1 /* smp.c: Sparc64 SMP support.
3 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
6 #include <linux/module.h>
7 #include <linux/kernel.h>
8 #include <linux/sched.h>
10 #include <linux/pagemap.h>
11 #include <linux/threads.h>
12 #include <linux/smp.h>
13 #include <linux/smp_lock.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel_stat.h>
16 #include <linux/delay.h>
17 #include <linux/init.h>
18 #include <linux/spinlock.h>
20 #include <linux/seq_file.h>
21 #include <linux/cache.h>
22 #include <linux/jiffies.h>
23 #include <linux/profile.h>
24 #include <linux/bootmem.h>
27 #include <asm/ptrace.h>
28 #include <asm/atomic.h>
29 #include <asm/tlbflush.h>
30 #include <asm/mmu_context.h>
31 #include <asm/cpudata.h>
35 #include <asm/pgtable.h>
36 #include <asm/oplib.h>
37 #include <asm/uaccess.h>
38 #include <asm/timer.h>
39 #include <asm/starfire.h>
41 #include <asm/sections.h>
43 extern void calibrate_delay(void);
45 /* Please don't make this stuff initdata!!! --DaveM */
46 static unsigned char boot_cpu_id;
48 cpumask_t cpu_online_map __read_mostly = CPU_MASK_NONE;
49 cpumask_t phys_cpu_present_map __read_mostly = CPU_MASK_NONE;
50 static cpumask_t smp_commenced_mask;
51 static cpumask_t cpu_callout_map;
53 void smp_info(struct seq_file *m)
57 seq_printf(m, "State:\n");
58 for (i = 0; i < NR_CPUS; i++) {
61 "CPU%d:\t\tonline\n", i);
65 void smp_bogo(struct seq_file *m)
69 for (i = 0; i < NR_CPUS; i++)
72 "Cpu%dBogo\t: %lu.%02lu\n"
73 "Cpu%dClkTck\t: %016lx\n",
74 i, cpu_data(i).udelay_val / (500000/HZ),
75 (cpu_data(i).udelay_val / (5000/HZ)) % 100,
76 i, cpu_data(i).clock_tick);
79 void __init smp_store_cpu_info(int id)
83 /* multiplier and counter set by
84 smp_setup_percpu_timer() */
85 cpu_data(id).udelay_val = loops_per_jiffy;
87 cpu_find_by_mid(id, &cpu_node);
88 cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
89 "clock-frequency", 0);
91 cpu_data(id).idle_volume = 1;
93 cpu_data(id).dcache_size = prom_getintdefault(cpu_node, "dcache-size",
95 cpu_data(id).dcache_line_size =
96 prom_getintdefault(cpu_node, "dcache-line-size", 32);
97 cpu_data(id).icache_size = prom_getintdefault(cpu_node, "icache-size",
99 cpu_data(id).icache_line_size =
100 prom_getintdefault(cpu_node, "icache-line-size", 32);
101 cpu_data(id).ecache_size = prom_getintdefault(cpu_node, "ecache-size",
103 cpu_data(id).ecache_line_size =
104 prom_getintdefault(cpu_node, "ecache-line-size", 64);
105 printk("CPU[%d]: Caches "
106 "D[sz(%d):line_sz(%d)] "
107 "I[sz(%d):line_sz(%d)] "
108 "E[sz(%d):line_sz(%d)]\n",
110 cpu_data(id).dcache_size, cpu_data(id).dcache_line_size,
111 cpu_data(id).icache_size, cpu_data(id).icache_line_size,
112 cpu_data(id).ecache_size, cpu_data(id).ecache_line_size);
115 static void smp_setup_percpu_timer(void);
117 static volatile unsigned long callin_flag = 0;
119 void __init smp_callin(void)
121 int cpuid = hard_smp_processor_id();
123 __local_per_cpu_offset = __per_cpu_offset(cpuid);
125 if (tlb_type == hypervisor) {
126 sun4v_register_fault_status();
127 sun4v_ktsb_register();
132 smp_setup_percpu_timer();
134 if (cheetah_pcache_forced_on)
135 cheetah_enable_pcache();
140 smp_store_cpu_info(cpuid);
142 __asm__ __volatile__("membar #Sync\n\t"
143 "flush %%g6" : : : "memory");
145 /* Clear this or we will die instantly when we
146 * schedule back to this idler...
148 current_thread_info()->new_child = 0;
150 /* Attach to the address space of init_task. */
151 atomic_inc(&init_mm.mm_count);
152 current->active_mm = &init_mm;
154 while (!cpu_isset(cpuid, smp_commenced_mask))
157 cpu_set(cpuid, cpu_online_map);
159 /* idle thread is expected to have preempt disabled */
165 printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
166 panic("SMP bolixed\n");
169 static unsigned long current_tick_offset __read_mostly;
171 /* This tick register synchronization scheme is taken entirely from
172 * the ia64 port, see arch/ia64/kernel/smpboot.c for details and credit.
174 * The only change I've made is to rework it so that the master
175 * initiates the synchonization instead of the slave. -DaveM
179 #define SLAVE (SMP_CACHE_BYTES/sizeof(unsigned long))
181 #define NUM_ROUNDS 64 /* magic value */
182 #define NUM_ITERS 5 /* likewise */
184 static DEFINE_SPINLOCK(itc_sync_lock);
185 static unsigned long go[SLAVE + 1];
187 #define DEBUG_TICK_SYNC 0
189 static inline long get_delta (long *rt, long *master)
191 unsigned long best_t0 = 0, best_t1 = ~0UL, best_tm = 0;
192 unsigned long tcenter, t0, t1, tm;
195 for (i = 0; i < NUM_ITERS; i++) {
196 t0 = tick_ops->get_tick();
199 while (!(tm = go[SLAVE]))
203 t1 = tick_ops->get_tick();
205 if (t1 - t0 < best_t1 - best_t0)
206 best_t0 = t0, best_t1 = t1, best_tm = tm;
209 *rt = best_t1 - best_t0;
210 *master = best_tm - best_t0;
212 /* average best_t0 and best_t1 without overflow: */
213 tcenter = (best_t0/2 + best_t1/2);
214 if (best_t0 % 2 + best_t1 % 2 == 2)
216 return tcenter - best_tm;
219 void smp_synchronize_tick_client(void)
221 long i, delta, adj, adjust_latency = 0, done = 0;
222 unsigned long flags, rt, master_time_stamp, bound;
225 long rt; /* roundtrip time */
226 long master; /* master's timestamp */
227 long diff; /* difference between midpoint and master's timestamp */
228 long lat; /* estimate of itc adjustment latency */
237 local_irq_save(flags);
239 for (i = 0; i < NUM_ROUNDS; i++) {
240 delta = get_delta(&rt, &master_time_stamp);
242 done = 1; /* let's lock on to this... */
248 adjust_latency += -delta;
249 adj = -delta + adjust_latency/4;
253 tick_ops->add_tick(adj, current_tick_offset);
257 t[i].master = master_time_stamp;
259 t[i].lat = adjust_latency/4;
263 local_irq_restore(flags);
266 for (i = 0; i < NUM_ROUNDS; i++)
267 printk("rt=%5ld master=%5ld diff=%5ld adjlat=%5ld\n",
268 t[i].rt, t[i].master, t[i].diff, t[i].lat);
271 printk(KERN_INFO "CPU %d: synchronized TICK with master CPU (last diff %ld cycles,"
272 "maxerr %lu cycles)\n", smp_processor_id(), delta, rt);
275 static void smp_start_sync_tick_client(int cpu);
277 static void smp_synchronize_one_tick(int cpu)
279 unsigned long flags, i;
283 smp_start_sync_tick_client(cpu);
285 /* wait for client to be ready */
289 /* now let the client proceed into his loop */
293 spin_lock_irqsave(&itc_sync_lock, flags);
295 for (i = 0; i < NUM_ROUNDS*NUM_ITERS; i++) {
300 go[SLAVE] = tick_ops->get_tick();
304 spin_unlock_irqrestore(&itc_sync_lock, flags);
307 extern unsigned long sparc64_cpu_startup;
309 /* The OBP cpu startup callback truncates the 3rd arg cookie to
310 * 32-bits (I think) so to be safe we have it read the pointer
311 * contained here so we work on >4GB machines. -DaveM
313 static struct thread_info *cpu_new_thread = NULL;
315 static int __devinit smp_boot_one_cpu(unsigned int cpu)
317 unsigned long entry =
318 (unsigned long)(&sparc64_cpu_startup);
319 unsigned long cookie =
320 (unsigned long)(&cpu_new_thread);
321 struct task_struct *p;
322 int timeout, ret, cpu_node;
326 cpu_new_thread = task_thread_info(p);
327 cpu_set(cpu, cpu_callout_map);
329 cpu_find_by_mid(cpu, &cpu_node);
330 prom_startcpu(cpu_node, entry, cookie);
332 for (timeout = 0; timeout < 5000000; timeout++) {
340 printk("Processor %d is stuck.\n", cpu);
341 cpu_clear(cpu, cpu_callout_map);
344 cpu_new_thread = NULL;
349 static void spitfire_xcall_helper(u64 data0, u64 data1, u64 data2, u64 pstate, unsigned long cpu)
354 if (this_is_starfire) {
355 /* map to real upaid */
356 cpu = (((cpu & 0x3c) << 1) |
357 ((cpu & 0x40) >> 4) |
361 target = (cpu << 14) | 0x70;
363 /* Ok, this is the real Spitfire Errata #54.
364 * One must read back from a UDB internal register
365 * after writes to the UDB interrupt dispatch, but
366 * before the membar Sync for that write.
367 * So we use the high UDB control register (ASI 0x7f,
368 * ADDR 0x20) for the dummy read. -DaveM
371 __asm__ __volatile__(
372 "wrpr %1, %2, %%pstate\n\t"
373 "stxa %4, [%0] %3\n\t"
374 "stxa %5, [%0+%8] %3\n\t"
376 "stxa %6, [%0+%8] %3\n\t"
378 "stxa %%g0, [%7] %3\n\t"
381 "ldxa [%%g1] 0x7f, %%g0\n\t"
384 : "r" (pstate), "i" (PSTATE_IE), "i" (ASI_INTR_W),
385 "r" (data0), "r" (data1), "r" (data2), "r" (target),
386 "r" (0x10), "0" (tmp)
389 /* NOTE: PSTATE_IE is still clear. */
392 __asm__ __volatile__("ldxa [%%g0] %1, %0"
394 : "i" (ASI_INTR_DISPATCH_STAT));
396 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
403 } while (result & 0x1);
404 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
407 printk("CPU[%d]: mondo stuckage result[%016lx]\n",
408 smp_processor_id(), result);
415 static __inline__ void spitfire_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
420 __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
421 for_each_cpu_mask(i, mask)
422 spitfire_xcall_helper(data0, data1, data2, pstate, i);
425 /* Cheetah now allows to send the whole 64-bytes of data in the interrupt
426 * packet, but we have no use for that. However we do take advantage of
427 * the new pipelining feature (ie. dispatch to multiple cpus simultaneously).
429 static void cheetah_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
432 int nack_busy_id, is_jbus;
434 if (cpus_empty(mask))
437 /* Unfortunately, someone at Sun had the brilliant idea to make the
438 * busy/nack fields hard-coded by ITID number for this Ultra-III
439 * derivative processor.
441 __asm__ ("rdpr %%ver, %0" : "=r" (ver));
442 is_jbus = ((ver >> 32) == __JALAPENO_ID ||
443 (ver >> 32) == __SERRANO_ID);
445 __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
448 __asm__ __volatile__("wrpr %0, %1, %%pstate\n\t"
449 : : "r" (pstate), "i" (PSTATE_IE));
451 /* Setup the dispatch data registers. */
452 __asm__ __volatile__("stxa %0, [%3] %6\n\t"
453 "stxa %1, [%4] %6\n\t"
454 "stxa %2, [%5] %6\n\t"
457 : "r" (data0), "r" (data1), "r" (data2),
458 "r" (0x40), "r" (0x50), "r" (0x60),
465 for_each_cpu_mask(i, mask) {
466 u64 target = (i << 14) | 0x70;
469 target |= (nack_busy_id << 24);
470 __asm__ __volatile__(
471 "stxa %%g0, [%0] %1\n\t"
474 : "r" (target), "i" (ASI_INTR_W));
479 /* Now, poll for completion. */
484 stuck = 100000 * nack_busy_id;
486 __asm__ __volatile__("ldxa [%%g0] %1, %0"
487 : "=r" (dispatch_stat)
488 : "i" (ASI_INTR_DISPATCH_STAT));
489 if (dispatch_stat == 0UL) {
490 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
496 } while (dispatch_stat & 0x5555555555555555UL);
498 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
501 if ((dispatch_stat & ~(0x5555555555555555UL)) == 0) {
502 /* Busy bits will not clear, continue instead
503 * of freezing up on this cpu.
505 printk("CPU[%d]: mondo stuckage result[%016lx]\n",
506 smp_processor_id(), dispatch_stat);
508 int i, this_busy_nack = 0;
510 /* Delay some random time with interrupts enabled
511 * to prevent deadlock.
513 udelay(2 * nack_busy_id);
515 /* Clear out the mask bits for cpus which did not
518 for_each_cpu_mask(i, mask) {
522 check_mask = (0x2UL << (2*i));
524 check_mask = (0x2UL <<
526 if ((dispatch_stat & check_mask) == 0)
537 /* Multi-cpu list version. */
538 static int init_cpu_list(u16 *list, cpumask_t mask)
543 for_each_cpu_mask(i, mask)
549 static int update_cpu_list(u16 *list, int orig_cnt, cpumask_t mask)
553 for (i = 0; i < orig_cnt; i++) {
554 if (list[i] == 0xffff)
558 return init_cpu_list(list, mask);
561 static void hypervisor_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
563 int this_cpu = get_cpu();
564 struct trap_per_cpu *tb = &trap_block[this_cpu];
565 u64 *mondo = __va(tb->cpu_mondo_block_pa);
566 u16 *cpu_list = __va(tb->cpu_list_pa);
575 cnt = init_cpu_list(cpu_list, mask);
577 register unsigned long func __asm__("%o5");
578 register unsigned long arg0 __asm__("%o0");
579 register unsigned long arg1 __asm__("%o1");
580 register unsigned long arg2 __asm__("%o2");
582 func = HV_FAST_CPU_MONDO_SEND;
584 arg1 = tb->cpu_list_pa;
585 arg2 = tb->cpu_mondo_block_pa;
587 __asm__ __volatile__("ta %8"
588 : "=&r" (func), "=&r" (arg0),
589 "=&r" (arg1), "=&r" (arg2)
590 : "0" (func), "1" (arg0),
591 "2" (arg1), "3" (arg2),
594 if (likely(arg0 == HV_EOK))
597 if (unlikely(++retries > 100)) {
598 printk("CPU[%d]: sun4v mondo error %lu\n",
603 cnt = update_cpu_list(cpu_list, cnt, mask);
611 /* Single-cpu list version. */
612 static void hypervisor_xcall_deliver(u64 data0, u64 data1, u64 data2, cpumask_t mask)
614 int this_cpu = get_cpu();
615 struct trap_per_cpu *tb = &trap_block[this_cpu];
616 u64 *mondo = __va(tb->cpu_mondo_block_pa);
617 u16 *cpu_list = __va(tb->cpu_list_pa);
625 for_each_cpu_mask(i, mask) {
629 register unsigned long func __asm__("%o5");
630 register unsigned long arg0 __asm__("%o0");
631 register unsigned long arg1 __asm__("%o1");
632 register unsigned long arg2 __asm__("%o2");
635 func = HV_FAST_CPU_MONDO_SEND;
637 arg1 = tb->cpu_list_pa;
638 arg2 = tb->cpu_mondo_block_pa;
640 __asm__ __volatile__("ta %8"
641 : "=&r" (func), "=&r" (arg0),
642 "=&r" (arg1), "=&r" (arg2)
643 : "0" (func), "1" (arg0),
644 "2" (arg1), "3" (arg2),
647 if (likely(arg0 == HV_EOK))
650 if (unlikely(++retries > 100)) {
651 printk("CPU[%d]: sun4v mondo error %lu\n",
664 /* Send cross call to all processors mentioned in MASK
667 static void smp_cross_call_masked(unsigned long *func, u32 ctx, u64 data1, u64 data2, cpumask_t mask)
669 u64 data0 = (((u64)ctx)<<32 | (((u64)func) & 0xffffffff));
670 int this_cpu = get_cpu();
672 cpus_and(mask, mask, cpu_online_map);
673 cpu_clear(this_cpu, mask);
675 if (tlb_type == spitfire)
676 spitfire_xcall_deliver(data0, data1, data2, mask);
677 else if (tlb_type == cheetah || tlb_type == cheetah_plus)
678 cheetah_xcall_deliver(data0, data1, data2, mask);
680 hypervisor_xcall_deliver(data0, data1, data2, mask);
681 /* NOTE: Caller runs local copy on master. */
686 extern unsigned long xcall_sync_tick;
688 static void smp_start_sync_tick_client(int cpu)
690 cpumask_t mask = cpumask_of_cpu(cpu);
692 smp_cross_call_masked(&xcall_sync_tick,
696 /* Send cross call to all processors except self. */
697 #define smp_cross_call(func, ctx, data1, data2) \
698 smp_cross_call_masked(func, ctx, data1, data2, cpu_online_map)
700 struct call_data_struct {
701 void (*func) (void *info);
707 static DEFINE_SPINLOCK(call_lock);
708 static struct call_data_struct *call_data;
710 extern unsigned long xcall_call_function;
713 * You must not call this function with disabled interrupts or from a
714 * hardware interrupt handler or from a bottom half handler.
716 static int smp_call_function_mask(void (*func)(void *info), void *info,
717 int nonatomic, int wait, cpumask_t mask)
719 struct call_data_struct data;
720 int cpus = cpus_weight(mask) - 1;
726 /* Can deadlock when called with interrupts disabled */
727 WARN_ON(irqs_disabled());
731 atomic_set(&data.finished, 0);
734 spin_lock(&call_lock);
738 smp_cross_call_masked(&xcall_call_function, 0, 0, 0, mask);
741 * Wait for other cpus to complete function or at
742 * least snap the call data.
745 while (atomic_read(&data.finished) != cpus) {
752 spin_unlock(&call_lock);
757 spin_unlock(&call_lock);
758 printk("XCALL: Remote cpus not responding, ncpus=%ld finished=%ld\n",
759 (long) num_online_cpus() - 1L,
760 (long) atomic_read(&data.finished));
764 int smp_call_function(void (*func)(void *info), void *info,
765 int nonatomic, int wait)
767 return smp_call_function_mask(func, info, nonatomic, wait,
771 void smp_call_function_client(int irq, struct pt_regs *regs)
773 void (*func) (void *info) = call_data->func;
774 void *info = call_data->info;
776 clear_softint(1 << irq);
777 if (call_data->wait) {
778 /* let initiator proceed only after completion */
780 atomic_inc(&call_data->finished);
782 /* let initiator proceed after getting data */
783 atomic_inc(&call_data->finished);
788 static void tsb_sync(void *info)
790 struct mm_struct *mm = info;
792 if (current->active_mm == mm)
793 tsb_context_switch(mm);
796 void smp_tsb_sync(struct mm_struct *mm)
798 smp_call_function_mask(tsb_sync, mm, 0, 1, mm->cpu_vm_mask);
801 extern unsigned long xcall_flush_tlb_mm;
802 extern unsigned long xcall_flush_tlb_pending;
803 extern unsigned long xcall_flush_tlb_kernel_range;
804 extern unsigned long xcall_report_regs;
805 extern unsigned long xcall_receive_signal;
807 #ifdef DCACHE_ALIASING_POSSIBLE
808 extern unsigned long xcall_flush_dcache_page_cheetah;
810 extern unsigned long xcall_flush_dcache_page_spitfire;
812 #ifdef CONFIG_DEBUG_DCFLUSH
813 extern atomic_t dcpage_flushes;
814 extern atomic_t dcpage_flushes_xcall;
817 static __inline__ void __local_flush_dcache_page(struct page *page)
819 #ifdef DCACHE_ALIASING_POSSIBLE
820 __flush_dcache_page(page_address(page),
821 ((tlb_type == spitfire) &&
822 page_mapping(page) != NULL));
824 if (page_mapping(page) != NULL &&
825 tlb_type == spitfire)
826 __flush_icache_page(__pa(page_address(page)));
830 void smp_flush_dcache_page_impl(struct page *page, int cpu)
832 cpumask_t mask = cpumask_of_cpu(cpu);
835 if (tlb_type == hypervisor)
838 #ifdef CONFIG_DEBUG_DCFLUSH
839 atomic_inc(&dcpage_flushes);
842 this_cpu = get_cpu();
844 if (cpu == this_cpu) {
845 __local_flush_dcache_page(page);
846 } else if (cpu_online(cpu)) {
847 void *pg_addr = page_address(page);
850 if (tlb_type == spitfire) {
852 ((u64)&xcall_flush_dcache_page_spitfire);
853 if (page_mapping(page) != NULL)
854 data0 |= ((u64)1 << 32);
855 spitfire_xcall_deliver(data0,
859 } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
860 #ifdef DCACHE_ALIASING_POSSIBLE
862 ((u64)&xcall_flush_dcache_page_cheetah);
863 cheetah_xcall_deliver(data0,
868 #ifdef CONFIG_DEBUG_DCFLUSH
869 atomic_inc(&dcpage_flushes_xcall);
876 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
878 void *pg_addr = page_address(page);
879 cpumask_t mask = cpu_online_map;
883 if (tlb_type == hypervisor)
886 this_cpu = get_cpu();
888 cpu_clear(this_cpu, mask);
890 #ifdef CONFIG_DEBUG_DCFLUSH
891 atomic_inc(&dcpage_flushes);
893 if (cpus_empty(mask))
895 if (tlb_type == spitfire) {
896 data0 = ((u64)&xcall_flush_dcache_page_spitfire);
897 if (page_mapping(page) != NULL)
898 data0 |= ((u64)1 << 32);
899 spitfire_xcall_deliver(data0,
903 } else if (tlb_type == cheetah || tlb_type == cheetah_plus) {
904 #ifdef DCACHE_ALIASING_POSSIBLE
905 data0 = ((u64)&xcall_flush_dcache_page_cheetah);
906 cheetah_xcall_deliver(data0,
911 #ifdef CONFIG_DEBUG_DCFLUSH
912 atomic_inc(&dcpage_flushes_xcall);
915 __local_flush_dcache_page(page);
920 void smp_receive_signal(int cpu)
922 cpumask_t mask = cpumask_of_cpu(cpu);
924 if (cpu_online(cpu)) {
925 u64 data0 = (((u64)&xcall_receive_signal) & 0xffffffff);
927 if (tlb_type == spitfire)
928 spitfire_xcall_deliver(data0, 0, 0, mask);
929 else if (tlb_type == cheetah || tlb_type == cheetah_plus)
930 cheetah_xcall_deliver(data0, 0, 0, mask);
931 else if (tlb_type == hypervisor)
932 hypervisor_xcall_deliver(data0, 0, 0, mask);
936 void smp_receive_signal_client(int irq, struct pt_regs *regs)
938 /* Just return, rtrap takes care of the rest. */
939 clear_softint(1 << irq);
942 void smp_report_regs(void)
944 smp_cross_call(&xcall_report_regs, 0, 0, 0);
947 /* We know that the window frames of the user have been flushed
948 * to the stack before we get here because all callers of us
949 * are flush_tlb_*() routines, and these run after flush_cache_*()
950 * which performs the flushw.
952 * The SMP TLB coherency scheme we use works as follows:
954 * 1) mm->cpu_vm_mask is a bit mask of which cpus an address
955 * space has (potentially) executed on, this is the heuristic
956 * we use to avoid doing cross calls.
958 * Also, for flushing from kswapd and also for clones, we
959 * use cpu_vm_mask as the list of cpus to make run the TLB.
961 * 2) TLB context numbers are shared globally across all processors
962 * in the system, this allows us to play several games to avoid
965 * One invariant is that when a cpu switches to a process, and
966 * that processes tsk->active_mm->cpu_vm_mask does not have the
967 * current cpu's bit set, that tlb context is flushed locally.
969 * If the address space is non-shared (ie. mm->count == 1) we avoid
970 * cross calls when we want to flush the currently running process's
971 * tlb state. This is done by clearing all cpu bits except the current
972 * processor's in current->active_mm->cpu_vm_mask and performing the
973 * flush locally only. This will force any subsequent cpus which run
974 * this task to flush the context from the local tlb if the process
975 * migrates to another cpu (again).
977 * 3) For shared address spaces (threads) and swapping we bite the
978 * bullet for most cases and perform the cross call (but only to
979 * the cpus listed in cpu_vm_mask).
981 * The performance gain from "optimizing" away the cross call for threads is
982 * questionable (in theory the big win for threads is the massive sharing of
983 * address space state across processors).
986 /* This currently is only used by the hugetlb arch pre-fault
987 * hook on UltraSPARC-III+ and later when changing the pagesize
988 * bits of the context register for an address space.
990 void smp_flush_tlb_mm(struct mm_struct *mm)
992 u32 ctx = CTX_HWBITS(mm->context);
995 if (atomic_read(&mm->mm_users) == 1) {
996 mm->cpu_vm_mask = cpumask_of_cpu(cpu);
997 goto local_flush_and_out;
1000 smp_cross_call_masked(&xcall_flush_tlb_mm,
1004 local_flush_and_out:
1005 __flush_tlb_mm(ctx, SECONDARY_CONTEXT);
1010 void smp_flush_tlb_pending(struct mm_struct *mm, unsigned long nr, unsigned long *vaddrs)
1012 u32 ctx = CTX_HWBITS(mm->context);
1013 int cpu = get_cpu();
1015 if (mm == current->active_mm && atomic_read(&mm->mm_users) == 1)
1016 mm->cpu_vm_mask = cpumask_of_cpu(cpu);
1018 smp_cross_call_masked(&xcall_flush_tlb_pending,
1019 ctx, nr, (unsigned long) vaddrs,
1022 __flush_tlb_pending(ctx, nr, vaddrs);
1027 void smp_flush_tlb_kernel_range(unsigned long start, unsigned long end)
1030 end = PAGE_ALIGN(end);
1032 smp_cross_call(&xcall_flush_tlb_kernel_range,
1035 __flush_tlb_kernel_range(start, end);
1040 /* #define CAPTURE_DEBUG */
1041 extern unsigned long xcall_capture;
1043 static atomic_t smp_capture_depth = ATOMIC_INIT(0);
1044 static atomic_t smp_capture_registry = ATOMIC_INIT(0);
1045 static unsigned long penguins_are_doing_time;
1047 void smp_capture(void)
1049 int result = atomic_add_ret(1, &smp_capture_depth);
1052 int ncpus = num_online_cpus();
1054 #ifdef CAPTURE_DEBUG
1055 printk("CPU[%d]: Sending penguins to jail...",
1056 smp_processor_id());
1058 penguins_are_doing_time = 1;
1059 membar_storestore_loadstore();
1060 atomic_inc(&smp_capture_registry);
1061 smp_cross_call(&xcall_capture, 0, 0, 0);
1062 while (atomic_read(&smp_capture_registry) != ncpus)
1064 #ifdef CAPTURE_DEBUG
1070 void smp_release(void)
1072 if (atomic_dec_and_test(&smp_capture_depth)) {
1073 #ifdef CAPTURE_DEBUG
1074 printk("CPU[%d]: Giving pardon to "
1075 "imprisoned penguins\n",
1076 smp_processor_id());
1078 penguins_are_doing_time = 0;
1079 membar_storeload_storestore();
1080 atomic_dec(&smp_capture_registry);
1084 /* Imprisoned penguins run with %pil == 15, but PSTATE_IE set, so they
1085 * can service tlb flush xcalls...
1087 extern void prom_world(int);
1089 void smp_penguin_jailcell(int irq, struct pt_regs *regs)
1091 clear_softint(1 << irq);
1095 __asm__ __volatile__("flushw");
1097 atomic_inc(&smp_capture_registry);
1098 membar_storeload_storestore();
1099 while (penguins_are_doing_time)
1101 atomic_dec(&smp_capture_registry);
1107 #define prof_multiplier(__cpu) cpu_data(__cpu).multiplier
1108 #define prof_counter(__cpu) cpu_data(__cpu).counter
1110 void smp_percpu_timer_interrupt(struct pt_regs *regs)
1112 unsigned long compare, tick, pstate;
1113 int cpu = smp_processor_id();
1114 int user = user_mode(regs);
1117 * Check for level 14 softint.
1120 unsigned long tick_mask = tick_ops->softint_mask;
1122 if (!(get_softint() & tick_mask)) {
1123 extern void handler_irq(int, struct pt_regs *);
1125 handler_irq(14, regs);
1128 clear_softint(tick_mask);
1132 profile_tick(CPU_PROFILING, regs);
1133 if (!--prof_counter(cpu)) {
1136 if (cpu == boot_cpu_id) {
1137 kstat_this_cpu.irqs[0]++;
1138 timer_tick_interrupt(regs);
1141 update_process_times(user);
1145 prof_counter(cpu) = prof_multiplier(cpu);
1148 /* Guarantee that the following sequences execute
1151 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
1152 "wrpr %0, %1, %%pstate"
1156 compare = tick_ops->add_compare(current_tick_offset);
1157 tick = tick_ops->get_tick();
1159 /* Restore PSTATE_IE. */
1160 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
1163 } while (time_after_eq(tick, compare));
1166 static void __init smp_setup_percpu_timer(void)
1168 int cpu = smp_processor_id();
1169 unsigned long pstate;
1171 prof_counter(cpu) = prof_multiplier(cpu) = 1;
1173 /* Guarantee that the following sequences execute
1176 __asm__ __volatile__("rdpr %%pstate, %0\n\t"
1177 "wrpr %0, %1, %%pstate"
1181 tick_ops->init_tick(current_tick_offset);
1183 /* Restore PSTATE_IE. */
1184 __asm__ __volatile__("wrpr %0, 0x0, %%pstate"
1189 void __init smp_tick_init(void)
1191 boot_cpu_id = hard_smp_processor_id();
1192 current_tick_offset = timer_tick_offset;
1194 cpu_set(boot_cpu_id, cpu_online_map);
1195 prof_counter(boot_cpu_id) = prof_multiplier(boot_cpu_id) = 1;
1198 /* /proc/profile writes can call this, don't __init it please. */
1199 static DEFINE_SPINLOCK(prof_setup_lock);
1201 int setup_profiling_timer(unsigned int multiplier)
1203 unsigned long flags;
1206 if ((!multiplier) || (timer_tick_offset / multiplier) < 1000)
1209 spin_lock_irqsave(&prof_setup_lock, flags);
1210 for (i = 0; i < NR_CPUS; i++)
1211 prof_multiplier(i) = multiplier;
1212 current_tick_offset = (timer_tick_offset / multiplier);
1213 spin_unlock_irqrestore(&prof_setup_lock, flags);
1218 /* Constrain the number of cpus to max_cpus. */
1219 void __init smp_prepare_cpus(unsigned int max_cpus)
1221 if (num_possible_cpus() > max_cpus) {
1225 while (!cpu_find_by_instance(instance, NULL, &mid)) {
1226 if (mid != boot_cpu_id) {
1227 cpu_clear(mid, phys_cpu_present_map);
1228 if (num_possible_cpus() <= max_cpus)
1235 smp_store_cpu_info(boot_cpu_id);
1238 /* Set this up early so that things like the scheduler can init
1239 * properly. We use the same cpu mask for both the present and
1242 void __init smp_setup_cpu_possible_map(void)
1247 while (!cpu_find_by_instance(instance, NULL, &mid)) {
1249 cpu_set(mid, phys_cpu_present_map);
1254 void __devinit smp_prepare_boot_cpu(void)
1256 int cpu = hard_smp_processor_id();
1258 if (cpu >= NR_CPUS) {
1259 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
1263 current_thread_info()->cpu = cpu;
1264 __local_per_cpu_offset = __per_cpu_offset(cpu);
1266 cpu_set(smp_processor_id(), cpu_online_map);
1267 cpu_set(smp_processor_id(), phys_cpu_present_map);
1270 int __devinit __cpu_up(unsigned int cpu)
1272 int ret = smp_boot_one_cpu(cpu);
1275 cpu_set(cpu, smp_commenced_mask);
1276 while (!cpu_isset(cpu, cpu_online_map))
1278 if (!cpu_isset(cpu, cpu_online_map)) {
1281 /* On SUN4V, writes to %tick and %stick are
1284 if (tlb_type != hypervisor)
1285 smp_synchronize_one_tick(cpu);
1291 void __init smp_cpus_done(unsigned int max_cpus)
1293 unsigned long bogosum = 0;
1296 for (i = 0; i < NR_CPUS; i++) {
1298 bogosum += cpu_data(i).udelay_val;
1300 printk("Total of %ld processors activated "
1301 "(%lu.%02lu BogoMIPS).\n",
1302 (long) num_online_cpus(),
1303 bogosum/(500000/HZ),
1304 (bogosum/(5000/HZ))%100);
1307 void smp_send_reschedule(int cpu)
1309 smp_receive_signal(cpu);
1312 /* This is a nop because we capture all other cpus
1313 * anyways when making the PROM active.
1315 void smp_send_stop(void)
1319 unsigned long __per_cpu_base __read_mostly;
1320 unsigned long __per_cpu_shift __read_mostly;
1322 EXPORT_SYMBOL(__per_cpu_base);
1323 EXPORT_SYMBOL(__per_cpu_shift);
1325 void __init setup_per_cpu_areas(void)
1327 unsigned long goal, size, i;
1330 /* Copy section for each CPU (we discard the original) */
1331 goal = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
1332 #ifdef CONFIG_MODULES
1333 if (goal < PERCPU_ENOUGH_ROOM)
1334 goal = PERCPU_ENOUGH_ROOM;
1336 __per_cpu_shift = 0;
1337 for (size = 1UL; size < goal; size <<= 1UL)
1340 ptr = alloc_bootmem(size * NR_CPUS);
1342 __per_cpu_base = ptr - __per_cpu_start;
1344 for (i = 0; i < NR_CPUS; i++, ptr += size)
1345 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);