On Thu, 3 Feb 2011 15:12:30 +0100 Johannes Weiner <hannes@xxxxxxxxxxx> wrote: > The page_cgroup array is set up before even fork is initialized. I > seriously doubt that this code executes before the array is alloc'd. > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> I don't have solid answer to this. If some module use radix-tree and enter pages to it, mem_cgroup may see it. But.. For my opinion, tring this is good. Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> > --- > mm/memcontrol.c | 5 +---- > 1 files changed, 1 insertions(+), 4 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index a145c9e..6abaa10 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -2343,10 +2343,7 @@ static int mem_cgroup_charge_common(struct page *page, struct mm_struct *mm, > } > > pc = lookup_page_cgroup(page); > - /* can happen at boot */ > - if (unlikely(!pc)) > - return 0; > - prefetchw(pc); > + BUG_ON(!pc); /* XXX: remove this and move pc lookup into commit */ > > ret = __mem_cgroup_try_charge(mm, gfp_mask, &mem, oom, page_size); > if (ret || !mem) > -- > 1.7.4 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx 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>