Messages in this thread Patch in this message | | | Date | Wed, 20 Jan 2010 20:15:50 -0800 | From | Greg KH <> | Subject | [29/30] sched: Fix task priority bug |
| |
2.6.32-stable review patch. If anyone has any objections, please let us know.
------------------
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
commit 57785df5ac53c70da9fb53696130f3c551bfe1f9 upstream.
83f9ac removed a call to effective_prio() in wake_up_new_task(), which leads to tasks running at MAX_PRIO.
This is caused by the idle thread being set to MAX_PRIO before forking off init. O(1) used that to make sure idle was always preempted, CFS uses check_preempt_curr_idle() for that so we can savely remove this bit of legacy code.
Reported-by: Mike Galbraith <efault@gmx.de> Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <1259754383.4003.610.camel@laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- kernel/sched.c | 6 ------ 1 file changed, 6 deletions(-)
--- a/kernel/sched.c +++ b/kernel/sched.c @@ -3177,10 +3177,6 @@ static void pull_task(struct rq *src_rq, deactivate_task(src_rq, p, 0); set_task_cpu(p, this_cpu); activate_task(this_rq, p, 0); - /* - * Note that idle threads have a prio of MAX_PRIO, for this test - * to be always true for them. - */ check_preempt_curr(this_rq, p, 0); } @@ -6982,7 +6978,6 @@ void __cpuinit init_idle(struct task_str __sched_fork(idle); idle->se.exec_start = sched_clock(); - idle->prio = idle->normal_prio = MAX_PRIO; cpumask_copy(&idle->cpus_allowed, cpumask_of(cpu)); __set_task_cpu(idle, cpu); @@ -7686,7 +7681,6 @@ migration_call(struct notifier_block *nf spin_lock_irq(&rq->lock); update_rq_clock(rq); deactivate_task(rq, rq->idle, 0); - rq->idle->static_prio = MAX_PRIO; __setscheduler(rq, rq->idle, SCHED_NORMAL, 0); rq->idle->sched_class = &idle_sched_class; migrate_dead_tasks(cpu);
| |