Subject: [RFC PATCH 0/3] powerpc/32: nohz full support

From: Nicholas Piggin <[email-masked]>
Date: Tue, 4 Oct 2022 16:33:03 +1000

Doesn't seem to be much more involved in adding context tracking and
generic virt cpu accounting support for 32-bit, which is all that's
left to support NO_HZ_FULL.

I tested this with e5500 SMP kernel with isolated and nohz CPU, and
it seems to be doing the right thing -- periodic tick is stopped on
the nohz CPUs when they are running in userspace.

Context tracking warnings should catch quite quickly if we got
something wrong there (with the force context tracking option). I
don't have a 32-bit KVM environment to test so that might have some
issues but it should be quite easy to fix if it can be tested.

I assume the virt cpu accounting gen option removal is okay, but not
exactly sure what to look for in terms of possible problems, so we'll
see what comments that gets back.

Thanks,
Nick

Nicholas Piggin (3):
  powerpc/32: Implement HAVE_CONTEXT_TRACKING_USER support
  powerpc: remove the last remnants of cputime_t
  Remove HAVE_VIRT_CPU_ACCOUNTING_GEN option

 arch/Kconfig                         | 11 -----------
 arch/arm/Kconfig                     |  1 -
 arch/csky/Kconfig                    |  1 -
 arch/loongarch/Kconfig               |  1 -
 arch/mips/Kconfig                    |  1 -
 arch/powerpc/Kconfig                 |  2 +-
 arch/powerpc/include/asm/cputime.h   | 17 +----------------
 arch/powerpc/include/asm/interrupt.h | 21 ++++++---------------
 arch/powerpc/kernel/time.c           | 23 ++---------------------
 arch/xtensa/Kconfig                  |  1 -
 init/Kconfig                         |  1 -
 kernel/time/Kconfig                  |  2 --
 12 files changed, 10 insertions(+), 72 deletions(-)

-- 
2.37.2