kernel-ark/arch/powerpc/kernel/sysfs.c
Rafael J. Wysocki 8bb7844286 Add suspend-related notifications for CPU hotplug
Since nonboot CPUs are now disabled after tasks and devices have been
frozen and the CPU hotplug infrastructure is used for this purpose, we need
special CPU hotplug notifications that will help the CPU-hotplug-aware
subsystems distinguish normal CPU hotplug events from CPU hotplug events
related to a system-wide suspend or resume operation in progress.  This
patch introduces such notifications and causes them to be used during
suspend and resume transitions.  It also changes all of the
CPU-hotplug-aware subsystems to take these notifications into consideration
(for now they are handled in the same way as the corresponding "normal"
ones).

[oleg@tv-sign.ru: cleanups]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-09 12:30:56 -07:00

505 lines
12 KiB
C

#include <linux/sysdev.h>
#include <linux/cpu.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/module.h>
#include <linux/nodemask.h>
#include <linux/cpumask.h>
#include <linux/notifier.h>
#include <asm/current.h>
#include <asm/processor.h>
#include <asm/cputable.h>
#include <asm/firmware.h>
#include <asm/hvcall.h>
#include <asm/prom.h>
#include <asm/paca.h>
#include <asm/lppaca.h>
#include <asm/machdep.h>
#include <asm/smp.h>
static DEFINE_PER_CPU(struct cpu, cpu_devices);
/* SMT stuff */
#ifdef CONFIG_PPC_MULTIPLATFORM
/* Time in microseconds we delay before sleeping in the idle loop */
DEFINE_PER_CPU(unsigned long, smt_snooze_delay) = { 100 };
static ssize_t store_smt_snooze_delay(struct sys_device *dev, const char *buf,
size_t count)
{
struct cpu *cpu = container_of(dev, struct cpu, sysdev);
ssize_t ret;
unsigned long snooze;
ret = sscanf(buf, "%lu", &snooze);
if (ret != 1)
return -EINVAL;
per_cpu(smt_snooze_delay, cpu->sysdev.id) = snooze;
return count;
}
static ssize_t show_smt_snooze_delay(struct sys_device *dev, char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, sysdev);
return sprintf(buf, "%lu\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
}
static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
store_smt_snooze_delay);
/* Only parse OF options if the matching cmdline option was not specified */
static int smt_snooze_cmdline;
static int __init smt_setup(void)
{
struct device_node *options;
const unsigned int *val;
unsigned int cpu;
if (!cpu_has_feature(CPU_FTR_SMT))
return -ENODEV;
options = of_find_node_by_path("/options");
if (!options)
return -ENODEV;
val = of_get_property(options, "ibm,smt-snooze-delay", NULL);
if (!smt_snooze_cmdline && val) {
for_each_possible_cpu(cpu)
per_cpu(smt_snooze_delay, cpu) = *val;
}
of_node_put(options);
return 0;
}
__initcall(smt_setup);
static int __init setup_smt_snooze_delay(char *str)
{
unsigned int cpu;
int snooze;
if (!cpu_has_feature(CPU_FTR_SMT))
return 1;
smt_snooze_cmdline = 1;
if (get_option(&str, &snooze)) {
for_each_possible_cpu(cpu)
per_cpu(smt_snooze_delay, cpu) = snooze;
}
return 1;
}
__setup("smt-snooze-delay=", setup_smt_snooze_delay);
#endif /* CONFIG_PPC_MULTIPLATFORM */
/*
* Enabling PMCs will slow partition context switch times so we only do
* it the first time we write to the PMCs.
*/
static DEFINE_PER_CPU(char, pmcs_enabled);
void ppc64_enable_pmcs(void)
{
/* Only need to enable them once */
if (__get_cpu_var(pmcs_enabled))
return;
__get_cpu_var(pmcs_enabled) = 1;
if (ppc_md.enable_pmcs)
ppc_md.enable_pmcs();
}
EXPORT_SYMBOL(ppc64_enable_pmcs);
/* XXX convert to rusty's on_one_cpu */
static unsigned long run_on_cpu(unsigned long cpu,
unsigned long (*func)(unsigned long),
unsigned long arg)
{
cpumask_t old_affinity = current->cpus_allowed;
unsigned long ret;
/* should return -EINVAL to userspace */
if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
return 0;
ret = func(arg);
set_cpus_allowed(current, old_affinity);
return ret;
}
#define SYSFS_PMCSETUP(NAME, ADDRESS) \
static unsigned long read_##NAME(unsigned long junk) \
{ \
return mfspr(ADDRESS); \
} \
static unsigned long write_##NAME(unsigned long val) \
{ \
ppc64_enable_pmcs(); \
mtspr(ADDRESS, val); \
return 0; \
} \
static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
{ \
struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
return sprintf(buf, "%lx\n", val); \
} \
static ssize_t __attribute_used__ \
store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
{ \
struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
unsigned long val; \
int ret = sscanf(buf, "%lx", &val); \
if (ret != 1) \
return -EINVAL; \
run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
return count; \
}
/* Let's define all possible registers, we'll only hook up the ones
* that are implemented on the current processor
*/
SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
SYSFS_PMCSETUP(purr, SPRN_PURR);
SYSFS_PMCSETUP(spurr, SPRN_SPURR);
SYSFS_PMCSETUP(dscr, SPRN_DSCR);
SYSFS_PMCSETUP(pa6t_pmc0, SPRN_PA6T_PMC0);
SYSFS_PMCSETUP(pa6t_pmc1, SPRN_PA6T_PMC1);
SYSFS_PMCSETUP(pa6t_pmc2, SPRN_PA6T_PMC2);
SYSFS_PMCSETUP(pa6t_pmc3, SPRN_PA6T_PMC3);
SYSFS_PMCSETUP(pa6t_pmc4, SPRN_PA6T_PMC4);
SYSFS_PMCSETUP(pa6t_pmc5, SPRN_PA6T_PMC5);
static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
static struct sysdev_attribute ibm_common_attrs[] = {
_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
};
static struct sysdev_attribute ibm_pmc_attrs[] = {
_SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
_SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
_SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
_SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
_SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
_SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
_SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
_SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
};
static struct sysdev_attribute pa6t_attrs[] = {
_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
_SYSDEV_ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
_SYSDEV_ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
_SYSDEV_ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
_SYSDEV_ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
_SYSDEV_ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
_SYSDEV_ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
};
static void register_cpu_online(unsigned int cpu)
{
struct cpu *c = &per_cpu(cpu_devices, cpu);
struct sys_device *s = &c->sysdev;
struct sysdev_attribute *attrs, *pmc_attrs;
int i, nattrs;
if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
cpu_has_feature(CPU_FTR_SMT))
sysdev_create_file(s, &attr_smt_snooze_delay);
/* PMC stuff */
switch (cur_cpu_spec->pmc_type) {
case PPC_PMC_IBM:
attrs = ibm_common_attrs;
nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = ibm_pmc_attrs;
break;
case PPC_PMC_PA6T:
/* PA Semi starts counting at PMC0 */
attrs = pa6t_attrs;
nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = NULL;
break;
default:
attrs = NULL;
nattrs = 0;
pmc_attrs = NULL;
}
for (i = 0; i < nattrs; i++)
sysdev_create_file(s, &attrs[i]);
if (pmc_attrs)
for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
sysdev_create_file(s, &pmc_attrs[i]);
if (cpu_has_feature(CPU_FTR_MMCRA))
sysdev_create_file(s, &attr_mmcra);
if (cpu_has_feature(CPU_FTR_PURR))
sysdev_create_file(s, &attr_purr);
if (cpu_has_feature(CPU_FTR_SPURR))
sysdev_create_file(s, &attr_spurr);
if (cpu_has_feature(CPU_FTR_DSCR))
sysdev_create_file(s, &attr_dscr);
}
#ifdef CONFIG_HOTPLUG_CPU
static void unregister_cpu_online(unsigned int cpu)
{
struct cpu *c = &per_cpu(cpu_devices, cpu);
struct sys_device *s = &c->sysdev;
struct sysdev_attribute *attrs, *pmc_attrs;
int i, nattrs;
BUG_ON(!c->hotpluggable);
if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
cpu_has_feature(CPU_FTR_SMT))
sysdev_remove_file(s, &attr_smt_snooze_delay);
/* PMC stuff */
switch (cur_cpu_spec->pmc_type) {
case PPC_PMC_IBM:
attrs = ibm_common_attrs;
nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = ibm_pmc_attrs;
break;
case PPC_PMC_PA6T:
/* PA Semi starts counting at PMC0 */
attrs = pa6t_attrs;
nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
pmc_attrs = NULL;
break;
default:
attrs = NULL;
nattrs = 0;
pmc_attrs = NULL;
}
for (i = 0; i < nattrs; i++)
sysdev_remove_file(s, &attrs[i]);
if (pmc_attrs)
for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
sysdev_remove_file(s, &pmc_attrs[i]);
if (cpu_has_feature(CPU_FTR_MMCRA))
sysdev_remove_file(s, &attr_mmcra);
if (cpu_has_feature(CPU_FTR_PURR))
sysdev_remove_file(s, &attr_purr);
if (cpu_has_feature(CPU_FTR_SPURR))
sysdev_remove_file(s, &attr_spurr);
if (cpu_has_feature(CPU_FTR_DSCR))
sysdev_remove_file(s, &attr_dscr);
}
#endif /* CONFIG_HOTPLUG_CPU */
static int __cpuinit 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 NOTIFY_OK;
}
static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
.notifier_call = sysfs_cpu_notify,
};
static DEFINE_MUTEX(cpu_mutex);
int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
{
int cpu;
mutex_lock(&cpu_mutex);
for_each_possible_cpu(cpu) {
sysdev_create_file(get_cpu_sysdev(cpu), attr);
}
mutex_unlock(&cpu_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
{
int cpu;
struct sys_device *sysdev;
mutex_lock(&cpu_mutex);
for_each_possible_cpu(cpu) {
sysdev = get_cpu_sysdev(cpu);
sysfs_create_group(&sysdev->kobj, attrs);
}
mutex_unlock(&cpu_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
{
int cpu;
mutex_lock(&cpu_mutex);
for_each_possible_cpu(cpu) {
sysdev_remove_file(get_cpu_sysdev(cpu), attr);
}
mutex_unlock(&cpu_mutex);
}
EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
{
int cpu;
struct sys_device *sysdev;
mutex_lock(&cpu_mutex);
for_each_possible_cpu(cpu) {
sysdev = get_cpu_sysdev(cpu);
sysfs_remove_group(&sysdev->kobj, attrs);
}
mutex_unlock(&cpu_mutex);
}
EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
/* NUMA stuff */
#ifdef CONFIG_NUMA
static void register_nodes(void)
{
int i;
for (i = 0; i < MAX_NUMNODES; i++)
register_one_node(i);
}
int sysfs_add_device_to_node(struct sys_device *dev, int nid)
{
struct node *node = &node_devices[nid];
return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
kobject_name(&dev->kobj));
}
void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
{
struct node *node = &node_devices[nid];
sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
}
#else
static void register_nodes(void)
{
return;
}
#endif
EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
/* Only valid if CPU is present. */
static ssize_t show_physical_id(struct sys_device *dev, char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, sysdev);
return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
}
static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
static int __init topology_init(void)
{
int cpu;
register_nodes();
register_cpu_notifier(&sysfs_cpu_nb);
for_each_possible_cpu(cpu) {
struct cpu *c = &per_cpu(cpu_devices, cpu);
/*
* For now, we just see if the system supports making
* the RTAS calls for CPU hotplug. But, there may be a
* more comprehensive way to do this for an individual
* CPU. For instance, the boot cpu might never be valid
* for hotplugging.
*/
if (ppc_md.cpu_die)
c->hotpluggable = 1;
if (cpu_online(cpu) || c->hotpluggable) {
register_cpu(c, cpu);
sysdev_create_file(&c->sysdev, &attr_physical_id);
}
if (cpu_online(cpu))
register_cpu_online(cpu);
}
return 0;
}
subsys_initcall(topology_init);