From 77ba2b9f0be0eea3cc46186b7f4bd9ce7e7bd6df 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: I65e74a8f176c3ed4b8577577f6da8897ecda7bb8 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 (cherry picked from commit 0f8791c90a99f718c43ab8214076c0c671a36667) [fixed cherry-pick issue due to missing fab5cc59bf] Signed-off-by: Quentin Perret --- 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 1abd47a4f94b..daa2293d960e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1286,7 +1286,9 @@ static void __migrate_swap_task(struct task_struct *p, int cpu) p->on_rq = TASK_ON_RQ_MIGRATING; 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); p->on_rq = TASK_ON_RQ_QUEUED; check_preempt_curr(dst_rq, p, 0); diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 7d020665c71c..6c1f4443a150 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1505,7 +1505,9 @@ retry: } deactivate_task(rq, next_task, 0); + next_task->on_rq = TASK_ON_RQ_MIGRATING; set_task_cpu(next_task, later_rq->cpu); + next_task->on_rq = TASK_ON_RQ_QUEUED; activate_task(later_rq, next_task, 0); ret = 1; @@ -1593,7 +1595,9 @@ static void pull_dl_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); dmin = p->dl.deadline; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index c537c9dd0d94..559157eb36da 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1897,7 +1897,9 @@ retry: } 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; @@ -2151,7 +2153,9 @@ 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