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[v2,0/9] assorted radix fixes and improvemets for page fault and invalidation

Message ID 20180509022022.21226-1-npiggin@gmail.com
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Series assorted radix fixes and improvemets for page fault and invalidation | expand

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Nicholas Piggin May 9, 2018, 2:20 a.m. UTC 
Here's various patches for radix, a few small bugfixes, tracepoint
enablement or partition scope tlbie, and some page fault optimisation.

This was tested with the patch to qemu that enables THP for partition
scope page tables and things seem to work as expected.

Changes since v1:
- Feedback from Paul
  - Improved changelog in the page table umap patch (patch 4).
  - Changed and commented patch 4 to not expect ptes to be unmapped
    in the page fault path, because they should already be invalidated.
    Only unmap and free page tables. This has checks and warnings and
    some recovery code in case ptes are encountered. This is expensive
    compared to the page table unmap, but in my measurements this path
    is pretty rare so I leave it in unconditionally for now to help
    flush out bugs. We can rip it out or put it under a CONFIG easily
    it's just a few lines.

- Fixed PWC flushing with recursive page table freeing (previous code
  would free child page tables before the parent was cleared ad PWC
  flushed, so the MMU may still have been able to reference them).

- That fix to patch 4 required patch 5 as well, so those are squashed
  together. The nature of the code made it pointless to put patch 5
  first.

- Survived some basic stress testing overnight.

Thanks,
Nick

Nicholas Piggin (9):
  KVM: PPC: Book3S HV: radix use correct tlbie sequence in
    kvmppc_radix_tlbie_page
  KVM: PPC: Book3S HV: radix clear pte when unmapping
  KVM: PPC: Book3S HV: use a helper to unmap ptes in the radix fault
    path
  KVM: PPC: Book3S HV: recursively unmap all page table entries when
    unmapping
  powerpc/mm/radix: implement LPID based TLB flushes to be used by KVM
  KVM: PPC: Book3S HV: radix use the Linux translation flush functions
    for partition scope
  KVM: PPC: Book3S HV: radix handle process scoped LPID flush in C, with
    relocation on
  KVM: PPC: Book3S HV: radix refine IO region partition scope attributes
  KVM: PPC: Book3S HV: radix do not clear partition pte when RC or write
    bits do not match

 .../include/asm/book3s/64/tlbflush-radix.h    |   7 +
 arch/powerpc/kvm/book3s_64_mmu_radix.c        | 349 +++++++++++-------
 arch/powerpc/kvm/book3s_hv.c                  |  26 ++
 arch/powerpc/kvm/book3s_hv_rmhandlers.S       |  13 +-
 arch/powerpc/mm/tlb-radix.c                   | 207 +++++++++++
 5 files changed, 467 insertions(+), 135 deletions(-)