Re: Q: behaviour of mlockall(MCL_FUTURE) and VM_GROWSDOWN segments

Andi Kleen (ak@suse.de)
12 Jan 2002 01:33:24 +0100


Andrew Morton <akpm@zip.com.au> writes:

> So in this case, the behaviour I would prefer is MCL_FUTURE for
> all vma's *except* the stack. Stack pages should be locked
> only when they are faulted in. Hard call.

There is just one problem: linuxthread stacks are just ordinary mappings
and they are in no way special to the kernel; they aren't VM_GROWSDOWN.
You would need to add a way to the kernel first to tag the linux thread
stacks in a way that is recognizable to mlockall and then do that
from linuxthreads.

I think for the normal stack - real VM_GROWSDOWN segments - mlockall
already does the right thing.

-Andi
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/