acpi_status
acpi_ex_acquire_mutex_object(u16 timeout,
union acpi_operand_object *obj_desc,
acpi_thread_id thread_id)
{
acpi_status status;
ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex_object, obj_desc);
if (!obj_desc) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Support for multiple acquires by the owning thread */
if (obj_desc->mutex.thread_id == thread_id) {
/*
* The mutex is already owned by this thread, just increment the
* acquisition depth
*/
obj_desc->mutex.acquisition_depth++;
return_ACPI_STATUS(AE_OK);
}
/* Acquire the mutex, wait if necessary. Special case for Global Lock */
if (obj_desc == acpi_gbl_global_lock_mutex) {
status = acpi_ev_acquire_global_lock(timeout);
} else {
status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
timeout);
}
if (ACPI_FAILURE(status)) {
/* Includes failure from a timeout on time_desc */
return_ACPI_STATUS(status);
}
/* Acquired the mutex: update mutex object */
obj_desc->mutex.thread_id = thread_id;
obj_desc->mutex.acquisition_depth = 1;
obj_desc->mutex.original_sync_level = 0;
obj_desc->mutex.owner_thread = NULL; /* Used only for AML Acquire() */
return_ACPI_STATUS(AE_OK);
}
acpi_status
acpi_ex_system_acquire_mutex(union acpi_operand_object * time_desc,
union acpi_operand_object * obj_desc)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_PTR(ex_system_acquire_mutex, obj_desc);
if (!obj_desc) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Support for the _GL_ Mutex object -- go get the global lock */
if (obj_desc->mutex.os_mutex == ACPI_GLOBAL_LOCK) {
status =
acpi_ev_acquire_global_lock((u16) time_desc->integer.value);
return_ACPI_STATUS(status);
}
status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
(u16) time_desc->integer.value);
return_ACPI_STATUS(status);
}
acpi_status
acpi_ds_begin_method_execution(struct acpi_namespace_node *method_node,
union acpi_operand_object *obj_desc,
struct acpi_walk_state *walk_state)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE_PTR(ds_begin_method_execution, method_node);
if (!method_node) {
return_ACPI_STATUS(AE_NULL_ENTRY);
}
/* Prevent wraparound of thread count */
if (obj_desc->method.thread_count == ACPI_UINT8_MAX) {
ACPI_ERROR((AE_INFO,
"Method reached maximum reentrancy limit (255)"));
return_ACPI_STATUS(AE_AML_METHOD_LIMIT);
}
/*
* If this method is serialized, we need to acquire the method mutex.
*/
if (obj_desc->method.method_flags & AML_METHOD_SERIALIZED) {
/*
* Create a mutex for the method if it is defined to be Serialized
* and a mutex has not already been created. We defer the mutex creation
* until a method is actually executed, to minimize the object count
*/
if (!obj_desc->method.mutex) {
status = acpi_ds_create_method_mutex(obj_desc);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
/*
* The current_sync_level (per-thread) must be less than or equal to
* the sync level of the method. This mechanism provides some
* deadlock prevention
*
* Top-level method invocation has no walk state at this point
*/
if (walk_state &&
(walk_state->thread->current_sync_level >
obj_desc->method.mutex->mutex.sync_level)) {
ACPI_ERROR((AE_INFO,
"Cannot acquire Mutex for method [%4.4s], current SyncLevel is too large (%d)",
acpi_ut_get_node_name(method_node),
walk_state->thread->current_sync_level));
return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
}
/*
* Obtain the method mutex if necessary. Do not acquire mutex for a
* recursive call.
*/
if (acpi_os_get_thread_id() !=
obj_desc->method.mutex->mutex.owner_thread_id) {
/*
* Acquire the method mutex. This releases the interpreter if we
* block (and reacquires it before it returns)
*/
status =
acpi_ex_system_wait_mutex(obj_desc->method.mutex->
mutex.os_mutex,
ACPI_WAIT_FOREVER);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Update the mutex and walk info and save the original sync_level */
obj_desc->method.mutex->mutex.owner_thread_id =
acpi_os_get_thread_id();
if (walk_state) {
obj_desc->method.mutex->mutex.
original_sync_level =
walk_state->thread->current_sync_level;
walk_state->thread->current_sync_level =
obj_desc->method.sync_level;
} else {
obj_desc->method.mutex->mutex.
original_sync_level =
obj_desc->method.mutex->mutex.sync_level;
}
}
/* Always increase acquisition depth */
obj_desc->method.mutex->mutex.acquisition_depth++;
}
/*
* Allocate an Owner ID for this method, only if this is the first thread
* to begin concurrent execution. We only need one owner_id, even if the
* method is invoked recursively.
*/
if (!obj_desc->method.owner_id) {
status = acpi_ut_allocate_owner_id(&obj_desc->method.owner_id);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
}
/*
* Increment the method parse tree thread count since it has been
* reentered one more time (even if it is the same thread)
*/
obj_desc->method.thread_count++;
return_ACPI_STATUS(status);
cleanup:
/* On error, must release the method mutex (if present) */
if (obj_desc->method.mutex) {
acpi_os_release_mutex(obj_desc->method.mutex->mutex.os_mutex);
}
return_ACPI_STATUS(status);
}
acpi_status acpi_ev_acquire_global_lock(u16 timeout)
{
acpi_cpu_flags flags;
acpi_status status;
u8 acquired = FALSE;
ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
/*
* Only one thread can acquire the GL at a time, the global_lock_mutex
* enforces this. This interface releases the interpreter if we must wait.
*/
status =
acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex->mutex.
os_mutex, timeout);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Update the global lock handle and check for wraparound. The handle is
* only used for the external global lock interfaces, but it is updated
* here to properly handle the case where a single thread may acquire the
* lock via both the AML and the acpi_acquire_global_lock interfaces. The
* handle is therefore updated on the first acquire from a given thread
* regardless of where the acquisition request originated.
*/
acpi_gbl_global_lock_handle++;
if (acpi_gbl_global_lock_handle == 0) {
acpi_gbl_global_lock_handle = 1;
}
/*
* Make sure that a global lock actually exists. If not, just
* treat the lock as a standard mutex.
*/
if (!acpi_gbl_global_lock_present) {
acpi_gbl_global_lock_acquired = TRUE;
return_ACPI_STATUS(AE_OK);
}
flags = acpi_os_acquire_lock(acpi_gbl_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;
}
/*
* Did not get the lock. The pending bit was set above, and
* we must now wait until we receive the global lock
* released interrupt.
*/
acpi_gbl_global_lock_pending = TRUE;
acpi_os_release_lock(acpi_gbl_global_lock_pending_lock, flags);
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"Waiting for hardware Global Lock\n"));
/*
* 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);
flags = acpi_os_acquire_lock(acpi_gbl_global_lock_pending_lock);
} while (ACPI_SUCCESS(status));
acpi_gbl_global_lock_pending = FALSE;
acpi_os_release_lock(acpi_gbl_global_lock_pending_lock, flags);
return_ACPI_STATUS(status);
}
acpi_status
acpi_ex_acquire_mutex(union acpi_operand_object *time_desc,
union acpi_operand_object *obj_desc,
struct acpi_walk_state *walk_state)
{
acpi_status status;
ACPI_FUNCTION_TRACE_PTR(ex_acquire_mutex, obj_desc);
if (!obj_desc) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Sanity check: we must have a valid thread ID */
if (!walk_state->thread) {
ACPI_ERROR((AE_INFO,
"Cannot acquire Mutex [%4.4s], null thread info",
acpi_ut_get_node_name(obj_desc->mutex.node)));
return_ACPI_STATUS(AE_AML_INTERNAL);
}
/*
* Current Sync must be less than or equal to the sync level of the
* mutex. This mechanism provides some deadlock prevention
*/
if (walk_state->thread->current_sync_level > obj_desc->mutex.sync_level) {
ACPI_ERROR((AE_INFO,
"Cannot acquire Mutex [%4.4s], current SyncLevel is too large (%d)",
acpi_ut_get_node_name(obj_desc->mutex.node),
walk_state->thread->current_sync_level));
return_ACPI_STATUS(AE_AML_MUTEX_ORDER);
}
/* Support for multiple acquires by the owning thread */
if (obj_desc->mutex.owner_thread_id == acpi_os_get_thread_id()) {
/*
* The mutex is already owned by this thread, just increment the
* acquisition depth
*/
obj_desc->mutex.acquisition_depth++;
return_ACPI_STATUS(AE_OK);
}
/* Acquire the mutex, wait if necessary. Special case for Global Lock */
if (obj_desc->mutex.os_mutex == acpi_gbl_global_lock_mutex) {
status =
acpi_ev_acquire_global_lock((u16) time_desc->integer.value);
} else {
status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
(u16) time_desc->integer.
value);
}
if (ACPI_FAILURE(status)) {
/* Includes failure from a timeout on time_desc */
return_ACPI_STATUS(status);
}
/* Have the mutex: update mutex and walk info and save the sync_level */
obj_desc->mutex.owner_thread_id = acpi_os_get_thread_id();
obj_desc->mutex.acquisition_depth = 1;
obj_desc->mutex.original_sync_level =
walk_state->thread->current_sync_level;
walk_state->thread->current_sync_level = obj_desc->mutex.sync_level;
/* Link the mutex to the current thread for force-unlock at method exit */
acpi_ex_link_mutex(obj_desc, walk_state->thread);
return_ACPI_STATUS(AE_OK);
}
acpi_status acpi_ev_acquire_global_lock(u16 timeout)
{
acpi_status status = AE_OK;
u8 acquired = FALSE;
ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
/*
* Only one thread can acquire the GL at a time, the global_lock_mutex
* enforces this. This interface releases the interpreter if we must wait.
*/
status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
if (status == AE_TIME) {
if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
acpi_ev_global_lock_acquired++;
return AE_OK;
}
}
if (ACPI_FAILURE(status)) {
status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
}
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
acpi_ev_global_lock_acquired++;
/*
* Make sure that a global lock actually exists. If not, just treat
* the lock as a standard mutex.
*/
if (!acpi_gbl_global_lock_present) {
acpi_gbl_global_lock_acquired = TRUE;
return_ACPI_STATUS(AE_OK);
}
/* Attempt to acquire the actual hardware lock */
ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
if (acquired) {
/* We got the lock */
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"Acquired hardware Global Lock\n"));
acpi_gbl_global_lock_acquired = TRUE;
return_ACPI_STATUS(AE_OK);
}
/*
* 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"));
/*
* 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);
return_ACPI_STATUS(status);
}