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Diffstat (limited to 'arch/s390/kernel/smp.c')
-rw-r--r--arch/s390/kernel/smp.c575
1 files changed, 422 insertions, 153 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 264ea906db4..aa37fa15451 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -42,6 +42,7 @@
#include <asm/tlbflush.h>
#include <asm/timer.h>
#include <asm/lowcore.h>
+#include <asm/sclp.h>
#include <asm/cpu.h>
/*
@@ -53,11 +54,27 @@ EXPORT_SYMBOL(lowcore_ptr);
cpumask_t cpu_online_map = CPU_MASK_NONE;
EXPORT_SYMBOL(cpu_online_map);
-cpumask_t cpu_possible_map = CPU_MASK_NONE;
+cpumask_t cpu_possible_map = CPU_MASK_ALL;
EXPORT_SYMBOL(cpu_possible_map);
static struct task_struct *current_set[NR_CPUS];
+static u8 smp_cpu_type;
+static int smp_use_sigp_detection;
+
+enum s390_cpu_state {
+ CPU_STATE_STANDBY,
+ CPU_STATE_CONFIGURED,
+};
+
+#ifdef CONFIG_HOTPLUG_CPU
+static DEFINE_MUTEX(smp_cpu_state_mutex);
+#endif
+static int smp_cpu_state[NR_CPUS];
+
+static DEFINE_PER_CPU(struct cpu, cpu_devices);
+DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
+
static void smp_ext_bitcall(int, ec_bit_sig);
/*
@@ -193,6 +210,33 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
}
EXPORT_SYMBOL(smp_call_function_single);
+/**
+ * smp_call_function_mask(): Run a function on a set of other CPUs.
+ * @mask: The set of cpus to run on. Must not include the current cpu.
+ * @func: The function to run. This must be fast and non-blocking.
+ * @info: An arbitrary pointer to pass to the function.
+ * @wait: If true, wait (atomically) until function has completed on other CPUs.
+ *
+ * Returns 0 on success, else a negative status code.
+ *
+ * If @wait is true, then returns once @func has returned; otherwise
+ * it returns just before the target cpu calls @func.
+ *
+ * You must not call this function with disabled interrupts or from a
+ * hardware interrupt handler or from a bottom half handler.
+ */
+int
+smp_call_function_mask(cpumask_t mask,
+ void (*func)(void *), void *info,
+ int wait)
+{
+ preempt_disable();
+ __smp_call_function_map(func, info, 0, wait, mask);
+ preempt_enable();
+ return 0;
+}
+EXPORT_SYMBOL(smp_call_function_mask);
+
void smp_send_stop(void)
{
int cpu, rc;
@@ -217,33 +261,6 @@ void smp_send_stop(void)
}
/*
- * Reboot, halt and power_off routines for SMP.
- */
-void machine_restart_smp(char *__unused)
-{
- smp_send_stop();
- do_reipl();
-}
-
-void machine_halt_smp(void)
-{
- smp_send_stop();
- if (MACHINE_IS_VM && strlen(vmhalt_cmd) > 0)
- __cpcmd(vmhalt_cmd, NULL, 0, NULL);
- signal_processor(smp_processor_id(), sigp_stop_and_store_status);
- for (;;);
-}
-
-void machine_power_off_smp(void)
-{
- smp_send_stop();
- if (MACHINE_IS_VM && strlen(vmpoff_cmd) > 0)
- __cpcmd(vmpoff_cmd, NULL, 0, NULL);
- signal_processor(smp_processor_id(), sigp_stop_and_store_status);
- for (;;);
-}
-
-/*
* This is the main routine where commands issued by other
* cpus are handled.
*/
@@ -355,6 +372,13 @@ void smp_ctl_clear_bit(int cr, int bit)
}
EXPORT_SYMBOL(smp_ctl_clear_bit);
+/*
+ * In early ipl state a temp. logically cpu number is needed, so the sigp
+ * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on
+ * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1.
+ */
+#define CPU_INIT_NO 1
+
#if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
/*
@@ -375,9 +399,10 @@ static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu)
"kernel was compiled with NR_CPUS=%i\n", cpu, NR_CPUS);
return;
}
- zfcpdump_save_areas[cpu] = alloc_bootmem(sizeof(union save_area));
- __cpu_logical_map[1] = (__u16) phy_cpu;
- while (signal_processor(1, sigp_stop_and_store_status) == sigp_busy)
+ zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL);
+ __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu;
+ while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) ==
+ sigp_busy)
cpu_relax();
memcpy(zfcpdump_save_areas[cpu],
(void *)(unsigned long) store_prefix() + SAVE_AREA_BASE,
@@ -397,32 +422,155 @@ static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { }
#endif /* CONFIG_ZFCPDUMP || CONFIG_ZFCPDUMP_MODULE */
-/*
- * Lets check how many CPUs we have.
- */
-static unsigned int __init smp_count_cpus(void)
+static int cpu_stopped(int cpu)
{
- unsigned int cpu, num_cpus;
- __u16 boot_cpu_addr;
+ __u32 status;
- /*
- * cpu 0 is the boot cpu. See smp_prepare_boot_cpu.
- */
+ /* Check for stopped state */
+ if (signal_processor_ps(&status, 0, cpu, sigp_sense) ==
+ sigp_status_stored) {
+ if (status & 0x40)
+ return 1;
+ }
+ return 0;
+}
+
+static int cpu_known(int cpu_id)
+{
+ int cpu;
+
+ for_each_present_cpu(cpu) {
+ if (__cpu_logical_map[cpu] == cpu_id)
+ return 1;
+ }
+ return 0;
+}
+
+static int smp_rescan_cpus_sigp(cpumask_t avail)
+{
+ int cpu_id, logical_cpu;
+
+ logical_cpu = first_cpu(avail);
+ if (logical_cpu == NR_CPUS)
+ return 0;
+ for (cpu_id = 0; cpu_id <= 65535; cpu_id++) {
+ if (cpu_known(cpu_id))
+ continue;
+ __cpu_logical_map[logical_cpu] = cpu_id;
+ if (!cpu_stopped(logical_cpu))
+ continue;
+ cpu_set(logical_cpu, cpu_present_map);
+ smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
+ logical_cpu = next_cpu(logical_cpu, avail);
+ if (logical_cpu == NR_CPUS)
+ break;
+ }
+ return 0;
+}
+
+static int smp_rescan_cpus_sclp(cpumask_t avail)
+{
+ struct sclp_cpu_info *info;
+ int cpu_id, logical_cpu, cpu;
+ int rc;
+
+ logical_cpu = first_cpu(avail);
+ if (logical_cpu == NR_CPUS)
+ return 0;
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+ rc = sclp_get_cpu_info(info);
+ if (rc)
+ goto out;
+ for (cpu = 0; cpu < info->combined; cpu++) {
+ if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
+ continue;
+ cpu_id = info->cpu[cpu].address;
+ if (cpu_known(cpu_id))
+ continue;
+ __cpu_logical_map[logical_cpu] = cpu_id;
+ cpu_set(logical_cpu, cpu_present_map);
+ if (cpu >= info->configured)
+ smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY;
+ else
+ smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
+ logical_cpu = next_cpu(logical_cpu, avail);
+ if (logical_cpu == NR_CPUS)
+ break;
+ }
+out:
+ kfree(info);
+ return rc;
+}
+
+static int smp_rescan_cpus(void)
+{
+ cpumask_t avail;
+
+ cpus_xor(avail, cpu_possible_map, cpu_present_map);
+ if (smp_use_sigp_detection)
+ return smp_rescan_cpus_sigp(avail);
+ else
+ return smp_rescan_cpus_sclp(avail);
+}
+
+static void __init smp_detect_cpus(void)
+{
+ unsigned int cpu, c_cpus, s_cpus;
+ struct sclp_cpu_info *info;
+ u16 boot_cpu_addr, cpu_addr;
+
+ c_cpus = 1;
+ s_cpus = 0;
boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
- current_thread_info()->cpu = 0;
- num_cpus = 1;
- for (cpu = 0; cpu <= 65535; cpu++) {
- if ((__u16) cpu == boot_cpu_addr)
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ panic("smp_detect_cpus failed to allocate memory\n");
+ /* Use sigp detection algorithm if sclp doesn't work. */
+ if (sclp_get_cpu_info(info)) {
+ smp_use_sigp_detection = 1;
+ for (cpu = 0; cpu <= 65535; cpu++) {
+ if (cpu == boot_cpu_addr)
+ continue;
+ __cpu_logical_map[CPU_INIT_NO] = cpu;
+ if (!cpu_stopped(CPU_INIT_NO))
+ continue;
+ smp_get_save_area(c_cpus, cpu);
+ c_cpus++;
+ }
+ goto out;
+ }
+
+ if (info->has_cpu_type) {
+ for (cpu = 0; cpu < info->combined; cpu++) {
+ if (info->cpu[cpu].address == boot_cpu_addr) {
+ smp_cpu_type = info->cpu[cpu].type;
+ break;
+ }
+ }
+ }
+
+ for (cpu = 0; cpu < info->combined; cpu++) {
+ if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
+ continue;
+ cpu_addr = info->cpu[cpu].address;
+ if (cpu_addr == boot_cpu_addr)
continue;
- __cpu_logical_map[1] = (__u16) cpu;
- if (signal_processor(1, sigp_sense) == sigp_not_operational)
+ __cpu_logical_map[CPU_INIT_NO] = cpu_addr;
+ if (!cpu_stopped(CPU_INIT_NO)) {
+ s_cpus++;
continue;
- smp_get_save_area(num_cpus, cpu);
- num_cpus++;
+ }
+ smp_get_save_area(c_cpus, cpu_addr);
+ c_cpus++;
}
- printk("Detected %d CPU's\n", (int) num_cpus);
- printk("Boot cpu address %2X\n", boot_cpu_addr);
- return num_cpus;
+out:
+ kfree(info);
+ printk(KERN_INFO "CPUs: %d configured, %d standby\n", c_cpus, s_cpus);
+ get_online_cpus();
+ smp_rescan_cpus();
+ put_online_cpus();
}
/*
@@ -453,8 +601,6 @@ int __cpuinit start_secondary(void *cpuvoid)
return 0;
}
-DEFINE_PER_CPU(struct s390_idle_data, s390_idle);
-
static void __init smp_create_idle(unsigned int cpu)
{
struct task_struct *p;
@@ -470,37 +616,82 @@ static void __init smp_create_idle(unsigned int cpu)
spin_lock_init(&(&per_cpu(s390_idle, cpu))->lock);
}
-static int cpu_stopped(int cpu)
+static int __cpuinit smp_alloc_lowcore(int cpu)
{
- __u32 status;
+ unsigned long async_stack, panic_stack;
+ struct _lowcore *lowcore;
+ int lc_order;
+
+ lc_order = sizeof(long) == 8 ? 1 : 0;
+ lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
+ if (!lowcore)
+ return -ENOMEM;
+ async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
+ if (!async_stack)
+ goto out_async_stack;
+ panic_stack = __get_free_page(GFP_KERNEL);
+ if (!panic_stack)
+ goto out_panic_stack;
+
+ *lowcore = S390_lowcore;
+ lowcore->async_stack = async_stack + ASYNC_SIZE;
+ lowcore->panic_stack = panic_stack + PAGE_SIZE;
- /* Check for stopped state */
- if (signal_processor_ps(&status, 0, cpu, sigp_sense) ==
- sigp_status_stored) {
- if (status & 0x40)
- return 1;
+#ifndef CONFIG_64BIT
+ if (MACHINE_HAS_IEEE) {
+ unsigned long save_area;
+
+ save_area = get_zeroed_page(GFP_KERNEL);
+ if (!save_area)
+ goto out_save_area;
+ lowcore->extended_save_area_addr = (u32) save_area;
}
+#endif
+ lowcore_ptr[cpu] = lowcore;
return 0;
+
+#ifndef CONFIG_64BIT
+out_save_area:
+ free_page(panic_stack);
+#endif
+out_panic_stack:
+ free_pages(async_stack, ASYNC_ORDER);
+out_async_stack:
+ free_pages((unsigned long) lowcore, lc_order);
+ return -ENOMEM;
}
-/* Upping and downing of CPUs */
+#ifdef CONFIG_HOTPLUG_CPU
+static void smp_free_lowcore(int cpu)
+{
+ struct _lowcore *lowcore;
+ int lc_order;
+
+ lc_order = sizeof(long) == 8 ? 1 : 0;
+ lowcore = lowcore_ptr[cpu];
+#ifndef CONFIG_64BIT
+ if (MACHINE_HAS_IEEE)
+ free_page((unsigned long) lowcore->extended_save_area_addr);
+#endif
+ free_page(lowcore->panic_stack - PAGE_SIZE);
+ free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER);
+ free_pages((unsigned long) lowcore, lc_order);
+ lowcore_ptr[cpu] = NULL;
+}
+#endif /* CONFIG_HOTPLUG_CPU */
-int __cpu_up(unsigned int cpu)
+/* Upping and downing of CPUs */
+int __cpuinit __cpu_up(unsigned int cpu)
{
struct task_struct *idle;
struct _lowcore *cpu_lowcore;
struct stack_frame *sf;
sigp_ccode ccode;
- int curr_cpu;
- for (curr_cpu = 0; curr_cpu <= 65535; curr_cpu++) {
- __cpu_logical_map[cpu] = (__u16) curr_cpu;
- if (cpu_stopped(cpu))
- break;
- }
-
- if (!cpu_stopped(cpu))
- return -ENODEV;
+ if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
+ return -EIO;
+ if (smp_alloc_lowcore(cpu))
+ return -ENOMEM;
ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
cpu, sigp_set_prefix);
@@ -515,6 +706,7 @@ int __cpu_up(unsigned int cpu)
cpu_lowcore = lowcore_ptr[cpu];
cpu_lowcore->kernel_stack = (unsigned long)
task_stack_page(idle) + THREAD_SIZE;
+ cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle);
sf = (struct stack_frame *) (cpu_lowcore->kernel_stack
- sizeof(struct pt_regs)
- sizeof(struct stack_frame));
@@ -528,6 +720,8 @@ int __cpu_up(unsigned int cpu)
cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
cpu_lowcore->current_task = (unsigned long) idle;
cpu_lowcore->cpu_data.cpu_nr = cpu;
+ cpu_lowcore->softirq_pending = 0;
+ cpu_lowcore->ext_call_fast = 0;
eieio();
while (signal_processor(cpu, sigp_restart) == sigp_busy)
@@ -538,44 +732,20 @@ int __cpu_up(unsigned int cpu)
return 0;
}
-static unsigned int __initdata additional_cpus;
-static unsigned int __initdata possible_cpus;
-
-void __init smp_setup_cpu_possible_map(void)
+static int __init setup_possible_cpus(char *s)
{
- unsigned int phy_cpus, pos_cpus, cpu;
-
- phy_cpus = smp_count_cpus();
- pos_cpus = min(phy_cpus + additional_cpus, (unsigned int) NR_CPUS);
-
- if (possible_cpus)
- pos_cpus = min(possible_cpus, (unsigned int) NR_CPUS);
+ int pcpus, cpu;
- for (cpu = 0; cpu < pos_cpus; cpu++)
+ pcpus = simple_strtoul(s, NULL, 0);
+ cpu_possible_map = cpumask_of_cpu(0);
+ for (cpu = 1; cpu < pcpus && cpu < NR_CPUS; cpu++)
cpu_set(cpu, cpu_possible_map);
-
- phy_cpus = min(phy_cpus, pos_cpus);
-
- for (cpu = 0; cpu < phy_cpus; cpu++)
- cpu_set(cpu, cpu_present_map);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-static int __init setup_additional_cpus(char *s)
-{
- additional_cpus = simple_strtoul(s, NULL, 0);
- return 0;
-}
-early_param("additional_cpus", setup_additional_cpus);
-
-static int __init setup_possible_cpus(char *s)
-{
- possible_cpus = simple_strtoul(s, NULL, 0);
return 0;
}
early_param("possible_cpus", setup_possible_cpus);
+#ifdef CONFIG_HOTPLUG_CPU
+
int __cpu_disable(void)
{
struct ec_creg_mask_parms cr_parms;
@@ -612,7 +782,8 @@ void __cpu_die(unsigned int cpu)
/* Wait until target cpu is down */
while (!smp_cpu_not_running(cpu))
cpu_relax();
- printk("Processor %d spun down\n", cpu);
+ smp_free_lowcore(cpu);
+ printk(KERN_INFO "Processor %d spun down\n", cpu);
}
void cpu_die(void)
@@ -625,49 +796,19 @@ void cpu_die(void)
#endif /* CONFIG_HOTPLUG_CPU */
-/*
- * Cycle through the processors and setup structures.
- */
-
void __init smp_prepare_cpus(unsigned int max_cpus)
{
- unsigned long stack;
unsigned int cpu;
- int i;
+
+ smp_detect_cpus();
/* request the 0x1201 emergency signal external interrupt */
if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
panic("Couldn't request external interrupt 0x1201");
memset(lowcore_ptr, 0, sizeof(lowcore_ptr));
- /*
- * Initialize prefix pages and stacks for all possible cpus
- */
print_cpu_info(&S390_lowcore.cpu_data);
+ smp_alloc_lowcore(smp_processor_id());
- for_each_possible_cpu(i) {
- lowcore_ptr[i] = (struct _lowcore *)
- __get_free_pages(GFP_KERNEL | GFP_DMA,
- sizeof(void*) == 8 ? 1 : 0);
- stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
- if (!lowcore_ptr[i] || !stack)
- panic("smp_boot_cpus failed to allocate memory\n");
-
- *(lowcore_ptr[i]) = S390_lowcore;
- lowcore_ptr[i]->async_stack = stack + ASYNC_SIZE;
- stack = __get_free_pages(GFP_KERNEL, 0);
- if (!stack)
- panic("smp_boot_cpus failed to allocate memory\n");
- lowcore_ptr[i]->panic_stack = stack + PAGE_SIZE;
-#ifndef CONFIG_64BIT
- if (MACHINE_HAS_IEEE) {
- lowcore_ptr[i]->extended_save_area_addr =
- (__u32) __get_free_pages(GFP_KERNEL, 0);
- if (!lowcore_ptr[i]->extended_save_area_addr)
- panic("smp_boot_cpus failed to "
- "allocate memory\n");
- }
-#endif
- }
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE)
ctl_set_bit(14, 29); /* enable extended save area */
@@ -683,15 +824,17 @@ void __init smp_prepare_boot_cpu(void)
{
BUG_ON(smp_processor_id() != 0);
+ current_thread_info()->cpu = 0;
+ cpu_set(0, cpu_present_map);
cpu_set(0, cpu_online_map);
S390_lowcore.percpu_offset = __per_cpu_offset[0];
current_set[0] = current;
+ smp_cpu_state[0] = CPU_STATE_CONFIGURED;
spin_lock_init(&(&__get_cpu_var(s390_idle))->lock);
}
void __init smp_cpus_done(unsigned int max_cpus)
{
- cpu_present_map = cpu_possible_map;
}
/*
@@ -705,7 +848,79 @@ int setup_profiling_timer(unsigned int multiplier)
return 0;
}
-static DEFINE_PER_CPU(struct cpu, cpu_devices);
+#ifdef CONFIG_HOTPLUG_CPU
+static ssize_t cpu_configure_show(struct sys_device *dev, char *buf)
+{
+ ssize_t count;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]);
+ mutex_unlock(&smp_cpu_state_mutex);
+ return count;
+}
+
+static ssize_t cpu_configure_store(struct sys_device *dev, const char *buf,
+ size_t count)
+{
+ int cpu = dev->id;
+ int val, rc;
+ char delim;
+
+ if (sscanf(buf, "%d %c", &val, &delim) != 1)
+ return -EINVAL;
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ get_online_cpus();
+ rc = -EBUSY;
+ if (cpu_online(cpu))
+ goto out;
+ rc = 0;
+ switch (val) {
+ case 0:
+ if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) {
+ rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]);
+ if (!rc)
+ smp_cpu_state[cpu] = CPU_STATE_STANDBY;
+ }
+ break;
+ case 1:
+ if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) {
+ rc = sclp_cpu_configure(__cpu_logical_map[cpu]);
+ if (!rc)
+ smp_cpu_state[cpu] = CPU_STATE_CONFIGURED;
+ }
+ break;
+ default:
+ break;
+ }
+out:
+ put_online_cpus();
+ mutex_unlock(&smp_cpu_state_mutex);
+ return rc ? rc : count;
+}
+static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store);
+#endif /* CONFIG_HOTPLUG_CPU */
+
+static ssize_t show_cpu_address(struct sys_device *dev, char *buf)
+{
+ return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]);
+}
+static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL);
+
+
+static struct attribute *cpu_common_attrs[] = {
+#ifdef CONFIG_HOTPLUG_CPU
+ &attr_configure.attr,
+#endif
+ &attr_address.attr,
+ NULL,
+};
+
+static struct attribute_group cpu_common_attr_group = {
+ .attrs = cpu_common_attrs,
+};
static ssize_t show_capability(struct sys_device *dev, char *buf)
{
@@ -750,15 +965,15 @@ static ssize_t show_idle_time(struct sys_device *dev, char *buf)
}
static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL);
-static struct attribute *cpu_attrs[] = {
+static struct attribute *cpu_online_attrs[] = {
&attr_capability.attr,
&attr_idle_count.attr,
&attr_idle_time_us.attr,
NULL,
};
-static struct attribute_group cpu_attr_group = {
- .attrs = cpu_attrs,
+static struct attribute_group cpu_online_attr_group = {
+ .attrs = cpu_online_attrs,
};
static int __cpuinit smp_cpu_notify(struct notifier_block *self,
@@ -778,12 +993,12 @@ static int __cpuinit smp_cpu_notify(struct notifier_block *self,
idle->idle_time = 0;
idle->idle_count = 0;
spin_unlock_irq(&idle->lock);
- if (sysfs_create_group(&s->kobj, &cpu_attr_group))
+ if (sysfs_create_group(&s->kobj, &cpu_online_attr_group))
return NOTIFY_BAD;
break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
- sysfs_remove_group(&s->kobj, &cpu_attr_group);
+ sysfs_remove_group(&s->kobj, &cpu_online_attr_group);
break;
}
return NOTIFY_OK;
@@ -793,6 +1008,62 @@ static struct notifier_block __cpuinitdata smp_cpu_nb = {
.notifier_call = smp_cpu_notify,
};
+static int smp_add_present_cpu(int cpu)
+{
+ struct cpu *c = &per_cpu(cpu_devices, cpu);
+ struct sys_device *s = &c->sysdev;
+ int rc;
+
+ c->hotpluggable = 1;
+ rc = register_cpu(c, cpu);
+ if (rc)
+ goto out;
+ rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group);
+ if (rc)
+ goto out_cpu;
+ if (!cpu_online(cpu))
+ goto out;
+ rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group);
+ if (!rc)
+ return 0;
+ sysfs_remove_group(&s->kobj, &cpu_common_attr_group);
+out_cpu:
+#ifdef CONFIG_HOTPLUG_CPU
+ unregister_cpu(c);
+#endif
+out:
+ return rc;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static ssize_t rescan_store(struct sys_device *dev, const char *buf,
+ size_t count)
+{
+ cpumask_t newcpus;
+ int cpu;
+ int rc;
+
+ mutex_lock(&smp_cpu_state_mutex);
+ get_online_cpus();
+ newcpus = cpu_present_map;
+ rc = smp_rescan_cpus();
+ if (rc)
+ goto out;
+ cpus_andnot(newcpus, cpu_present_map, newcpus);
+ for_each_cpu_mask(cpu, newcpus) {
+ rc = smp_add_present_cpu(cpu);
+ if (rc)
+ cpu_clear(cpu, cpu_present_map);
+ }
+ rc = 0;
+out:
+ put_online_cpus();
+ mutex_unlock(&smp_cpu_state_mutex);
+ return rc ? rc : count;
+}
+static SYSDEV_ATTR(rescan, 0200, NULL, rescan_store);
+#endif /* CONFIG_HOTPLUG_CPU */
+
static int __init topology_init(void)
{
int cpu;
@@ -800,16 +1071,14 @@ static int __init topology_init(void)
register_cpu_notifier(&smp_cpu_nb);
- for_each_possible_cpu(cpu) {
- struct cpu *c = &per_cpu(cpu_devices, cpu);
- struct sys_device *s = &c->sysdev;
-
- c->hotpluggable = 1;
- register_cpu(c, cpu);
- if (!cpu_online(cpu))
- continue;
- s = &c->sysdev;
- rc = sysfs_create_group(&s->kobj, &cpu_attr_group);
+#ifdef CONFIG_HOTPLUG_CPU
+ rc = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
+ &attr_rescan.attr);
+ if (rc)
+ return rc;
+#endif
+ for_each_present_cpu(cpu) {
+ rc = smp_add_present_cpu(cpu);
if (rc)
return rc;
}