[Bug 2040027] Re: [SPR][ICX] OpenBLAS: Issues while testing sbgemm for Sapphire Rapids (SPR)

[Vladimir Petko]

** Changed in: openblas (Ubuntu Jammy)
       Status: In Progress => New

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Title:
  [SPR][ICX] OpenBLAS: Issues while testing sbgemm for Sapphire Rapids
  (SPR)

Status in intel:
  Fix Released
Status in openblas package in Ubuntu:
  Fix Released
Status in openblas source package in Jammy:
  New
Status in openblas source package in Mantic:
  Won't Fix

Bug description:
  [Impact]

  The sbgemm algorithm of openblas in Mantic and Jammy encounters 2 issues on Intel sapphire rapids platform:
  - the wrong detection of sapphire rapids as copperlake makes the sbgemm algorithm output wrong calculation.
  - the sbgemm test program encounters an illegal execution error.

  In addition to these errors, the OpenBLAS build with DYNAMIC_ARCH (see https://fossies.org/linux/OpenBLAS/README.md)
  does not work for saphhire rapids.

  [Test Plan]

  On sapphire rapids platform:

  - To check the runtime issue, run the dbgemm test program
  - To check the DYNAMIC_ARCH build support, build OpenBLAS with DYNAMIC_ARCH enabled and
    check that the sapphire rapids is supported

  [Where problems could occur]

  For the fix, most of the change is related to Intel SPR (Sapphire rapids) so i do not expect any regression on other Intel (or others) platforms.
  For sapphire rapids, the change impacts the sbgemm algorithm, so that is where i
  can see potential problems to occur

  [Other Info]

  This patchset has been integrated upstreamed for the version 0.3.24 of OpenBLAS.
  The original upstream PR can be found here : https://github.com/OpenMathLib/OpenBLAS/pull/4048/files
  The patchset contains 7 commits and modifies 11 files. Most of the changes are adding code (platform support, build support),
  the rest is modifying small/precise portion of the code (change GCC version macro, remove a constant in formula)
  The patchset applies without conflict for Mantic and it applies with a very light conflict resolution for Jammy.

  ==========
  [Description]
    Fix issues with sbgemm in Sapphire Rapids
    https://github.com/OpenMathLib/OpenBLAS/pull/4048

  [Hardware Information]
    Architecture:
      Intel / AMD (x86_64)
    Platform(s):
      Sapphire Rapids
    Date HW is expected at Canonical:

    Component(s):
      Performance and Scalability

  [Software Information]
    Target Version:
      22.04.4
    Target Kernel:
      N/A
    Commit IDs:
      TBD
    External Links:
      https://github.com/OpenMathLib/OpenBLAS

  [Business Justification]

  [Testing guidance]
  Some apps that use OpenBlas are rbenchmark, numpy, and cp2k.  These can we found via the Phoronix Test Suite.  Verify that the patches don't result in any regression.

  [External ID]
    OSVE-5181

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