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acpi_status acpi_os_execute(acpi_execute_type type,			    acpi_osd_exec_callback function, void *context)这个函数主要作用是执行形参的callback函数，根据type的不同可以选择不同的queue来执行acpi_status acpi_os_execute(acpi_execute_type type,			    acpi_osd_exec_callback function, void *context){	acpi_status status = AE_OK;	struct acpi_os_dpc *dpc;	struct workqueue_struct *queue;	int ret;	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,			  "Scheduling function [%p(%p)] for deferred execution.\n",			  function, context));	#一般用于debug	if (type == OSL_DEBUGGER_MAIN_THREAD) {		ret = acpi_debugger_create_thread(function, context);		if (ret) {			pr_err("Call to kthread_create() failed.\n");			status = AE_ERROR;		}		goto out_thread;	}	/*	 * Allocate/initialize DPC structure.  Note that this memory will be	 * freed by the callee.  The kernel handles the work_struct list  in a	 * way that allows us to also free its memory inside the callee.	 * Because we may want to schedule several tasks with different	 * parameters we can't use the approach some kernel code uses of	 * having a static work_struct.	 */	#申请一个acpi_os_dpc 结构，用于保存要执行的callback和参数	dpc = kzalloc(sizeof(struct acpi_os_dpc), GFP_ATOMIC);	if (!dpc)		return AE_NO_MEMORY;	dpc->function = function;	dpc->context = context;	/*	 * To prevent lockdep from complaining unnecessarily, make sure that	 * there is a different static lockdep key for each workqueue by using	 * INIT_WORK() for each of them separately.	 */	 #根据不同的type，可以选择不同的queue 来执行	if (type == OSL_NOTIFY_HANDLER) {	#根据type给queue赋值，并初始化要执行的队列		queue = kacpi_notify_wq;		INIT_WORK(&dpc->work, acpi_os_execute_deferred);	} else if (type == OSL_GPE_HANDLER) {		queue = kacpid_wq;		INIT_WORK(&dpc->work, acpi_os_execute_deferred);	} else {		pr_err("Unsupported os_execute type %d.\n", type);		status = AE_ERROR;	}	if (ACPI_FAILURE(status))		goto err_workqueue;	/*	 * On some machines, a software-initiated SMI causes corruption unless	 * the SMI runs on CPU 0.  An SMI can be initiated by any AML, but	 * typically it's done in GPE-related methods that are run via	 * workqueues, so we can avoid the known corruption cases by always	 * queueing on CPU 0.	 */	 #执行这个queue	ret = queue_work_on(0, queue, &dpc->work);	if (!ret) {		printk(KERN_ERR PREFIX			  "Call to queue_work() failed.\n");		status = AE_ERROR;	}err_workqueue:	if (ACPI_FAILURE(status))		kfree(dpc);out_thread:	return status;}

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