - int del; if (!acpi_gbl_permanent_mmap) { __acpi_unmap_table(virt, size); @@ -384,11 +383,10 @@ void __ref acpi_os_unmap_memory(void __i WARN(true, PREFIX "%s: bad address %p\n", __func__, virt); return; } - del = kref_put(&map->ref, acpi_kref_del_iomap); + acpi_os_drop_map_ref(map); mutex_unlock(&acpi_ioremap_lock); - if (del) - acpi_os_remove_map(map); + acpi_os_map_cleanup(map); } EXPORT_SYMBOL_GPL(acpi_os_unmap_memory); @@ -418,7 +416,6 @@ static int acpi_os_map_generic_address(s static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) { struct acpi_ioremap *map; - int del; if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) return; @@ -432,11 +429,10 @@ static void acpi_os_unmap_generic_addres mutex_unlock(&acpi_ioremap_lock); return; } - del = kref_put(&map->ref, acpi_kref_del_iomap); + acpi_os_drop_map_ref(map); mutex_unlock(&acpi_ioremap_lock); - if (del) - acpi_os_remove_map(map); + acpi_os_map_cleanup(map); } #ifdef ACPI_FUTURE_USAGE