printk: nbcon: Assign nice -20 for printing threads

It is important that console printing threads are scheduled
shortly after a printk call and with generous runtime budgets.

Signed-off-by: John Ogness <[email protected]>
Reviewed-by: Petr Mladek <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Petr Mladek <[email protected]>

Author: jogness

kernel/printk/nbcon.c

@@ -1321,6 +1321,12 @@ bool nbcon_kthread_create(struct console *con)
 
 	con->kthread = kt;
 
+	/*
+	 * It is important that console printing threads are scheduled
+	 * shortly after a printk call and with generous runtime budgets.
+	 */
+	sched_set_normal(con->kthread, -20);
+
 	return true;
 }
 

kernel/printk/printk.c

@@ -3555,6 +3555,12 @@ static bool legacy_kthread_create(void)
 
 	printk_legacy_kthread = kt;
 
+	/*
+	 * It is important that console printing threads are scheduled
+	 * shortly after a printk call and with generous runtime budgets.
+	 */
+	sched_set_normal(printk_legacy_kthread, -20);
+
 	return true;
 }