Hi, this is the thrid version of the patchset previously sent [1]. I have basically only rebased it on top of next-20160428 tree and dropped "crypto: get rid of superfluous __GFP_REPEAT" which went through crypto tree. I have added two more md patches as I couldn't resist more alloc related cleanups at that area. Motivation: While working on something unrelated I've checked the current usage of __GFP_REPEAT in the tree. It seems that a majority of the usage is and always has been bogus because __GFP_REPEAT has always been about costly high order allocations while we are using it for order-0 or very small orders very often. It seems that a big pile of them is just a copy&paste when a code has been adopted from one arch to another. I think it makes some sense to get rid of them because they are just making the semantic more unclear. Please note that GFP_REPEAT is documented as * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt * _might_ fail. This depends upon the particular VM implementation. while !costly requests have basically nofail semantic. So one could reasonably expect that order-0 request with __GFP_REPEAT will not loop for ever. This is not implemented right now though. I would like to move on with __GFP_REPEAT and define a better semantic for it. One thought was to rename it to __GFP_BEST_EFFORT which would behave consistently for all orders and guarantee that the allocation would try as long as it seem feasible or fail eventually. !costly request would then finally get a request context which neiter fails too early (GFP_NORETRY) nor endlessly loops in the allocator for ever (default behavior). Costly high order requests would keep the current semantic. We have discussed that at LSF/MM this year and another suggestion was to introduce __GFP_TRYHARD instead which would be implicit for all orders and users would opt out by ~__GFP_TRYHARD instead. I am not sure which way is better right now but I plan to do the clean up first before going further with semantic changes. $ git grep __GFP_REPEAT next/master | wc -l 109 $ git grep __GFP_REPEAT | wc -l 35 So we are down to the third after this patch series. The remaining places really seem to be relying on __GFP_REPEAT due to large allocation requests. This still needs some double checking which I will do later after all the simple ones are sorted out. I am touching a lot of arch specific code here and I hope I got it right but as a matter of fact I even didn't compile test for some archs as I do not have cross compiler for them. Patches should be quite trivial to review for stupid compile mistakes though. The tricky parts are usually hidden by macro definitions and thats where I would appreciate help from arch maintainers. [1] http://lkml.kernel.org/r/1460372892-8157-1-git-send-email-mhocko@xxxxxxxxxx -- 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>