On Tue, 16 Feb 2010, Nick Piggin wrote: > > As I already explained when you first brought this up, the possibility of > > not invoking the oom killer is not unique to GFP_DMA, it is also possible > > for GFP_NOFS. Since __GFP_NOFAIL is deprecated and there are no current > > users of GFP_DMA | __GFP_NOFAIL, that warning is completely unnecessary. > > We're not adding any additional __GFP_NOFAIL allocations. > > Completely agree with this request. Actually, I think even better you > should just add && !(gfp_mask & __GFP_NOFAIL). Deprecated doesn't mean > it is OK to break the API (callers *will* oops or corrupt memory if > __GFP_NOFAIL returns NULL). > ... unless it's used with GFP_ATOMIC, which we've always returned NULL for when even ALLOC_HARDER can't find pages, right? I'm wondering where this strong argument in favor of continuing to support __GFP_NOFAIL was when I insisted we call the oom killer for them even for allocations over PAGE_ALLOC_COSTLY_ORDER when __alloc_pages_nodemask() was refactored back in 2.6.31. The argument was that nobody is allocating that high of orders of __GFP_NOFAIL pages so we don't need to free memory for them and that's where the deprecation of the modifier happened in the first place. Ultimately, we did invoke the oom killer for those allocations because there's no chance of forward progress otherwise and, unlike __GFP_DMA, GFP_KERNEL | __GFP_NOFAIL actually is popular. I'll add this check to __alloc_pages_may_oom() for the !(gfp_mask & __GFP_NOFAIL) path since we're all content with endlessly looping. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>