diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/acpica/evmisc.c | 94 |
1 files changed, 55 insertions, 39 deletions
diff --git a/drivers/acpi/acpica/evmisc.c b/drivers/acpi/acpica/evmisc.c index fcaed9fb44ff..8e31bb5a973a 100644 --- a/drivers/acpi/acpica/evmisc.c +++ b/drivers/acpi/acpica/evmisc.c @@ -284,41 +284,41 @@ static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context) * RETURN: ACPI_INTERRUPT_HANDLED * * DESCRIPTION: Invoked directly from the SCI handler when a global lock - * release interrupt occurs. Attempt to acquire the global lock, - * if successful, signal the thread waiting for the lock. + * release interrupt occurs. If there's a thread waiting for + * the global lock, signal it. * * NOTE: Assumes that the semaphore can be signaled from interrupt level. If * this is not possible for some reason, a separate thread will have to be * scheduled to do this. * ******************************************************************************/ +static u8 acpi_ev_global_lock_pending; +static spinlock_t _acpi_ev_global_lock_pending_lock; +#define acpi_ev_global_lock_pending_lock &_acpi_ev_global_lock_pending_lock static u32 acpi_ev_global_lock_handler(void *context) { - u8 acquired = FALSE; + acpi_status status; + acpi_cpu_flags flags; - /* - * Attempt to get the lock. - * - * If we don't get it now, it will be marked pending and we will - * take another interrupt when it becomes free. - */ - ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired); - if (acquired) { + flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock); - /* Got the lock, now wake all threads waiting for it */ + if (!acpi_ev_global_lock_pending) { + goto out; + } - acpi_gbl_global_lock_acquired = TRUE; - /* Send a unit to the semaphore */ + /* Send a unit to the semaphore */ - if (ACPI_FAILURE - (acpi_os_signal_semaphore - (acpi_gbl_global_lock_semaphore, 1))) { - ACPI_ERROR((AE_INFO, - "Could not signal Global Lock semaphore")); - } + status = acpi_os_signal_semaphore(acpi_gbl_global_lock_semaphore, 1); + if (ACPI_FAILURE(status)) { + ACPI_ERROR((AE_INFO, "Could not signal Global Lock semaphore")); } + acpi_ev_global_lock_pending = FALSE; + + out: + acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags); + return (ACPI_INTERRUPT_HANDLED); } @@ -415,6 +415,7 @@ static int acpi_ev_global_lock_acquired; acpi_status acpi_ev_acquire_global_lock(u16 timeout) { + acpi_cpu_flags flags; acpi_status status = AE_OK; u8 acquired = FALSE; @@ -467,32 +468,47 @@ acpi_status acpi_ev_acquire_global_lock(u16 timeout) return_ACPI_STATUS(AE_OK); } - /* Attempt to acquire the actual hardware lock */ + flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock); + + do { + + /* Attempt to acquire the actual hardware lock */ + + ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired); + if (acquired) { + acpi_gbl_global_lock_acquired = TRUE; + + ACPI_DEBUG_PRINT((ACPI_DB_EXEC, + "Acquired hardware Global Lock\n")); + break; + } - ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired); - if (acquired) { + acpi_ev_global_lock_pending = TRUE; - /* We got the lock */ + acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags); + /* + * Did not get the lock. The pending bit was set above, and we + * must wait until we get the global lock released interrupt. + */ ACPI_DEBUG_PRINT((ACPI_DB_EXEC, - "Acquired hardware Global Lock\n")); + "Waiting for hardware Global Lock\n")); - acpi_gbl_global_lock_acquired = TRUE; - return_ACPI_STATUS(AE_OK); - } + /* + * Wait for handshake with the global lock interrupt handler. + * This interface releases the interpreter if we must wait. + */ + status = acpi_ex_system_wait_semaphore( + acpi_gbl_global_lock_semaphore, + ACPI_WAIT_FOREVER); - /* - * Did not get the lock. The pending bit was set above, and we must now - * wait until we get the global lock released interrupt. - */ - ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n")); + flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock); - /* - * Wait for handshake with the global lock interrupt handler. - * This interface releases the interpreter if we must wait. - */ - status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore, - ACPI_WAIT_FOREVER); + } while (ACPI_SUCCESS(status)); + + acpi_ev_global_lock_pending = FALSE; + + acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags); return_ACPI_STATUS(status); } |