Michal Hocko wrote: > On Fri 24-11-17 22:21:55, Tetsuo Handa wrote: > > Michal Hocko wrote: > > > > Since we can encourage register_shrinker() callers to check for failure > > > > by marking register_shrinker() as __must_check, unregister_shrinker() > > > > can stay silent. > > > > > > I am not sure __must_check is the right way. We already do get > > > allocation warning if the registration fails so silent unregister is > > > acceptable. Unchecked register_shrinker is a bug like any other > > > unchecked error path. > > > > I consider that __must_check is the simplest way to find all of > > unchecked register_shrinker bugs. Why not to encourage users to fix? > > because git grep doesn't require to patch the kernel and still provide > the information you want. I can't interpret this line. How git grep relevant? If all register_shrinker() users were careful enough to check for git history everytime, we would not have come to current code. It is duty of patch author to take necessary precautions (for in-tree code) when some API starts to return an error which previously did not return an error. In this case, it is duty of author of commit 1d3d4437eae1bb29 ("vmscan: per-node deferred work"). > I would understand __must_check if we had > hundreds users of this api and they come and go quickly. -- 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>