1. 12 Apr, 2017 1 commit
  2. 14 Jun, 2016 1 commit
  3. 06 Oct, 2015 1 commit
  4. 17 Jul, 2015 2 commits
  5. 16 Jan, 2015 1 commit
  6. 06 Jan, 2015 2 commits
    • Paul E. McKenney's avatar
      rcu: Improve diagnostics for spurious RCU CPU stall warnings · 6ccd2ecd
      Paul E. McKenney authored
      The current RCU CPU stall warning code will print "Stall ended before
      state dump start" any time that the stall-warning code is triggered on
      a CPU that has already reported a quiescent state for the current grace
      period and if all quiescent states have been reported for the current
      grace period.  However, a true stall can result in these symptoms, for
      example, by preventing RCU's grace-period kthreads from ever running
      
      This commit therefore checks for this condition, reporting the end of
      the stall only if one of the grace-period counters has actually advanced.
      Otherwise, it reports the last time that the grace-period kthread made
      meaningful progress.  (In normal situations, the grace-period kthread
      should make meaningful progress at least every jiffies_till_next_fqs
      jiffies.)
      Reported-by: default avatarMiroslav Benes <mbenes@suse.cz>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Tested-by: default avatarMiroslav Benes <mbenes@suse.cz>
      6ccd2ecd
    • Xie XiuQi's avatar
      documentation: Update sysfs path for rcu_cpu_stall_timeout · 84596ccb
      Xie XiuQi authored
      Commit 6bfc09e2 ("rcu: Provide RCU CPU stall warnings for tiny RCU")
      moved the rcu_cpu_stall_timeout module parameter from rcutree.c to
      rcupdate.c, but failed to update Documentation/RCU/stallwarn.txt. This
      commit therefore repairs this omission.
      
      commit 96224daa ("documentation: Update sysfs path for rcu_cpu_stall_suppress")
      updated the path for rcu_cpu_stall_suppress, but failed to update for
      rcu_cpu_stall_timeout.
      Signed-off-by: default avatarXie XiuQi <xiexiuqi@huawei.com>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      84596ccb
  7. 29 Oct, 2014 1 commit
  8. 28 Oct, 2014 1 commit
    • Paul E. McKenney's avatar
      rcu: Remove CONFIG_RCU_CPU_STALL_VERBOSE · 0eafa468
      Paul E. McKenney authored
      The CONFIG_RCU_CPU_STALL_VERBOSE Kconfig parameter causes preemptible
      RCU's CPU stall warnings to dump out any preempted tasks that are blocking
      the current RCU grace period.  This information is useful, and the default
      has been CONFIG_RCU_CPU_STALL_VERBOSE=y for some years.  It is therefore
      time for this commit to remove this Kconfig parameter, so that future
      kernel builds will always act as if CONFIG_RCU_CPU_STALL_VERBOSE=y.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      0eafa468
  9. 07 Sep, 2014 1 commit
  10. 29 Apr, 2014 1 commit
  11. 25 Sep, 2013 1 commit
  12. 03 Apr, 2013 1 commit
    • Frederic Weisbecker's avatar
      nohz: Rename CONFIG_NO_HZ to CONFIG_NO_HZ_COMMON · 3451d024
      Frederic Weisbecker authored
      We are planning to convert the dynticks Kconfig options layout
      into a choice menu. The user must be able to easily pick
      any of the following implementations: constant periodic tick,
      idle dynticks, full dynticks.
      
      As this implies a mutual exclusion, the two dynticks implementions
      need to converge on the selection of a common Kconfig option in order
      to ease the sharing of a common infrastructure.
      
      It would thus seem pretty natural to reuse CONFIG_NO_HZ to
      that end. It already implements all the idle dynticks code
      and the full dynticks depends on all that code for now.
      So ideally the choice menu would propose CONFIG_NO_HZ_IDLE and
      CONFIG_NO_HZ_EXTENDED then both would select CONFIG_NO_HZ.
      
      On the other hand we want to stay backward compatible: if
      CONFIG_NO_HZ is set in an older config file, we want to
      enable CONFIG_NO_HZ_IDLE by default.
      
      But we can't afford both at the same time or we run into
      a circular dependency:
      
      1) CONFIG_NO_HZ_IDLE and CONFIG_NO_HZ_EXTENDED both select
         CONFIG_NO_HZ
      2) If CONFIG_NO_HZ is set, we default to CONFIG_NO_HZ_IDLE
      
      We might be able to support that from Kconfig/Kbuild but it
      may not be wise to introduce such a confusing behaviour.
      
      So to solve this, create a new CONFIG_NO_HZ_COMMON option
      which gathers the common code between idle and full dynticks
      (that common code for now is simply the idle dynticks code)
      and select it from their referring Kconfig.
      
      Then we'll later create CONFIG_NO_HZ_IDLE and map CONFIG_NO_HZ
      to it for backward compatibility.
      Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Chris Metcalf <cmetcalf@tilera.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Geoff Levand <geoff@infradead.org>
      Cc: Gilad Ben Yossef <gilad@benyossef.com>
      Cc: Hakan Akkan <hakanakkan@gmail.com>
      Cc: Ingo Molnar <mingo@kernel.org>
      Cc: Kevin Hilman <khilman@linaro.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>
      3451d024
  13. 13 Mar, 2013 1 commit
  14. 23 Sep, 2012 1 commit
  15. 21 Feb, 2012 1 commit
  16. 11 Dec, 2011 2 commits
  17. 06 May, 2011 1 commit
    • Paul E. McKenney's avatar
      rcu: Remove conditional compilation for RCU CPU stall warnings · a00e0d71
      Paul E. McKenney authored
      The RCU CPU stall warnings can now be controlled using the
      rcu_cpu_stall_suppress boot-time parameter or via the same parameter
      from sysfs.  There is therefore no longer any reason to have
      kernel config parameters for this feature.  This commit therefore
      removes the RCU_CPU_STALL_DETECTOR and RCU_CPU_STALL_DETECTOR_RUNNABLE
      kernel config parameters.  The RCU_CPU_STALL_TIMEOUT parameter remains
      to allow the timeout to be tuned and the RCU_CPU_STALL_VERBOSE parameter
      remains to allow task-stall information to be suppressed if desired.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Reviewed-by: default avatarJosh Triplett <josh@joshtriplett.org>
      a00e0d71
  18. 23 Aug, 2010 1 commit
  19. 10 May, 2010 1 commit
  20. 16 Jan, 2010 1 commit
    • Paul E. McKenney's avatar
      rcu: 1Q2010 update for RCU documentation · 4c54005c
      Paul E. McKenney authored
      Add expedited functions.  Review documentation and update
      obsolete verbiage.  Also fix the advice for the RCU CPU-stall
      kernel configuration parameter, and document RCU CPU-stall
      warnings.
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: laijs@cn.fujitsu.com
      Cc: dipankar@in.ibm.com
      Cc: mathieu.desnoyers@polymtl.ca
      Cc: josh@joshtriplett.org
      Cc: dvhltc@us.ibm.com
      Cc: niv@us.ibm.com
      Cc: peterz@infradead.org
      Cc: rostedt@goodmis.org
      Cc: Valdis.Kletnieks@vt.edu
      Cc: dhowells@redhat.com
      LKML-Reference: <12635142581866-git-send-email->
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      4c54005c