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author | Rafael J. Wysocki <rjw@sisk.pl> | 2011-02-09 01:37:53 +0300 |
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committer | Rafael J. Wysocki <rjw@sisk.pl> | 2011-02-24 21:58:41 +0300 |
commit | 7fe135dc058faea0ce319a03e3b6f98c5049955c (patch) | |
tree | ecd7f70c02bb15ff36749f9db4d8c9d14af4f623 /drivers/acpi/osl.c | |
parent | 7bbb890358b96cb6f77adc6815f2072bdf813d5d (diff) | |
download | linux-7fe135dc058faea0ce319a03e3b6f98c5049955c.tar.xz |
ACPI: Avoid walking the list of memory mappings in osl.c twice in a row
Make acpi_os_unmap_generic_address() use acpi_map_lookup() to find
the desired iomap and drop the reference to it directly (and
eventually remove it if necessary) instead of calling
acpi_os_unmap_memory(), which requires us to walk the list of ACPI
iomaps twice in a row (first, to get the virtual address associated
with the iomap and second, to get the iomap itself).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'drivers/acpi/osl.c')
-rw-r--r-- | drivers/acpi/osl.c | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 97061928249a..f6785bced215 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -358,6 +358,13 @@ static void acpi_kref_del_iomap(struct kref *ref) list_del_rcu(&map->list); } +static void acpi_os_remove_map(struct acpi_ioremap *map) +{ + synchronize_rcu(); + iounmap(map->virt); + kfree(map); +} + void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size) { struct acpi_ioremap *map; @@ -372,20 +379,14 @@ void __ref acpi_os_unmap_memory(void __iomem *virt, acpi_size size) map = acpi_map_lookup_virt(virt, size); if (!map) { mutex_unlock(&acpi_ioremap_lock); - printk(KERN_ERR PREFIX "%s: bad address %p\n", __func__, virt); - dump_stack(); + WARN(true, PREFIX "%s: bad address %p\n", __func__, virt); return; } - del = kref_put(&map->ref, acpi_kref_del_iomap); mutex_unlock(&acpi_ioremap_lock); - if (!del) - return; - - synchronize_rcu(); - iounmap(map->virt); - kfree(map); + if (del) + acpi_os_remove_map(map); } EXPORT_SYMBOL_GPL(acpi_os_unmap_memory); @@ -414,8 +415,8 @@ static int acpi_os_map_generic_address(struct acpi_generic_address *addr) static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) { - void __iomem *virt; - acpi_size size = addr->bit_width / 8; + struct acpi_ioremap *map; + int del; if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) return; @@ -424,10 +425,16 @@ static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr) return; mutex_lock(&acpi_ioremap_lock); - virt = acpi_map_vaddr_lookup(addr->address, size); + map = acpi_map_lookup(addr->address, addr->bit_width / 8); + if (!map) { + mutex_unlock(&acpi_ioremap_lock); + return; + } + del = kref_put(&map->ref, acpi_kref_del_iomap); mutex_unlock(&acpi_ioremap_lock); - acpi_os_unmap_memory(virt, size); + if (del) + acpi_os_remove_map(map); } #ifdef ACPI_FUTURE_USAGE |