2 * arch/s390/kernel/smp.c
4 * Copyright IBM Corp. 1999,2007
5 * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
6 * Martin Schwidefsky (schwidefsky@de.ibm.com)
7 * Heiko Carstens (heiko.carstens@de.ibm.com)
9 * based on other smp stuff by
10 * (c) 1995 Alan Cox, CymruNET Ltd <alan@cymru.net>
11 * (c) 1998 Ingo Molnar
13 * We work with logical cpu numbering everywhere we can. The only
14 * functions using the real cpu address (got from STAP) are the sigp
15 * functions. For all other functions we use the identity mapping.
16 * That means that cpu_number_map[i] == i for every cpu. cpu_number_map is
17 * used e.g. to find the idle task belonging to a logical cpu. Every array
18 * in the kernel is sorted by the logical cpu number and not by the physical
19 * one which is causing all the confusion with __cpu_logical_map and
20 * cpu_number_map in other architectures.
23 #define KMSG_COMPONENT "cpu"
24 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
26 #include <linux/module.h>
27 #include <linux/init.h>
29 #include <linux/err.h>
30 #include <linux/spinlock.h>
31 #include <linux/kernel_stat.h>
32 #include <linux/delay.h>
33 #include <linux/cache.h>
34 #include <linux/interrupt.h>
35 #include <linux/cpu.h>
36 #include <linux/timex.h>
37 #include <linux/bootmem.h>
39 #include <asm/setup.h>
41 #include <asm/pgalloc.h>
43 #include <asm/s390_ext.h>
44 #include <asm/cpcmd.h>
45 #include <asm/tlbflush.h>
46 #include <asm/timer.h>
47 #include <asm/lowcore.h>
53 * An array with a pointer the lowcore of every CPU.
55 struct _lowcore *lowcore_ptr[NR_CPUS];
56 EXPORT_SYMBOL(lowcore_ptr);
58 static struct task_struct *current_set[NR_CPUS];
60 static u8 smp_cpu_type;
61 static int smp_use_sigp_detection;
68 DEFINE_MUTEX(smp_cpu_state_mutex);
69 int smp_cpu_polarization[NR_CPUS];
70 static int smp_cpu_state[NR_CPUS];
71 static int cpu_management;
73 static DEFINE_PER_CPU(struct cpu, cpu_devices);
75 static void smp_ext_bitcall(int, ec_bit_sig);
77 void smp_send_stop(void)
81 /* Disable all interrupts/machine checks */
82 __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
84 /* write magic number to zero page (absolute 0) */
85 lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
87 /* stop all processors */
88 for_each_online_cpu(cpu) {
89 if (cpu == smp_processor_id())
92 rc = signal_processor(cpu, sigp_stop);
93 } while (rc == sigp_busy);
95 while (!smp_cpu_not_running(cpu))
101 * This is the main routine where commands issued by other
105 static void do_ext_call_interrupt(__u16 code)
110 * handle bit signal external calls
112 * For the ec_schedule signal we have to do nothing. All the work
113 * is done automatically when we return from the interrupt.
115 bits = xchg(&S390_lowcore.ext_call_fast, 0);
117 if (test_bit(ec_call_function, &bits))
118 generic_smp_call_function_interrupt();
120 if (test_bit(ec_call_function_single, &bits))
121 generic_smp_call_function_single_interrupt();
125 * Send an external call sigp to another cpu and return without waiting
126 * for its completion.
128 static void smp_ext_bitcall(int cpu, ec_bit_sig sig)
131 * Set signaling bit in lowcore of target cpu and kick it
133 set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast);
134 while (signal_processor(cpu, sigp_emergency_signal) == sigp_busy)
138 void arch_send_call_function_ipi(cpumask_t mask)
142 for_each_cpu_mask(cpu, mask)
143 smp_ext_bitcall(cpu, ec_call_function);
146 void arch_send_call_function_single_ipi(int cpu)
148 smp_ext_bitcall(cpu, ec_call_function_single);
153 * this function sends a 'purge tlb' signal to another CPU.
155 static void smp_ptlb_callback(void *info)
160 void smp_ptlb_all(void)
162 on_each_cpu(smp_ptlb_callback, NULL, 1);
164 EXPORT_SYMBOL(smp_ptlb_all);
165 #endif /* ! CONFIG_64BIT */
168 * this function sends a 'reschedule' IPI to another CPU.
169 * it goes straight through and wastes no time serializing
170 * anything. Worst case is that we lose a reschedule ...
172 void smp_send_reschedule(int cpu)
174 smp_ext_bitcall(cpu, ec_schedule);
178 * parameter area for the set/clear control bit callbacks
180 struct ec_creg_mask_parms {
181 unsigned long orvals[16];
182 unsigned long andvals[16];
186 * callback for setting/clearing control bits
188 static void smp_ctl_bit_callback(void *info)
190 struct ec_creg_mask_parms *pp = info;
191 unsigned long cregs[16];
194 __ctl_store(cregs, 0, 15);
195 for (i = 0; i <= 15; i++)
196 cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i];
197 __ctl_load(cregs, 0, 15);
201 * Set a bit in a control register of all cpus
203 void smp_ctl_set_bit(int cr, int bit)
205 struct ec_creg_mask_parms parms;
207 memset(&parms.orvals, 0, sizeof(parms.orvals));
208 memset(&parms.andvals, 0xff, sizeof(parms.andvals));
209 parms.orvals[cr] = 1 << bit;
210 on_each_cpu(smp_ctl_bit_callback, &parms, 1);
212 EXPORT_SYMBOL(smp_ctl_set_bit);
215 * Clear a bit in a control register of all cpus
217 void smp_ctl_clear_bit(int cr, int bit)
219 struct ec_creg_mask_parms parms;
221 memset(&parms.orvals, 0, sizeof(parms.orvals));
222 memset(&parms.andvals, 0xff, sizeof(parms.andvals));
223 parms.andvals[cr] = ~(1L << bit);
224 on_each_cpu(smp_ctl_bit_callback, &parms, 1);
226 EXPORT_SYMBOL(smp_ctl_clear_bit);
229 * In early ipl state a temp. logically cpu number is needed, so the sigp
230 * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on
231 * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1.
233 #define CPU_INIT_NO 1
235 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
238 * zfcpdump_prefix_array holds prefix registers for the following scenario:
239 * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to
240 * save its prefix registers, since they get lost, when switching from 31 bit
243 unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \
244 __attribute__((__section__(".data")));
246 static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu)
248 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
250 if (cpu >= NR_CPUS) {
251 pr_warning("CPU %i exceeds the maximum %i and is excluded from "
252 "the dump\n", cpu, NR_CPUS - 1);
255 zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL);
256 __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu;
257 while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) ==
260 memcpy(zfcpdump_save_areas[cpu],
261 (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE,
264 /* copy original prefix register */
265 zfcpdump_save_areas[cpu]->s390x.pref_reg = zfcpdump_prefix_array[cpu];
269 union save_area *zfcpdump_save_areas[NR_CPUS + 1];
270 EXPORT_SYMBOL_GPL(zfcpdump_save_areas);
274 static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { }
276 #endif /* CONFIG_ZFCPDUMP || CONFIG_ZFCPDUMP_MODULE */
278 static int cpu_stopped(int cpu)
282 /* Check for stopped state */
283 if (signal_processor_ps(&status, 0, cpu, sigp_sense) ==
284 sigp_status_stored) {
291 static int cpu_known(int cpu_id)
295 for_each_present_cpu(cpu) {
296 if (__cpu_logical_map[cpu] == cpu_id)
302 static int smp_rescan_cpus_sigp(cpumask_t avail)
304 int cpu_id, logical_cpu;
306 logical_cpu = first_cpu(avail);
307 if (logical_cpu == NR_CPUS)
309 for (cpu_id = 0; cpu_id <= 65535; cpu_id++) {
310 if (cpu_known(cpu_id))
312 __cpu_logical_map[logical_cpu] = cpu_id;
313 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
314 if (!cpu_stopped(logical_cpu))
316 cpu_set(logical_cpu, cpu_present_map);
317 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
318 logical_cpu = next_cpu(logical_cpu, avail);
319 if (logical_cpu == NR_CPUS)
325 static int smp_rescan_cpus_sclp(cpumask_t avail)
327 struct sclp_cpu_info *info;
328 int cpu_id, logical_cpu, cpu;
331 logical_cpu = first_cpu(avail);
332 if (logical_cpu == NR_CPUS)
334 info = kmalloc(sizeof(*info), GFP_KERNEL);
337 rc = sclp_get_cpu_info(info);
340 for (cpu = 0; cpu < info->combined; cpu++) {
341 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
343 cpu_id = info->cpu[cpu].address;
344 if (cpu_known(cpu_id))
346 __cpu_logical_map[logical_cpu] = cpu_id;
347 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
348 cpu_set(logical_cpu, cpu_present_map);
349 if (cpu >= info->configured)
350 smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY;
352 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
353 logical_cpu = next_cpu(logical_cpu, avail);
354 if (logical_cpu == NR_CPUS)
362 static int __smp_rescan_cpus(void)
366 cpus_xor(avail, cpu_possible_map, cpu_present_map);
367 if (smp_use_sigp_detection)
368 return smp_rescan_cpus_sigp(avail);
370 return smp_rescan_cpus_sclp(avail);
373 static void __init smp_detect_cpus(void)
375 unsigned int cpu, c_cpus, s_cpus;
376 struct sclp_cpu_info *info;
377 u16 boot_cpu_addr, cpu_addr;
381 boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
382 info = kmalloc(sizeof(*info), GFP_KERNEL);
384 panic("smp_detect_cpus failed to allocate memory\n");
385 /* Use sigp detection algorithm if sclp doesn't work. */
386 if (sclp_get_cpu_info(info)) {
387 smp_use_sigp_detection = 1;
388 for (cpu = 0; cpu <= 65535; cpu++) {
389 if (cpu == boot_cpu_addr)
391 __cpu_logical_map[CPU_INIT_NO] = cpu;
392 if (!cpu_stopped(CPU_INIT_NO))
394 smp_get_save_area(c_cpus, cpu);
400 if (info->has_cpu_type) {
401 for (cpu = 0; cpu < info->combined; cpu++) {
402 if (info->cpu[cpu].address == boot_cpu_addr) {
403 smp_cpu_type = info->cpu[cpu].type;
409 for (cpu = 0; cpu < info->combined; cpu++) {
410 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
412 cpu_addr = info->cpu[cpu].address;
413 if (cpu_addr == boot_cpu_addr)
415 __cpu_logical_map[CPU_INIT_NO] = cpu_addr;
416 if (!cpu_stopped(CPU_INIT_NO)) {
420 smp_get_save_area(c_cpus, cpu_addr);
425 pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus);
432 * Activate a secondary processor.
434 int __cpuinit start_secondary(void *cpuvoid)
439 /* Enable TOD clock interrupts on the secondary cpu. */
441 /* Enable cpu timer interrupts on the secondary cpu. */
443 /* Enable pfault pseudo page faults on this cpu. */
446 /* call cpu notifiers */
447 notify_cpu_starting(smp_processor_id());
448 /* Mark this cpu as online */
450 cpu_set(smp_processor_id(), cpu_online_map);
452 /* Switch on interrupts */
454 /* Print info about this processor */
455 print_cpu_info(&S390_lowcore.cpu_data);
456 /* cpu_idle will call schedule for us */
461 static void __init smp_create_idle(unsigned int cpu)
463 struct task_struct *p;
466 * don't care about the psw and regs settings since we'll never
467 * reschedule the forked task.
471 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
472 current_set[cpu] = p;
475 static int __cpuinit smp_alloc_lowcore(int cpu)
477 unsigned long async_stack, panic_stack;
478 struct _lowcore *lowcore;
481 lc_order = sizeof(long) == 8 ? 1 : 0;
482 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
485 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
486 panic_stack = __get_free_page(GFP_KERNEL);
487 if (!panic_stack || !async_stack)
489 memcpy(lowcore, &S390_lowcore, 512);
490 memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512);
491 lowcore->async_stack = async_stack + ASYNC_SIZE;
492 lowcore->panic_stack = panic_stack + PAGE_SIZE;
495 if (MACHINE_HAS_IEEE) {
496 unsigned long save_area;
498 save_area = get_zeroed_page(GFP_KERNEL);
501 lowcore->extended_save_area_addr = (u32) save_area;
504 lowcore_ptr[cpu] = lowcore;
508 free_page(panic_stack);
509 free_pages(async_stack, ASYNC_ORDER);
510 free_pages((unsigned long) lowcore, lc_order);
514 #ifdef CONFIG_HOTPLUG_CPU
515 static void smp_free_lowcore(int cpu)
517 struct _lowcore *lowcore;
520 lc_order = sizeof(long) == 8 ? 1 : 0;
521 lowcore = lowcore_ptr[cpu];
523 if (MACHINE_HAS_IEEE)
524 free_page((unsigned long) lowcore->extended_save_area_addr);
526 free_page(lowcore->panic_stack - PAGE_SIZE);
527 free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER);
528 free_pages((unsigned long) lowcore, lc_order);
529 lowcore_ptr[cpu] = NULL;
531 #endif /* CONFIG_HOTPLUG_CPU */
533 /* Upping and downing of CPUs */
534 int __cpuinit __cpu_up(unsigned int cpu)
536 struct task_struct *idle;
537 struct _lowcore *cpu_lowcore;
538 struct stack_frame *sf;
541 if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
543 if (smp_alloc_lowcore(cpu))
546 ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
547 cpu, sigp_set_prefix);
551 idle = current_set[cpu];
552 cpu_lowcore = lowcore_ptr[cpu];
553 cpu_lowcore->kernel_stack = (unsigned long)
554 task_stack_page(idle) + THREAD_SIZE;
555 cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle);
556 sf = (struct stack_frame *) (cpu_lowcore->kernel_stack
557 - sizeof(struct pt_regs)
558 - sizeof(struct stack_frame));
559 memset(sf, 0, sizeof(struct stack_frame));
560 sf->gprs[9] = (unsigned long) sf;
561 cpu_lowcore->save_area[15] = (unsigned long) sf;
562 __ctl_store(cpu_lowcore->cregs_save_area, 0, 15);
565 : : "a" (&cpu_lowcore->access_regs_save_area) : "memory");
566 cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
567 cpu_lowcore->current_task = (unsigned long) idle;
568 cpu_lowcore->cpu_data.cpu_nr = cpu;
569 cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
570 cpu_lowcore->ipl_device = S390_lowcore.ipl_device;
573 while (signal_processor(cpu, sigp_restart) == sigp_busy)
576 while (!cpu_online(cpu))
581 static int __init setup_possible_cpus(char *s)
585 pcpus = simple_strtoul(s, NULL, 0);
586 cpu_possible_map = cpumask_of_cpu(0);
587 for (cpu = 1; cpu < pcpus && cpu < NR_CPUS; cpu++)
588 cpu_set(cpu, cpu_possible_map);
591 early_param("possible_cpus", setup_possible_cpus);
593 #ifdef CONFIG_HOTPLUG_CPU
595 int __cpu_disable(void)
597 struct ec_creg_mask_parms cr_parms;
598 int cpu = smp_processor_id();
600 cpu_clear(cpu, cpu_online_map);
602 /* Disable pfault pseudo page faults on this cpu. */
605 memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals));
606 memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals));
608 /* disable all external interrupts */
609 cr_parms.orvals[0] = 0;
610 cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 |
611 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4);
612 /* disable all I/O interrupts */
613 cr_parms.orvals[6] = 0;
614 cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 |
615 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24);
616 /* disable most machine checks */
617 cr_parms.orvals[14] = 0;
618 cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 |
621 smp_ctl_bit_callback(&cr_parms);
626 void __cpu_die(unsigned int cpu)
628 /* Wait until target cpu is down */
629 while (!smp_cpu_not_running(cpu))
631 smp_free_lowcore(cpu);
632 pr_info("Processor %d stopped\n", cpu);
638 signal_processor(smp_processor_id(), sigp_stop);
643 #endif /* CONFIG_HOTPLUG_CPU */
645 void __init smp_prepare_cpus(unsigned int max_cpus)
648 unsigned long save_area = 0;
650 unsigned long async_stack, panic_stack;
651 struct _lowcore *lowcore;
657 /* request the 0x1201 emergency signal external interrupt */
658 if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
659 panic("Couldn't request external interrupt 0x1201");
660 print_cpu_info(&S390_lowcore.cpu_data);
662 /* Reallocate current lowcore, but keep its contents. */
663 lc_order = sizeof(long) == 8 ? 1 : 0;
664 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
665 panic_stack = __get_free_page(GFP_KERNEL);
666 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
668 if (MACHINE_HAS_IEEE)
669 save_area = get_zeroed_page(GFP_KERNEL);
672 local_mcck_disable();
673 lowcore_ptr[smp_processor_id()] = lowcore;
674 *lowcore = S390_lowcore;
675 lowcore->panic_stack = panic_stack + PAGE_SIZE;
676 lowcore->async_stack = async_stack + ASYNC_SIZE;
678 if (MACHINE_HAS_IEEE)
679 lowcore->extended_save_area_addr = (u32) save_area;
681 set_prefix((u32)(unsigned long) lowcore);
684 for_each_possible_cpu(cpu)
685 if (cpu != smp_processor_id())
686 smp_create_idle(cpu);
689 void __init smp_prepare_boot_cpu(void)
691 BUG_ON(smp_processor_id() != 0);
693 current_thread_info()->cpu = 0;
694 cpu_set(0, cpu_present_map);
695 cpu_set(0, cpu_online_map);
696 S390_lowcore.percpu_offset = __per_cpu_offset[0];
697 current_set[0] = current;
698 smp_cpu_state[0] = CPU_STATE_CONFIGURED;
699 smp_cpu_polarization[0] = POLARIZATION_UNKNWN;
702 void __init smp_cpus_done(unsigned int max_cpus)
707 * the frequency of the profiling timer can be changed
708 * by writing a multiplier value into /proc/profile.
710 * usually you want to run this on all CPUs ;)
712 int setup_profiling_timer(unsigned int multiplier)
717 #ifdef CONFIG_HOTPLUG_CPU
718 static ssize_t cpu_configure_show(struct sys_device *dev,
719 struct sysdev_attribute *attr, char *buf)
723 mutex_lock(&smp_cpu_state_mutex);
724 count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]);
725 mutex_unlock(&smp_cpu_state_mutex);
729 static ssize_t cpu_configure_store(struct sys_device *dev,
730 struct sysdev_attribute *attr,
731 const char *buf, size_t count)
737 if (sscanf(buf, "%d %c", &val, &delim) != 1)
739 if (val != 0 && val != 1)
743 mutex_lock(&smp_cpu_state_mutex);
750 if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) {
751 rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]);
753 smp_cpu_state[cpu] = CPU_STATE_STANDBY;
754 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
759 if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) {
760 rc = sclp_cpu_configure(__cpu_logical_map[cpu]);
762 smp_cpu_state[cpu] = CPU_STATE_CONFIGURED;
763 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
771 mutex_unlock(&smp_cpu_state_mutex);
773 return rc ? rc : count;
775 static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store);
776 #endif /* CONFIG_HOTPLUG_CPU */
778 static ssize_t cpu_polarization_show(struct sys_device *dev,
779 struct sysdev_attribute *attr, char *buf)
784 mutex_lock(&smp_cpu_state_mutex);
785 switch (smp_cpu_polarization[cpu]) {
786 case POLARIZATION_HRZ:
787 count = sprintf(buf, "horizontal\n");
789 case POLARIZATION_VL:
790 count = sprintf(buf, "vertical:low\n");
792 case POLARIZATION_VM:
793 count = sprintf(buf, "vertical:medium\n");
795 case POLARIZATION_VH:
796 count = sprintf(buf, "vertical:high\n");
799 count = sprintf(buf, "unknown\n");
802 mutex_unlock(&smp_cpu_state_mutex);
805 static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL);
807 static ssize_t show_cpu_address(struct sys_device *dev,
808 struct sysdev_attribute *attr, char *buf)
810 return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]);
812 static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL);
815 static struct attribute *cpu_common_attrs[] = {
816 #ifdef CONFIG_HOTPLUG_CPU
817 &attr_configure.attr,
820 &attr_polarization.attr,
824 static struct attribute_group cpu_common_attr_group = {
825 .attrs = cpu_common_attrs,
828 static ssize_t show_capability(struct sys_device *dev,
829 struct sysdev_attribute *attr, char *buf)
831 unsigned int capability;
834 rc = get_cpu_capability(&capability);
837 return sprintf(buf, "%u\n", capability);
839 static SYSDEV_ATTR(capability, 0444, show_capability, NULL);
841 static ssize_t show_idle_count(struct sys_device *dev,
842 struct sysdev_attribute *attr, char *buf)
844 struct s390_idle_data *idle;
845 unsigned long long idle_count;
847 idle = &per_cpu(s390_idle, dev->id);
848 spin_lock_irq(&idle->lock);
849 idle_count = idle->idle_count;
850 spin_unlock_irq(&idle->lock);
851 return sprintf(buf, "%llu\n", idle_count);
853 static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL);
855 static ssize_t show_idle_time(struct sys_device *dev,
856 struct sysdev_attribute *attr, char *buf)
858 struct s390_idle_data *idle;
859 unsigned long long new_time;
861 idle = &per_cpu(s390_idle, dev->id);
862 spin_lock_irq(&idle->lock);
864 new_time = get_clock();
865 idle->idle_time += new_time - idle->idle_enter;
866 idle->idle_enter = new_time;
868 new_time = idle->idle_time;
869 spin_unlock_irq(&idle->lock);
870 return sprintf(buf, "%llu\n", new_time >> 12);
872 static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL);
874 static struct attribute *cpu_online_attrs[] = {
875 &attr_capability.attr,
876 &attr_idle_count.attr,
877 &attr_idle_time_us.attr,
881 static struct attribute_group cpu_online_attr_group = {
882 .attrs = cpu_online_attrs,
885 static int __cpuinit smp_cpu_notify(struct notifier_block *self,
886 unsigned long action, void *hcpu)
888 unsigned int cpu = (unsigned int)(long)hcpu;
889 struct cpu *c = &per_cpu(cpu_devices, cpu);
890 struct sys_device *s = &c->sysdev;
891 struct s390_idle_data *idle;
895 case CPU_ONLINE_FROZEN:
896 idle = &per_cpu(s390_idle, cpu);
897 spin_lock_irq(&idle->lock);
898 idle->idle_enter = 0;
900 idle->idle_count = 0;
901 spin_unlock_irq(&idle->lock);
902 if (sysfs_create_group(&s->kobj, &cpu_online_attr_group))
906 case CPU_DEAD_FROZEN:
907 sysfs_remove_group(&s->kobj, &cpu_online_attr_group);
913 static struct notifier_block __cpuinitdata smp_cpu_nb = {
914 .notifier_call = smp_cpu_notify,
917 static int __devinit smp_add_present_cpu(int cpu)
919 struct cpu *c = &per_cpu(cpu_devices, cpu);
920 struct sys_device *s = &c->sysdev;
924 rc = register_cpu(c, cpu);
927 rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group);
930 if (!cpu_online(cpu))
932 rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group);
935 sysfs_remove_group(&s->kobj, &cpu_common_attr_group);
937 #ifdef CONFIG_HOTPLUG_CPU
944 #ifdef CONFIG_HOTPLUG_CPU
946 int __ref smp_rescan_cpus(void)
953 mutex_lock(&smp_cpu_state_mutex);
954 newcpus = cpu_present_map;
955 rc = __smp_rescan_cpus();
958 cpus_andnot(newcpus, cpu_present_map, newcpus);
959 for_each_cpu_mask(cpu, newcpus) {
960 rc = smp_add_present_cpu(cpu);
962 cpu_clear(cpu, cpu_present_map);
966 mutex_unlock(&smp_cpu_state_mutex);
968 if (!cpus_empty(newcpus))
969 topology_schedule_update();
973 static ssize_t __ref rescan_store(struct sysdev_class *class, const char *buf,
978 rc = smp_rescan_cpus();
979 return rc ? rc : count;
981 static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store);
982 #endif /* CONFIG_HOTPLUG_CPU */
984 static ssize_t dispatching_show(struct sysdev_class *class, char *buf)
988 mutex_lock(&smp_cpu_state_mutex);
989 count = sprintf(buf, "%d\n", cpu_management);
990 mutex_unlock(&smp_cpu_state_mutex);
994 static ssize_t dispatching_store(struct sysdev_class *dev, const char *buf,
1000 if (sscanf(buf, "%d %c", &val, &delim) != 1)
1002 if (val != 0 && val != 1)
1006 mutex_lock(&smp_cpu_state_mutex);
1007 if (cpu_management == val)
1009 rc = topology_set_cpu_management(val);
1011 cpu_management = val;
1013 mutex_unlock(&smp_cpu_state_mutex);
1015 return rc ? rc : count;
1017 static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show,
1020 static int __init topology_init(void)
1025 register_cpu_notifier(&smp_cpu_nb);
1027 #ifdef CONFIG_HOTPLUG_CPU
1028 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan);
1032 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching);
1035 for_each_present_cpu(cpu) {
1036 rc = smp_add_present_cpu(cpu);
1042 subsys_initcall(topology_init);