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* sched: group scheduler, fix latencySrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | | | | | There is a possibility that because of task of a group moving from one cpu to another, it may gain more cpu time that desired. See http://marc.info/?l=linux-kernel&m=119073197730334 for details. This is an attempt to fix that problem. Basically it simulates dequeue of higher level entities as if they are going to sleep. Similarly it simulate wakeup of higher level entities as if they are waking up from sleep. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: group scheduler, fix bloatSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | | | | Recent fix to check_preempt_wakeup() to check for preemption at higher levels caused a size bloat for !CONFIG_FAIR_GROUP_SCHED. Fix the problem. 42277 10598 320 53195 cfcb kernel/sched.o-before_this_patch 42216 10598 320 53134 cf8e kernel/sched.o-after_this_patch Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: group scheduler, fix coding style issuesSrivatsa Vaddagiri2007-10-15
| | | | | | | | | Fix coding style issues reported by Randy Dunlap and others Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: cleanup, remove stale commentIngo Molnar2007-10-15
| | | | | | | cleanup, remove stale comment. Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: speed up and simplify vslice calculationsPeter Zijlstra2007-10-15
| | | | | | | | | speed up and simplify vslice calculations. [ From: Mike Galbraith <efault@gmx.de>: build fix ] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: clean up min_vruntime usePeter Zijlstra2007-10-15
| | | | | | | clean up min_vruntime use. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: group scheduler SMP migration fixSrivatsa Vaddagiri2007-10-15
| | | | | | | | group scheduler SMP migration fix: use task_cfs_rq(p) to get to the relevant fair-scheduling runqueue of a task, rq->cfs is not the right one. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: clean up schedstats, cnt -> countIngo Molnar2007-10-15
| | | | | | | | | | | | | | | | rename all 'cnt' fields and variables to the less yucky 'count' name. yuckage noticed by Andrew Morton. no change in code, other than the /proc/sched_debug bkl_count string got a bit larger: text data bss dec hex filename 38236 3506 24 41766 a326 sched.o.before 38240 3506 24 41770 a32a sched.o.after Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: yield fixDmitry Adamushko2007-10-15
| | | | | | | | | | | | | | | | | | fix yield bugs due to the current-not-in-rbtree changes: the task is not in the rbtree so rbtree-removal is a no-no. [ From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>: build fix. ] also, nice code size reduction: kernel/sched.o: text data bss dec hex filename 38323 3506 24 41853 a37d sched.o.before 38236 3506 24 41766 a326 sched.o.after Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: group scheduler wakeup latency fixSrivatsa Vaddagiri2007-10-15
| | | | | | | group scheduler wakeup latency fix: when checking for preemption we must check cross-group too, not just intra-group. Signed-off-by: Ingo Molnar <mingo@elte.hu>
* sched: remove set_leftmost()Ingo Molnar2007-10-15
| | | | | | | | | Lee Schermerhorn noticed that set_leftmost() contains dead code, remove this. Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: clean up sched_fork()Hiroshi Shimamoto2007-10-15
| | | | | | | | | | | | | | | | | | The adjusting sched_class is a missing part of the already existing "do not leak PI boosting priority to the child" at the sched_fork(). This patch moves the adjusting sched_class from wake_up_new_task() to sched_fork(). this also shrinks the code a bit: text data bss dec hex filename 40111 4018 292 44421 ad85 sched.o.before 40102 4018 292 44412 ad7c sched.o.after Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com> Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: max_vruntime() simplificationPeter Zijlstra2007-10-15
| | | | | | | max_vruntime() simplification. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: fix sched_fork()Ingo Molnar2007-10-15
| | | | | | | | | | fix sched_fork(): large latencies at new task creation time because the ->vruntime was not fixed up cross-CPU, if the parent got migrated after the child's CPU got set up. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: fix sign check error in place_entity()Ingo Molnar2007-10-15
| | | | | | | | fix sign check error in place_entity() - we'd get excessive latencies due to negatives being converted to large u64's. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: undo some of the recent changesIngo Molnar2007-10-15
| | | | | | | | undo some of the recent changes that are not needed after all, such as last_min_vruntime. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: remove last_min_vruntime effectIngo Molnar2007-10-15
| | | | | | | remove last_min_vruntime use - prepare to remove it. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: remove condition from set_task_cpu()Ingo Molnar2007-10-15
| | | | | | | | | remove condition from set_task_cpu(). Now that ->vruntime is not global anymore, it should (and does) work fine without it too. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: entity_key() fixIngo Molnar2007-10-15
| | | | | | | | entity_key() fix - we'd occasionally end up with a 0 vruntime in the !initial case. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched debug: check spreadPeter Zijlstra2007-10-15
| | | | | | | | | | debug feature: check how well we schedule within a reasonable vruntime 'spread' range. (note that CPU overload can increase the spread, so this is not a hard condition, but normal loads should be within the spread.) Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched debug: more width for parameter printoutsIngo Molnar2007-10-15
| | | | | | | | more width for parameter printouts in /proc/sched_debug. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: add vslicePeter Zijlstra2007-10-15
| | | | | | | | | | add vslice: the load-dependent "virtual slice" a task should run ideally, so that the observed latency stays within the sched_latency window. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched debug: print settingsIngo Molnar2007-10-15
| | | | | | | | print the current value of all tunables in /proc/sched_debug output. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: remove unneeded tunablesIngo Molnar2007-10-15
| | | | | | | | remove unneeded tunables. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched debug: BKL usage statistics, fixS.Caglar Onur2007-10-15
| | | | | | | | build fix for the SCHED_DEBUG && !SCHEDSTATS case. Signed-off-by: S.Ceglar Onur <caglar@pardus.org.tr> Signed-off-by: Ingo Molnar <mingo@elte.hu> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched debug: BKL usage statisticsIngo Molnar2007-10-15
| | | | | | | | add per task and per rq BKL usage statistics. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: add fair-user schedulerSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | | | | | | | | | Enable user-id based fair group scheduling. This is useful for anyone who wants to test the group scheduler w/o having to enable CONFIG_CGROUPS. A separate scheduling group (i.e struct task_grp) is automatically created for every new user added to the system. Upon uid change for a task, it is made to move to the corresponding scheduling group. A /proc tunable (/proc/root_user_share) is also provided to tune root user's quota of cpu bandwidth. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: clean up code under CONFIG_FAIR_GROUP_SCHEDSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | | | | | | With the view of supporting user-id based fair scheduling (and not just container-based fair scheduling), this patch renames several functions and makes them independent of whether they are being used for container or user-id based fair scheduling. Also fix a problem reported by KAMEZAWA Hiroyuki (wrt allocating less-sized array for tg->cfs_rq[] and tf->se[]). Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: print &rq->cfs statsSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | - Print &rq->cfs statistics as well (useful for group scheduling) Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: print nr_running and load in /proc/sched_debugSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | - print nr_running and load information for cfs_rq in /proc/sched_debug Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: fix minor bug in yieldSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | - fix a minor bug in yield (seen for CONFIG_FAIR_GROUP_SCHED), group scheduling would skew when yield was called. Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: revert recent removal of set_curr_task()Srivatsa Vaddagiri2007-10-15
| | | | | | | | | | Revert removal of set_curr_task. Use put_prev_task/set_curr_task when changing groups/policies Signed-off-by: Srivatsa Vaddagiri < vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: kernel/sched_fair.c whitespace cleanupsIngo Molnar2007-10-15
| | | | | | | | some trivial whitespace cleanups. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: fix formatting of /proc/sched_debugMike Galbraith2007-10-15
| | | | | | | | fix formatting of /proc/sched_debug Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: enhance debug outputIngo Molnar2007-10-15
| | | | | | | | | enhance debug output by changing 12345678 nsecs to 12.345678 output, this is more human-readable. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: prettify /proc/sched_debug outputIngo Molnar2007-10-15
| | | | | | | | print the correct amount of dashes in /proc/sched_debug. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: rework enqueue/dequeue_entity() to get rid of set_curr_task()Dmitry Adamushko2007-10-15
| | | | | | | | | | | | | | | | rework enqueue/dequeue_entity() to get rid of sched_class::set_curr_task(). This simplifies sched_setscheduler(), rt_mutex_setprio() and sched_move_tasks(). text data bss dec hex filename 24330 2734 20 27084 69cc sched.o.before 24233 2730 20 26983 6967 sched.o.after Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: simplify sched_class::yield_task()Dmitry Adamushko2007-10-15
| | | | | | | | | | | | | | the 'p' (task_struct) parameter in the sched_class :: yield_task() is redundant as the caller is always the 'current'. Get rid of it. text data bss dec hex filename 24341 2734 20 27095 69d7 sched.o.before 24330 2734 20 27084 69cc sched.o.after Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: optimize task_new_fair()Dmitry Adamushko2007-10-15
| | | | | | | | | | | | | | | | | due to the fact that we no longer keep the 'current' within the tree, dequeue/enqueue_entity() is useless for the 'current' in task_new_fair(). We are about to reschedule and sched_class->put_prev_task() will put the 'current' back into the tree, based on its new key. text data bss dec hex filename 24388 2734 20 27142 6a06 sched.o.before 24341 2734 20 27095 69d7 sched.o.after Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: fix delay accounting performance regressionIngo Molnar2007-10-15
| | | | | | | | | fix delay accounting performance regression - those sched_clock() calls are not needed. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: do not keep current in the tree and get rid of sched_entity::fair_keyDmitry Adamushko2007-10-15
| | | | | | | | | | | | | | | Get rid of 'sched_entity::fair_key'. As a side effect, 'current' is not kept withing the tree for SCHED_NORMAL/BATCH tasks anymore. This simplifies some parts of code (e.g. entity_tick() and yield_task_fair()) and also somewhat optimizes them (e.g. a single update_curr() now vs. dequeue/enqueue() before in entity_tick()). Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: add set_curr_task() callsDmitry Adamushko2007-10-15
| | | | | | | | | | | | | p->sched_class->set_curr_task() has to be called before activate_task()/enqueue_task() in rt_mutex_setprio(), sched_setschedule() and sched_move_task() in order to set up 'cfs_rq->curr'. The logic of enqueueing depends on whether a task to be inserted is 'current' or not. Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: sched_setscheduler() fixDmitry Adamushko2007-10-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a problem in the 'sched-group' patch for !CONFIG_FAIR_GROUP_SCHED. description: sched_setscheduler() { ... if (task_running()) p->sched_class->put_prev_entity(); [ this one sets up cfs_rq->curr to NULL ] ... if (task_running) p->sched_class->set_curr_task(); [ and this one is a _NOP_ (empty) for !CONFIG_FAIR_GROUP_SCHED ] As a result, the task continues to run with cfs_rq->curr == NULL... no crashes (due to checks for !NULL in place) but e.g. update_curr() effectively becomes a NOP... i.e. runtime statistics for this task is not accounted untill it's rescheduled anew. Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: group-scheduler coreSrivatsa Vaddagiri2007-10-15
| | | | | | | | | | | Add interface to control cpu bandwidth allocation to task-groups. (not yet configurable, due to missing CONFIG_CONTAINERS) Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
* sched: fix SMP migration latenciesMike Galbraith2007-10-15
| | | | | | | | | | | fix SMP migration latencies: the vruntimes of different CPUs are at incompatible offsets so they have to be fixed up when migrating a task across CPUs. Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: better min_vruntime trackingPeter Zijlstra2007-10-15
| | | | | | | | | | Better min_vruntime tracking: update it every time 'curr' is updated - not just when a task is enqueued into the tree. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Mike Galbraith <efault@gmx.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: clean up schedstat block in dequeue_entity()Dmitry Adamushko2007-10-15
| | | | | | | | | | Better placement of #ifdef CONFIG_SCHEDSTAT block in dequeue_entity(). Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: remove wait_runtime fields and featuresIngo Molnar2007-10-15
| | | | | | | | | | remove wait_runtime based fields and features, now that the CFS math has been changed over to the vruntime metric. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mike Galbraith <efault@gmx.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: remove wait_runtime limitIngo Molnar2007-10-15
| | | | | | | | | | remove the wait_runtime-limit fields and the code depending on it, now that the math has been changed over to rely on the vruntime metric. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mike Galbraith <efault@gmx.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
* sched: clean up struct load_statDmitry Adamushko2007-10-15
| | | | | | | | | | 'struct load_stat' is redundant now so let's get rid of it. Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mike Galbraith <efault@gmx.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>