Re: [PATCH 0/4] cputime: some optimizations and cleanups

Frederic Weisbecker
2016-11-09T13:01:25Z

2016-10-31 12:36 GMT+00:00 Stanislaw Gruszka <sgruszka@redhat.com>:
> Patches remove accounting of utimescaled/stimescaled on architectures
> that do not provide those values (scaled cputimes are equal to normal
> cputimes) what is every architecture except powerpc and s390.
>
> Patches do not change user visible behaviour.
>
> There is very little documentation how scaled cputimes should be
> interpreted and what useful information they provide (at least
> I could not find that). Moreover they are exported to user-space
> only via not commonly used taskstats and delayacct interfaces (i.e.
> interfaces that are not used by standard linux tools AFICT). However
> I assume they can not be removed by whole (i.e. replaced by normal
> utimes/stimes on powerpc and s390).
>
> Stanislaw Gruszka (4):
> cputime/powerpc: remove cputime_last_delta global variable
> cputime/powerpc: remove cputime_to_scaled()
> cputime/powerpc/s390: make scaled cputime arch specific
> cputime: simplify task_cputime()
>
> arch/ia64/kernel/time.c | 4 +-
> arch/powerpc/Kconfig | 1 +
> arch/powerpc/include/asm/cputime.h | 14 ----
> arch/powerpc/kernel/time.c | 8 +-
> arch/s390/Kconfig | 1 +
> arch/s390/kernel/vtime.c | 9 ++-
> arch/x86/kernel/apm_32.c | 4 +-
> include/asm-generic/cputime_jiffies.h | 1 -
> include/asm-generic/cputime_nsecs.h | 1 -
> include/linux/kernel_stat.h | 4 +-
> include/linux/sched.h | 29 +++++---
> kernel/fork.c | 2 +
> kernel/sched/cputime.c | 124 +++++++++------------------------
> kernel/time/posix-cpu-timers.c | 4 +-
> 14 files changed, 73 insertions(+), 133 deletions(-)
>

Excellent patchset!
Thanks a lot Stanislaw!

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>