remove the 'u64 now' parameter from dec_nr_running().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from inc_nr_running().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from dec_load().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from inc_load().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_curr_load().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from ->task_new().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from ->put_prev_task().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from pick_next_task().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from ->pick_next_task().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from ->dequeue_task().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from ->enqueue_task().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_curr_rt().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from put_prev_entity().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from pick_next_entity().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from set_next_entity().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from dequeue_entity().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from enqueue_entity().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from enqueue_sleeper().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from __enqueue_sleeper().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_curr_end().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_dequeue().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_curr_start().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_wait_end().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from __update_stats_wait_end().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_enqueue().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_stats_wait_start().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from update_curr().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the 'u64 now' parameter from print_cfs_rq().

( identity transformation that causes no change in functionality. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

change all 'now' timestamp uses in assignments to rq->clock.

( this is an identity transformation that causes no functionality change:
  all such new rq->clock is necessarily preceded by an update_rq_clock()
  call. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the (now unused) __rq_clock() function.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

eliminate __rq_clock() use by changing it to:

   __update_rq_clock(rq)
   now = rq->clock;

identity transformation - no change in behavior.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

remove the now unused rq_clock() function.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

eliminate rq_clock() use by changing it to:

   update_rq_clock(rq)
   now = rq->clock;

identity transformation - no change in behavior.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

add the [__]update_rq_clock(rq) functions. (No change in functionality,
just reorganization to prepare for elimination of the heavy 64-bit
timestamp-passing in the scheduler.)
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There are two problems with balance_tasks() and how it used:

1. The variables best_prio and best_prio_seen (inherited from the old
move_tasks()) were only required to handle problems caused by the
active/expired arrays, the order in which they were processed and the
possibility that the task with the highest priority could be on either.
  These issues are no longer present and the extra overhead associated
with their use is unnecessary (and possibly wrong).

2. In the absence of CONFIG_FAIR_GROUP_SCHED being set, the same
this_best_prio variable needs to be used by all scheduling classes or
there is a risk of moving too much load.  E.g. if the highest priority
task on this at the beginning is a fairly low priority task and the rt
class migrates a task (during its turn) then that moved task becomes the
new highest priority task on this_rq but when the sched_fair class
initializes its copy of this_best_prio it will get the priority of the
original highest priority task as, due to the run queue locks being
held, the reschedule triggered by pull_task() will not have taken place.
  This could result in inappropriate overriding of skip_for_load and
excessive load being moved.

The attached patch addresses these problems by deleting all reference to
best_prio and best_prio_seen and making this_best_prio a reference
parameter to the various functions involved.

load_balance_fair() has also been modified so that this_best_prio is
only reset (in the loop) if CONFIG_FAIR_GROUP_SCHED is set.  This should
preserve the effect of helping spread groups' higher priority tasks
around the available CPUs while improving system performance when
CONFIG_FAIR_GROUP_SCHED isn't set.
Signed-off-by: NPeter Williams <pwil3058@bigpond.net.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Document the design thinking behind nice levels.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel.sched_domain hierarchy is under CTL_UNNUMBERED and thus
unreachable to sysctl(2). Generating .ctl_number's in such situation is
not useful.
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

small delta_exec accounting fix: increase delta_exec and increase
sum_exec_runtime even if the task is not on the runqueue anymore.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

cleanup: delta_mine is an unsigned value.

no code impact:

   text    data     bss     dec     hex filename
   27823    2726      16   30565    7765 sched.o.before
   27823    2726      16   30565    7765 sched.o.after
Signed-off-by: NIngo Molnar <mingo@elte.hu>

speed up schedule(): share the 'now' parameter that deactivate_task()
was calculating internally.

( this also fixes the small accounting window between the deactivate
  call and the pick_next_task() call. )
Signed-off-by: NIngo Molnar <mingo@elte.hu>