diff options
| author | Myron Stowe <myron.stowe@hp.com> | 2010-10-21 22:24:09 +0200 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2010-10-25 05:28:16 +0200 |
| commit | 78cdb3ed4053798c894899b15d2255fb880edad4 (patch) | |
| tree | 351af153f725e4641d10c8ccccf7a2c53896f87d /drivers/acpi/osl.c | |
| parent | ACPI: Pre-map 'system event' related register blocks (diff) | |
| download | linux-78cdb3ed4053798c894899b15d2255fb880edad4.tar.xz linux-78cdb3ed4053798c894899b15d2255fb880edad4.zip | |
ACPI: Convert simple locking to RCU based locking
Convert the simple locking introduced earlier for the ACPI MMIO
remappings list to an RCU based locking scheme.
Signed-off-by: Myron Stowe <myron.stowe@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/osl.c')
| -rw-r--r-- | drivers/acpi/osl.c | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index c63d4cb37dab..32826893c2e6 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; |