On Fri, 23 Mar 2012 09:18:46 +0900 KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote: > >> +#ifdef CONFIG_SWAP > >> + /* > >> + * Avoid lookup_swap_cache() not to update statistics. > >> + */ > > > > I don't understand this comment - what is it trying to tell us? > > > > > High Dickins advised me to use find_get_page() rather than lookup_swap_cache() > because lookup_swap_cache() has some statistics with swap. ah. --- a/mm/memcontrol.c~memcg-change-behavior-of-moving-charges-at-task-move-fix +++ a/mm/memcontrol.c @@ -5137,7 +5137,8 @@ static struct page *mc_handle_swap_pte(s return NULL; #ifdef CONFIG_SWAP /* - * Avoid lookup_swap_cache() not to update statistics. + * Use find_get_page() rather than lookup_swap_cache() because the + * latter alters statistics. */ page = find_get_page(&swapper_space, ent.val); #endif > >> + page = find_get_page(&swapper_space, ent.val); > > > > The code won't even compile if CONFIG_SWAP=n? > > > > mm/built-in.o: In function `mc_handle_swap_pte': > /home/kamezawa/Kernel/next/linux/mm/memcontrol.c:5172: undefined reference to `swapper_space' > make: *** [.tmp_vmlinux1] Error 1 > > Ah...but I think this function (mc_handle_swap_pte) itself should be under CONFIG_SWAP. > I'll post v2. Confused. The new reference to swapper_space is already inside #ifdef CONFIG_SWAP. -- 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>