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Commit 455c017a authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Linus Torvalds
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microcode: use suspend-related CPU hotplug notifications 



Make the microcode driver use the suspend-related CPU hotplug notifications
to handle the CPU hotplug events occuring during system-wide suspend and
resume transitions.  Remove the global variable suspend_cpu_hotplug
previously used for this purpose.

Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8bb78442

arch/i386/kernel/microcode.c

+36 −26
Original line number Diff line number Diff line
@@ -567,7 +567,7 @@ static int cpu_request_microcode(int cpu) 
	return error;

}



static int apply_microcode_on_cpu(int cpu)

static int apply_microcode_check_cpu(int cpu)

{

	struct cpuinfo_x86 *c = cpu_data + cpu;

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
@@ -575,8 +575,9 @@ static int apply_microcode_on_cpu(int cpu) 
	unsigned int val[2];

	int err = 0;



	/* Check if the microcode is available */

	if (!uci->mc)

		return -EINVAL;

		return 0;



	old = current->cpus_allowed;

	set_cpus_allowed(current, cpumask_of_cpu(cpu));
@@ -614,7 +615,7 @@ static int apply_microcode_on_cpu(int cpu) 
	return err;

}



static void microcode_init_cpu(int cpu)

static void microcode_init_cpu(int cpu, int resume)

{

	cpumask_t old;

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
@@ -624,8 +625,7 @@ static void microcode_init_cpu(int cpu) 
	set_cpus_allowed(current, cpumask_of_cpu(cpu));

	mutex_lock(&microcode_mutex);

	collect_cpu_info(cpu);

	if (uci->valid && system_state == SYSTEM_RUNNING &&

	    !suspend_cpu_hotplug)

	if (uci->valid && system_state == SYSTEM_RUNNING && !resume)

		cpu_request_microcode(cpu);

	mutex_unlock(&microcode_mutex);

	set_cpus_allowed(current, old);
@@ -702,7 +702,7 @@ static struct attribute_group mc_attr_group = { 
	.name = "microcode",

};



static int mc_sysdev_add(struct sys_device *sys_dev)

static int __mc_sysdev_add(struct sys_device *sys_dev, int resume)

{

	int err, cpu = sys_dev->id;

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
@@ -711,38 +711,30 @@ static int mc_sysdev_add(struct sys_device *sys_dev) 
		return 0;



	pr_debug("Microcode:CPU %d added\n", cpu);

	/* If suspend_cpu_hotplug is set, the system is resuming and we should

	 * use the data from before the suspend.

	 */

	if (suspend_cpu_hotplug) {

		err = apply_microcode_on_cpu(cpu);

		if (err)

			microcode_fini_cpu(cpu);

	}

	if (!uci->valid)

	memset(uci, 0, sizeof(*uci));



	err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group);

	if (err)

		return err;



	if (!uci->valid)

		microcode_init_cpu(cpu);

	microcode_init_cpu(cpu, resume);



	return 0;

}



static int mc_sysdev_add(struct sys_device *sys_dev)

{

	return __mc_sysdev_add(sys_dev, 0);

}



static int mc_sysdev_remove(struct sys_device *sys_dev)

{

	int cpu = sys_dev->id;



	if (!cpu_online(cpu))

		return 0;



	pr_debug("Microcode:CPU %d removed\n", cpu);

	/* If suspend_cpu_hotplug is set, the system is suspending and we should

	 * keep the microcode in memory for the resume.

	 */

	if (!suspend_cpu_hotplug)

	microcode_fini_cpu(cpu);

	sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);

	return 0;
@@ -774,16 +766,34 @@ mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) 


	sys_dev = get_cpu_sysdev(cpu);

	switch (action) {

	case CPU_UP_CANCELED_FROZEN:

		/* The CPU refused to come up during a system resume */

		microcode_fini_cpu(cpu);

		break;

	case CPU_ONLINE:

	case CPU_ONLINE_FROZEN:

	case CPU_DOWN_FAILED:

	case CPU_DOWN_FAILED_FROZEN:

		mc_sysdev_add(sys_dev);

		break;

	case CPU_ONLINE_FROZEN:

		/* System-wide resume is in progress, try to apply microcode */

		if (apply_microcode_check_cpu(cpu)) {

			/* The application of microcode failed */

			microcode_fini_cpu(cpu);

			__mc_sysdev_add(sys_dev, 1);

			break;

		}

	case CPU_DOWN_FAILED_FROZEN:

		if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group))

			printk(KERN_ERR "Microcode: Failed to create the sysfs "

				"group for CPU%d\n", cpu);

		break;

	case CPU_DOWN_PREPARE:

	case CPU_DOWN_PREPARE_FROZEN:

		mc_sysdev_remove(sys_dev);

		break;

	case CPU_DOWN_PREPARE_FROZEN:

		/* Suspend is in progress, only remove the interface */

		sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);

		break;

	}

	return NOTIFY_OK;

}

kernel/cpu.c

+0 −10
Original line number Diff line number Diff line
@@ -262,12 +262,6 @@ int __cpuinit cpu_up(unsigned int cpu) 
}



#ifdef CONFIG_SUSPEND_SMP

/* Needed to prevent the microcode driver from requesting firmware in its CPU

 * hotplug notifier during the suspend/resume.

 */

int suspend_cpu_hotplug;

EXPORT_SYMBOL(suspend_cpu_hotplug);



static cpumask_t frozen_cpus;



int disable_nonboot_cpus(void)
@@ -275,7 +269,6 @@ int disable_nonboot_cpus(void) 
	int cpu, first_cpu, error = 0;



	mutex_lock(&cpu_add_remove_lock);

	suspend_cpu_hotplug = 1;

	first_cpu = first_cpu(cpu_online_map);

	/* We take down all of the non-boot CPUs in one shot to avoid races

	 * with the userspace trying to use the CPU hotplug at the same time
@@ -302,7 +295,6 @@ int disable_nonboot_cpus(void) 
	} else {

		printk(KERN_ERR "Non-boot CPUs are not disabled\n");

	}

	suspend_cpu_hotplug = 0;

	mutex_unlock(&cpu_add_remove_lock);

	return error;

}
@@ -317,7 +309,6 @@ void enable_nonboot_cpus(void) 
	if (cpus_empty(frozen_cpus))

		goto out;



	suspend_cpu_hotplug = 1;

	printk("Enabling non-boot CPUs ...\n");

	for_each_cpu_mask(cpu, frozen_cpus) {

		error = _cpu_up(cpu, 1);
@@ -328,7 +319,6 @@ void enable_nonboot_cpus(void) 
		printk(KERN_WARNING "Error taking CPU%d up: %d\n", cpu, error);

	}

	cpus_clear(frozen_cpus);

	suspend_cpu_hotplug = 0;

out:

	mutex_unlock(&cpu_add_remove_lock);

}