lkml.org 
[lkml]   [1999]   [Jan]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: MM deadlock [was: Re: arca-vm-8...]


On Sun, 24 Jan 1999, Alan Cox wrote:
>
> Being able to throw out page tables is something that is going to be needed
> too. As far as I can see that does not mean complexity. The Linux VM is
> very clean in its page handling, there is almost nothing in the page tables
> that cannot be flushed or dumped to disk if need be.

There _is_ a major problem: being able to swap out page tables means that
the thing that swaps them out _has_ to own the mm semaphore.

That's the right thing to do anyway, but it means, for example, that the
_only_ process that can page stuff out would be kswapd.

Who knows? Maybe I should just bite the bullet and make that the rule,
then we could forget about all the extra recursive semaphore crap too. And
it has other advantages - it can speed up the page fault handler (which
right now has to get the kernel lock for certain situations).

Once that is done, paging out page tables is not really a problem.

> There are real cases where grab large linear block is needed.

Nobody has so far shown a reasonable implementation where this would be
possible.

Linus


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

\
 
 \ /
  Last update: 2005-03-22 13:49    [W:0.162 / U:0.064 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site