1. 01 5月, 2012 1 次提交
  2. 25 4月, 2012 1 次提交
  3. 22 2月, 2012 5 次提交
  4. 17 1月, 2012 2 次提交
  5. 12 12月, 2011 6 次提交
  6. 29 9月, 2011 6 次提交
  7. 27 7月, 2011 1 次提交
  8. 09 7月, 2011 1 次提交
  9. 06 5月, 2011 4 次提交
  10. 05 3月, 2011 1 次提交
  11. 08 10月, 2010 1 次提交
  12. 24 9月, 2010 1 次提交
  13. 20 8月, 2010 1 次提交
  14. 09 6月, 2010 1 次提交
  15. 12 5月, 2010 1 次提交
  16. 07 5月, 2010 1 次提交
    • T
      sched: replace migration_thread with cpu_stop · 969c7921
      Tejun Heo 提交于
      Currently migration_thread is serving three purposes - migration
      pusher, context to execute active_load_balance() and forced context
      switcher for expedited RCU synchronize_sched.  All three roles are
      hardcoded into migration_thread() and determining which job is
      scheduled is slightly messy.
      
      This patch kills migration_thread and replaces all three uses with
      cpu_stop.  The three different roles of migration_thread() are
      splitted into three separate cpu_stop callbacks -
      migration_cpu_stop(), active_load_balance_cpu_stop() and
      synchronize_sched_expedited_cpu_stop() - and each use case now simply
      asks cpu_stop to execute the callback as necessary.
      
      synchronize_sched_expedited() was implemented with private
      preallocated resources and custom multi-cpu queueing and waiting
      logic, both of which are provided by cpu_stop.
      synchronize_sched_expedited_count is made atomic and all other shared
      resources along with the mutex are dropped.
      
      synchronize_sched_expedited() also implemented a check to detect cases
      where not all the callback got executed on their assigned cpus and
      fall back to synchronize_sched().  If called with cpu hotplug blocked,
      cpu_stop already guarantees that and the condition cannot happen;
      otherwise, stop_machine() would break.  However, this patch preserves
      the paranoid check using a cpumask to record on which cpus the stopper
      ran so that it can serve as a bisection point if something actually
      goes wrong theree.
      
      Because the internal execution state is no longer visible,
      rcu_expedited_torture_stats() is removed.
      
      This patch also renames cpu_stop threads to from "stopper/%d" to
      "migration/%d".  The names of these threads ultimately don't matter
      and there's no reason to make unnecessary userland visible changes.
      
      With this patch applied, stop_machine() and sched now share the same
      resources.  stop_machine() is faster without wasting any resources and
      sched migration users are much cleaner.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NPeter Zijlstra <peterz@infradead.org>
      Cc: Ingo Molnar <mingo@elte.hu>
      Cc: Dipankar Sarma <dipankar@in.ibm.com>
      Cc: Josh Triplett <josh@freedesktop.org>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      969c7921
  17. 25 2月, 2010 2 次提交
    • P
      rcu: Fix rcutorture mod_timer argument to delay one jiffy · 6155fec9
      Paul E. McKenney 提交于
      The current "mod_timer(&t, 1)" potentially makes the timer fire
      immediately, change this to wait one jiffy.
      Signed-off-by: NDan Carpenter <error27@gmail.com>
      Signed-off-by: NPaul 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: <1266887105-1528-20-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      6155fec9
    • P
      rcu: Introduce lockdep-based checking to RCU read-side primitives · 632ee200
      Paul E. McKenney 提交于
      Inspection is proving insufficient to catch all RCU misuses,
      which is understandable given that rcu_dereference() might be
      protected by any of four different flavors of RCU (RCU, RCU-bh,
      RCU-sched, and SRCU), and might also/instead be protected by any
      of a number of locking primitives. It is therefore time to
      enlist the aid of lockdep.
      
      This set of patches is inspired by earlier work by Peter
      Zijlstra and Thomas Gleixner, and takes the following approach:
      
      o	Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched.
      
      o	Set up separate lockdep classes for each instance of SRCU.
      
      o	Create primitives that check for being in an RCU read-side
      	critical section.  These return exact answers if lockdep is
      	fully enabled, but if unsure, report being in an RCU read-side
      	critical section.  (We want to avoid false positives!)
      	The primitives are:
      
      	For RCU: rcu_read_lock_held(void)
      
      	For RCU-bh: rcu_read_lock_bh_held(void)
      
      	For RCU-sched: rcu_read_lock_sched_held(void)
      
      	For SRCU: srcu_read_lock_held(struct srcu_struct *sp)
      
      o	Add rcu_dereference_check(), which takes a second argument
      	in which one places a boolean expression based on the above
      	primitives and/or lockdep_is_held().
      
      o	A new kernel configuration parameter, CONFIG_PROVE_RCU, enables
      	rcu_dereference_check().  This depends on CONFIG_PROVE_LOCKING,
      	and should be quite helpful during the transition period while
      	CONFIG_PROVE_RCU-unaware patches are in flight.
      
      The existing rcu_dereference() primitive does no checking, but
      upcoming patches will change that.
      Signed-off-by: NPaul 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: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      632ee200
  18. 13 1月, 2010 1 次提交
  19. 03 12月, 2009 1 次提交
    • P
      rcu: Add expedited grace-period support for preemptible RCU · d9a3da06
      Paul E. McKenney 提交于
      Implement an synchronize_rcu_expedited() for preemptible RCU
      that actually is expedited.  This uses
      synchronize_sched_expedited() to force all threads currently
      running in a preemptible-RCU read-side critical section onto the
      appropriate ->blocked_tasks[] list, then takes a snapshot of all
      of these lists and waits for them to drain.
      Signed-off-by: NPaul 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: <1259784616158-git-send-email->
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      d9a3da06
  20. 29 10月, 2009 1 次提交
  21. 26 10月, 2009 1 次提交