[v2,0/8] riscv: Unaligned access speed probing fixes and skipping

Message

Andrew Jones Feb. 21, 2025, 2:57 p.m. UTC

The first six patches of this series are fixes and cleanups of the
unaligned access speed probing code. The next patch introduces a
kernel command line option that allows the probing to be skipped.
This command line option is a different approach than Jesse's [1].
[1] takes a cpu-list for a particular speed, supporting heterogeneous
platforms. With this approach, the kernel command line should only
be used for homogeneous platforms. [1] also only allowed 'fast' and
'slow' to be selected. This parameter also supports 'unsupported',
which could be useful for testing code paths gated on that. The final
patch adds the documentation.

(I'd be happy to split the fixes from the new skip support if we want to
discuss the skip support independently, but I want to base on the fixes
and I'm not sure if patchwork supports Based-on: $MESSAGE_ID/$LORE_URL
or not at the moment, so I'm just posting together for now in order to
be able to check for my patchwork green lights!)

[1] https://lore.kernel.org/linux-riscv/[e-mail]/

Thanks,
drew


Andrew Jones (8):
  riscv: Annotate unaligned access init functions
  riscv: Fix riscv_online_cpu_vec
  riscv: Fix check_unaligned_access_all_cpus
  riscv: Change check_unaligned_access_speed_all_cpus to void
  riscv: Fix set up of cpu hotplug callbacks
  riscv: Fix set up of vector cpu hotplug callback
  riscv: Add parameter for skipping access speed tests
  Documentation/kernel-parameters: Add riscv unaligned speed parameters

 .../admin-guide/kernel-parameters.txt         |  16 ++
 arch/riscv/include/asm/cpufeature.h           |   4 +-
 arch/riscv/kernel/traps_misaligned.c          |  14 +-
 arch/riscv/kernel/unaligned_access_speed.c    | 212 +++++++++++-------
 4 files changed, 154 insertions(+), 92 deletions(-)