[PATCH 00/36] cputime: Convert core use of cputime_t to nsecs

[Frederic Weisbecker <fweisbec@gmail.com>]

I'm sorry for the patchbomb, especially as I usually complain about
these myself but I don't see any way to split this patchset into
standalone pieces, none of which would make any sense... All I can do
is to isolate about 3 cleanup patches.

So currently, cputime_t serves the purpose, for s390 and
powerpc (on CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y), to avoid converting
arch clock counters to nanosecs or jiffies while accounting cputime.

But this comes at the cost of a lot of complexity and uglification
in the core code to deal with such an opaque type that relies on lots of
mutators and accessors in order to deal with a random granularity time
unit that also involve lots of workarounds and likely some performance
penalties.

So this patchset proposes to convert most of the cputime_t uses to nsecs.
In the end it's only used by s390 and powerpc. This all comes at the
expense of those two archs which then need to perform a cputime_to_nsec()
conversion everytime they update the cputime to the core. Now I expect
we can leverage this performance loss with flushing the cputime only on
ticks so that we accumulate time as cputime_t in between and make the
conversions more rare.

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
	cputime/nsecs-v2

HEAD: cf109941db5da247569ee99a6effe00f62537082

Thanks,
	Frederic
---

Frederic Weisbecker (36):
      jiffies: Reuse TICK_NSEC instead of NSEC_PER_JIFFY
      time: Introduce jiffies64_to_nsecs()
      sched: Remove unused INIT_CPUTIME macro
      cputime: Convert kcpustat to nsecs
      macintosh/rack-meter: Remove cputime_t internal use
      cputime: Convert guest time accounting to nsecs
      cputime: Special API to return old-typed cputime
      cputime: Convert task/group cputime to nsecs
      alpha: Convert obsolete cputime_t to nsecs
      x86: Convert obsolete cputime type to nsecs
      isdn: Convert obsolete cputime type to nsecs
      binfmt: Convert obsolete cputime type to nsecs
      acct: Convert obsolete cputime type to nsecs
      delaycct: Convert obsolete cputime type to nsecs
      tsacct: Convert obsolete cputime type to nsecs
      signal: Convert obsolete cputime type to nsecs
      cputime: Increment kcpustat directly on irqtime account
      posix-timers: Use TICK_NSEC instead of a dynamically ad-hoc calculated version
      posix-timers: Convert internals to use nsecs
      itimer: Convert internal cputime_t units to nsec
      sched: Remove temporary cputime_t accessors
      cputime: Push time to account_user_time() in nsecs
      cputime: Push time to account_steal_time() in nsecs
      cputime: Push time to account_idle_time() in nsecs
      cputime: Push time to account_system_time() in nsecs
      cputime: Complete nsec conversion of tick based accounting
      vtime: Return nsecs instead of cputime_t to account
      cputime: Remove jiffies based cputime
      ia64: Move nsecs based cputime headers to the last arch using it
      ia64: Convert vtime to use nsec units directly
      ia64: Remove unused cputime definitions
      s390: Make arch_cpu_idle_time() to return nsecs
      powerpc: Remove unused cputime definitions
      s390: Remove unused cputime definitions
      cputime: Remove unused nsec_to_cputime
      cputime: Remove asm generic headers


 arch/alpha/include/asm/Kbuild         |   1 -
 arch/alpha/kernel/osf_sys.c           |  10 +-
 arch/arc/include/asm/Kbuild           |   1 -
 arch/arm/include/asm/Kbuild           |   1 -
 arch/arm64/include/asm/Kbuild         |   1 -
 arch/avr32/include/asm/Kbuild         |   1 -
 arch/blackfin/include/asm/Kbuild      |   1 -
 arch/c6x/include/asm/Kbuild           |   1 -
 arch/cris/include/asm/Kbuild          |   1 -
 arch/frv/include/asm/Kbuild           |   1 -
 arch/h8300/include/asm/Kbuild         |   1 -
 arch/hexagon/include/asm/Kbuild       |   1 -
 arch/ia64/include/asm/cputime.h       |   6 +-
 arch/ia64/kernel/head.S               |   4 +-
 arch/ia64/kernel/time.c               |  14 +--
 arch/m32r/include/asm/Kbuild          |   1 -
 arch/m68k/include/asm/Kbuild          |   1 -
 arch/metag/include/asm/Kbuild         |   1 -
 arch/microblaze/include/asm/Kbuild    |   1 -
 arch/mips/include/asm/Kbuild          |   1 -
 arch/mips/kernel/binfmt_elfn32.c      |  11 ---
 arch/mips/kernel/binfmt_elfo32.c      |  11 ---
 arch/mn10300/include/asm/Kbuild       |   1 -
 arch/nios2/include/asm/Kbuild         |   1 -
 arch/openrisc/include/asm/Kbuild      |   1 -
 arch/parisc/include/asm/Kbuild        |   1 -
 arch/parisc/kernel/binfmt_elf32.c     |  10 --
 arch/powerpc/include/asm/cputime.h    | 177 +---------------------------------
 arch/powerpc/kernel/time.c            |  33 ++-----
 arch/s390/appldata/appldata_os.c      |  16 +--
 arch/s390/include/asm/cputime.h       | 109 +--------------------
 arch/s390/kernel/idle.c               |   7 +-
 arch/s390/kernel/vtime.c              |  14 +--
 arch/score/include/asm/Kbuild         |   1 -
 arch/sh/include/asm/Kbuild            |   1 -
 arch/sparc/include/asm/Kbuild         |   1 -
 arch/tile/include/asm/Kbuild          |   1 -
 arch/um/include/asm/Kbuild            |   1 -
 arch/unicore32/include/asm/Kbuild     |   1 -
 arch/x86/include/asm/Kbuild           |   1 -
 arch/x86/kernel/apm_32.c              |   6 +-
 arch/x86/kvm/hyperv.c                 |   5 +-
 arch/xtensa/include/asm/Kbuild        |   1 -
 drivers/cpufreq/cpufreq.c             |   6 +-
 drivers/cpufreq/cpufreq_governor.c    |   2 +-
 drivers/cpufreq/cpufreq_stats.c       |   1 -
 drivers/isdn/mISDN/stack.c            |   4 +-
 drivers/macintosh/rack-meter.c        |  28 +++---
 fs/binfmt_elf.c                       |  15 +--
 fs/binfmt_elf_fdpic.c                 |  14 +--
 fs/compat_binfmt_elf.c                |  20 ++--
 fs/proc/array.c                       |  16 +--
 fs/proc/stat.c                        |  64 ++++++------
 fs/proc/uptime.c                      |   7 +-
 include/asm-generic/cputime.h         |  15 ---
 include/asm-generic/cputime_jiffies.h |  75 --------------
 include/asm-generic/cputime_nsecs.h   | 121 -----------------------
 include/linux/cputime.h               |   7 +-
 include/linux/jiffies.h               |   2 +
 include/linux/kernel_stat.h           |   9 +-
 include/linux/posix-timers.h          |  14 +--
 include/linux/sched.h                 |  62 +++++-------
 include/trace/events/timer.h          |  26 ++---
 kernel/acct.c                         |   7 +-
 kernel/delayacct.c                    |   6 +-
 kernel/exit.c                         |   4 +-
 kernel/fork.c                         |   2 +-
 kernel/sched/cpuacct.c                |   2 +-
 kernel/sched/cputime.c                | 165 +++++++++++++------------------
 kernel/sched/sched.h                  |   7 +-
 kernel/sched/stats.h                  |   4 +-
 kernel/signal.c                       |  12 +--
 kernel/sys.c                          |  16 +--
 kernel/time/itimer.c                  |  60 ++++--------
 kernel/time/jiffies.c                 |  32 +++---
 kernel/time/posix-cpu-timers.c        | 170 ++++++++++++--------------------
 kernel/time/time.c                    |  10 ++
 kernel/time/timeconst.bc              |   6 ++
 kernel/tsacct.c                       |  21 ++--
 79 files changed, 408 insertions(+), 1085 deletions(-)