On Mon, Aug 31, 2015 at 10:46:04AM -0400, Tejun Heo wrote: > Hello, Vladimir. > > On Mon, Aug 31, 2015 at 05:20:49PM +0300, Vladimir Davydov wrote: > ... > > That being said, this is the fix at the right layer. > > While this *might* be a necessary workaround for the hard limit case > right now, this is by no means the fix at the right layer. The > expectation is that mm keeps a reasonable amount of memory available > for allocations which can't block. These allocations may fail from > time to time depending on luck and under extreme memory pressure but > the caller should be able to depend on it as a speculative allocation > mechanism which doesn't fail willy-nilly. > > Hardlimit breaking GFP_NOWAIT behavior is a bug on memcg side, not > slab or slub. I never denied that there is GFP_NOWAIT/GFP_NOFS problem in memcg. I even proposed ways to cope with it in one of the previous e-mails. Nevertheless, we just can't allow slab/slub internals call memcg_charge whenever they want as I pointed out in a parallel thread. Thanks, Vladimir -- 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>