blob: 8127ebd59c4d81f4e8368e7728ad49bf3a173900 [file] [log] [blame]
/*
* arch/s390/kernel/smp.c
*
* Copyright IBM Corp. 1999, 2009
* Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
* Heiko Carstens (heiko.carstens@de.ibm.com)
*
* based on other smp stuff by
* (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net>
* (c) 1998 Ingo Molnar
*
* We work with logical cpu numbering everywhere we can. The only
* functions using the real cpu address (got from STAP) are the sigp
* functions. For all other functions we use the identity mapping.
* That means that cpu_number_map[i] == i for every cpu. cpu_number_map is
* used e.g. to find the idle task belonging to a logical cpu. Every array
* in the kernel is sorted by the logical cpu number and not by the physical
* one which is causing all the confusion with __cpu_logical_map and
* cpu_number_map in other architectures.
*/
#define KMSG_COMPONENT "cpu"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/err.h>
#include <linux/spinlock.h>
#include <linux/kernel_stat.h>
#include <linux/delay.h>
#include <linux/cache.h>
#include <linux/interrupt.h>
#include <linux/irqflags.h>
#include <linux/cpu.h>
#include <linux/timex.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <asm/asm-offsets.h>
#include <asm/ipl.h>
#include <asm/setup.h>
#include <asm/sigp.h>
#include <asm/pgalloc.h>
#include <asm/irq.h>
#include <asm/s390_ext.h>
#include <asm/cpcmd.h>
#include <asm/tlbflush.h>
#include <asm/timer.h>
#include <asm/lowcore.h>
#include <asm/sclp.h>
#include <asm/cputime.h>
#include <asm/vdso.h>
#include <asm/cpu.h>
#include "entry.h"
/* logical cpu to cpu address */
unsigned short __cpu_logical_map[NR_CPUS];
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,
};
DEFINE_MUTEX(smp_cpu_state_mutex);
int smp_cpu_polarization[NR_CPUS];
static int smp_cpu_state[NR_CPUS];
static int cpu_management;
static DEFINE_PER_CPU(struct cpu, cpu_devices);
static void smp_ext_bitcall(int, int);
static int raw_cpu_stopped(int cpu)
{
u32 status;
switch (raw_sigp_ps(&status, 0, cpu, sigp_sense)) {
case sigp_status_stored:
/* Check for stopped and check stop state */
if (status & 0x50)
return 1;
break;
default:
break;
}
return 0;
}
static inline int cpu_stopped(int cpu)
{
return raw_cpu_stopped(cpu_logical_map(cpu));
}
void smp_switch_to_ipl_cpu(void (*func)(void *), void *data)
{
struct _lowcore *lc, *current_lc;
struct stack_frame *sf;
struct pt_regs *regs;
unsigned long sp;
if (smp_processor_id() == 0)
func(data);
__load_psw_mask(PSW_BASE_BITS | PSW_DEFAULT_KEY);
/* Disable lowcore protection */
__ctl_clear_bit(0, 28);
current_lc = lowcore_ptr[smp_processor_id()];
lc = lowcore_ptr[0];
if (!lc)
lc = current_lc;
lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
lc->restart_psw.addr = PSW_ADDR_AMODE | (unsigned long) smp_restart_cpu;
if (!cpu_online(0))
smp_switch_to_cpu(func, data, 0, stap(), __cpu_logical_map[0]);
while (sigp(0, sigp_stop_and_store_status) == sigp_busy)
cpu_relax();
sp = lc->panic_stack;
sp -= sizeof(struct pt_regs);
regs = (struct pt_regs *) sp;
memcpy(&regs->gprs, &current_lc->gpregs_save_area, sizeof(regs->gprs));
regs->psw = lc->psw_save_area;
sp -= STACK_FRAME_OVERHEAD;
sf = (struct stack_frame *) sp;
sf->back_chain = regs->gprs[15];
smp_switch_to_cpu(func, data, sp, stap(), __cpu_logical_map[0]);
}
void smp_send_stop(void)
{
int cpu, rc;
/* Disable all interrupts/machine checks */
__load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
trace_hardirqs_off();
/* stop all processors */
for_each_online_cpu(cpu) {
if (cpu == smp_processor_id())
continue;
do {
rc = sigp(cpu, sigp_stop);
} while (rc == sigp_busy);
while (!cpu_stopped(cpu))
cpu_relax();
}
}
/*
* This is the main routine where commands issued by other
* cpus are handled.
*/
static void do_ext_call_interrupt(__u16 code)
{
unsigned long bits;
/*
* handle bit signal external calls
*
* For the ec_schedule signal we have to do nothing. All the work
* is done automatically when we return from the interrupt.
*/
bits = xchg(&S390_lowcore.ext_call_fast, 0);
if (test_bit(ec_call_function, &bits))
generic_smp_call_function_interrupt();
if (test_bit(ec_call_function_single, &bits))
generic_smp_call_function_single_interrupt();
}
/*
* Send an external call sigp to another cpu and return without waiting
* for its completion.
*/
static void smp_ext_bitcall(int cpu, int sig)
{
/*
* Set signaling bit in lowcore of target cpu and kick it
*/
set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast);
while (sigp(cpu, sigp_emergency_signal) == sigp_busy)
udelay(10);
}
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
{
int cpu;
for_each_cpu(cpu, mask)
smp_ext_bitcall(cpu, ec_call_function);
}
void arch_send_call_function_single_ipi(int cpu)
{
smp_ext_bitcall(cpu, ec_call_function_single);
}
#ifndef CONFIG_64BIT
/*
* this function sends a 'purge tlb' signal to another CPU.
*/
static void smp_ptlb_callback(void *info)
{
__tlb_flush_local();
}
void smp_ptlb_all(void)
{
on_each_cpu(smp_ptlb_callback, NULL, 1);
}
EXPORT_SYMBOL(smp_ptlb_all);
#endif /* ! CONFIG_64BIT */
/*
* this function sends a 'reschedule' IPI to another CPU.
* it goes straight through and wastes no time serializing
* anything. Worst case is that we lose a reschedule ...
*/
void smp_send_reschedule(int cpu)
{
smp_ext_bitcall(cpu, ec_schedule);
}
/*
* parameter area for the set/clear control bit callbacks
*/
struct ec_creg_mask_parms {
unsigned long orvals[16];
unsigned long andvals[16];
};
/*
* callback for setting/clearing control bits
*/
static void smp_ctl_bit_callback(void *info)
{
struct ec_creg_mask_parms *pp = info;
unsigned long cregs[16];
int i;
__ctl_store(cregs, 0, 15);
for (i = 0; i <= 15; i++)
cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i];
__ctl_load(cregs, 0, 15);
}
/*
* Set a bit in a control register of all cpus
*/
void smp_ctl_set_bit(int cr, int bit)
{
struct ec_creg_mask_parms parms;
memset(&parms.orvals, 0, sizeof(parms.orvals));
memset(&parms.andvals, 0xff, sizeof(parms.andvals));
parms.orvals[cr] = 1 << bit;
on_each_cpu(smp_ctl_bit_callback, &parms, 1);
}
EXPORT_SYMBOL(smp_ctl_set_bit);
/*
* Clear a bit in a control register of all cpus
*/
void smp_ctl_clear_bit(int cr, int bit)
{
struct ec_creg_mask_parms parms;
memset(&parms.orvals, 0, sizeof(parms.orvals));
memset(&parms.andvals, 0xff, sizeof(parms.andvals));
parms.andvals[cr] = ~(1L << bit);
on_each_cpu(smp_ctl_bit_callback, &parms, 1);
}
EXPORT_SYMBOL(smp_ctl_clear_bit);
#ifdef CONFIG_ZFCPDUMP
static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu)
{
if (ipl_info.type != IPL_TYPE_FCP_DUMP)
return;
if (cpu >= NR_CPUS) {
pr_warning("CPU %i exceeds the maximum %i and is excluded from "
"the dump\n", cpu, NR_CPUS - 1);
return;
}
zfcpdump_save_areas[cpu] = kmalloc(sizeof(struct save_area), GFP_KERNEL);
while (raw_sigp(phy_cpu, sigp_stop_and_store_status) == sigp_busy)
cpu_relax();
memcpy_real(zfcpdump_save_areas[cpu],
(void *)(unsigned long) store_prefix() + SAVE_AREA_BASE,
sizeof(struct save_area));
}
struct save_area *zfcpdump_save_areas[NR_CPUS + 1];
EXPORT_SYMBOL_GPL(zfcpdump_save_areas);
#else
static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { }
#endif /* CONFIG_ZFCPDUMP */
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 = cpumask_first(&avail);
if (logical_cpu >= nr_cpu_ids)
return 0;
for (cpu_id = 0; cpu_id <= MAX_CPU_ADDRESS; cpu_id++) {
if (cpu_known(cpu_id))
continue;
__cpu_logical_map[logical_cpu] = cpu_id;
smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
if (!cpu_stopped(logical_cpu))
continue;
cpu_set(logical_cpu, cpu_present_map);
smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
logical_cpu = cpumask_next(logical_cpu, &avail);
if (logical_cpu >= nr_cpu_ids)
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 = cpumask_first(&avail);
if (logical_cpu >= nr_cpu_ids)
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;
smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
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 = cpumask_next(logical_cpu, &avail);
if (logical_cpu >= nr_cpu_ids)
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 = __cpu_logical_map[0];
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 <= MAX_CPU_ADDRESS; cpu++) {
if (cpu == boot_cpu_addr)
continue;
if (!raw_cpu_stopped(cpu))
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;
if (!raw_cpu_stopped(cpu_addr)) {
s_cpus++;
continue;
}
smp_get_save_area(c_cpus, cpu_addr);
c_cpus++;
}
out:
kfree(info);
pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus);
get_online_cpus();
__smp_rescan_cpus();
put_online_cpus();
}
/*
* Activate a secondary processor.
*/
int __cpuinit start_secondary(void *cpuvoid)
{
/* Setup the cpu */
cpu_init();
preempt_disable();
/* Enable TOD clock interrupts on the secondary cpu. */
init_cpu_timer();
/* Enable cpu timer interrupts on the secondary cpu. */
init_cpu_vtimer();
/* Enable pfault pseudo page faults on this cpu. */
pfault_init();
/* call cpu notifiers */
notify_cpu_starting(smp_processor_id());
/* Mark this cpu as online */
ipi_call_lock();
cpu_set(smp_processor_id(), cpu_online_map);
ipi_call_unlock();
/* Switch on interrupts */
local_irq_enable();
/* Print info about this processor */
print_cpu_info();
/* cpu_idle will call schedule for us */
cpu_idle();
return 0;
}
static void __init smp_create_idle(unsigned int cpu)
{
struct task_struct *p;
/*
* don't care about the psw and regs settings since we'll never
* reschedule the forked task.
*/
p = fork_idle(cpu);
if (IS_ERR(p))
panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
current_set[cpu] = p;
}
static int __cpuinit smp_alloc_lowcore(int cpu)
{
unsigned long async_stack, panic_stack;
struct _lowcore *lowcore;
lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER);
if (!lowcore)
return -ENOMEM;
async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
panic_stack = __get_free_page(GFP_KERNEL);
if (!panic_stack || !async_stack)
goto out;
memcpy(lowcore, &S390_lowcore, 512);
memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512);
lowcore->async_stack = async_stack + ASYNC_SIZE;
lowcore->panic_stack = panic_stack + PAGE_SIZE;
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE) {
unsigned long save_area;
save_area = get_zeroed_page(GFP_KERNEL);
if (!save_area)
goto out;
lowcore->extended_save_area_addr = (u32) save_area;
}
#else
if (vdso_alloc_per_cpu(cpu, lowcore))
goto out;
#endif
lowcore_ptr[cpu] = lowcore;
return 0;
out:
free_page(panic_stack);
free_pages(async_stack, ASYNC_ORDER);
free_pages((unsigned long) lowcore, LC_ORDER);
return -ENOMEM;
}
static void smp_free_lowcore(int cpu)
{
struct _lowcore *lowcore;
lowcore = lowcore_ptr[cpu];
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE)
free_page((unsigned long) lowcore->extended_save_area_addr);
#else
vdso_free_per_cpu(cpu, lowcore);
#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;
}
/* Upping and downing of CPUs */
int __cpuinit __cpu_up(unsigned int cpu)
{
struct _lowcore *cpu_lowcore;
struct task_struct *idle;
struct stack_frame *sf;
u32 lowcore;
int ccode;
if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
return -EIO;
if (smp_alloc_lowcore(cpu))
return -ENOMEM;
do {
ccode = sigp(cpu, sigp_initial_cpu_reset);
if (ccode == sigp_busy)
udelay(10);
if (ccode == sigp_not_operational)
goto err_out;
} while (ccode == sigp_busy);
lowcore = (u32)(unsigned long)lowcore_ptr[cpu];
while (sigp_p(lowcore, cpu, sigp_set_prefix) == sigp_busy)
udelay(10);
idle = current_set[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));
memset(sf, 0, sizeof(struct stack_frame));
sf->gprs[9] = (unsigned long) sf;
cpu_lowcore->save_area[15] = (unsigned long) sf;
__ctl_store(cpu_lowcore->cregs_save_area, 0, 15);
atomic_inc(&init_mm.context.attach_count);
asm volatile(
" stam 0,15,0(%0)"
: : "a" (&cpu_lowcore->access_regs_save_area) : "memory");
cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
cpu_lowcore->current_task = (unsigned long) idle;
cpu_lowcore->cpu_nr = cpu;
cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
cpu_lowcore->machine_flags = S390_lowcore.machine_flags;
cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func;
eieio();
while (sigp(cpu, sigp_restart) == sigp_busy)
udelay(10);
while (!cpu_online(cpu))
cpu_relax();
return 0;
err_out:
smp_free_lowcore(cpu);
return -EIO;
}
static int __init setup_possible_cpus(char *s)
{
int pcpus, cpu;
pcpus = simple_strtoul(s, NULL, 0);
init_cpu_possible(cpumask_of(0));
for (cpu = 1; cpu < pcpus && cpu < nr_cpu_ids; cpu++)
set_cpu_possible(cpu, true);
return 0;
}
early_param("possible_cpus", setup_possible_cpus);
#ifdef CONFIG_HOTPLUG_CPU
int __cpu_disable(void)
{
struct ec_creg_mask_parms cr_parms;
int cpu = smp_processor_id();
cpu_clear(cpu, cpu_online_map);
/* Disable pfault pseudo page faults on this cpu. */
pfault_fini();
memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals));
memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals));
/* disable all external interrupts */
cr_parms.orvals[0] = 0;
cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 |
1 << 11 | 1 << 10 | 1 << 6 | 1 << 4);
/* disable all I/O interrupts */
cr_parms.orvals[6] = 0;
cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 |
1 << 27 | 1 << 26 | 1 << 25 | 1 << 24);
/* disable most machine checks */
cr_parms.orvals[14] = 0;
cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 |
1 << 25 | 1 << 24);
smp_ctl_bit_callback(&cr_parms);
return 0;
}
void __cpu_die(unsigned int cpu)
{
/* Wait until target cpu is down */
while (!cpu_stopped(cpu))
cpu_relax();
while (sigp_p(0, cpu, sigp_set_prefix) == sigp_busy)
udelay(10);
smp_free_lowcore(cpu);
atomic_dec(&init_mm.context.attach_count);
pr_info("Processor %d stopped\n", cpu);
}
void cpu_die(void)
{
idle_task_exit();
while (sigp(smp_processor_id(), sigp_stop) == sigp_busy)
cpu_relax();
for (;;);
}
#endif /* CONFIG_HOTPLUG_CPU */
void __init smp_prepare_cpus(unsigned int max_cpus)
{
#ifndef CONFIG_64BIT
unsigned long save_area = 0;
#endif
unsigned long async_stack, panic_stack;
struct _lowcore *lowcore;
unsigned int cpu;
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");
print_cpu_info();
/* Reallocate current lowcore, but keep its contents. */
lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER);
panic_stack = __get_free_page(GFP_KERNEL);
async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
BUG_ON(!lowcore || !panic_stack || !async_stack);
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE)
save_area = get_zeroed_page(GFP_KERNEL);
#endif
local_irq_disable();
local_mcck_disable();
lowcore_ptr[smp_processor_id()] = lowcore;
*lowcore = S390_lowcore;
lowcore->panic_stack = panic_stack + PAGE_SIZE;
lowcore->async_stack = async_stack + ASYNC_SIZE;
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE)
lowcore->extended_save_area_addr = (u32) save_area;
#endif
set_prefix((u32)(unsigned long) lowcore);
local_mcck_enable();
local_irq_enable();
#ifdef CONFIG_64BIT
if (vdso_alloc_per_cpu(smp_processor_id(), &S390_lowcore))
BUG();
#endif
for_each_possible_cpu(cpu)
if (cpu != smp_processor_id())
smp_create_idle(cpu);
}
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;
smp_cpu_polarization[0] = POLARIZATION_UNKNWN;
}
void __init smp_cpus_done(unsigned int max_cpus)
{
}
void __init smp_setup_processor_id(void)
{
S390_lowcore.cpu_nr = 0;
__cpu_logical_map[0] = stap();
}
/*
* the frequency of the profiling timer can be changed
* by writing a multiplier value into /proc/profile.
*
* usually you want to run this on all CPUs ;)
*/
int setup_profiling_timer(unsigned int multiplier)
{
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
static ssize_t cpu_configure_show(struct sys_device *dev,
struct sysdev_attribute *attr, 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,
struct sysdev_attribute *attr,
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;
get_online_cpus();
mutex_lock(&smp_cpu_state_mutex);
rc = -EBUSY;
/* disallow configuration changes of online cpus and cpu 0 */
if (cpu_online(cpu) || cpu == 0)
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;
smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
}
}
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;
smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
}
}
break;
default:
break;
}
out:
mutex_unlock(&smp_cpu_state_mutex);
put_online_cpus();
return rc ? rc : count;
}
static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store);
#endif /* CONFIG_HOTPLUG_CPU */
static ssize_t cpu_polarization_show(struct sys_device *dev,
struct sysdev_attribute *attr, char *buf)
{
int cpu = dev->id;
ssize_t count;
mutex_lock(&smp_cpu_state_mutex);
switch (smp_cpu_polarization[cpu]) {
case POLARIZATION_HRZ:
count = sprintf(buf, "horizontal\n");
break;
case POLARIZATION_VL:
count = sprintf(buf, "vertical:low\n");
break;
case POLARIZATION_VM:
count = sprintf(buf, "vertical:medium\n");
break;
case POLARIZATION_VH:
count = sprintf(buf, "vertical:high\n");
break;
default:
count = sprintf(buf, "unknown\n");
break;
}
mutex_unlock(&smp_cpu_state_mutex);
return count;
}
static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL);
static ssize_t show_cpu_address(struct sys_device *dev,
struct sysdev_attribute *attr, 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,
&attr_polarization.attr,
NULL,
};
static struct attribute_group cpu_common_attr_group = {
.attrs = cpu_common_attrs,
};
static ssize_t show_capability(struct sys_device *dev,
struct sysdev_attribute *attr, char *buf)
{
unsigned int capability;
int rc;
rc = get_cpu_capability(&capability);
if (rc)
return rc;
return sprintf(buf, "%u\n", capability);
}
static SYSDEV_ATTR(capability, 0444, show_capability, NULL);
static ssize_t show_idle_count(struct sys_device *dev,
struct sysdev_attribute *attr, char *buf)
{
struct s390_idle_data *idle;
unsigned long long idle_count;
unsigned int sequence;
idle = &per_cpu(s390_idle, dev->id);
repeat:
sequence = idle->sequence;
smp_rmb();
if (sequence & 1)
goto repeat;
idle_count = idle->idle_count;
if (idle->idle_enter)
idle_count++;
smp_rmb();
if (idle->sequence != sequence)
goto repeat;
return sprintf(buf, "%llu\n", idle_count);
}
static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL);
static ssize_t show_idle_time(struct sys_device *dev,
struct sysdev_attribute *attr, char *buf)
{
struct s390_idle_data *idle;
unsigned long long now, idle_time, idle_enter;
unsigned int sequence;
idle = &per_cpu(s390_idle, dev->id);
now = get_clock();
repeat:
sequence = idle->sequence;
smp_rmb();
if (sequence & 1)
goto repeat;
idle_time = idle->idle_time;
idle_enter = idle->idle_enter;
if (idle_enter != 0ULL && idle_enter < now)
idle_time += now - idle_enter;
smp_rmb();
if (idle->sequence != sequence)
goto repeat;
return sprintf(buf, "%llu\n", idle_time >> 12);
}
static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL);
static struct attribute *cpu_online_attrs[] = {
&attr_capability.attr,
&attr_idle_count.attr,
&attr_idle_time_us.attr,
NULL,
};
static struct attribute_group cpu_online_attr_group = {
.attrs = cpu_online_attrs,
};
static int __cpuinit smp_cpu_notify(struct notifier_block *self,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned int)(long)hcpu;
struct cpu *c = &per_cpu(cpu_devices, cpu);
struct sys_device *s = &c->sysdev;
struct s390_idle_data *idle;
int err = 0;
switch (action) {
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
idle = &per_cpu(s390_idle, cpu);
memset(idle, 0, sizeof(struct s390_idle_data));
err = sysfs_create_group(&s->kobj, &cpu_online_attr_group);
break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
sysfs_remove_group(&s->kobj, &cpu_online_attr_group);
break;
}
return notifier_from_errno(err);
}
static struct notifier_block __cpuinitdata smp_cpu_nb = {
.notifier_call = smp_cpu_notify,
};
static int __devinit 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
int __ref smp_rescan_cpus(void)
{
cpumask_t newcpus;
int cpu;
int rc;
get_online_cpus();
mutex_lock(&smp_cpu_state_mutex);
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:
mutex_unlock(&smp_cpu_state_mutex);
put_online_cpus();
if (!cpus_empty(newcpus))
topology_schedule_update();
return rc;
}
static ssize_t __ref rescan_store(struct sysdev_class *class,
struct sysdev_class_attribute *attr,
const char *buf,
size_t count)
{
int rc;
rc = smp_rescan_cpus();
return rc ? rc : count;
}
static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store);
#endif /* CONFIG_HOTPLUG_CPU */
static ssize_t dispatching_show(struct sysdev_class *class,
struct sysdev_class_attribute *attr,
char *buf)
{
ssize_t count;
mutex_lock(&smp_cpu_state_mutex);
count = sprintf(buf, "%d\n", cpu_management);
mutex_unlock(&smp_cpu_state_mutex);
return count;
}
static ssize_t dispatching_store(struct sysdev_class *dev,
struct sysdev_class_attribute *attr,
const char *buf,
size_t count)
{
int val, rc;
char delim;
if (sscanf(buf, "%d %c", &val, &delim) != 1)
return -EINVAL;
if (val != 0 && val != 1)
return -EINVAL;
rc = 0;
get_online_cpus();
mutex_lock(&smp_cpu_state_mutex);
if (cpu_management == val)
goto out;
rc = topology_set_cpu_management(val);
if (!rc)
cpu_management = val;
out:
mutex_unlock(&smp_cpu_state_mutex);
put_online_cpus();
return rc ? rc : count;
}
static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show,
dispatching_store);
static int __init topology_init(void)
{
int cpu;
int rc;
register_cpu_notifier(&smp_cpu_nb);
#ifdef CONFIG_HOTPLUG_CPU
rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan);
if (rc)
return rc;
#endif
rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching);
if (rc)
return rc;
for_each_present_cpu(cpu) {
rc = smp_add_present_cpu(cpu);
if (rc)
return rc;
}
return 0;
}
subsys_initcall(topology_init);