linux-kernel - [PATCH 02/23] sched,bL_switcher: Convert to sched_set

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Date:   Wed, 22 Apr 2020 13:27:21 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     mingo@...nel.org, linux-kernel@...r.kernel.org
Cc:     tglx@...utronix.de, rostedt@...dmis.org, qais.yousef@....com,
        juri.lelli@...hat.com, vincent.guittot@...aro.org,
        dietmar.eggemann@....com, bsegall@...gle.com, mgorman@...e.de,
        peterz@...radead.org, nico@...xnic.net, rmk+kernel@....linux.org.uk
Subject: [PATCH 02/23] sched,bL_switcher: Convert to sched_set_fifo*()

Because SCHED_FIFO is a broken scheduler model (see previous patches)
take away the priority field, the kernel can't possibly make an
informed decision.

In this case, use fifo_low, because it only cares about being above
SCHED_NORMAL. Effectively no change in behaviour.

Cc: nico@...xnic.net
Cc: rmk+kernel@....linux.org.uk
Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Reviewed-by: Ingo Molnar <mingo@...nel.org>
---
 arch/arm/common/bL_switcher.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/arch/arm/common/bL_switcher.c
+++ b/arch/arm/common/bL_switcher.c
@@ -270,12 +270,11 @@ static struct bL_thread bL_threads[NR_CP
 static int bL_switcher_thread(void *arg)
 {
 	struct bL_thread *t = arg;
-	struct sched_param param = { .sched_priority = 1 };
 	int cluster;
 	bL_switch_completion_handler completer;
 	void *completer_cookie;
 
-	sched_setscheduler_nocheck(current, SCHED_FIFO, &param);
+	sched_set_fifo_low(current);
 	complete(&t->started);
 
 	do {