Re: [PATCH 3/3] Page Fault Scalability V20: Avoid lock for anonymous write fault

Christoph Lameter
2005-04-29T23:06:59Z

On Fri, 29 Apr 2005, Christoph Hellwig wrote:

> On Fri, Apr 29, 2005 at 12:59:17PM -0700, Christoph Lameter wrote:
> > Do not use the page_table_lock in do_anonymous_page. This will significantly
> > increase the parallelism in the page fault handler for SMP systems. The patch
> > also modifies the definitions of _mm_counter functions so that rss and anon_rss
> > become atomic (and will use atomic64_t if available).
>
> I thought we said all architectures should provide an atomic64_t (and
> given that it's not actually 64bit on 32bit architecture we should
> probably rename it to atomic_long_t)

Yes the way atomic types are provided may need a revision.
First of all we need atomic types that are size bound

atomic8_t
atomic16_t
atomic32_t

and (if available)

atomic64_t

and then some aliases

atomic_t -> atomic type for int
atomic_long_t -> atomic type for long

If these types are available then this patch could be cleaned up to
just use atomic_long_t.