Re: [PATCH v3 00/14] Implement use of HW assistance on TLB table walk on 8xx

[Christophe LEROY]

Hi

Please note that I'm currently deeply reworking this serie in order to 
make it more clear hence more simple to review. So don't consider taking 
it yet (except maybe the first patch of the serie which is a bugfix).

Christophe

Le 29/05/2018 Ã 17:50, Christophe Leroy a ÃcritÂ:
> The purpose of this serie is to implement hardware assistance for TLB table walk
> on the 8xx.
>
> First part is to make L1 entries and L2 entries independant.
> For that, we need to alter ioremap functions in order to handle GUARD attribute
> at the PGD/PMD level.
>
> Last part is to reuse PTE fragment implemented on PPC64 in order to
> not waste 16k Pages for page tables as only 4k are used.
>
> Tested successfully on 8xx.
>
> Successfull compilation on following defconfigs (v3):
> ppc64_defconfig
> ppc64e_defconfig
>
> Successfull compilation on following defconfigs (v2):
> ppc64_defconfig
> ppc64e_defconfig
> pseries_defconfig
> pmac32_defconfig
> linkstation_defconfig
> corenet32_smp_defconfig
> ppc40x_defconfig
> storcenter_defconfig
> ppc44x_defconfig
>
> Changes in v3:
>   - Fixed an issue in the 09/14 when CONFIG_PIN_TLB_TEXT was not enabled
>   - Added performance measurement in the 09/14 commit log
>   - Rebased on latest 'powerpc/merge' tree, which conflicted with 13/14
>
> Changes in v2:
>   - Removed the 3 first patchs which have been applied already
>   - Fixed compilation errors reported by Michael
>   - Squashed the commonalisation of ioremap functions into a single patch
>   - Fixed the use of pte_fragment
>   - Added a patch optimising perf counting of TLB misses and instructions
>
> Christophe Leroy (14):
>    Revert "powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for
>      CONFIG_SWAP"
>    powerpc: move io mapping functions into ioremap.c
>    powerpc: make ioremap_bot common to PPC32 and PPC64
>    powerpc: common ioremap functions.
>    powerpc: use _ALIGN_DOWN macro for VMALLOC_BASE
>    powerpc/nohash32: allow setting GUARDED attribute in the PMD directly
>    powerpc/8xx: set GUARDED attribute in the PMD directly
>    powerpc/8xx: Remove PTE_ATOMIC_UPDATES
>    powerpc/mm: Use hardware assistance in TLB handlers on the 8xx
>    powerpc/8xx: reunify TLB handler routines
>    powerpc/8xx: Free up SPRN_SPRG_SCRATCH2
>    powerpc/mm: Make pte_fragment_alloc() common to PPC32 and PPC64
>    powerpc/mm: Use pte_fragment_alloc() on 8xx
>    powerpc/8xx: Move SW perf counters in first 32kb of memory
>
>   arch/powerpc/include/asm/book3s/32/pgtable.h |  29 +-
>   arch/powerpc/include/asm/book3s/64/pgtable.h |   2 +
>   arch/powerpc/include/asm/highmem.h           |  11 -
>   arch/powerpc/include/asm/hugetlb.h           |   4 +-
>   arch/powerpc/include/asm/machdep.h           |   2 +-
>   arch/powerpc/include/asm/mmu-8xx.h           |  38 +--
>   arch/powerpc/include/asm/mmu_context.h       |  53 ++++
>   arch/powerpc/include/asm/nohash/32/pgalloc.h |  56 +++-
>   arch/powerpc/include/asm/nohash/32/pgtable.h |  77 +++--
>   arch/powerpc/include/asm/nohash/32/pte-8xx.h |   6 +-
>   arch/powerpc/include/asm/nohash/pgtable.h    |   4 +
>   arch/powerpc/include/asm/page.h              |   2 +-
>   arch/powerpc/include/asm/pgtable-types.h     |   4 +
>   arch/powerpc/kernel/head_8xx.S               | 409 +++++++++++----------------
>   arch/powerpc/mm/8xx_mmu.c                    |  12 +-
>   arch/powerpc/mm/Makefile                     |   2 +-
>   arch/powerpc/mm/dma-noncoherent.c            |   2 +-
>   arch/powerpc/mm/dump_linuxpagetables.c       |  32 ++-
>   arch/powerpc/mm/hugetlbpage.c                |  12 +
>   arch/powerpc/mm/init_32.c                    |   6 +-
>   arch/powerpc/mm/{pgtable_64.c => ioremap.c}  | 239 ++++++----------
>   arch/powerpc/mm/mem.c                        |  16 +-
>   arch/powerpc/mm/mmu_context_book3s64.c       |  44 ---
>   arch/powerpc/mm/mmu_context_nohash.c         |   4 +
>   arch/powerpc/mm/pgtable-book3s64.c           |  72 -----
>   arch/powerpc/mm/pgtable.c                    |  82 ++++++
>   arch/powerpc/mm/pgtable_32.c                 | 167 +++--------
>   arch/powerpc/mm/pgtable_64.c                 | 177 ------------
>   arch/powerpc/platforms/Kconfig.cputype       |  19 ++
>   29 files changed, 657 insertions(+), 926 deletions(-)
>   copy arch/powerpc/mm/{pgtable_64.c => ioremap.c} (53%)