1. 27 Jan, 2013 2 commits
    • Frederic Weisbecker's avatar
      kvm: Prepare to add generic guest entry/exit callbacks · c11f11fc
      Frederic Weisbecker authored
      
      
      Do some ground preparatory work before adding guest_enter()
      and guest_exit() context tracking callbacks. Those will
      be later used to read the guest cputime safely when we
      run in full dynticks mode.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Gleb Natapov <gleb@redhat.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Marcelo Tosatti <mtosatti@redhat.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      c11f11fc
    • Frederic Weisbecker's avatar
      cputime: Generic on-demand virtual cputime accounting · abf917cd
      Frederic Weisbecker authored
      
      
      If we want to stop the tick further idle, we need to be
      able to account the cputime without using the tick.
      
      Virtual based cputime accounting solves that problem by
      hooking into kernel/user boundaries.
      
      However implementing CONFIG_VIRT_CPU_ACCOUNTING require
      low level hooks and involves more overhead. But we already
      have a generic context tracking subsystem that is required
      for RCU needs by archs which plan to shut down the tick
      outside idle.
      
      This patch implements a generic virtual based cputime
      accounting that relies on these generic kernel/user hooks.
      
      There are some upsides of doing this:
      
      - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING
      if context tracking is already built (already necessary for RCU in full
      tickless mode).
      
      - We can rely on the generic context tracking subsystem to dynamically
      (de)activate the hooks, so that we can switch anytime between virtual
      and tick based accounting. This way we don't have the overhead
      of the virtual accounting when the tick is running periodically.
      
      And one downside:
      
      - There is probably more overhead than a native virtual based cputime
      accounting. But this relies on hooks that are already set anyway.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Li Zhong <zhong@linux.vnet.ibm.com>
      Cc: Namhyung Kim <namhyung.kim@lge.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      abf917cd
  2. 03 Jan, 2013 1 commit
    • Greg Kroah-Hartman's avatar
      IA64: drivers: remove __dev* attributes. · 5b5e76e9
      Greg Kroah-Hartman authored
      
      
      CONFIG_HOTPLUG is going away as an option.  As a result, the __dev*
      markings need to be removed.
      
      This change removes the use of __devinit, __devexit_p, __devinitdata,
      and __devexit from these drivers.
      
      Based on patches originally written by Bill Pemberton, but redone by me
      in order to handle some of the coding style issues better, by hand.
      
      Cc: Bill Pemberton <wfp5p@virginia.edu>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5b5e76e9
  3. 20 Nov, 2012 1 commit
    • Frederic Weisbecker's avatar
      vtime: Warn if irqs aren't disabled on system time accounting APIs · 1b2852b1
      Frederic Weisbecker authored
      
      
      System time accounting APIs such as vtime_account_system() and
      vtime_account_idle() need to be irqsafe. Current callers include
      irq entry, exit and kvm, all of which have been checked against that
      requirement. Now it's better to grow that with an automatic check
      in case we have further callers or we missed something.
      Suggested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      1b2852b1
  4. 19 Nov, 2012 3 commits
    • Frederic Weisbecker's avatar
      vtime: Consolidate a bit the ctx switch code · e3942ba0
      Frederic Weisbecker authored
      
      
      On ia64 and powerpc, vtime context switch only consists
      in flushing system and user pending time, plus a few
      arch housekeeping.
      
      Consolidate that into a generic implementation. s390 is
      a special case because pending user and system time accounting
      there is hard to dissociate. So it's keeping its own implementation.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Reviewed-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      e3942ba0
    • Frederic Weisbecker's avatar
      vtime: Explicitly account pending user time on process tick · bcebdf84
      Frederic Weisbecker authored
      
      
      All vtime implementations just flush the user time on process
      tick. Consolidate that in generic code by calling a user time
      accounting helper. This avoids an indirect call in ia64 and
      prepare to also consolidate vtime context switch code.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Reviewed-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      bcebdf84
    • Frederic Weisbecker's avatar
      vtime: Remove the underscore prefix invasion · fd25b4c2
      Frederic Weisbecker authored
      
      
      Prepending irq-unsafe vtime APIs with underscores was actually
      a bad idea as the result is a big mess in the API namespace that
      is even waiting to be further extended. Also these helpers
      are always called from irq safe callers except kvm. Just
      provide a vtime_account_system_irqsafe() for this specific
      case so that we can remove the underscore prefix on other
      vtime functions.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Reviewed-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      fd25b4c2
  5. 29 Oct, 2012 1 commit
    • Frederic Weisbecker's avatar
      vtime: Make vtime_account_system() irqsafe · 11113334
      Frederic Weisbecker authored
      
      
      vtime_account_system() currently has only one caller with
      vtime_account() which is irq safe.
      
      Now we are going to call it from other places like kvm where
      irqs are not always disabled by the time we account the cputime.
      
      So let's make it irqsafe. The arch implementation part is now
      prefixed with "__".
      
      vtime_account_idle() arch implementation is prefixed accordingly
      to stay consistent.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      11113334
  6. 25 Sep, 2012 4 commits
    • Frederic Weisbecker's avatar
      ia64: Reuse system and user vtime accounting functions on task switch · 9dc16f64
      Frederic Weisbecker authored
      
      
      To avoid code duplication.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      9dc16f64
    • Frederic Weisbecker's avatar
      ia64: Consolidate user vtime accounting · 5bf412cd
      Frederic Weisbecker authored
      
      
      Factorize the code that accounts user time into a
      single function to avoid code duplication.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      5bf412cd
    • Frederic Weisbecker's avatar
      vtime: Consolidate system/idle context detection · a7e1a9e3
      Frederic Weisbecker authored
      
      
      Move the code that finds out to which context we account the
      cputime into generic layer.
      
      Archs that consider the whole time spent in the idle task as idle
      time (ia64, powerpc) can rely on the generic vtime_account()
      and implement vtime_account_system() and vtime_account_idle(),
      letting the generic code to decide when to call which API.
      
      Archs that have their own meaning of idle time, such as s390
      that only considers the time spent in CPU low power mode as idle
      time, can just override vtime_account().
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      a7e1a9e3
    • Frederic Weisbecker's avatar
      cputime: Use a proper subsystem naming for vtime related APIs · bf9fae9f
      Frederic Weisbecker authored
      
      
      Use a naming based on vtime as a prefix for virtual based
      cputime accounting APIs:
      
      - account_system_vtime() -> vtime_account()
      - account_switch_vtime() -> vtime_task_switch()
      
      It makes it easier to allow for further declension such
      as vtime_account_system(), vtime_account_idle(), ... if we
      want to find out the context we account to from generic code.
      
      This also make it better to know on which subsystem these APIs
      refer to.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      bf9fae9f
  7. 24 Sep, 2012 2 commits
    • John Stultz's avatar
      time: Convert CONFIG_GENERIC_TIME_VSYSCALL to CONFIG_GENERIC_TIME_VSYSCALL_OLD · 70639421
      John Stultz authored
      
      
      To help migrate archtectures over to the new update_vsyscall method,
      redfine CONFIG_GENERIC_TIME_VSYSCALL as CONFIG_GENERIC_TIME_VSYSCALL_OLD
      
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Paul Turner <pjt@google.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
      70639421
    • John Stultz's avatar
      time: Move update_vsyscall definitions to timekeeper_internal.h · 189374ae
      John Stultz authored
      
      
      Since users will need to include timekeeper_internal.h, move
      update_vsyscall definitions to timekeeper_internal.h.
      
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Paul Turner <pjt@google.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
      189374ae
  8. 20 Aug, 2012 1 commit
    • Frederic Weisbecker's avatar
      cputime: Consolidate vtime handling on context switch · baa36046
      Frederic Weisbecker authored
      
      
      The archs that implement virtual cputime accounting all
      flush the cputime of a task when it gets descheduled
      and sometimes set up some ground initialization for the
      next task to account its cputime.
      
      These archs all put their own hooks in their context
      switch callbacks and handle the off-case themselves.
      
      Consolidate this by creating a new account_switch_vtime()
      callback called in generic code right after a context switch
      and that these archs must implement to flush the prev task
      cputime and initialize the next task cputime related state.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Peter Zijlstra <peterz@infradead.org>
      baa36046
  9. 28 Mar, 2012 1 commit
  10. 15 Mar, 2012 1 commit
  11. 14 Jul, 2011 1 commit
  12. 24 May, 2011 1 commit
  13. 21 Feb, 2011 1 commit
  14. 31 Jan, 2011 1 commit
    • Torben Hohn's avatar
      ia64: Switch do_timer() to xtime_update() · 1aabd67d
      Torben Hohn authored
      
      
      local_cpu_data->itm_next = new_itm; does not need to be protected by
      xtime_lock. xtime_update() takes the lock itself.
      Signed-off-by: default avatarTorben Hohn <torbenh@gmx.de>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: johnstul@us.ibm.com
      Cc: hch@infradead.org
      Cc: yong.zhang0@gmail.com
      LKML-Reference: <20110127145956.23248.49107.stgit@localhost>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      1aabd67d
  15. 28 Dec, 2010 1 commit
  16. 27 Jul, 2010 1 commit
    • John Stultz's avatar
      timkeeping: Fix update_vsyscall to provide wall_to_monotonic offset · 7615856e
      John Stultz authored
      
      
      update_vsyscall() did not provide the wall_to_monotoinc offset,
      so arch specific implementations tend to reference wall_to_monotonic
      directly. This limits future cleanups in the timekeeping core, so
      this patch fixes the update_vsyscall interface to provide
      wall_to_monotonic, allowing wall_to_monotonic to be made static
      as planned in Documentation/feature-removal-schedule.txt
      Signed-off-by: default avatarJohn Stultz <johnstul@us.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Anton Blanchard <anton@samba.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Tony Luck <tony.luck@intel.com>
      LKML-Reference: <1279068988-21864-7-git-send-email-johnstul@us.ibm.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      7615856e
  17. 12 Mar, 2010 1 commit
    • John Stultz's avatar
      ia64: Convert ia64 to use read/update_persistent_clock · 6ffdc577
      John Stultz authored
      
      
      This patch converts the ia64 architecture to use the generic
      read_persistent_clock and update_persistent_clock interfaces, reducing
      the amount of arch specific code we have to maintain, and allowing for
      further cleanups in the future.
      
      I have not built or tested this patch, so help from arch maintainers
      would be appreciated.
      Signed-off-by: default avatarJohn Stultz <johnstul@us.ibm.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Fenghua Yu <fenghua.yu@intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      LKML-Reference: <1267675049-12337-8-git-send-email-johnstul@us.ibm.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      6ffdc577
  18. 05 Feb, 2010 1 commit
  19. 17 Nov, 2009 1 commit
    • Lin Ming's avatar
      timekeeping: Fix clock_gettime vsyscall time warp · 0696b711
      Lin Ming authored
      Since commit 0a544198
      
       "timekeeping: Move NTP adjusted clock multiplier
      to struct timekeeper" the clock multiplier of vsyscall is updated with
      the unmodified clock multiplier of the clock source and not with the
      NTP adjusted multiplier of the timekeeper.
      
      This causes user space observerable time warps:
      new CLOCK-warp maximum: 120 nsecs,  00000025c337c537 -> 00000025c337c4bf
      
      Add a new argument "mult" to update_vsyscall() and hand in the
      timekeeping internal NTP adjusted multiplier.
      Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
      Cc: "Zhang Yanmin" <yanmin_zhang@linux.intel.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Tony Luck <tony.luck@intel.com>
      LKML-Reference: <1258436990.17765.83.camel@minggr.sh.intel.com>
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      0696b711
  20. 17 Jun, 2009 1 commit
    • Matthew Wilcox's avatar
      [IA64] Convert ia64 to use int-ll64.h · e088a4ad
      Matthew Wilcox authored
      
      
      It is generally agreed that it would be beneficial for u64 to be an
      unsigned long long on all architectures.  ia64 (in common with several
      other 64-bit architectures) currently uses unsigned long.  Migrating
      piecemeal is too painful; this giant patch fixes all compilation warnings
      and errors that come as a result of switching to use int-ll64.h.
      
      Note that userspace will still see __u64 defined as unsigned long.  This
      is important as it affects C++ name mangling.
      
      [Updated by Tony Luck to change efi.h:efi_freemem_callback_t to use
       u64 for start/end rather than unsigned long]
      Signed-off-by: default avatarMatthew Wilcox <willy@linux.intel.com>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      e088a4ad
  21. 21 Apr, 2009 1 commit
  22. 01 Apr, 2009 1 commit
  23. 26 Mar, 2009 1 commit
  24. 31 Dec, 2008 2 commits
    • Martin Schwidefsky's avatar
      [PATCH] idle cputime accounting · 79741dd3
      Martin Schwidefsky authored
      
      
      The cpu time spent by the idle process actually doing something is
      currently accounted as idle time. This is plain wrong, the architectures
      that support VIRT_CPU_ACCOUNTING=y can do better: distinguish between the
      time spent doing nothing and the time spent by idle doing work. The first
      is accounted with account_idle_time and the second with account_system_time.
      The architectures that use the account_xxx_time interface directly and not
      the account_xxx_ticks interface now need to do the check for the idle
      process in their arch code. In particular to improve the system vs true
      idle time accounting the arch code needs to measure the true idle time
      instead of just testing for the idle process.
      To improve the tick based accounting as well we would need an architecture
      primitive that can tell us if the pt_regs of the interrupted context
      points to the magic instruction that halts the cpu.
      
      In addition idle time is no more added to the stime of the idle process.
      This field now contains the system time of the idle process as it should
      be. On systems without VIRT_CPU_ACCOUNTING this will always be zero as
      every tick that occurs while idle is running will be accounted as idle
      time.
      
      This patch contains the necessary common code changes to be able to
      distinguish idle system time and true idle time. The architectures with
      support for VIRT_CPU_ACCOUNTING need some changes to exploit this.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      79741dd3
    • Martin Schwidefsky's avatar
      [PATCH] fix scaled & unscaled cputime accounting · 457533a7
      Martin Schwidefsky authored
      
      
      The utimescaled / stimescaled fields in the task structure and the
      global cpustat should be set on all architectures. On s390 the calls
      to account_user_time_scaled and account_system_time_scaled never have
      been added. In addition system time that is accounted as guest time
      to the user time of a process is accounted to the scaled system time
      instead of the scaled user time.
      To fix the bugs and to prevent future forgetfulness this patch merges
      account_system_time_scaled into account_system_time and
      account_user_time_scaled into account_user_time.
      
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Cc: Tony Luck <tony.luck@intel.com>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: Chris Wright <chrisw@sous-sol.org>
      Cc: Michael Neuling <mikey@neuling.org>
      Acked-by: default avatarPaul Mackerras <paulus@samba.org>
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      457533a7
  25. 30 Jun, 2008 1 commit
  26. 27 May, 2008 1 commit
  27. 30 Apr, 2008 1 commit
  28. 20 Feb, 2008 1 commit
    • Hidetoshi Seto's avatar
      [IA64] VIRT_CPU_ACCOUNTING (accurate cpu time accounting) · b64f34cd
      Hidetoshi Seto authored
      
      
      This patch implements VIRT_CPU_ACCOUNTING for ia64,
      which enable us to use more accurate cpu time accounting.
      
      The VIRT_CPU_ACCOUNTING is an item of kernel config, which s390
      and powerpc arch have.  By turning this config on, these archs
      change the mechanism of cpu time accounting from tick-sampling
      based one to state-transition based one.
      
      The state-transition based accounting is done by checking time
      (cycle counter in processor) at every state-transition point,
      such as entrance/exit of kernel, interrupt, softirq etc.
      The difference between point to point is the actual time consumed
      during in the state. There is no doubt about that this value is
      more accurate than that of tick-sampling based accounting.
      Signed-off-by: default avatarHidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      b64f34cd
  29. 08 Feb, 2008 1 commit
  30. 25 Jan, 2008 1 commit
  31. 18 Oct, 2007 1 commit
  32. 01 Aug, 2007 1 commit
    • Christoph Lameter's avatar
      [IA64] ITC: Reduce rating for ITC clock if ITCs are drifty · b718f91c
      Christoph Lameter authored
      
      
      Make sure to reduce the rating of the ITC clock if ITCs are drifty. If they
      are drifting then we have not synchronized the ITC values, nor are we doing
      the jitter compensation (useless since drift may increase the differentials
      arbitrarily).
      
      Without this patch it is possible that the ITC clock becomes selected as
      the system clock on systems with drifty ITCs which will result in
      nanosleep hanging.
      
      One can still select the itc clock manually on such systems via
      
      clocksource=itc
      
      (Produces nice hangs on SGI Altix.)
      Signed-off-by: default avatarChristoph Lameter <clameter@sgi.com>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      b718f91c