[RFC PATCH 0/3] s390: Idle time accounting improvements
From: Heiko Carstens
Date: Wed Feb 25 2026 - 09:52:24 EST
This series is on top of Frederic Weisbecker's idle cputime accounting
refactor series.
The first patch is a fix and should be merged into the corresponding patch of
the series.
The second patch is supposed to improve s390 idle time accounting, and bring
it back to the state it is was before arch_cpu_idle_time() was removed [2].
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).
The code doesn't look too nice, and, as usual, might contain bugs. Therefore
this is an RFC. Maybe the outcome is also to drop this, and stay with
Frederic's code as s390 backend.
Thanks,
Heiko
[1] https://lore.kernel.org/all/20260206142245.58987-1-frederic@xxxxxxxxxx/
[2] commit be76ea614460 ("s390/idle: remove arch_cpu_idle_time() and corresponding code")
Heiko Carstens (3):
fixup! s390/time: Prepare to stop elapsing in dynticks-idle
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 | 11 ++--
arch/s390/include/asm/lowcore.h | 9 +--
arch/s390/include/asm/timex.h | 20 +-----
arch/s390/include/asm/tod_types.h | 30 +++++++++
arch/s390/kernel/asm-offsets.c | 5 ++
arch/s390/kernel/entry.S | 7 +-
arch/s390/kernel/idle.c | 105 +++++++++++++++++++++---------
arch/s390/kernel/irq.c | 2 +-
arch/s390/kernel/setup.c | 1 +
arch/s390/kernel/smp.c | 33 +---------
arch/s390/kernel/vtime.c | 37 -----------
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, 166 insertions(+), 135 deletions(-)
create mode 100644 arch/s390/include/asm/tod_types.h
--
2.51.0