1. 01 4月, 2015 8 次提交
  2. 27 3月, 2015 1 次提交
  3. 14 9月, 2014 1 次提交
    • F
      nohz: Move nohz full init call to tick init · a80e49e2
      Frederic Weisbecker 提交于
      This way we unbloat a bit main.c and more importantly we initialize
      nohz full after init_IRQ(). This dependency will be needed in further
      patches because nohz full needs irq work to raise its own IRQ.
      Information about the support for this ability on ARM64 is obtained on
      init_IRQ() which initialize the pointer to __smp_call_function.
      
      Since tick_init() is called right after init_IRQ(), this is a good place
      to call tick_nohz_init() and prepare for that dependency.
      Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      a80e49e2
  4. 24 7月, 2014 1 次提交
  5. 07 2月, 2014 3 次提交
  6. 24 12月, 2013 1 次提交
    • J
      tick/timekeeping: Call update_wall_time outside the jiffies lock · 47a1b796
      John Stultz 提交于
      Since the xtime lock was split into the timekeeping lock and
      the jiffies lock, we no longer need to call update_wall_time()
      while holding the jiffies lock.
      
      Thus, this patch splits update_wall_time() out from do_timer().
      
      This allows us to get away from calling clock_was_set_delayed()
      in update_wall_time() and instead use the standard clock_was_set()
      call that previously would deadlock, as it causes the jiffies lock
      to be acquired.
      
      Cc: Sasha Levin <sasha.levin@oracle.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
      47a1b796
  7. 03 12月, 2013 1 次提交
    • F
      nohz: Convert a few places to use local per cpu accesses · e8fcaa5c
      Frederic Weisbecker 提交于
      A few functions use remote per CPU access APIs when they
      deal with local values.
      
      Just do the right conversion to improve performance, code
      readability and debug checks.
      
      While at it, lets extend some of these function names with *_this_cpu()
      suffix in order to display their purpose more clearly.
      Signed-off-by: NFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      e8fcaa5c
  8. 19 10月, 2013 1 次提交
  9. 28 5月, 2013 1 次提交
  10. 16 5月, 2013 3 次提交
  11. 23 3月, 2013 1 次提交
  12. 07 3月, 2013 1 次提交
  13. 14 11月, 2012 1 次提交
  14. 08 9月, 2011 1 次提交
  15. 26 2月, 2011 1 次提交
    • T
      clockevents: Prevent oneshot mode when broadcast device is periodic · 3a142a06
      Thomas Gleixner 提交于
      When the per cpu timer is marked CLOCK_EVT_FEAT_C3STOP, then we only
      can switch into oneshot mode, when the backup broadcast device
      supports oneshot mode as well. Otherwise we would try to switch the
      broadcast device into an unsupported mode unconditionally. This went
      unnoticed so far as the current available broadcast devices support
      oneshot mode. Seth unearthed this problem while debugging and working
      around an hpet related BIOS wreckage.
      
      Add the necessary check to tick_is_oneshot_available().
      Reported-and-tested-by: NSeth Forshee <seth.forshee@canonical.com>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      LKML-Reference: <alpine.LFD.2.00.1102252231200.2701@localhost6.localdomain6>
      Cc: stable@kernel.org # .21 ->
      3a142a06
  16. 01 2月, 2011 2 次提交
  17. 15 12月, 2009 1 次提交
  18. 18 10月, 2008 1 次提交
    • T
      NOHZ: restart tick device from irq_enter() · fb02fbc1
      Thomas Gleixner 提交于
      We did not restart the tick device from irq_enter() to avoid double
      reprogramming and extra events in the return immediate to idle case.
      
      But long lasting softirqs can lead to a situation where jiffies become
      stale:
      
      idle()
        tick stopped (reprogrammed to next pending timer)
        halt()
         interrupt
           jiffies updated from irq_enter()
           interrupt handler
           softirq function 1 runs 20ms
           softirq function 2 arms a 10ms timer with a stale jiffies value
           jiffies updated from irq_exit()
           timer wheel has now an already expired timer
           (the one added in function 2)
           timer fires and timer softirq runs
      
      This was discovered when debugging a timer problem which happend only
      when the ath5k driver is active. The debugging proved that there is a
      softirq function running for more than 20ms, which is a bug by itself.
      
      To solve this we restart the tick timer right from irq_enter(), but do
      not go through the other functions which are necessary to return from
      idle when need_resched() is set.
      Reported-by: NElias Oltmanns <eo@nebensachen.de>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Tested-by: NElias Oltmanns <eo@nebensachen.de>
      fb02fbc1
  19. 23 9月, 2008 3 次提交
    • I
      timers: fix build error in !oneshot case · f8e256c6
      Ingo Molnar 提交于
       kernel/time/tick-common.c: In function ‘tick_setup_periodic’:
       kernel/time/tick-common.c:113: error: implicit declaration of function ‘tick_broadcast_oneshot_active’
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      f8e256c6
    • T
      clockevents: prevent mode mismatch on cpu online · 27ce4cb4
      Thomas Gleixner 提交于
      Impact: timer hang on CPU online observed on AMD C1E systems
      
      When a CPU is brought online then the broadcast machinery can
      be in the one shot state already. Check this and setup the timer 
      device of the new CPU in one shot mode so the broadcast code
      can pick up the next_event value correctly.
      
      Another AMD C1E oddity, as we switch to broadcast immediately and
      not after the full bring up via the ACPI cpu idle code.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      27ce4cb4
    • T
      clockevents: prevent cpu online to interfere with nohz · 6441402b
      Thomas Gleixner 提交于
      Impact: rare hang which can be triggered on CPU online.
      
      tick_do_timer_cpu keeps track of the CPU which updates jiffies
      via do_timer. The value -1 is used to signal, that currently no
      CPU is doing this. There are two cases, where the variable can 
      have this state:
      
       boot:
          necessary for systems where the boot cpu id can be != 0
      
       nohz long idle sleep:
          When the CPU which did the jiffies update last goes into
          a long idle sleep it drops the update jiffies duty so
          another CPU which is not idle can pick it up and keep
          jiffies going.
      
      Using the same value for both situations is wrong, as the CPU online
      code can see the -1 state when the timer of the newly onlined CPU is
      setup. The setup for a newly onlined CPU goes through periodic mode
      and can pick up the do_timer duty without being aware of the nohz /
      highres mode of the already running system.
      
      Use two separate states and make them constants to avoid magic
      numbers confusion. 
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      6441402b
  20. 17 9月, 2008 1 次提交
    • T
      clockevents: make device shutdown robust · 2344abbc
      Thomas Gleixner 提交于
      The device shut down does not cleanup the next_event variable of the
      clock event device. So when the device is reactivated the possible
      stale next_event value can prevent the device to be reprogrammed as it
      claims to wait on a event already.
      
      This is the root cause of the resurfacing suspend/resume problem,
      where systems need key press to come back to life.
      
      Fix this by setting next_event to KTIME_MAX when the device is shut
      down. Use a separate function for shutdown which takes care of that
      and only keep the direct set mode call in the broadcast code, where we
      can not touch the next_event value.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      2344abbc
  21. 05 9月, 2008 1 次提交
    • T
      clockevents: prevent endless loop lockup · 1fb9b7d2
      Thomas Gleixner 提交于
      The C1E/HPET bug reports on AMDX2/RS690 systems where tracked down to a
      too small value of the HPET minumum delta for programming an event.
      
      The clockevents code needs to enforce an interrupt event on the clock event
      device in some cases. The enforcement code was stupid and naive, as it just
      added the minimum delta to the current time and tried to reprogram the device.
      When the minimum delta is too small, then this loops forever.
      
      Add a sanity check. Allow reprogramming to fail 3 times, then print a warning
      and double the minimum delta value to make sure, that this does not happen again.
      Use the same function for both tick-oneshot and tick-broadcast code.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      1fb9b7d2
  22. 30 1月, 2008 1 次提交
  23. 09 5月, 2007 1 次提交
  24. 17 3月, 2007 1 次提交
    • T
      [PATCH] clockevents: Fix suspend/resume to disk hangs · cd05a1f8
      Thomas Gleixner 提交于
      I finally found a dual core box, which survives suspend/resume without
      crashing in the middle of nowhere. Sigh, I never figured out from the
      code and the bug reports what's going on.
      
      The observed hangs are caused by a stale state transition of the clock
      event devices, which keeps the RCU synchronization away from completion,
      when the non boot CPU is brought back up.
      
      The suspend/resume in oneshot mode needs the similar care as the
      periodic mode during suspend to RAM. My assumption that the state
      transitions during the different shutdown/bringups of s2disk would go
      through the periodic boot phase and then switch over to highres resp.
      nohz mode were simply wrong.
      
      Add the appropriate suspend / resume handling for the non periodic
      modes.
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cd05a1f8
  25. 07 3月, 2007 1 次提交
  26. 17 2月, 2007 1 次提交