diff options
Diffstat (limited to 'arch/i386/kernel/acpi/boot.c')
-rw-r--r-- | arch/i386/kernel/acpi/boot.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/i386/kernel/acpi/boot.c b/arch/i386/kernel/acpi/boot.c index c8f96cff07c6..094300b3a81f 100644 --- a/arch/i386/kernel/acpi/boot.c +++ b/arch/i386/kernel/acpi/boot.c @@ -1327,3 +1327,25 @@ static int __init setup_acpi_sci(char *s) return 0; } early_param("acpi_sci", setup_acpi_sci); + +int __acpi_acquire_global_lock(unsigned int *lock) +{ + unsigned int old, new, val; + do { + old = *lock; + new = (((old & ~0x3) + 2) + ((old >> 1) & 0x1)); + val = cmpxchg(lock, old, new); + } while (unlikely (val != old)); + return (new < 3) ? -1 : 0; +} + +int __acpi_release_global_lock(unsigned int *lock) +{ + unsigned int old, new, val; + do { + old = *lock; + new = old & ~0x3; + val = cmpxchg(lock, old, new); + } while (unlikely (val != old)); + return old & 0x1; +} |