Messages in this thread | | | Date | Wed, 4 Nov 2020 19:11:00 +0000 | From | Christoph Hellwig <> | Subject | Re: [PATCH v5 05/15] mm/frame-vector: Use FOLL_LONGTERM |
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On Wed, Nov 04, 2020 at 03:02:14PM -0400, Jason Gunthorpe wrote: > I saw that once and I really couldn't make sense of it.. > What use is having futex's that only work on THP pages? Confused > > CH said there was no case of HAVE_FAST_GUP !ARCH_HAS_PTE_SPECIAL, is > one hidden someplace then?
ARCH_HAS_PTE_SPECIAL is selected by:
arc arm (if LPAE) arm64 mips (if !(32BIT && CPU_HAS_RIXI)) powerpc riscv s390 sh sparc (if SPARC64) x86
HAVE_FAST_GUP is supported by:
arm (if LPAE) arm64 mips powerpc s390 sh x86
so mips would be a candidate. But I think only in theory, as the options selecting CPU_HAS_RIXI do not select CPU_SUPPORTS_HUGEPAGES. Adding the mips maintainer to double check my logic.
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