linux/kernel/sched
Kirill Tkhai f3a7e1a9c4 sched/dl: Fix preemption checks
1) switched_to_dl() check is wrong. We reschedule only
   if rq->curr is deadline task, and we do not reschedule
   if it's a lower priority task. But we must always
   preempt a task of other classes.

2) dl_task_timer():
   Policy does not change in case of priority inheritance.
   rt_mutex_setprio() changes prio, while policy remains old.

So we lose some balancing logic in dl_task_timer() and
switched_to_dl() when we check policy instead of priority. Boosted
task may be rq->curr.

(I didn't change switched_from_dl() because no check is necessary
there at all).

I've looked at this place(switched_to_dl) several times and even fixed
this function, but found just now...  I suppose some performance tests
may work better after this.

Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1413909356.19914.128.camel@tkhai
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-28 10:46:10 +01:00
..
auto_group.c sched: Change autogroup_move_group() to use for_each_thread() 2014-08-20 09:47:18 +02:00
auto_group.h
clock.c time: Replace __get_cpu_var uses 2014-08-26 13:45:44 -04:00
completion.c sched: Move completion code from core.c to completion.c 2013-11-06 07:49:19 +01:00
core.c sched: stop the unbound recursion in preempt_schedule_context() 2014-10-28 10:46:05 +01:00
cpuacct.c cgroup: rename cgroup_subsys->base_cftypes to ->legacy_cftypes 2014-07-15 11:05:09 -04:00
cpuacct.h sched/cpuacct: Initialize root cpuacct earlier 2013-04-10 13:54:20 +02:00
cpudeadline.c sched/deadline: Fix inter- exclusive cpusets migrations 2014-09-24 14:46:57 +02:00
cpudeadline.h sched/deadline: Replace NR_CPUS arrays 2014-05-22 10:21:28 +02:00
cpupri.c Merge commit '3cf2f34' into sched/core, to fix build error 2014-06-12 13:46:37 +02:00
cpupri.h sched/cpupri: Replace NR_CPUS arrays 2014-05-22 10:21:29 +02:00
cputime.c sched, time: Fix build error with 64 bit cputime_t on 32 bit systems 2014-10-03 05:46:55 +02:00
deadline.c sched/dl: Fix preemption checks 2014-10-28 10:46:10 +01:00
debug.c sched: print_rq(): Don't use tasklist_lock 2014-09-24 14:47:04 +02:00
fair.c sched/fair: Fix division by zero sysctl_numa_balancing_scan_size 2014-10-28 10:46:04 +01:00
features.h sched: Rename capacity related flags 2014-06-05 11:52:32 +02:00
idle_task.c sched: Transform resched_task() into resched_curr() 2014-07-16 13:38:19 +02:00
idle.c sched: Let the scheduler see CPU idle states 2014-09-24 14:46:58 +02:00
Makefile sched/idle: Move cpu/idle.c to sched/idle.c 2014-02-11 09:58:30 +01:00
proc.c cpuidle: menu: Lookup CPU runqueues less 2014-08-06 21:17:45 +02:00
rt.c Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2014-10-15 07:48:18 +02:00
sched.h Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu 2014-10-15 07:48:18 +02:00
stats.c kernel: audit/fix non-modular users of module_init in core code 2014-04-03 16:21:07 -07:00
stats.h sched: Micro-optimize by dropping unnecessary task_rq() calls 2013-09-25 13:51:06 +02:00
stop_task.c sched: Add wrapper for checking task_struct::on_rq 2014-08-20 14:52:59 +02:00
wait.c SCHED: add some "wait..on_bit...timeout()" interfaces. 2014-09-25 08:23:57 -04:00