Re: [PATCH] percpu updates

[Andrew Morton <akpm@zip.com.au>]

Brian Gerst wrote:
> 
> These patches convert some of the existing arrays based on NR_CPUS to
> use the new per cpu code.
> 
> ...
> -extern struct page_state {
> +struct page_state {
>         unsigned long nr_dirty;
>         unsigned long nr_locked;
>         unsigned long nr_pagecache;
> -} ____cacheline_aligned_in_smp page_states[NR_CPUS];
> +};
> +
> +extern struct page_state __per_cpu_data page_states;

When I did this a couple of weeks back it failed in
mysterious ways and I ended up parking it.  Failure
symptoms included negative numbers being reported in
/proc/meminfo for "Locked" and "Dirty".

How well has this been tested?  (If the answer
is "not very" then please wait until I've tested
it out...)

-