From: Qais Yousef <qais.yousef@arm.com>
To: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Steven Rostedt <rostedt@goodmis.org>,
Dietmar Eggemann <dietmar.eggemann@arm.com>,
Pavan Kondeti <pkondeti@codeaurora.org>
Cc: Juri Lelli <juri.lelli@redhat.com>,
Vincent Guittot <vincent.guittot@linaro.org>,
Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
linux-kernel@vger.kernel.org, Qais Yousef <qais.yousef@arm.com>
Subject: [PATCH v3 4/6] sched/rt: Allow pulling unfitting task
Date: Mon, 2 Mar 2020 13:27:19 +0000 [thread overview]
Message-ID: <20200302132721.8353-5-qais.yousef@arm.com> (raw)
In-Reply-To: <20200302132721.8353-1-qais.yousef@arm.com>
When implemented RT Capacity Awareness; the logic was done such that if
a task was running on a fitting CPU, then it was sticky and we would try
our best to keep it there.
But as Steve suggested, to adhere to the strict priority rules of RT
class; allow pulling an RT task to unfitting CPU to ensure it gets a
chance to run ASAP.
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 804d402fb6f6 ("sched/rt: Make RT capacity-aware")
LINK: https://lore.kernel.org/lkml/20200203111451.0d1da58f@oasis.local.home/
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
---
kernel/sched/rt.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 3071c8612c03..e79a23ad4a93 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1656,8 +1656,7 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
{
if (!task_running(rq, p) &&
- cpumask_test_cpu(cpu, p->cpus_ptr) &&
- rt_task_fits_capacity(p, cpu))
+ cpumask_test_cpu(cpu, p->cpus_ptr))
return 1;
return 0;
--
2.17.1
next prev parent reply other threads:[~2020-03-02 13:27 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-02 13:27 [PATCH v3 0/6] RT Capacity Awareness Fixes & Improvements Qais Yousef
2020-03-02 13:27 ` [PATCH v3 1/6] sched/rt: cpupri_find: Implement fallback mechanism for !fit case Qais Yousef
[not found] ` <20200304143200.GA13200@geo.homenetwork>
2020-03-04 15:18 ` Qais Yousef
2020-03-04 16:27 ` Steven Rostedt
2020-03-04 17:39 ` Qais Yousef
2020-03-04 18:54 ` Steven Rostedt
2020-03-04 20:01 ` Qais Yousef
2020-03-05 12:43 ` Qais Yousef
2020-03-10 14:22 ` Qais Yousef
2020-03-11 13:51 ` Steven Rostedt
2020-03-20 12:58 ` [tip: sched/core] sched/rt: cpupri_find: Trigger a full search as fallback tip-bot2 for Qais Yousef
2020-03-06 14:42 ` [tip: sched/core] sched/rt: cpupri_find: Implement fallback mechanism for !fit case tip-bot2 for Qais Yousef
2020-03-02 13:27 ` [PATCH v3 2/6] sched/rt: Re-instate old behavior in select_task_rq_rt Qais Yousef
2020-03-06 14:42 ` [tip: sched/core] sched/rt: Re-instate old behavior in select_task_rq_rt() tip-bot2 for Qais Yousef
2020-03-02 13:27 ` [PATCH v3 3/6] sched/rt: Optimize cpupri_find on non-heterogenous systems Qais Yousef
2020-03-06 14:42 ` [tip: sched/core] sched/rt: Optimize cpupri_find() " tip-bot2 for Qais Yousef
2020-03-02 13:27 ` Qais Yousef [this message]
[not found] ` <20200304145219.GA14173@geo.homenetwork>
2020-03-04 15:28 ` [PATCH v3 4/6] sched/rt: Allow pulling unfitting task Qais Yousef
2020-03-06 14:42 ` [tip: sched/core] " tip-bot2 for Qais Yousef
2020-03-02 13:27 ` [PATCH v3 5/6] sched/rt: Remove unnecessary push for unfit tasks Qais Yousef
2020-03-06 14:42 ` [tip: sched/core] " tip-bot2 for Qais Yousef
2020-03-02 13:27 ` [PATCH v3 6/6] sched/rt: Fix pushing unfit tasks to a better CPU Qais Yousef
2020-03-06 17:51 ` Qais Yousef
2020-03-11 10:53 ` Pavan Kondeti
2020-03-11 14:11 ` Qais Yousef
2020-03-11 14:00 ` Steven Rostedt
2020-03-11 14:23 ` Qais Yousef
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