Commit 05981277 authored May 12, 2015 by Paul E. McKenney Committed by Catalin Marinas May 21, 2015

arm64: Use common outgoing-CPU-notification code

This commit removes the open-coded CPU-offline notification with new
common code. In particular, this change avoids calling scheduler code
using RCU from an offline CPU that RCU is ignoring. This is a minimal
change. A more intrusive change might invoke the cpu_check_up_prepare()
and cpu_set_state_online() functions at CPU-online time, which would
allow onlining throw an error if the CPU did not go offline properly.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: linux-arm-kernel@lists.infradead.org
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

parent 5b09a094

arch/arm64/kernel/smp.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -254,15 +254,13 @@ static int op_cpu_kill(unsigned int cpu)
		return cpu_ops[cpu]->cpu_kill(cpu);
		}

		static DECLARE_COMPLETION(cpu_died);

		/*
		* called on the thread which is asking for a CPU to be shutdown -
		* waits until shutdown has completed, or it is timed out.
		*/
		void __cpu_die(unsigned int cpu)
		{
		if (!wait_for_completion_timeout(&cpu_died, msecs_to_jiffies(5000))) {
		if (!cpu_wait_death(cpu, 5)) {
		pr_crit("CPU%u: cpu didn't die\n", cpu);
		return;
		}
		@@ -295,7 +293,7 @@ void cpu_die(void)
		local_irq_disable();

		/* Tell __cpu_die() that this CPU is now safe to dispose of */
		complete(&cpu_died);
		(void)cpu_report_death();

		/*
		* Actually shutdown the CPU. This must never fail. The specific hotplug