[PATCH 0/4] s390: Idle time accounting improvements

[Heiko Carstens]

This series is on top of Frederic Weisbecker's idle cpu time accounting
refactor series [1][2].

This is supposed to improve s390 idle time accounting, and brings it
back to the state it was before arch_cpu_idle_time() was removed from
s390 [3].

In result all cpu time accounting is done by the s390 architecture backend
again, instead of having a mix of architecure specific and common code
accounting (common code: idle, s390 architecture: everything else).

Changes since RFC [4]:

- Split into more patches

- Fix various build errors for !CONFIG_NO_HZ_COMMON

- Get rid of private seqcount implementation and access seqcount from
  kernel_cpustat directly from assembler code, as suggested by Frederic
  Weisbecker

[1] https://lore.kernel.org/all/20260508131647.43868-1-frederic@xxxxxxxxxx/
[2] git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git timers/core-v4
[3] commit be76ea614460 ("s390/idle: remove arch_cpu_idle_time() and corresponding code")
[4] https://lore.kernel.org/all/20260225145146.1031705-1-hca@xxxxxxxxxxxxx/

Heiko Carstens (4):
  s390/timex: Move union tod_clock type to separate header
  s390/irq/idle: Use stcke instead of stckf for time stamps
  s390/idle: Provide arch specific kcpustat_field_idle()/kcpustat_field_iowait()
  s390/idle: Remove idle time and count sysfs files

 arch/s390/include/asm/idle.h      |  14 ++--
 arch/s390/include/asm/lowcore.h   |   4 +-
 arch/s390/include/asm/timex.h     |  20 +----
 arch/s390/include/asm/tod_types.h |  30 +++++++
 arch/s390/include/asm/vtime.h     |   4 +-
 arch/s390/kernel/asm-offsets.c    |   7 ++
 arch/s390/kernel/entry.S          |  14 +++-
 arch/s390/kernel/idle.c           | 129 +++++++++++++++++++++++-------
 arch/s390/kernel/irq.c            |   7 +-
 arch/s390/kernel/smp.c            |  33 +-------
 arch/s390/kernel/vtime.c          |  55 +------------
 drivers/s390/cio/qdio_main.c      |   2 +-
 drivers/s390/cio/qdio_thinint.c   |   2 +-
 include/linux/kernel_stat.h       |  27 +++++++
 include/linux/vtime.h             |   6 ++
 kernel/sched/cputime.c            |   4 +-
 16 files changed, 203 insertions(+), 155 deletions(-)
 create mode 100644 arch/s390/include/asm/tod_types.h

base-commit: e64ba052ce04e363ff76d3cb8bedc5f812188acb
-- 
2.51.0