On Fri 12-07-13 17:20:09, Li Zefan wrote: [...] > But if I read the code correctly, even no one registers a vmpressure event, > vmpressure() is always running and queue the work item. True but checking there is somebody is rather impractical. First we would have to take a events_lock to check this and then drop it after scheduling the work. Which doesn't guarantee that the registered event wouldn't go away. And even trickier, we would have to do the same for all parents up the hierarchy. -- Michal Hocko SUSE Labs -- 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>