MIPS: Use common outgoing-CPU-notification code

Replace the open-coded CPU-offline notification with common code.
In particular avoid calling scheduler code using RCU from an offline CPU
that RCU is ignoring.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15921/
Patchwork: https://patchwork.linux-mips.org/patch/15953/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/smp-cps.c

@@ -8,6 +8,7 @@
  * option) any later version.
  */
 
+#include <linux/cpu.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/irqchip/mips-gic.h>
@@ -408,7 +409,6 @@ static int cps_cpu_disable(void)
 	return 0;
 }
 
-static DECLARE_COMPLETION(cpu_death_chosen);
 static unsigned cpu_death_sibling;
 static enum {
 	CPU_DEATH_HALT,
@@ -444,7 +444,7 @@ void play_dead(void)
 	}
 
 	/* This CPU has chosen its way out */
-	complete(&cpu_death_chosen);
+	(void)cpu_report_death();
 
 	if (cpu_death == CPU_DEATH_HALT) {
 		vpe_id = cpu_vpe_id(&cpu_data[cpu]);
@@ -493,8 +493,7 @@ static void cps_cpu_die(unsigned int cpu)
 	int err;
 
 	/* Wait for the cpu to choose its way out */
-	if (!wait_for_completion_timeout(&cpu_death_chosen,
-					 msecs_to_jiffies(5000))) {
+	if (!cpu_wait_death(cpu, 5)) {
 		pr_err("CPU%u: didn't offline\n", cpu);
 		return;
 	}