String to be used for the name of the process. This string will be copied into the p_comm member of the new process struct proc.
The main function for this kernel process to run.
A pointer to a struct proc pointer that should be updated to point to the newly created process process structure. If this variable is NULL, then it is ignored.
The kthread_create function is used to create a kernel thread. The new thread shares its address space with process 0, the swapper process, and runs in kernel mode only. The func argument specifies the function that the thread should execute. The arg argument is an arbitrary pointer that is passed in as the only argument to func when it is called by the new process. The newpp pointer points to a struct proc pointer that is to be updated to point to the newly created process. If this argument is NULL, then it is ignored. The flags argument specifies a set of flags as described in rfork(2). The pages argument specifies the size of the new kernel threads stack in pages. If 0 is used, the default kernel stack size is allocated. The rest of the arguments form a printf(9) argument list that is used to build the name of the new thread and is stored in the p_comm member of the new threads struct proc.
The kthread_exit function is used to terminate kernel threads. It should be called by the main function of the kernel thread rather than letting the main function return to its caller. The ecode argument specifies the exit status of the thread. While exiting, the function exit1(9) will initiate a call to wakeup(9) on the thread handle.
The kthread_resume, kthread_suspend, and kthread_suspend_check functions are used to suspend and resume a kernel thread. During the main loop of its execution, a kernel thread that wishes to allow itself to be suspended should call kthread_suspend_check passing in curproc as the only argument. This function checks to see if the kernel thread has been asked to suspend. If it has, it will tsleep(9) until it is told to resume. Once it has been told to resume it will return allowing execution of the kernel thread to continue. The other two functions are used to notify a kernel thread of a suspend or resume request. The p argument points to the struct proc of the kernel thread to suspend or resume. For kthread_suspend, the timo argument specifies a timeout to wait for the kernel thread to acknowledge the suspend request and suspend itself.
The kproc_shutdown function is meant to be registered as a shutdown event for kernel threads that need to be suspended voluntarily during system shutdown so as not to interfere with system shutdown activities. The actual suspension of the kernel thread is done with kthread_suspend.