Messages in this thread |  | | Date | Wed, 4 Oct 2000 17:34:55 -0300 (BRST) | From | Rik van Riel <> | Subject | Re: Weightless process class |
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On Wed, 4 Oct 2000, Nathan Paul Simons wrote: > On Wed, Oct 04, 2000 at 04:16:22PM -0300, Rik van Riel wrote: > > Do we have something like an in_kernel(proc) macro ??? > > "user_mode()" in include/asm/ptrace.h? But that only checks to > see if the regs struct you passed it are from a kernel thread or > not. No checks to see if the process has any kernel locks.
A process can't grab a kernel lock and then switch back to user mode, can it? (if it could, I can imagine some nasty DoS attacks...)
Problem is, when we decide to schedule in a process or not, we know the process was last stuck in schedule() ... in kernel mode ;(
I'd love to be proven wrong though ... this would be some extremely useful functionality ;)
regards,
Rik -- "What you're running that piece of shit Gnome?!?!" -- Miguel de Icaza, UKUUG 2000
http://www.conectiva.com/ http://www.surriel.com/
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