diff options
| author | Olav Haugan <ohaugan@codeaurora.org> | 2015-03-03 16:55:56 -0800 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-23 20:01:57 -0700 |
| commit | 6e08a8c77afc2bca795b96af124cc23eab1633ea (patch) | |
| tree | 21f48109d40081735a1873e7a88968064bfb67ae /kernel | |
| parent | 652e8bc905e20d43d35f13403c89a6589b9d5866 (diff) | |
sched/fair: Add irq load awareness to the tick CPU selection logic
IRQ load is not taken into account when determining whether a task
should be migrated to a different CPU. A task that runs for a long time
could get stuck on CPU with high IRQ load causing degraded performance.
Add irq load awareness to the tick CPU selection logic.
CRs-fixed: 809119
Change-Id: I7969f7dd947fb5d66fce0bedbc212bfb2d42c8c1
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/fair.c | 28 |
1 files changed, 18 insertions, 10 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6da8a188ee30..868211061673 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3334,9 +3334,10 @@ static int best_small_task_cpu(struct task_struct *p, int sync) return best_fallback_cpu; } -#define MOVE_TO_BIG_CPU 1 -#define MOVE_TO_LITTLE_CPU 2 -#define MOVE_TO_POWER_EFFICIENT_CPU 3 +#define UP_MIGRATION 1 +#define DOWN_MIGRATION 2 +#define EA_MIGRATION 3 +#define IRQLOAD_MIGRATION 4 static int skip_cpu(struct task_struct *p, int cpu, int reason) { @@ -3351,18 +3352,22 @@ static int skip_cpu(struct task_struct *p, int cpu, int reason) return 1; switch (reason) { - case MOVE_TO_BIG_CPU: + case UP_MIGRATION: skip = (rq->capacity <= task_rq->capacity); break; - case MOVE_TO_LITTLE_CPU: + case DOWN_MIGRATION: skip = (rq->capacity >= task_rq->capacity); break; - case MOVE_TO_POWER_EFFICIENT_CPU: + case EA_MIGRATION: skip = rq->capacity < task_rq->capacity || power_cost(p, cpu) > power_cost(p, task_cpu(p)); break; + + case IRQLOAD_MIGRATION: + /* Purposely fall through */ + default: skip = (cpu == task_cpu(p)); break; @@ -4133,7 +4138,7 @@ static inline int migration_needed(struct rq *rq, struct task_struct *p) if (sched_boost()) { if (rq->capacity != max_capacity) - return MOVE_TO_BIG_CPU; + return UP_MIGRATION; return 0; } @@ -4141,18 +4146,21 @@ static inline int migration_needed(struct rq *rq, struct task_struct *p) if (is_small_task(p)) return 0; + if (sched_cpu_high_irqload(cpu_of(rq))) + return IRQLOAD_MIGRATION; + if ((nice > sched_upmigrate_min_nice || upmigrate_discouraged(p)) && rq->capacity > min_capacity) - return MOVE_TO_LITTLE_CPU; + return DOWN_MIGRATION; if (!task_will_fit(p, cpu_of(rq))) - return MOVE_TO_BIG_CPU; + return UP_MIGRATION; if (sysctl_sched_enable_power_aware && !is_task_migration_throttled(p) && is_cpu_throttling_imminent(cpu_of(rq)) && lower_power_cpu_available(p, cpu_of(rq))) - return MOVE_TO_POWER_EFFICIENT_CPU; + return EA_MIGRATION; return 0; } |