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Message-Id: <200704212318.34838.rjw@sisk.pl>
Date: Sat, 21 Apr 2007 23:18:34 +0200
From: "Rafael J. Wysocki" <rjw@...k.pl>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: Gautham R Shenoy <ego@...ibm.com>, Pavel Machek <pavel@....cz>,
LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH -mm 2/2] microcode: use suspend-related CPU hotplug notifications
From: Rafael J. Wysocki <rjw@...k.pl>
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: Rafael J. Wysocki <rjw@...k.pl>
---
arch/i386/kernel/microcode.c | 62 ++++++++++++++++++++++++-------------------
kernel/cpu.c | 10 ------
2 files changed, 36 insertions(+), 36 deletions(-)
Index: linux-2.6.21-rc6-mm1/arch/i386/kernel/microcode.c
===================================================================
--- linux-2.6.21-rc6-mm1.orig/arch/i386/kernel/microcode.c 2007-04-21 10:16:36.000000000 +0200
+++ linux-2.6.21-rc6-mm1/arch/i386/kernel/microcode.c 2007-04-21 11:03:30.000000000 +0200
@@ -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 cp
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 cp
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(µcode_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(µcode_mutex);
set_cpus_allowed(current, old);
@@ -702,7 +702,7 @@ static struct attribute_group mc_attr_gr
.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;
@@ -711,39 +711,31 @@ static int mc_sysdev_add(struct sys_devi
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));
+ 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);
+ 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 *n
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;
}
Index: linux-2.6.21-rc6-mm1/kernel/cpu.c
===================================================================
--- linux-2.6.21-rc6-mm1.orig/kernel/cpu.c 2007-04-21 10:16:36.000000000 +0200
+++ linux-2.6.21-rc6-mm1/kernel/cpu.c 2007-04-21 10:16:50.000000000 +0200
@@ -266,12 +266,6 @@ 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)
@@ -279,7 +273,6 @@ 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
@@ -306,7 +299,6 @@ 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;
}
@@ -321,7 +313,6 @@ 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);
@@ -332,7 +323,6 @@ 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);
}
-
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