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 cpumask_t cpu_online_map = CPU_MASK_NONE;
59 EXPORT_SYMBOL(cpu_online_map);
61 cpumask_t cpu_possible_map = CPU_MASK_ALL;
62 EXPORT_SYMBOL(cpu_possible_map);
64 static struct task_struct *current_set[NR_CPUS];
66 static u8 smp_cpu_type;
67 static int smp_use_sigp_detection;
74 DEFINE_MUTEX(smp_cpu_state_mutex);
75 int smp_cpu_polarization[NR_CPUS];
76 static int smp_cpu_state[NR_CPUS];
77 static int cpu_management;
79 static DEFINE_PER_CPU(struct cpu, cpu_devices);
81 static void smp_ext_bitcall(int, ec_bit_sig);
83 void smp_send_stop(void)
87 /* Disable all interrupts/machine checks */
88 __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
90 /* write magic number to zero page (absolute 0) */
91 lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
93 /* stop all processors */
94 for_each_online_cpu(cpu) {
95 if (cpu == smp_processor_id())
98 rc = signal_processor(cpu, sigp_stop);
99 } while (rc == sigp_busy);
101 while (!smp_cpu_not_running(cpu))
107 * This is the main routine where commands issued by other
111 static void do_ext_call_interrupt(__u16 code)
116 * handle bit signal external calls
118 * For the ec_schedule signal we have to do nothing. All the work
119 * is done automatically when we return from the interrupt.
121 bits = xchg(&S390_lowcore.ext_call_fast, 0);
123 if (test_bit(ec_call_function, &bits))
124 generic_smp_call_function_interrupt();
126 if (test_bit(ec_call_function_single, &bits))
127 generic_smp_call_function_single_interrupt();
131 * Send an external call sigp to another cpu and return without waiting
132 * for its completion.
134 static void smp_ext_bitcall(int cpu, ec_bit_sig sig)
137 * Set signaling bit in lowcore of target cpu and kick it
139 set_bit(sig, (unsigned long *) &lowcore_ptr[cpu]->ext_call_fast);
140 while (signal_processor(cpu, sigp_emergency_signal) == sigp_busy)
144 void arch_send_call_function_ipi(cpumask_t mask)
148 for_each_cpu_mask(cpu, mask)
149 smp_ext_bitcall(cpu, ec_call_function);
152 void arch_send_call_function_single_ipi(int cpu)
154 smp_ext_bitcall(cpu, ec_call_function_single);
159 * this function sends a 'purge tlb' signal to another CPU.
161 static void smp_ptlb_callback(void *info)
166 void smp_ptlb_all(void)
168 on_each_cpu(smp_ptlb_callback, NULL, 1);
170 EXPORT_SYMBOL(smp_ptlb_all);
171 #endif /* ! CONFIG_64BIT */
174 * this function sends a 'reschedule' IPI to another CPU.
175 * it goes straight through and wastes no time serializing
176 * anything. Worst case is that we lose a reschedule ...
178 void smp_send_reschedule(int cpu)
180 smp_ext_bitcall(cpu, ec_schedule);
184 * parameter area for the set/clear control bit callbacks
186 struct ec_creg_mask_parms {
187 unsigned long orvals[16];
188 unsigned long andvals[16];
192 * callback for setting/clearing control bits
194 static void smp_ctl_bit_callback(void *info)
196 struct ec_creg_mask_parms *pp = info;
197 unsigned long cregs[16];
200 __ctl_store(cregs, 0, 15);
201 for (i = 0; i <= 15; i++)
202 cregs[i] = (cregs[i] & pp->andvals[i]) | pp->orvals[i];
203 __ctl_load(cregs, 0, 15);
207 * Set a bit in a control register of all cpus
209 void smp_ctl_set_bit(int cr, int bit)
211 struct ec_creg_mask_parms parms;
213 memset(&parms.orvals, 0, sizeof(parms.orvals));
214 memset(&parms.andvals, 0xff, sizeof(parms.andvals));
215 parms.orvals[cr] = 1 << bit;
216 on_each_cpu(smp_ctl_bit_callback, &parms, 1);
218 EXPORT_SYMBOL(smp_ctl_set_bit);
221 * Clear a bit in a control register of all cpus
223 void smp_ctl_clear_bit(int cr, int bit)
225 struct ec_creg_mask_parms parms;
227 memset(&parms.orvals, 0, sizeof(parms.orvals));
228 memset(&parms.andvals, 0xff, sizeof(parms.andvals));
229 parms.andvals[cr] = ~(1L << bit);
230 on_each_cpu(smp_ctl_bit_callback, &parms, 1);
232 EXPORT_SYMBOL(smp_ctl_clear_bit);
235 * In early ipl state a temp. logically cpu number is needed, so the sigp
236 * functions can be used to sense other cpus. Since NR_CPUS is >= 2 on
237 * CONFIG_SMP and the ipl cpu is logical cpu 0, it must be 1.
239 #define CPU_INIT_NO 1
241 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
244 * zfcpdump_prefix_array holds prefix registers for the following scenario:
245 * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to
246 * save its prefix registers, since they get lost, when switching from 31 bit
249 unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \
250 __attribute__((__section__(".data")));
252 static void __init smp_get_save_area(unsigned int cpu, unsigned int phy_cpu)
254 if (ipl_info.type != IPL_TYPE_FCP_DUMP)
256 if (cpu >= NR_CPUS) {
257 pr_warning("CPU %i exceeds the maximum %i and is excluded from "
258 "the dump\n", cpu, NR_CPUS - 1);
261 zfcpdump_save_areas[cpu] = kmalloc(sizeof(union save_area), GFP_KERNEL);
262 __cpu_logical_map[CPU_INIT_NO] = (__u16) phy_cpu;
263 while (signal_processor(CPU_INIT_NO, sigp_stop_and_store_status) ==
266 memcpy(zfcpdump_save_areas[cpu],
267 (void *)(unsigned long) store_prefix() + SAVE_AREA_BASE,
270 /* copy original prefix register */
271 zfcpdump_save_areas[cpu]->s390x.pref_reg = zfcpdump_prefix_array[cpu];
275 union save_area *zfcpdump_save_areas[NR_CPUS + 1];
276 EXPORT_SYMBOL_GPL(zfcpdump_save_areas);
280 static inline void smp_get_save_area(unsigned int cpu, unsigned int phy_cpu) { }
282 #endif /* CONFIG_ZFCPDUMP || CONFIG_ZFCPDUMP_MODULE */
284 static int cpu_stopped(int cpu)
288 /* Check for stopped state */
289 if (signal_processor_ps(&status, 0, cpu, sigp_sense) ==
290 sigp_status_stored) {
297 static int cpu_known(int cpu_id)
301 for_each_present_cpu(cpu) {
302 if (__cpu_logical_map[cpu] == cpu_id)
308 static int smp_rescan_cpus_sigp(cpumask_t avail)
310 int cpu_id, logical_cpu;
312 logical_cpu = first_cpu(avail);
313 if (logical_cpu == NR_CPUS)
315 for (cpu_id = 0; cpu_id <= 65535; cpu_id++) {
316 if (cpu_known(cpu_id))
318 __cpu_logical_map[logical_cpu] = cpu_id;
319 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
320 if (!cpu_stopped(logical_cpu))
322 cpu_set(logical_cpu, cpu_present_map);
323 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
324 logical_cpu = next_cpu(logical_cpu, avail);
325 if (logical_cpu == NR_CPUS)
331 static int smp_rescan_cpus_sclp(cpumask_t avail)
333 struct sclp_cpu_info *info;
334 int cpu_id, logical_cpu, cpu;
337 logical_cpu = first_cpu(avail);
338 if (logical_cpu == NR_CPUS)
340 info = kmalloc(sizeof(*info), GFP_KERNEL);
343 rc = sclp_get_cpu_info(info);
346 for (cpu = 0; cpu < info->combined; cpu++) {
347 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
349 cpu_id = info->cpu[cpu].address;
350 if (cpu_known(cpu_id))
352 __cpu_logical_map[logical_cpu] = cpu_id;
353 smp_cpu_polarization[logical_cpu] = POLARIZATION_UNKNWN;
354 cpu_set(logical_cpu, cpu_present_map);
355 if (cpu >= info->configured)
356 smp_cpu_state[logical_cpu] = CPU_STATE_STANDBY;
358 smp_cpu_state[logical_cpu] = CPU_STATE_CONFIGURED;
359 logical_cpu = next_cpu(logical_cpu, avail);
360 if (logical_cpu == NR_CPUS)
368 static int __smp_rescan_cpus(void)
372 cpus_xor(avail, cpu_possible_map, cpu_present_map);
373 if (smp_use_sigp_detection)
374 return smp_rescan_cpus_sigp(avail);
376 return smp_rescan_cpus_sclp(avail);
379 static void __init smp_detect_cpus(void)
381 unsigned int cpu, c_cpus, s_cpus;
382 struct sclp_cpu_info *info;
383 u16 boot_cpu_addr, cpu_addr;
387 boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
388 info = kmalloc(sizeof(*info), GFP_KERNEL);
390 panic("smp_detect_cpus failed to allocate memory\n");
391 /* Use sigp detection algorithm if sclp doesn't work. */
392 if (sclp_get_cpu_info(info)) {
393 smp_use_sigp_detection = 1;
394 for (cpu = 0; cpu <= 65535; cpu++) {
395 if (cpu == boot_cpu_addr)
397 __cpu_logical_map[CPU_INIT_NO] = cpu;
398 if (!cpu_stopped(CPU_INIT_NO))
400 smp_get_save_area(c_cpus, cpu);
406 if (info->has_cpu_type) {
407 for (cpu = 0; cpu < info->combined; cpu++) {
408 if (info->cpu[cpu].address == boot_cpu_addr) {
409 smp_cpu_type = info->cpu[cpu].type;
415 for (cpu = 0; cpu < info->combined; cpu++) {
416 if (info->has_cpu_type && info->cpu[cpu].type != smp_cpu_type)
418 cpu_addr = info->cpu[cpu].address;
419 if (cpu_addr == boot_cpu_addr)
421 __cpu_logical_map[CPU_INIT_NO] = cpu_addr;
422 if (!cpu_stopped(CPU_INIT_NO)) {
426 smp_get_save_area(c_cpus, cpu_addr);
431 pr_info("%d configured CPUs, %d standby CPUs\n", c_cpus, s_cpus);
438 * Activate a secondary processor.
440 int __cpuinit start_secondary(void *cpuvoid)
445 /* Enable TOD clock interrupts on the secondary cpu. */
447 /* Enable cpu timer interrupts on the secondary cpu. */
449 /* Enable pfault pseudo page faults on this cpu. */
452 /* call cpu notifiers */
453 notify_cpu_starting(smp_processor_id());
454 /* Mark this cpu as online */
456 cpu_set(smp_processor_id(), cpu_online_map);
458 /* Switch on interrupts */
460 /* Print info about this processor */
461 print_cpu_info(&S390_lowcore.cpu_data);
462 /* cpu_idle will call schedule for us */
467 static void __init smp_create_idle(unsigned int cpu)
469 struct task_struct *p;
472 * don't care about the psw and regs settings since we'll never
473 * reschedule the forked task.
477 panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
478 current_set[cpu] = p;
481 static int __cpuinit smp_alloc_lowcore(int cpu)
483 unsigned long async_stack, panic_stack;
484 struct _lowcore *lowcore;
487 lc_order = sizeof(long) == 8 ? 1 : 0;
488 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
491 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
492 panic_stack = __get_free_page(GFP_KERNEL);
493 if (!panic_stack || !async_stack)
495 memcpy(lowcore, &S390_lowcore, 512);
496 memset((char *)lowcore + 512, 0, sizeof(*lowcore) - 512);
497 lowcore->async_stack = async_stack + ASYNC_SIZE;
498 lowcore->panic_stack = panic_stack + PAGE_SIZE;
501 if (MACHINE_HAS_IEEE) {
502 unsigned long save_area;
504 save_area = get_zeroed_page(GFP_KERNEL);
507 lowcore->extended_save_area_addr = (u32) save_area;
510 lowcore_ptr[cpu] = lowcore;
514 free_page(panic_stack);
515 free_pages(async_stack, ASYNC_ORDER);
516 free_pages((unsigned long) lowcore, lc_order);
520 #ifdef CONFIG_HOTPLUG_CPU
521 static void smp_free_lowcore(int cpu)
523 struct _lowcore *lowcore;
526 lc_order = sizeof(long) == 8 ? 1 : 0;
527 lowcore = lowcore_ptr[cpu];
529 if (MACHINE_HAS_IEEE)
530 free_page((unsigned long) lowcore->extended_save_area_addr);
532 free_page(lowcore->panic_stack - PAGE_SIZE);
533 free_pages(lowcore->async_stack - ASYNC_SIZE, ASYNC_ORDER);
534 free_pages((unsigned long) lowcore, lc_order);
535 lowcore_ptr[cpu] = NULL;
537 #endif /* CONFIG_HOTPLUG_CPU */
539 /* Upping and downing of CPUs */
540 int __cpuinit __cpu_up(unsigned int cpu)
542 struct task_struct *idle;
543 struct _lowcore *cpu_lowcore;
544 struct stack_frame *sf;
547 if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
549 if (smp_alloc_lowcore(cpu))
552 ccode = signal_processor_p((__u32)(unsigned long)(lowcore_ptr[cpu]),
553 cpu, sigp_set_prefix);
557 idle = current_set[cpu];
558 cpu_lowcore = lowcore_ptr[cpu];
559 cpu_lowcore->kernel_stack = (unsigned long)
560 task_stack_page(idle) + THREAD_SIZE;
561 cpu_lowcore->thread_info = (unsigned long) task_thread_info(idle);
562 sf = (struct stack_frame *) (cpu_lowcore->kernel_stack
563 - sizeof(struct pt_regs)
564 - sizeof(struct stack_frame));
565 memset(sf, 0, sizeof(struct stack_frame));
566 sf->gprs[9] = (unsigned long) sf;
567 cpu_lowcore->save_area[15] = (unsigned long) sf;
568 __ctl_store(cpu_lowcore->cregs_save_area, 0, 15);
571 : : "a" (&cpu_lowcore->access_regs_save_area) : "memory");
572 cpu_lowcore->percpu_offset = __per_cpu_offset[cpu];
573 cpu_lowcore->current_task = (unsigned long) idle;
574 cpu_lowcore->cpu_data.cpu_nr = cpu;
575 cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
576 cpu_lowcore->ipl_device = S390_lowcore.ipl_device;
579 while (signal_processor(cpu, sigp_restart) == sigp_busy)
582 while (!cpu_online(cpu))
587 static int __init setup_possible_cpus(char *s)
591 pcpus = simple_strtoul(s, NULL, 0);
592 cpu_possible_map = cpumask_of_cpu(0);
593 for (cpu = 1; cpu < pcpus && cpu < NR_CPUS; cpu++)
594 cpu_set(cpu, cpu_possible_map);
597 early_param("possible_cpus", setup_possible_cpus);
599 #ifdef CONFIG_HOTPLUG_CPU
601 int __cpu_disable(void)
603 struct ec_creg_mask_parms cr_parms;
604 int cpu = smp_processor_id();
606 cpu_clear(cpu, cpu_online_map);
608 /* Disable pfault pseudo page faults on this cpu. */
611 memset(&cr_parms.orvals, 0, sizeof(cr_parms.orvals));
612 memset(&cr_parms.andvals, 0xff, sizeof(cr_parms.andvals));
614 /* disable all external interrupts */
615 cr_parms.orvals[0] = 0;
616 cr_parms.andvals[0] = ~(1 << 15 | 1 << 14 | 1 << 13 | 1 << 12 |
617 1 << 11 | 1 << 10 | 1 << 6 | 1 << 4);
618 /* disable all I/O interrupts */
619 cr_parms.orvals[6] = 0;
620 cr_parms.andvals[6] = ~(1 << 31 | 1 << 30 | 1 << 29 | 1 << 28 |
621 1 << 27 | 1 << 26 | 1 << 25 | 1 << 24);
622 /* disable most machine checks */
623 cr_parms.orvals[14] = 0;
624 cr_parms.andvals[14] = ~(1 << 28 | 1 << 27 | 1 << 26 |
627 smp_ctl_bit_callback(&cr_parms);
632 void __cpu_die(unsigned int cpu)
634 /* Wait until target cpu is down */
635 while (!smp_cpu_not_running(cpu))
637 smp_free_lowcore(cpu);
638 pr_info("Processor %d stopped\n", cpu);
644 signal_processor(smp_processor_id(), sigp_stop);
649 #endif /* CONFIG_HOTPLUG_CPU */
651 void __init smp_prepare_cpus(unsigned int max_cpus)
654 unsigned long save_area = 0;
656 unsigned long async_stack, panic_stack;
657 struct _lowcore *lowcore;
663 /* request the 0x1201 emergency signal external interrupt */
664 if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
665 panic("Couldn't request external interrupt 0x1201");
666 print_cpu_info(&S390_lowcore.cpu_data);
668 /* Reallocate current lowcore, but keep its contents. */
669 lc_order = sizeof(long) == 8 ? 1 : 0;
670 lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, lc_order);
671 panic_stack = __get_free_page(GFP_KERNEL);
672 async_stack = __get_free_pages(GFP_KERNEL, ASYNC_ORDER);
674 if (MACHINE_HAS_IEEE)
675 save_area = get_zeroed_page(GFP_KERNEL);
678 local_mcck_disable();
679 lowcore_ptr[smp_processor_id()] = lowcore;
680 *lowcore = S390_lowcore;
681 lowcore->panic_stack = panic_stack + PAGE_SIZE;
682 lowcore->async_stack = async_stack + ASYNC_SIZE;
684 if (MACHINE_HAS_IEEE)
685 lowcore->extended_save_area_addr = (u32) save_area;
687 set_prefix((u32)(unsigned long) lowcore);
690 for_each_possible_cpu(cpu)
691 if (cpu != smp_processor_id())
692 smp_create_idle(cpu);
695 void __init smp_prepare_boot_cpu(void)
697 BUG_ON(smp_processor_id() != 0);
699 current_thread_info()->cpu = 0;
700 cpu_set(0, cpu_present_map);
701 cpu_set(0, cpu_online_map);
702 S390_lowcore.percpu_offset = __per_cpu_offset[0];
703 current_set[0] = current;
704 smp_cpu_state[0] = CPU_STATE_CONFIGURED;
705 smp_cpu_polarization[0] = POLARIZATION_UNKNWN;
708 void __init smp_cpus_done(unsigned int max_cpus)
713 * the frequency of the profiling timer can be changed
714 * by writing a multiplier value into /proc/profile.
716 * usually you want to run this on all CPUs ;)
718 int setup_profiling_timer(unsigned int multiplier)
723 #ifdef CONFIG_HOTPLUG_CPU
724 static ssize_t cpu_configure_show(struct sys_device *dev,
725 struct sysdev_attribute *attr, char *buf)
729 mutex_lock(&smp_cpu_state_mutex);
730 count = sprintf(buf, "%d\n", smp_cpu_state[dev->id]);
731 mutex_unlock(&smp_cpu_state_mutex);
735 static ssize_t cpu_configure_store(struct sys_device *dev,
736 struct sysdev_attribute *attr,
737 const char *buf, size_t count)
743 if (sscanf(buf, "%d %c", &val, &delim) != 1)
745 if (val != 0 && val != 1)
749 mutex_lock(&smp_cpu_state_mutex);
756 if (smp_cpu_state[cpu] == CPU_STATE_CONFIGURED) {
757 rc = sclp_cpu_deconfigure(__cpu_logical_map[cpu]);
759 smp_cpu_state[cpu] = CPU_STATE_STANDBY;
760 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
765 if (smp_cpu_state[cpu] == CPU_STATE_STANDBY) {
766 rc = sclp_cpu_configure(__cpu_logical_map[cpu]);
768 smp_cpu_state[cpu] = CPU_STATE_CONFIGURED;
769 smp_cpu_polarization[cpu] = POLARIZATION_UNKNWN;
777 mutex_unlock(&smp_cpu_state_mutex);
779 return rc ? rc : count;
781 static SYSDEV_ATTR(configure, 0644, cpu_configure_show, cpu_configure_store);
782 #endif /* CONFIG_HOTPLUG_CPU */
784 static ssize_t cpu_polarization_show(struct sys_device *dev,
785 struct sysdev_attribute *attr, char *buf)
790 mutex_lock(&smp_cpu_state_mutex);
791 switch (smp_cpu_polarization[cpu]) {
792 case POLARIZATION_HRZ:
793 count = sprintf(buf, "horizontal\n");
795 case POLARIZATION_VL:
796 count = sprintf(buf, "vertical:low\n");
798 case POLARIZATION_VM:
799 count = sprintf(buf, "vertical:medium\n");
801 case POLARIZATION_VH:
802 count = sprintf(buf, "vertical:high\n");
805 count = sprintf(buf, "unknown\n");
808 mutex_unlock(&smp_cpu_state_mutex);
811 static SYSDEV_ATTR(polarization, 0444, cpu_polarization_show, NULL);
813 static ssize_t show_cpu_address(struct sys_device *dev,
814 struct sysdev_attribute *attr, char *buf)
816 return sprintf(buf, "%d\n", __cpu_logical_map[dev->id]);
818 static SYSDEV_ATTR(address, 0444, show_cpu_address, NULL);
821 static struct attribute *cpu_common_attrs[] = {
822 #ifdef CONFIG_HOTPLUG_CPU
823 &attr_configure.attr,
826 &attr_polarization.attr,
830 static struct attribute_group cpu_common_attr_group = {
831 .attrs = cpu_common_attrs,
834 static ssize_t show_capability(struct sys_device *dev,
835 struct sysdev_attribute *attr, char *buf)
837 unsigned int capability;
840 rc = get_cpu_capability(&capability);
843 return sprintf(buf, "%u\n", capability);
845 static SYSDEV_ATTR(capability, 0444, show_capability, NULL);
847 static ssize_t show_idle_count(struct sys_device *dev,
848 struct sysdev_attribute *attr, char *buf)
850 struct s390_idle_data *idle;
851 unsigned long long idle_count;
853 idle = &per_cpu(s390_idle, dev->id);
854 spin_lock_irq(&idle->lock);
855 idle_count = idle->idle_count;
856 spin_unlock_irq(&idle->lock);
857 return sprintf(buf, "%llu\n", idle_count);
859 static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL);
861 static ssize_t show_idle_time(struct sys_device *dev,
862 struct sysdev_attribute *attr, char *buf)
864 struct s390_idle_data *idle;
865 unsigned long long new_time;
867 idle = &per_cpu(s390_idle, dev->id);
868 spin_lock_irq(&idle->lock);
870 new_time = get_clock();
871 idle->idle_time += new_time - idle->idle_enter;
872 idle->idle_enter = new_time;
874 new_time = idle->idle_time;
875 spin_unlock_irq(&idle->lock);
876 return sprintf(buf, "%llu\n", new_time >> 12);
878 static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL);
880 static struct attribute *cpu_online_attrs[] = {
881 &attr_capability.attr,
882 &attr_idle_count.attr,
883 &attr_idle_time_us.attr,
887 static struct attribute_group cpu_online_attr_group = {
888 .attrs = cpu_online_attrs,
891 static int __cpuinit smp_cpu_notify(struct notifier_block *self,
892 unsigned long action, void *hcpu)
894 unsigned int cpu = (unsigned int)(long)hcpu;
895 struct cpu *c = &per_cpu(cpu_devices, cpu);
896 struct sys_device *s = &c->sysdev;
897 struct s390_idle_data *idle;
901 case CPU_ONLINE_FROZEN:
902 idle = &per_cpu(s390_idle, cpu);
903 spin_lock_irq(&idle->lock);
904 idle->idle_enter = 0;
906 idle->idle_count = 0;
907 spin_unlock_irq(&idle->lock);
908 if (sysfs_create_group(&s->kobj, &cpu_online_attr_group))
912 case CPU_DEAD_FROZEN:
913 sysfs_remove_group(&s->kobj, &cpu_online_attr_group);
919 static struct notifier_block __cpuinitdata smp_cpu_nb = {
920 .notifier_call = smp_cpu_notify,
923 static int __devinit smp_add_present_cpu(int cpu)
925 struct cpu *c = &per_cpu(cpu_devices, cpu);
926 struct sys_device *s = &c->sysdev;
930 rc = register_cpu(c, cpu);
933 rc = sysfs_create_group(&s->kobj, &cpu_common_attr_group);
936 if (!cpu_online(cpu))
938 rc = sysfs_create_group(&s->kobj, &cpu_online_attr_group);
941 sysfs_remove_group(&s->kobj, &cpu_common_attr_group);
943 #ifdef CONFIG_HOTPLUG_CPU
950 #ifdef CONFIG_HOTPLUG_CPU
952 int __ref smp_rescan_cpus(void)
959 mutex_lock(&smp_cpu_state_mutex);
960 newcpus = cpu_present_map;
961 rc = __smp_rescan_cpus();
964 cpus_andnot(newcpus, cpu_present_map, newcpus);
965 for_each_cpu_mask(cpu, newcpus) {
966 rc = smp_add_present_cpu(cpu);
968 cpu_clear(cpu, cpu_present_map);
972 mutex_unlock(&smp_cpu_state_mutex);
974 if (!cpus_empty(newcpus))
975 topology_schedule_update();
979 static ssize_t __ref rescan_store(struct sysdev_class *class, const char *buf,
984 rc = smp_rescan_cpus();
985 return rc ? rc : count;
987 static SYSDEV_CLASS_ATTR(rescan, 0200, NULL, rescan_store);
988 #endif /* CONFIG_HOTPLUG_CPU */
990 static ssize_t dispatching_show(struct sysdev_class *class, char *buf)
994 mutex_lock(&smp_cpu_state_mutex);
995 count = sprintf(buf, "%d\n", cpu_management);
996 mutex_unlock(&smp_cpu_state_mutex);
1000 static ssize_t dispatching_store(struct sysdev_class *dev, const char *buf,
1006 if (sscanf(buf, "%d %c", &val, &delim) != 1)
1008 if (val != 0 && val != 1)
1012 mutex_lock(&smp_cpu_state_mutex);
1013 if (cpu_management == val)
1015 rc = topology_set_cpu_management(val);
1017 cpu_management = val;
1019 mutex_unlock(&smp_cpu_state_mutex);
1021 return rc ? rc : count;
1023 static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show,
1026 static int __init topology_init(void)
1031 register_cpu_notifier(&smp_cpu_nb);
1033 #ifdef CONFIG_HOTPLUG_CPU
1034 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_rescan);
1038 rc = sysdev_class_create_file(&cpu_sysdev_class, &attr_dispatching);
1041 for_each_present_cpu(cpu) {
1042 rc = smp_add_present_cpu(cpu);
1048 subsys_initcall(topology_init);