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charset="utf-8" For RT class,=20 - During wakeup don't select a paravirt CPU. - Don't pull a task towards a paravirt CPU. - Don't push a task to a paravirt CPU. Signed-off-by: Shrikanth Hegde --- kernel/sched/rt.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 7936d4333731..54bfac66624b 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1552,6 +1552,9 @@ select_task_rq_rt(struct task_struct *p, int cpu, int= flags) if (!test && target !=3D -1 && !rt_task_fits_capacity(p, target)) goto out_unlock; =20 + /* Avoid moving to a paravirt CPU */ + if (is_cpu_paravirt(target)) + goto out_unlock; /* * Don't bother moving it if the destination CPU is * not running a lower priority task. @@ -1876,7 +1879,7 @@ static struct rq *find_lock_lowest_rq(struct task_str= uct *task, struct rq *rq) for (tries =3D 0; tries < RT_MAX_TRIES; tries++) { cpu =3D find_lowest_rq(task); =20 - if ((cpu =3D=3D -1) || (cpu =3D=3D rq->cpu)) + if ((cpu =3D=3D -1) || (cpu =3D=3D rq->cpu) || is_cpu_paravirt(cpu)) break; =20 lowest_rq =3D cpu_rq(cpu); @@ -1974,7 +1977,7 @@ static int push_rt_task(struct rq *rq, bool pull) return 0; =20 cpu =3D find_lowest_rq(rq->curr); - if (cpu =3D=3D -1 || cpu =3D=3D rq->cpu) + if (cpu =3D=3D -1 || cpu =3D=3D rq->cpu || is_cpu_paravirt(cpu)) return 0; =20 /* @@ -2237,6 +2240,10 @@ static void pull_rt_task(struct rq *this_rq) if (likely(!rt_overload_count)) return; =20 + /* There is no point in pulling the task towards a paravirt cpu */ + if (is_cpu_paravirt(this_rq->cpu)) + return; + /* * Match the barrier from rt_set_overloaded; this guarantees that if we * see overloaded we must also see the rto_mask bit. --=20 2.47.3