redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

sched/fair: Consolidate nohz CPU load update code 

Lets factorize a bit of code there. We'll even have a third user soon.
While at it, standardize the idle update function name against the
others.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Byungchul Park <byungchul.park@lge.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1452700891-21807-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
hifive-unleashed-5.1
Frederic Weisbecker 2016-01-13 17:01:29 +01:00 committed by Ingo Molnar
parent 7400d3bbaa
commit be68a682c0
1 changed files with 25 additions and 23 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
kernel/sched/fair.c
View File

@ -4542,6 +4542,25 @@ static unsigned long weighted_cpuload(const int cpu)
}
#ifdef CONFIG_NO_HZ_COMMON
static void __update_cpu_load_nohz(struct rq *this_rq,
unsigned long curr_jiffies,
unsigned long load,
int active)
{
unsigned long pending_updates;
pending_updates = curr_jiffies - this_rq->last_load_update_tick;
if (pending_updates) {
this_rq->last_load_update_tick = curr_jiffies;
/*
* In the regular NOHZ case, we were idle, this means load 0.
* In the NOHZ_FULL case, we were non-idle, we should consider
* its weighted load.
*/
__update_cpu_load(this_rq, load, pending_updates, active);
}
}
/*
* There is no sane way to deal with nohz on smp when using jiffies because the
* cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
@ -4559,22 +4578,15 @@ static unsigned long weighted_cpuload(const int cpu)
* Called from nohz_idle_balance() to update the load ratings before doing the
* idle balance.
*/
static void update_idle_cpu_load(struct rq *this_rq)
static void update_cpu_load_idle(struct rq *this_rq)
{
unsigned long curr_jiffies = READ_ONCE(jiffies);
unsigned long load = weighted_cpuload(cpu_of(this_rq));
unsigned long pending_updates;
/*
* bail if there's load or we're actually up-to-date.
*/
if (load || curr_jiffies == this_rq->last_load_update_tick)
if (weighted_cpuload(cpu_of(this_rq)))
return;
pending_updates = curr_jiffies - this_rq->last_load_update_tick;
this_rq->last_load_update_tick = curr_jiffies;
__update_cpu_load(this_rq, load, pending_updates, 0);
__update_cpu_load_nohz(this_rq, READ_ONCE(jiffies), 0, 0);
}
/*
@ -4585,22 +4597,12 @@ void update_cpu_load_nohz(int active)
struct rq *this_rq = this_rq();
unsigned long curr_jiffies = READ_ONCE(jiffies);
unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0;
unsigned long pending_updates;
if (curr_jiffies == this_rq->last_load_update_tick)
return;
raw_spin_lock(&this_rq->lock);
pending_updates = curr_jiffies - this_rq->last_load_update_tick;
if (pending_updates) {
this_rq->last_load_update_tick = curr_jiffies;
/*
* In the regular NOHZ case, we were idle, this means load 0.
* In the NOHZ_FULL case, we were non-idle, we should consider
* its weighted load.
*/
__update_cpu_load(this_rq, load, pending_updates, active);
}
__update_cpu_load_nohz(this_rq, curr_jiffies, load, active);
raw_spin_unlock(&this_rq->lock);
}
#endif /* CONFIG_NO_HZ */
@ -4612,7 +4614,7 @@ void update_cpu_load_active(struct rq *this_rq)
{
unsigned long load = weighted_cpuload(cpu_of(this_rq));
/*
* See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
* See the mess around update_cpu_load_idle() / update_cpu_load_nohz().
*/
this_rq->last_load_update_tick = jiffies;
__update_cpu_load(this_rq, load, 1, 1);
@ -7906,7 +7908,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle)
if (time_after_eq(jiffies, rq->next_balance)) {
raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
update_idle_cpu_load(rq);
update_cpu_load_idle(rq);
raw_spin_unlock_irq(&rq->lock);
rebalance_domains(rq, CPU_IDLE);
}