On Thu, 17 Nov 2011, Andrew Morton wrote: > > So, just remove the dummy and dangerous definitions since they are no > > longer needed and reveals the correct dependencies. Tested on > > architectures using the definitions with allyesconfig: x86 (even with > > thp), hppa, mips, powerpc, s390, sh3, sh4, sparc, and sparc64, and > > with defconfig on ia64. > > How could arch/mips/mm/tlb-r4k.c:local_flush_tlb_range() compile OK > with this change? > This was tested on Linus' tree, not on Ralf's linux-next tree. All uses of HPAGE_* are protected by CONFIG_HUGETLB_PAGE as it appropriately should be in Linus' tree in that file. > What that function is doing looks reasonable to me. Why fill the poor > thing with an ifdef mess? > > otoh, catching mistakes is good too. Doing it at runtime as David > proposes is OK. > Nobody else needs it other than Ralf's pending change, and you're suggesting we need them in a generic header file when any sane arch that uses hugepages (all of them, in the current tree) declares these themselves in arch/*/include/asm/page.h where it's supposed to be done? Why on earth do we have CONFIG_HUGETLB_PAGE for at all, then? To catch code that's operating on hugepages when our kernel doesn't support it. I'd much rather break the build than get a runtime BUG() because we want to avoid an #ifdef or actually write well-written code like every other arch has! Panicking the code to find errors like this is just insanity.
