System processes recognition.

[John Baldwin]

On Tuesday 15 March 2005 07:51 am, Pawel Jakub Dawidek wrote:
> Hi.
>
> I found, that there is no way to know if the given process is a system
> (kernel) process or not:
>
> - P_SYSTEM flag is used also for userland processes (init),
> - P_KTHREAD flag is not used for swapper,
> - ps(1) thinks, that it found system process when there are no arguments
>   (argv == NULL || argv[0] == NULL), but this is not true:
> 	char *argv[1] = { NULL };
>
> 	execve("/path/to/somewhere", argv, NULL);
>   /path/to/somewhere process will be recognized by ps(1) as a system
> process.
>
> The easiest way to fix it, is to add P_KTHREAD flag to the swapper, I
> think:
>
> --- init_main.c	17 Feb 2005 10:00:09 -0000	1.255
> +++ init_main.c	15 Mar 2005 12:48:04 -0000
> @@ -365,7 +365,7 @@ proc0_init(void *dummy __unused)
>  	session0.s_leader = p;
>
>  	p->p_sysent = &null_sysvec;
> -	p->p_flag = P_SYSTEM;
> +	p->p_flag = P_SYSTEM | P_KTHREAD;
>  	p->p_sflag = PS_INMEM;
>  	p->p_state = PRS_NORMAL;
>  	knlist_init(&p->p_klist, &p->p_mtx);
>
> Opinions?

I think this is ok.  Ask bde@, he might say that P_SYSTEM should be removed 
from init.  (Can't remember if he is in favor of that or not.)

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org