On Fri 08-05-20 14:31:06, Johannes Weiner wrote: > The previous patches have simplified the access rules around > page->mem_cgroup somewhat: > > 1. We never change page->mem_cgroup while the page is isolated by > somebody else. This was by far the biggest exception to our rules > and it didn't stop at lock_page() or lock_page_memcg(). > > 2. We charge pages before they get put into page tables now, so the > somewhat fishy rule about "can be in page table as long as it's > still locked" is now gone and boiled down to having an exclusive > reference to the page. > > Document the new rules. Any of the following will stabilize the > page->mem_cgroup association: > > - the page lock > - LRU isolation > - lock_page_memcg() > - exclusive access to the page > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> > Reviewed-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx> > Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Thanks a lot this is a big improvement and simplification. I have gone through the whole series finally. I have followed up where necessary but overall this is really nice! Sorry I couldn't jump in to review in time. -- Michal Hocko SUSE Labs
