On Fri, 23 Apr 2010 22:57:06 +0200 Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > On Fri, 2010-04-23 at 13:17 -0700, Greg Thelen wrote: > > +static void mem_cgroup_begin_page_cgroup_reassignment(void) > > +{ > > + VM_BUG_ON(mem_cgroup_account_move_ongoing); > > + mem_cgroup_account_move_ongoing = true; > > + synchronize_rcu(); > > +} > > btw, you know synchronize_rcu() is _really_ slow? > IIUC, this is called once per an event when task is moved and we have to move accouting information...and once per an event when we call rmdir() to destroy cgroup. So, this is not frequenctly called. (hooks to migration in this patch is removable.) 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>