From b7d6f8f22bfe5e178b299cf25a33dece11b11054 Mon Sep 17 00:00:00 2001 From: Olav Haugan Date: Wed, 5 Aug 2015 08:45:21 -0700 Subject: [PATCH] sched: Update task->on_rq when tasks are moving between runqueues Task->on_rq has three states: 0 - Task is not on runqueue (rq) 1 (TASK_ON_RQ_QUEUED) - Task is on rq 2 (TASK_ON_RQ_MIGRATING) - Task is on rq but in the process of being migrated to another rq When a task is moving between rqs task->on_rq state should be TASK_ON_RQ_MIGRATING in order for WALT to account rq's cumulative runnable average correctly. Without such state marking for all the classes, WALT's update_history() would try to fixup task's demand which was never contributed to any of CPUs during migration. Change-Id: Iced3428f3924fe8ab5d0075698273ead04f12d5b Signed-off-by: Olav Haugan [joonwoop: Reinforced changelog to explain why this is needed by WALT. Fixed conflicts in deadline.c] Signed-off-by: Joonwoo Park --- kernel/sched/core.c | 2 ++ kernel/sched/deadline.c | 4 ++++ kernel/sched/rt.c | 4 ++++ 3 files changed, 10 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index fb6076ca98d2..5e7f755b4a21 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1331,7 +1331,9 @@ static void __migrate_swap_task(struct task_struct *p, int cpu) dst_rq = cpu_rq(cpu); deactivate_task(src_rq, p, 0); + p->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(p, cpu); + p->on_rq = TASK_ON_RQ_QUEUED; activate_task(dst_rq, p, 0); check_preempt_curr(dst_rq, p, 0); } else { diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 2aae8b8b68e8..ab1a9a99660d 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1587,7 +1587,9 @@ static int push_dl_task(struct rq *rq) deactivate_task(rq, next_task, 0); clear_average_bw(&next_task->dl, &rq->dl); + next_task->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(next_task, later_rq->cpu); + next_task->on_rq = TASK_ON_RQ_QUEUED; add_average_bw(&next_task->dl, &later_rq->dl); activate_task(later_rq, next_task, 0); ret = 1; @@ -1677,7 +1679,9 @@ static void pull_dl_task(struct rq *this_rq) deactivate_task(src_rq, p, 0); clear_average_bw(&p->dl, &src_rq->dl); + p->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(p, this_cpu); + p->on_rq = TASK_ON_RQ_QUEUED; add_average_bw(&p->dl, &this_rq->dl); activate_task(this_rq, p, 0); dmin = p->dl.deadline; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 6bb51d62dca4..3715473fd8f8 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1882,7 +1882,9 @@ static int push_rt_task(struct rq *rq) } deactivate_task(rq, next_task, 0); + next_task->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(next_task, lowest_rq->cpu); + next_task->on_rq = TASK_ON_RQ_QUEUED; activate_task(lowest_rq, next_task, 0); ret = 1; @@ -2136,7 +2138,9 @@ static void pull_rt_task(struct rq *this_rq) resched = true; deactivate_task(src_rq, p, 0); + p->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(p, this_cpu); + p->on_rq = TASK_ON_RQ_QUEUED; activate_task(this_rq, p, 0); /* * We continue with the search, just in