kernel_isrthread(9r)													      kernel_isrthread(9r)

NAME

       kernel_isrthread - General: Starts a fixed priority kernel thread dedicated to interrupt service

SYNOPSIS

       thread_t kernel_isrthread(
	       task_t task,
	       void (*start) (void),
	       int pri );

ARGUMENTS

       Specifies  a  pointer to a task structure.  This pointer identifies the task in which the kernel_isrthread routine starts the newly created
       kernel thread dedicated to interrupt service handling.  Specifies a pointer to an routine that is the entry point  for  the  newly  created
       kernel  thread.	 Specifies the scheduling priority level for the newly created kernel thread. See the DESCRIPTION section for the priority
       usage table that describes the possible scheduling priorities.

DESCRIPTION

       The kernel_isrthread routine creates and starts a kernel thread at the specified entry point. This kernel  thread  handles  only  interrupt
       service	requests  in  the  specified task and at the specified priority level. A kernel module should always attach a kernel thread to the
       ``first task.''

       The following priority usage table describes the possible scheduling priorities. The first column shows a range of priorities.  The  second
       column  shows  an  associated scheduling priority constant defined in <src/kernel/kern/sched.h> (if applicable). The third column describes
       the usage of the priority ranges. To specify a scheduling priority of 38, you pass the constant BASEPRI_SYSTEM.	To  specify  a	scheduling
       priority of 33, you can pass the following: BASEPRI_HIGHEST + 1.

       --------------------------------------------------------------
       Priority   Constant		     Usage
       --------------------------------------------------------------
       0--31	  N/A			     Realtime kernel threads
       32--38	  BASEPRI_HIGHEST	--   Operating system kernel
		  BASEPRI_SYSTEM	     threads
       44--64	  BASEPRI_USER		--   User kernel threads
		  BASEPRI_LOWEST
       --------------------------------------------------------------

RETURN VALUES

       Upon successful completion, kernel_isrthread returns a pointer to the thread structure associated with the kernel  thread  started  at  the
       specified entry point. Kernel modules can use this pointer as a handle to a specific kernel thread in calls to other kernel threads-related
       routines.

SEE ALSO

       Routines: kernel_thread_w_arg(9r)

       Data Structures: task(9s), thread(9s)

															      kernel_isrthread(9r)