sched: EAS/WALT: take into account of waking task's load
WALT's function cpu_util(cpu) reports CPU's load without taking into
account of waking task's load. Thus currently cpu_overutilized()
underestimates load on the previous CPU of waking task.
Take into account of task's load to determine whether previous CPU is
overutilzed to bail out early without running energy_diff() which is
expensive.
Change-Id: I30f146984a880ad2cc1b8a4ce35bd239a8c9a607
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>
(minor rebase conflicts)
Signed-off-by: Chris Redpath <chris.redpath@arm.com>
(cherry picked from commit 94e5c965075b55a5dfd1c4cce580e2dfb0c7ffc3)
[trivial cherry-pick issues]
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index db5d684..7f42743 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -4786,6 +4786,7 @@
#endif
#ifdef CONFIG_SMP
+static bool __cpu_overutilized(int cpu, int delta);
static bool cpu_overutilized(int cpu);
unsigned long boosted_cpu_util(int cpu);
#else
@@ -6025,9 +6026,14 @@
return __task_fits(p, cpu, 0);
}
+static bool __cpu_overutilized(int cpu, int delta)
+{
+ return (capacity_of(cpu) * 1024) < ((cpu_util(cpu) + delta) * capacity_margin);
+}
+
static bool cpu_overutilized(int cpu)
{
- return (capacity_of(cpu) * 1024) < (cpu_util(cpu) * capacity_margin);
+ return __cpu_overutilized(cpu, 0);
}
#ifdef CONFIG_SCHED_TUNE
@@ -7032,6 +7038,7 @@
}
if (target_cpu != prev_cpu) {
+ int delta = 0;
struct energy_env eenv = {
.util_delta = task_util(p),
.src_cpu = prev_cpu,
@@ -7040,8 +7047,13 @@
.trg_cpu = target_cpu,
};
+
+#ifdef CONFIG_SCHED_WALT
+ if (!walt_disabled && sysctl_sched_use_walt_cpu_util)
+ delta = task_util(p);
+#endif
/* Not enough spare capacity on previous cpu */
- if (cpu_overutilized(prev_cpu)) {
+ if (__cpu_overutilized(prev_cpu, delta)) {
schedstat_inc(p->se.statistics.nr_wakeups_secb_insuff_cap);
schedstat_inc(this_rq()->eas_stats.secb_insuff_cap);
goto unlock;