Re: [PATCH] mm: remove global locks from mm/highmem.c

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, 29 Jan 2007 17:31:20 -0800
"Martin J. Bligh" <[email protected]> wrote:

> Peter Zijlstra wrote:
> > On Sun, 2007-01-28 at 14:29 -0800, Andrew Morton wrote:
> > 
> >> As Christoph says, it's very much preferred that code be migrated over to
> >> kmap_atomic().  Partly because kmap() is deadlockable in situations where a
> >> large number of threads are trying to take two kmaps at the same time and
> >> we run out.  This happened in the past, but incidences have gone away,
> >> probably because of kmap->kmap_atomic conversions.
> > 
> >> From which callsite have you measured problems?
> > 
> > CONFIG_HIGHPTE code in -rt was horrid. I'll do some measurements on
> > mainline.
> > 
> 
> CONFIG_HIGHPTE is always horrid -we've known that for years.

We have?  What's wrong with it?  <looks around for bug reports>

> Don't use it.
> 
> If that's all we're fixing here, I'd be highly suspect ...

highpte uses atomic kmaps - it is unrelated to this work.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux