From patchwork Thu Oct 21 20:24:09 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Myron Stowe X-Patchwork-Id: 272141 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 o9LKO6k9005766 for ; Thu, 21 Oct 2010 20:24:11 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756650Ab0JUUYL (ORCPT ); Thu, 21 Oct 2010 16:24:11 -0400 Received: from g1t0026.austin.hp.com ([15.216.28.33]:24596 "EHLO g1t0026.austin.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755287Ab0JUUYK (ORCPT ); Thu, 21 Oct 2010 16:24:10 -0400 Received: from g1t0038.austin.hp.com (g1t0038.austin.hp.com [16.236.32.44]) by g1t0026.austin.hp.com (Postfix) with ESMTP id 1264DC94A; Thu, 21 Oct 2010 20:24:10 +0000 (UTC) Received: from ldl (ldl.usa.hp.com [16.125.112.222]) by g1t0038.austin.hp.com (Postfix) with ESMTP id D70403000B; Thu, 21 Oct 2010 20:24:09 +0000 (UTC) Received: from localhost (ldl.fc.hp.com [127.0.0.1]) by ldl (Postfix) with ESMTP id C6588CF0022; Thu, 21 Oct 2010 14:24:09 -0600 (MDT) Received: from ldl ([127.0.0.1]) by localhost (ldl.fc.hp.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id M1HKRWYq7Ouz; Thu, 21 Oct 2010 14:24:09 -0600 (MDT) Received: from eh.fc.hp.com (bob.lnx.usa.hp.com [16.125.112.218]) by ldl (Postfix) with ESMTP id B1ADACF0020; Thu, 21 Oct 2010 14:24:09 -0600 (MDT) Received: from bob.kio (localhost [127.0.0.1]) by eh.fc.hp.com (Postfix) with ESMTP id 97A3626151; Thu, 21 Oct 2010 14:24:09 -0600 (MDT) Subject: [PATCH 5/7] ACPI: Convert simple locking to RCU based locking To: lenb@kernel.org From: Myron Stowe Cc: linux-acpi@vger.kernel.org, ak@linux.intel.com, ying.huang@intel.com Date: Thu, 21 Oct 2010 14:24:09 -0600 Message-ID: <20101021202409.9220.84703.stgit@bob.kio> In-Reply-To: <20101021201916.9220.5711.stgit@bob.kio> References: <20101021201916.9220.5711.stgit@bob.kio> User-Agent: StGit/0.15 MIME-Version: 1.0 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-4.2.3 (demeter1.kernel.org [140.211.167.41]); Thu, 21 Oct 2010 20:24:11 +0000 (UTC) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index c63d4cb..3282689 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -244,13 +244,13 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) } } -/* Must be called with 'acpi_ioremap_lock' lock held. */ +/* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */ static void __iomem * acpi_map_vaddr_lookup(acpi_physical_address phys, acpi_size size) { struct acpi_ioremap *map; - list_for_each_entry(map, &acpi_ioremaps, list) + list_for_each_entry_rcu(map, &acpi_ioremaps, list) if (map->phys <= phys && phys + size <= map->phys + map->size) return map->virt + (phys - map->phys); @@ -258,13 +258,13 @@ acpi_map_vaddr_lookup(acpi_physical_address phys, acpi_size size) return NULL; } -/* Must be called with 'acpi_ioremap_lock' lock held. */ +/* Must be called with 'acpi_ioremap_lock' or RCU read lock held. */ static struct acpi_ioremap * acpi_map_lookup_virt(void __iomem *virt, acpi_size size) { struct acpi_ioremap *map; - list_for_each_entry(map, &acpi_ioremaps, list) + list_for_each_entry_rcu(map, &acpi_ioremaps, list) if (map->virt == virt && map->size == size) return map; @@ -302,7 +302,7 @@ acpi_os_map_memory(acpi_physical_address phys, acpi_size size) map->size = size; spin_lock_irqsave(&acpi_ioremap_lock, flags); - list_add_tail(&map->list, &acpi_ioremaps); + list_add_tail_rcu(&map->list, &acpi_ioremaps); spin_unlock_irqrestore(&acpi_ioremap_lock, flags); return virt; @@ -328,9 +328,10 @@ void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size) return; } - list_del(&map->list); + list_del_rcu(&map->list); spin_unlock_irqrestore(&acpi_ioremap_lock, flags); + synchronize_rcu(); iounmap(map->virt); kfree(map); } @@ -584,11 +585,10 @@ acpi_os_read_memory(acpi_physical_address phys_addr, u32 * value, u32 width) u32 dummy; void __iomem *virt_addr; int size = width / 8, unmap = 0; - unsigned long flags; - spin_lock_irqsave(&acpi_ioremap_lock, flags); + rcu_read_lock(); virt_addr = acpi_map_vaddr_lookup(phys_addr, size); - spin_unlock_irqrestore(&acpi_ioremap_lock, flags); + rcu_read_unlock(); if (!virt_addr) { virt_addr = ioremap(phys_addr, size); unmap = 1; @@ -621,11 +621,10 @@ acpi_os_write_memory(acpi_physical_address phys_addr, u32 value, u32 width) { void __iomem *virt_addr; int size = width / 8, unmap = 0; - unsigned long flags; - spin_lock_irqsave(&acpi_ioremap_lock, flags); + rcu_read_lock(); virt_addr = acpi_map_vaddr_lookup(phys_addr, size); - spin_unlock_irqrestore(&acpi_ioremap_lock, flags); + rcu_read_unlock(); if (!virt_addr) { virt_addr = ioremap(phys_addr, size); unmap = 1;