From patchwork Mon Jan 24 23:29:35 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rafael Wysocki X-Patchwork-Id: 503491 Received: from smtp1.linux-foundation.org (smtp1.linux-foundation.org [140.211.169.13]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p0ONaCqE023510 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL) for ; Mon, 24 Jan 2011 23:37:00 GMT Received: from daredevil.linux-foundation.org (localhost [127.0.0.1]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p0ONYnFv017367; Mon, 24 Jan 2011 15:34:49 -0800 Received: from ogre.sisk.pl (ogre.sisk.pl [217.79.144.158]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id p0ONXCGm016990 for ; Mon, 24 Jan 2011 15:33:13 -0800 Received: from localhost (localhost.localdomain [127.0.0.1]) by ogre.sisk.pl (Postfix) with ESMTP id DB1671A3218; Tue, 25 Jan 2011 00:35:47 +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 08104-04; Tue, 25 Jan 2011 00:35:10 +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 696A51A315F; Tue, 25 Jan 2011 00:35:09 +0100 (CET) From: "Rafael J. Wysocki" To: Len Brown Date: Tue, 25 Jan 2011 00:29:35 +0100 User-Agent: KMail/1.13.5 (Linux/2.6.38-rc1+; KDE/4.4.4; x86_64; ; ) 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: <201101250029.35999.rjw@sisk.pl> X-Virus-Scanned: amavisd-new at ogre.sisk.pl using MkS_Vir for Linux Received-SPF: pass (localhost is always allowed.) X-Spam-Status: No, hits=-3.939 required=5 tests=AWL, BAYES_00, OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.21 Cc: ACPI Devel Maling List , Linux-pm mailing list , LKML , Jeff Chua Subject: [linux-pm] [PATCH 5/8] ACPI: Make acpi_os_map_memory() avoid creating unnecessary mappings X-BeenThere: linux-pm@lists.linux-foundation.org X-Mailman-Version: 2.1.9 Precedence: list List-Id: Linux power management List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.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 23:37:00 +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 @@ -302,7 +302,7 @@ acpi_map_lookup_virt(void __iomem *virt, void __iomem *__init_refok acpi_os_map_memory(acpi_physical_address phys, acpi_size size) { - struct acpi_ioremap *map, *tmp_map; + struct acpi_ioremap *map; void __iomem *virt; acpi_physical_address pg_off; acpi_size pg_sz; @@ -315,14 +315,25 @@ acpi_os_map_memory(acpi_physical_address if (!acpi_gbl_permanent_mmap) return __acpi_map_table((unsigned long)phys, size); + mutex_lock(&acpi_ioremap_lock); + /* Check if there's a suitable mapping already. */ + map = acpi_map_lookup(phys, size); + if (map) { + kref_get(&map->ref); + goto out; + } + map = kzalloc(sizeof(*map), GFP_KERNEL); - if (!map) + if (!map) { + mutex_unlock(&acpi_ioremap_lock); return NULL; + } pg_off = round_down(phys, PAGE_SIZE); pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; virt = acpi_os_ioremap(pg_off, pg_sz); if (!virt) { + mutex_unlock(&acpi_ioremap_lock); kfree(map); return NULL; } @@ -333,19 +344,10 @@ acpi_os_map_memory(acpi_physical_address map->size = pg_sz; kref_init(&map->ref); - mutex_lock(&acpi_ioremap_lock); - /* Check if page has already been mapped. */ - tmp_map = acpi_map_lookup(phys, size); - if (tmp_map) { - kref_get(&tmp_map->ref); - mutex_unlock(&acpi_ioremap_lock); - iounmap(map->virt); - kfree(map); - return tmp_map->virt + (phys - tmp_map->phys); - } list_add_tail_rcu(&map->list, &acpi_ioremaps); - mutex_unlock(&acpi_ioremap_lock); + out: + mutex_unlock(&acpi_ioremap_lock); return map->virt + (phys - map->phys); } EXPORT_SYMBOL_GPL(acpi_os_map_memory);