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copy_page improvements

Andrew Pinski linux-arm-kernel 1 version New

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  1. v1 Latest0 of 4 patches 0 repliesNew

Patches in v1 No applies recorded yet

None of the 4 patches the cover letter announces are in this archive.

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PatchAndrew Pinski
SeriesT-b

Trailers given in replies are filled; those carried in the patches from earlier versions are outlined with dashes.

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Cover letter [PATCH 0/4] copy_page improvements
Quoted 9 lines · Will Deacon

Hi all,

This patch series aims to improve our copy_page implementation on both CPUs with and without hardware prefetchers. It is inspired by a previous patch series from Andrew, and one of the patches is lifted directly from there:

   http://lists.infradead.org/pipermail/linux-arm-kernel/2016-January/399132.html
Quoted 8 lines

Changes from that series:

* Applies on top of mainline
* Inverted the capability to the more generic ARM64_HAS_NO_HW_PREFETCH
* Re-jigged the MIDR detection to try to keep it simple

I've left copy_template alone for now, since the template really deals with 64 bytes per iteration, which would need changing.

Right, I had looked at doing that also for newlib/glibc but the code is too complex.

Quoted 3 lines

Andrew -- it would be helpful if you could take this for a spin on ThunderX to make sure it didn't screw anything up.

Yes it works and I get the needed prefetch in copy_page.

Tested-by Andrew Pinski <[email protected]>

Thanks,
Andrew

Quoted 23 lines

Cheers,

Will

--->8

Andrew Pinski (1):
arm64: lib: patch in prfm for copy_page if requested

Will Deacon (3):
arm64: prefetch: don't provide spin_lock_prefetch with LSE
arm64: prefetch: add alternative pattern for CPUs without a prefetcher
arm64: lib: improve copy_page to deal with 128 bytes at a time

  arch/arm64/include/asm/cpufeature.h |  3 +-
  arch/arm64/include/asm/cputype.h    | 17 +++++++++-
  arch/arm64/include/asm/processor.h  |  7 +++--
  arch/arm64/kernel/cpu_errata.c      | 18 ++---------
  arch/arm64/kernel/cpufeature.c      | 17 ++++++++++
  arch/arm64/lib/copy_page.S          | 63 ++++++++++++++++++++++++++++++++-----
  6 files changed, 98 insertions(+), 27 deletions(-)

Read the cover letter in its thread