1. 05 1月, 2009 1 次提交
    • P
      rcu: fix rcutree grace-period-latency bug on small systems · c12172c0
      Paul E. McKenney 提交于
      Impact: fix delays during bootup
      
      Kudos to Andi Kleen for finding a grace-period-latency problem!  The
      problem was that the special-case code for small machines never updated
      the ->signaled field to indicate that grace-period initialization had
      completed, which prevented force_quiescent_state() from ever expediting
      grace periods.  This problem resulted in grace periods extending for more
      than 20 seconds.  Not subtle.  I introduced this bug during my inspection
      process when I fixed a race between grace-period initialization and
      force_quiescent_state() execution.
      
      The following patch properly updates the ->signaled field for the
      "small"-system case (no more than 32 CPUs for 32-bit kernels and no more
      than 64 CPUs for 64-bit kernels).
      Reported-by: NAndi Kleen <andi@firstfloor.org>
      Tested-by: NAndi Kleen <andi@firstfloor.org>
      Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      c12172c0
  2. 04 1月, 2009 27 次提交
  3. 03 1月, 2009 12 次提交