1. 15 Aug, 2008 5 commits
  2. 11 Aug, 2008 3 commits
    • Ingo Molnar's avatar
      rcu, debug: detect stalled grace periods, cleanups · 78635fc7
      Ingo Molnar authored
      small cleanups.
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      78635fc7
    • Paul E. McKenney's avatar
      rcu, debug: detect stalled grace periods · 67182ae1
      Paul E. McKenney authored
      this is a diagnostic patch for Classic RCU.
      
      The approach is to record a timestamp at the beginning
      of the grace period (in rcu_start_batch()), then have
      rcu_check_callbacks() complain if:
      
       1.	it is running on a CPU that has holding up grace periods for
       	a long time (say one second).  This will identify the culprit
       	assuming that the culprit has not disabled hardware irqs,
       	instruction execution, or some such.
      
       2.	it is running on a CPU that is not holding up grace periods,
       	but grace periods have been held up for an even longer time
       	(say two seconds).
      
      It is enabled via the default-off CONFIG_DEBUG_RCU_STALL kernel parameter.
      
      Rather than exponential backoff, it backs off to once per 30 seconds.
      My feeling upon thinking on it was that if you have stalled RCU grace
      periods for that long, a few extra printk() messages are probably the
      least of your worries...
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Yinghai Lu <yhlu.kernel@gmail.com>
      Cc: David Witbrodt <dawitbro@sbcglobal.net>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      67182ae1
    • Ingo Molnar's avatar
      Merge branch 'linus' into core/rcu · c4c0c56a
      Ingo Molnar authored
      c4c0c56a
  3. 08 Aug, 2008 32 commits