Commit e5355cd6 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Thomas Gleixner
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sparc/sysfs: Convert to hotplug state machine 



Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

The previous convention of keeping the files around until the CPU is dead
has not been preserved as there is no point to keep them available when the
cpu is going down. This makes the hotplug call symmetric.

Signed-off-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: default avatar"David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Cc: rt@linuxtronix.de
Link: http://lkml.kernel.org/r/20161117183541.8588-18-bigeasy@linutronix.de


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 977ab257

arch/sparc/kernel/sysfs.c

+9 −36
Original line number Diff line number Diff line
@@ -221,7 +221,7 @@ static struct device_attribute cpu_core_attrs[] = { 


static DEFINE_PER_CPU(struct cpu, cpu_devices);



static void register_cpu_online(unsigned int cpu)

static int register_cpu_online(unsigned int cpu)

{

	struct cpu *c = &per_cpu(cpu_devices, cpu);

	struct device *s = &c->dev;
@@ -231,11 +231,12 @@ static void register_cpu_online(unsigned int cpu) 
		device_create_file(s, &cpu_core_attrs[i]);



	register_mmu_stats(s);

	return 0;

}



#ifdef CONFIG_HOTPLUG_CPU

static void unregister_cpu_online(unsigned int cpu)

static int unregister_cpu_online(unsigned int cpu)

{

#ifdef CONFIG_HOTPLUG_CPU

	struct cpu *c = &per_cpu(cpu_devices, cpu);

	struct device *s = &c->dev;

	int i;
@@ -243,32 +244,9 @@ static void unregister_cpu_online(unsigned int cpu) 
	unregister_mmu_stats(s);

	for (i = 0; i < ARRAY_SIZE(cpu_core_attrs); i++)

		device_remove_file(s, &cpu_core_attrs[i]);

}

#endif



static int sysfs_cpu_notify(struct notifier_block *self,

				      unsigned long action, void *hcpu)

{

	unsigned int cpu = (unsigned int)(long)hcpu;



	switch (action) {

	case CPU_ONLINE:

	case CPU_ONLINE_FROZEN:

		register_cpu_online(cpu);

		break;

#ifdef CONFIG_HOTPLUG_CPU

	case CPU_DEAD:

	case CPU_DEAD_FROZEN:

		unregister_cpu_online(cpu);

		break;

#endif

	return 0;

}

	return NOTIFY_OK;

}



static struct notifier_block sysfs_cpu_nb = {

	.notifier_call	= sysfs_cpu_notify,

};



static void __init check_mmu_stats(void)

{
@@ -294,26 +272,21 @@ static void register_nodes(void) 


static int __init topology_init(void)

{

	int cpu;

	int cpu, ret;



	register_nodes();



	check_mmu_stats();



	cpu_notifier_register_begin();



	for_each_possible_cpu(cpu) {

		struct cpu *c = &per_cpu(cpu_devices, cpu);



		register_cpu(c, cpu);

		if (cpu_online(cpu))

			register_cpu_online(cpu);

	}



	__register_cpu_notifier(&sysfs_cpu_nb);



	cpu_notifier_register_done();



	ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "sparc/topology:online",

				register_cpu_online, unregister_cpu_online);

	WARN_ON(ret < 0);

	return 0;

}

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