On Thu, 7 Oct 2010 15:24:22 +0900
KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> wrote:
> Greg, I think clear_page_writeback() will not require _any_ locks with this patch.
> But set_page_writeback() requires it...
> (Maybe adding a special function for clear_page_writeback() is better rather than
> adding some complex to switch() in update_page_stat())
>
I'm testing a code like this.
==
/* pc->mem_cgroup is unstable ? */
if (unlikely(mem_cgroup_stealed(mem))) {
/* take a lock against to access pc->mem_cgroup */
if (!in_interrupt()) {
lock_page_cgroup(pc);
need_unlock = true;
mem = pc->mem_cgroup;
if (!mem || !PageCgroupUsed(pc))
goto out;
} else if (idx == MEMCG_NR_FILE_WRITEBACK && (val < 0)) {
/* This is allowed */
} else
BUG();
}
==
Thanks,
-Kame
--
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/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>