On Mon, Apr 23, 2012 at 05:35:12PM +0900, KAMEZAWA Hiroyuki wrote:
[...]
> > For example, looking into this code flow:
> >
> > -> page_add_file_rmap() (mm/rmap.c)
> > -> mem_cgroup_inc_page_stat(page, MEMCG_NR_FILE_MAPPED) (include/linux/memcontrol.h)
> > -> void mem_cgroup_update_page_stat(page, MEMCG_NR_FILE_MAPPED, 1) (mm/memcontrol.c)
> >
> > And then:
> >
> > void mem_cgroup_update_page_stat(struct page *page,
> > enum mem_cgroup_page_stat_item idx, int val)
> > {
> > ...
> > switch (idx) {
> > case MEMCG_NR_FILE_MAPPED:
> > idx = MEM_CGROUP_STAT_FILE_MAPPED;
> > break;
> > default:
> > BUG();
> > }
> >
> > this_cpu_add(memcg->stat->count[idx], val);
> > ...
> > }
> >
> > So, clearly, this function only bothers updating _FILE_MAPPED only,
> > leaving _CACHE alone.
[...]
>
> NACK.
> CACHE is updated at charge()/uncharge()...inserting/removing page cache to radix-tree.
Interesting; true, we have charge/uncharge in __do_fault()/do_wp_page
and friends. So, we seem to update FILE_MAPPED in the rmap via
cgroup_dec/inc_page_stat, and CACHE is updated via charge/uncharge. Hm.
The code in memory.c is full of if/else ifs, and I wonder if there's
some discrepancy in there, but briefly looking it looks fine. The
code looks correct indeed, but I'm getting the wrong stats. :-/
Thanks,
--
Anton Vorontsov
Email: cbouatmailru@xxxxxxxxx
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>