On 11/30/2012 07:52 PM, Tejun Heo wrote: > Hey, Glauber. > > I don't know enough about memcg to be acking this but overall it looks > pretty good to me. > > On Fri, Nov 30, 2012 at 05:31:22PM +0400, Glauber Costa wrote: >> For the problem of attaching tasks, I am using something similar to cpusets: >> when task attaching starts, we will flip a flag "attach_in_progress", that will >> be flipped down when it finishes. This way, all readers can know that a task is >> joining the group and take action accordingly. With this, we can guarantee that >> the behavior of move_charge_at_immigrate continues safe > > Yeap, attach_in_progress is useful if there are some conditions which > shouldn't change between ->can_attach() and ->attach(). With the > immigrate thing gone, this no longer is necessary, right? > Yes and no. While it can help with immigrate, we still have kmem that needs to be protected against tasks joining. However, kmem is easier. If attach_in_progress is ever positive, it means that a task is joining, and it is already unacceptable for kmem - so we can fail right away. -- 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/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>