acpi_status acpi_ex_acquire_mutex ( acpi_operand_object *time_desc, acpi_operand_object *obj_desc, acpi_walk_state *walk_state) { acpi_status status; FUNCTION_TRACE_PTR ("Ex_acquire_mutex", obj_desc); if (!obj_desc) { return_ACPI_STATUS (AE_BAD_PARAMETER); } /* * Current Sync must be less than or equal to the sync level of the * mutex. This mechanism provides some deadlock prevention */ if (walk_state->current_sync_level > obj_desc->mutex.sync_level) { return_ACPI_STATUS (AE_AML_MUTEX_ORDER); } /* * If the mutex is already owned by this thread, * just increment the acquisition depth */ if (obj_desc->mutex.owner == walk_state) { obj_desc->mutex.acquisition_depth++; return_ACPI_STATUS (AE_OK); } /* Acquire the mutex, wait if necessary */ status = acpi_ex_system_acquire_mutex (time_desc, obj_desc); if (ACPI_FAILURE (status)) { /* Includes failure from a timeout on Time_desc */ return_ACPI_STATUS (status); } /* Have the mutex, update mutex and walk info */ obj_desc->mutex.owner = walk_state; obj_desc->mutex.acquisition_depth = 1; walk_state->current_sync_level = obj_desc->mutex.sync_level; /* Link the mutex to the walk state for force-unlock at method exit */ acpi_ex_link_mutex (obj_desc, (acpi_operand_object *) &(walk_state->walk_list->acquired_mutex_list)); return_ACPI_STATUS (AE_OK); }
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) { /* Special case for Global Lock, allow all threads */ if ((obj_desc->mutex.owner_thread->thread_id == walk_state->thread->thread_id) || (obj_desc->mutex.os_mutex == ACPI_GLOBAL_LOCK)) { /* * 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 */ status = acpi_ex_system_acquire_mutex(time_desc, obj_desc); 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 = walk_state->thread; 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); }