blob: f4ab233201b296013c7c45511a953838d29226d8 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/arch/alpha/kernel/smp.c
3 *
4 * 2001-07-09 Phil Ezolt (Phillip.Ezolt@compaq.com)
5 * Renamed modified smp_call_function to smp_call_function_on_cpu()
6 * Created an function that conforms to the old calling convention
7 * of smp_call_function().
8 *
9 * This is helpful for DCPI.
10 *
11 */
12
13#include <linux/errno.h>
14#include <linux/kernel.h>
15#include <linux/kernel_stat.h>
16#include <linux/module.h>
17#include <linux/sched.h>
18#include <linux/mm.h>
Alexey Dobriyan4e950f62007-07-30 02:36:13 +040019#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/threads.h>
21#include <linux/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/interrupt.h>
23#include <linux/init.h>
24#include <linux/delay.h>
25#include <linux/spinlock.h>
26#include <linux/irq.h>
27#include <linux/cache.h>
28#include <linux/profile.h>
29#include <linux/bitops.h>
30
31#include <asm/hwrpb.h>
32#include <asm/ptrace.h>
33#include <asm/atomic.h>
34
35#include <asm/io.h>
36#include <asm/irq.h>
37#include <asm/pgtable.h>
38#include <asm/pgalloc.h>
39#include <asm/mmu_context.h>
40#include <asm/tlbflush.h>
41
42#include "proto.h"
43#include "irq_impl.h"
44
45
46#define DEBUG_SMP 0
47#if DEBUG_SMP
48#define DBGS(args) printk args
49#else
50#define DBGS(args)
51#endif
52
53/* A collection of per-processor data. */
54struct cpuinfo_alpha cpu_data[NR_CPUS];
Al Virocff52da2006-10-11 17:40:22 +010055EXPORT_SYMBOL(cpu_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
57/* A collection of single bit ipi messages. */
58static struct {
59 unsigned long bits ____cacheline_aligned;
60} ipi_data[NR_CPUS] __cacheline_aligned;
61
62enum ipi_message_type {
63 IPI_RESCHEDULE,
64 IPI_CALL_FUNC,
65 IPI_CPU_STOP,
66};
67
68/* Set to a secondary's cpuid when it comes online. */
Al Virocc040a82007-07-17 08:49:35 +010069static int smp_secondary_alive __devinitdata = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070070
71/* Which cpus ids came online. */
Linus Torvalds1da177e2005-04-16 15:20:36 -070072cpumask_t cpu_online_map;
73
74EXPORT_SYMBOL(cpu_online_map);
75
Linus Torvalds1da177e2005-04-16 15:20:36 -070076int smp_num_probed; /* Internal processor count */
77int smp_num_cpus = 1; /* Number that came online. */
Al Virocff52da2006-10-11 17:40:22 +010078EXPORT_SYMBOL(smp_num_cpus);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
80extern void calibrate_delay(void);
81
82
83
84/*
85 * Called by both boot and secondaries to move global data into
86 * per-processor storage.
87 */
88static inline void __init
89smp_store_cpu_info(int cpuid)
90{
91 cpu_data[cpuid].loops_per_jiffy = loops_per_jiffy;
92 cpu_data[cpuid].last_asn = ASN_FIRST_VERSION;
93 cpu_data[cpuid].need_new_asn = 0;
94 cpu_data[cpuid].asn_lock = 0;
95}
96
97/*
98 * Ideally sets up per-cpu profiling hooks. Doesn't do much now...
99 */
100static inline void __init
101smp_setup_percpu_timer(int cpuid)
102{
103 cpu_data[cpuid].prof_counter = 1;
104 cpu_data[cpuid].prof_multiplier = 1;
105}
106
107static void __init
108wait_boot_cpu_to_stop(int cpuid)
109{
110 unsigned long stop = jiffies + 10*HZ;
111
112 while (time_before(jiffies, stop)) {
113 if (!smp_secondary_alive)
114 return;
115 barrier();
116 }
117
118 printk("wait_boot_cpu_to_stop: FAILED on CPU %d, hanging now\n", cpuid);
119 for (;;)
120 barrier();
121}
122
123/*
124 * Where secondaries begin a life of C.
125 */
126void __init
127smp_callin(void)
128{
129 int cpuid = hard_smp_processor_id();
130
131 if (cpu_test_and_set(cpuid, cpu_online_map)) {
132 printk("??, cpu 0x%x already present??\n", cpuid);
133 BUG();
134 }
135
136 /* Turn on machine checks. */
137 wrmces(7);
138
139 /* Set trap vectors. */
140 trap_init();
141
142 /* Set interrupt vector. */
143 wrent(entInt, 0);
144
145 /* Get our local ticker going. */
146 smp_setup_percpu_timer(cpuid);
147
148 /* Call platform-specific callin, if specified */
149 if (alpha_mv.smp_callin) alpha_mv.smp_callin();
150
151 /* All kernel threads share the same mm context. */
152 atomic_inc(&init_mm.mm_count);
153 current->active_mm = &init_mm;
154
155 /* Must have completely accurate bogos. */
156 local_irq_enable();
157
158 /* Wait boot CPU to stop with irq enabled before running
159 calibrate_delay. */
160 wait_boot_cpu_to_stop(cpuid);
161 mb();
162 calibrate_delay();
163
164 smp_store_cpu_info(cpuid);
165 /* Allow master to continue only after we written loops_per_jiffy. */
166 wmb();
167 smp_secondary_alive = 1;
168
169 DBGS(("smp_callin: commencing CPU %d current %p active_mm %p\n",
170 cpuid, current, current->active_mm));
171
172 /* Do nothing. */
173 cpu_idle();
174}
175
176/* Wait until hwrpb->txrdy is clear for cpu. Return -1 on timeout. */
Al Virocc040a82007-07-17 08:49:35 +0100177static int __devinit
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178wait_for_txrdy (unsigned long cpumask)
179{
180 unsigned long timeout;
181
182 if (!(hwrpb->txrdy & cpumask))
183 return 0;
184
185 timeout = jiffies + 10*HZ;
186 while (time_before(jiffies, timeout)) {
187 if (!(hwrpb->txrdy & cpumask))
188 return 0;
189 udelay(10);
190 barrier();
191 }
192
193 return -1;
194}
195
196/*
197 * Send a message to a secondary's console. "START" is one such
198 * interesting message. ;-)
199 */
200static void __init
201send_secondary_console_msg(char *str, int cpuid)
202{
203 struct percpu_struct *cpu;
204 register char *cp1, *cp2;
205 unsigned long cpumask;
206 size_t len;
207
208 cpu = (struct percpu_struct *)
209 ((char*)hwrpb
210 + hwrpb->processor_offset
211 + cpuid * hwrpb->processor_size);
212
213 cpumask = (1UL << cpuid);
214 if (wait_for_txrdy(cpumask))
215 goto timeout;
216
217 cp2 = str;
218 len = strlen(cp2);
219 *(unsigned int *)&cpu->ipc_buffer[0] = len;
220 cp1 = (char *) &cpu->ipc_buffer[1];
221 memcpy(cp1, cp2, len);
222
223 /* atomic test and set */
224 wmb();
225 set_bit(cpuid, &hwrpb->rxrdy);
226
227 if (wait_for_txrdy(cpumask))
228 goto timeout;
229 return;
230
231 timeout:
232 printk("Processor %x not ready\n", cpuid);
233}
234
235/*
236 * A secondary console wants to send a message. Receive it.
237 */
238static void
239recv_secondary_console_msg(void)
240{
241 int mycpu, i, cnt;
242 unsigned long txrdy = hwrpb->txrdy;
243 char *cp1, *cp2, buf[80];
244 struct percpu_struct *cpu;
245
246 DBGS(("recv_secondary_console_msg: TXRDY 0x%lx.\n", txrdy));
247
248 mycpu = hard_smp_processor_id();
249
250 for (i = 0; i < NR_CPUS; i++) {
251 if (!(txrdy & (1UL << i)))
252 continue;
253
254 DBGS(("recv_secondary_console_msg: "
255 "TXRDY contains CPU %d.\n", i));
256
257 cpu = (struct percpu_struct *)
258 ((char*)hwrpb
259 + hwrpb->processor_offset
260 + i * hwrpb->processor_size);
261
262 DBGS(("recv_secondary_console_msg: on %d from %d"
263 " HALT_REASON 0x%lx FLAGS 0x%lx\n",
264 mycpu, i, cpu->halt_reason, cpu->flags));
265
266 cnt = cpu->ipc_buffer[0] >> 32;
267 if (cnt <= 0 || cnt >= 80)
268 strcpy(buf, "<<< BOGUS MSG >>>");
269 else {
270 cp1 = (char *) &cpu->ipc_buffer[11];
271 cp2 = buf;
272 strcpy(cp2, cp1);
273
274 while ((cp2 = strchr(cp2, '\r')) != 0) {
275 *cp2 = ' ';
276 if (cp2[1] == '\n')
277 cp2[1] = ' ';
278 }
279 }
280
281 DBGS((KERN_INFO "recv_secondary_console_msg: on %d "
282 "message is '%s'\n", mycpu, buf));
283 }
284
285 hwrpb->txrdy = 0;
286}
287
288/*
289 * Convince the console to have a secondary cpu begin execution.
290 */
291static int __init
292secondary_cpu_start(int cpuid, struct task_struct *idle)
293{
294 struct percpu_struct *cpu;
295 struct pcb_struct *hwpcb, *ipcb;
296 unsigned long timeout;
297
298 cpu = (struct percpu_struct *)
299 ((char*)hwrpb
300 + hwrpb->processor_offset
301 + cpuid * hwrpb->processor_size);
302 hwpcb = (struct pcb_struct *) cpu->hwpcb;
Al Viro37bfbaf2006-01-12 01:05:36 -0800303 ipcb = &task_thread_info(idle)->pcb;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
305 /* Initialize the CPU's HWPCB to something just good enough for
306 us to get started. Immediately after starting, we'll swpctx
307 to the target idle task's pcb. Reuse the stack in the mean
308 time. Precalculate the target PCBB. */
309 hwpcb->ksp = (unsigned long)ipcb + sizeof(union thread_union) - 16;
310 hwpcb->usp = 0;
311 hwpcb->ptbr = ipcb->ptbr;
312 hwpcb->pcc = 0;
313 hwpcb->asn = 0;
314 hwpcb->unique = virt_to_phys(ipcb);
315 hwpcb->flags = ipcb->flags;
316 hwpcb->res1 = hwpcb->res2 = 0;
317
318#if 0
319 DBGS(("KSP 0x%lx PTBR 0x%lx VPTBR 0x%lx UNIQUE 0x%lx\n",
320 hwpcb->ksp, hwpcb->ptbr, hwrpb->vptb, hwpcb->unique));
321#endif
322 DBGS(("Starting secondary cpu %d: state 0x%lx pal_flags 0x%lx\n",
323 cpuid, idle->state, ipcb->flags));
324
325 /* Setup HWRPB fields that SRM uses to activate secondary CPU */
326 hwrpb->CPU_restart = __smp_callin;
327 hwrpb->CPU_restart_data = (unsigned long) __smp_callin;
328
329 /* Recalculate and update the HWRPB checksum */
330 hwrpb_update_checksum(hwrpb);
331
332 /*
333 * Send a "start" command to the specified processor.
334 */
335
336 /* SRM III 3.4.1.3 */
337 cpu->flags |= 0x22; /* turn on Context Valid and Restart Capable */
338 cpu->flags &= ~1; /* turn off Bootstrap In Progress */
339 wmb();
340
341 send_secondary_console_msg("START\r\n", cpuid);
342
343 /* Wait 10 seconds for an ACK from the console. */
344 timeout = jiffies + 10*HZ;
345 while (time_before(jiffies, timeout)) {
346 if (cpu->flags & 1)
347 goto started;
348 udelay(10);
349 barrier();
350 }
351 printk(KERN_ERR "SMP: Processor %d failed to start.\n", cpuid);
352 return -1;
353
354 started:
355 DBGS(("secondary_cpu_start: SUCCESS for CPU %d!!!\n", cpuid));
356 return 0;
357}
358
359/*
360 * Bring one cpu online.
361 */
Al Viroed5f6562007-07-26 17:34:19 +0100362static int __cpuinit
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363smp_boot_one_cpu(int cpuid)
364{
365 struct task_struct *idle;
366 unsigned long timeout;
367
368 /* Cook up an idler for this guy. Note that the address we
369 give to kernel_thread is irrelevant -- it's going to start
370 where HWRPB.CPU_restart says to start. But this gets all
371 the other task-y sort of data structures set up like we
372 wish. We can't use kernel_thread since we must avoid
373 rescheduling the child. */
374 idle = fork_idle(cpuid);
375 if (IS_ERR(idle))
376 panic("failed fork for CPU %d", cpuid);
377
378 DBGS(("smp_boot_one_cpu: CPU %d state 0x%lx flags 0x%lx\n",
379 cpuid, idle->state, idle->flags));
380
381 /* Signal the secondary to wait a moment. */
382 smp_secondary_alive = -1;
383
384 /* Whirrr, whirrr, whirrrrrrrrr... */
385 if (secondary_cpu_start(cpuid, idle))
386 return -1;
387
388 /* Notify the secondary CPU it can run calibrate_delay. */
389 mb();
390 smp_secondary_alive = 0;
391
392 /* We've been acked by the console; wait one second for
393 the task to start up for real. */
394 timeout = jiffies + 1*HZ;
395 while (time_before(jiffies, timeout)) {
396 if (smp_secondary_alive == 1)
397 goto alive;
398 udelay(10);
399 barrier();
400 }
401
402 /* We failed to boot the CPU. */
403
404 printk(KERN_ERR "SMP: Processor %d is stuck.\n", cpuid);
405 return -1;
406
407 alive:
408 /* Another "Red Snapper". */
409 return 0;
410}
411
412/*
413 * Called from setup_arch. Detect an SMP system and which processors
414 * are present.
415 */
416void __init
417setup_smp(void)
418{
419 struct percpu_struct *cpubase, *cpu;
420 unsigned long i;
421
422 if (boot_cpuid != 0) {
423 printk(KERN_WARNING "SMP: Booting off cpu %d instead of 0?\n",
424 boot_cpuid);
425 }
426
427 if (hwrpb->nr_processors > 1) {
428 int boot_cpu_palrev;
429
430 DBGS(("setup_smp: nr_processors %ld\n",
431 hwrpb->nr_processors));
432
433 cpubase = (struct percpu_struct *)
434 ((char*)hwrpb + hwrpb->processor_offset);
435 boot_cpu_palrev = cpubase->pal_revision;
436
437 for (i = 0; i < hwrpb->nr_processors; i++) {
438 cpu = (struct percpu_struct *)
439 ((char *)cpubase + i*hwrpb->processor_size);
440 if ((cpu->flags & 0x1cc) == 0x1cc) {
441 smp_num_probed++;
Ivan Kokshayskyc7d2d282006-06-04 02:51:34 -0700442 cpu_set(i, cpu_present_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 cpu->pal_revision = boot_cpu_palrev;
444 }
445
446 DBGS(("setup_smp: CPU %d: flags 0x%lx type 0x%lx\n",
447 i, cpu->flags, cpu->type));
448 DBGS(("setup_smp: CPU %d: PAL rev 0x%lx\n",
449 i, cpu->pal_revision));
450 }
451 } else {
452 smp_num_probed = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
Ivan Kokshayskyc7d2d282006-06-04 02:51:34 -0700455 printk(KERN_INFO "SMP: %d CPUs probed -- cpu_present_map = %lx\n",
456 smp_num_probed, cpu_present_map.bits[0]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457}
458
459/*
460 * Called by smp_init prepare the secondaries
461 */
462void __init
463smp_prepare_cpus(unsigned int max_cpus)
464{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 /* Take care of some initial bookkeeping. */
466 memset(ipi_data, 0, sizeof(ipi_data));
467
468 current_thread_info()->cpu = boot_cpuid;
469
470 smp_store_cpu_info(boot_cpuid);
471 smp_setup_percpu_timer(boot_cpuid);
472
473 /* Nothing to do on a UP box, or when told not to. */
474 if (smp_num_probed == 1 || max_cpus == 0) {
Ivan Kokshayskyc7d2d282006-06-04 02:51:34 -0700475 cpu_present_map = cpumask_of_cpu(boot_cpuid);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476 printk(KERN_INFO "SMP mode deactivated.\n");
477 return;
478 }
479
480 printk(KERN_INFO "SMP starting up secondaries.\n");
481
Ivan Kokshaysky328c2a82006-02-08 11:55:06 +0300482 smp_num_cpus = smp_num_probed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483}
484
485void __devinit
486smp_prepare_boot_cpu(void)
487{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488}
489
Al Viroed5f6562007-07-26 17:34:19 +0100490int __cpuinit
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491__cpu_up(unsigned int cpu)
492{
493 smp_boot_one_cpu(cpu);
494
495 return cpu_online(cpu) ? 0 : -ENOSYS;
496}
497
498void __init
499smp_cpus_done(unsigned int max_cpus)
500{
501 int cpu;
502 unsigned long bogosum = 0;
503
504 for(cpu = 0; cpu < NR_CPUS; cpu++)
505 if (cpu_online(cpu))
506 bogosum += cpu_data[cpu].loops_per_jiffy;
507
508 printk(KERN_INFO "SMP: Total of %d processors activated "
509 "(%lu.%02lu BogoMIPS).\n",
510 num_online_cpus(),
511 (bogosum + 2500) / (500000/HZ),
512 ((bogosum + 2500) / (5000/HZ)) % 100);
513}
514
515
516void
517smp_percpu_timer_interrupt(struct pt_regs *regs)
518{
Al Viro8774cb82006-10-07 14:17:31 +0100519 struct pt_regs *old_regs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520 int cpu = smp_processor_id();
521 unsigned long user = user_mode(regs);
522 struct cpuinfo_alpha *data = &cpu_data[cpu];
523
Al Viro8774cb82006-10-07 14:17:31 +0100524 old_regs = set_irq_regs(regs);
525
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 /* Record kernel PC. */
Al Viro8774cb82006-10-07 14:17:31 +0100527 profile_tick(CPU_PROFILING);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700528
529 if (!--data->prof_counter) {
530 /* We need to make like a normal interrupt -- otherwise
531 timer interrupts ignore the global interrupt lock,
532 which would be a Bad Thing. */
533 irq_enter();
534
535 update_process_times(user);
536
537 data->prof_counter = data->prof_multiplier;
538
539 irq_exit();
540 }
Al Viro8774cb82006-10-07 14:17:31 +0100541 set_irq_regs(old_regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542}
543
Al Viroed5f6562007-07-26 17:34:19 +0100544int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545setup_profiling_timer(unsigned int multiplier)
546{
547 return -EINVAL;
548}
549
550
551static void
552send_ipi_message(cpumask_t to_whom, enum ipi_message_type operation)
553{
554 int i;
555
556 mb();
557 for_each_cpu_mask(i, to_whom)
558 set_bit(operation, &ipi_data[i].bits);
559
560 mb();
561 for_each_cpu_mask(i, to_whom)
562 wripir(i);
563}
564
565/* Structure and data for smp_call_function. This is designed to
566 minimize static memory requirements. Plus it looks cleaner. */
567
568struct smp_call_struct {
569 void (*func) (void *info);
570 void *info;
571 long wait;
572 atomic_t unstarted_count;
573 atomic_t unfinished_count;
574};
575
576static struct smp_call_struct *smp_call_function_data;
577
578/* Atomicly drop data into a shared pointer. The pointer is free if
579 it is initially locked. If retry, spin until free. */
580
581static int
582pointer_lock (void *lock, void *data, int retry)
583{
584 void *old, *tmp;
585
586 mb();
587 again:
588 /* Compare and swap with zero. */
589 asm volatile (
590 "1: ldq_l %0,%1\n"
591 " mov %3,%2\n"
592 " bne %0,2f\n"
593 " stq_c %2,%1\n"
594 " beq %2,1b\n"
595 "2:"
596 : "=&r"(old), "=m"(*(void **)lock), "=&r"(tmp)
597 : "r"(data)
598 : "memory");
599
600 if (old == 0)
601 return 0;
602 if (! retry)
603 return -EBUSY;
604
605 while (*(void **)lock)
606 barrier();
607 goto again;
608}
609
610void
611handle_ipi(struct pt_regs *regs)
612{
613 int this_cpu = smp_processor_id();
614 unsigned long *pending_ipis = &ipi_data[this_cpu].bits;
615 unsigned long ops;
616
617#if 0
618 DBGS(("handle_ipi: on CPU %d ops 0x%lx PC 0x%lx\n",
619 this_cpu, *pending_ipis, regs->pc));
620#endif
621
622 mb(); /* Order interrupt and bit testing. */
623 while ((ops = xchg(pending_ipis, 0)) != 0) {
624 mb(); /* Order bit clearing and data access. */
625 do {
626 unsigned long which;
627
628 which = ops & -ops;
629 ops &= ~which;
630 which = __ffs(which);
631
632 switch (which) {
633 case IPI_RESCHEDULE:
634 /* Reschedule callback. Everything to be done
635 is done by the interrupt return path. */
636 break;
637
638 case IPI_CALL_FUNC:
639 {
640 struct smp_call_struct *data;
641 void (*func)(void *info);
642 void *info;
643 int wait;
644
645 data = smp_call_function_data;
646 func = data->func;
647 info = data->info;
648 wait = data->wait;
649
650 /* Notify the sending CPU that the data has been
651 received, and execution is about to begin. */
652 mb();
653 atomic_dec (&data->unstarted_count);
654
655 /* At this point the structure may be gone unless
656 wait is true. */
657 (*func)(info);
658
659 /* Notify the sending CPU that the task is done. */
660 mb();
661 if (wait) atomic_dec (&data->unfinished_count);
662 break;
663 }
664
665 case IPI_CPU_STOP:
666 halt();
667
668 default:
669 printk(KERN_CRIT "Unknown IPI on CPU %d: %lu\n",
670 this_cpu, which);
671 break;
672 }
673 } while (ops);
674
675 mb(); /* Order data access and bit testing. */
676 }
677
678 cpu_data[this_cpu].ipi_count++;
679
680 if (hwrpb->txrdy)
681 recv_secondary_console_msg();
682}
683
684void
685smp_send_reschedule(int cpu)
686{
687#ifdef DEBUG_IPI_MSG
688 if (cpu == hard_smp_processor_id())
689 printk(KERN_WARNING
690 "smp_send_reschedule: Sending IPI to self.\n");
691#endif
692 send_ipi_message(cpumask_of_cpu(cpu), IPI_RESCHEDULE);
693}
694
695void
696smp_send_stop(void)
697{
698 cpumask_t to_whom = cpu_possible_map;
699 cpu_clear(smp_processor_id(), to_whom);
700#ifdef DEBUG_IPI_MSG
701 if (hard_smp_processor_id() != boot_cpu_id)
702 printk(KERN_WARNING "smp_send_stop: Not on boot cpu.\n");
703#endif
704 send_ipi_message(to_whom, IPI_CPU_STOP);
705}
706
707/*
708 * Run a function on all other CPUs.
709 * <func> The function to run. This must be fast and non-blocking.
710 * <info> An arbitrary pointer to pass to the function.
711 * <retry> If true, keep retrying until ready.
712 * <wait> If true, wait until function has completed on other CPUs.
713 * [RETURNS] 0 on success, else a negative status code.
714 *
715 * Does not return until remote CPUs are nearly ready to execute <func>
716 * or are or have executed.
717 * You must not call this function with disabled interrupts or from a
718 * hardware interrupt handler or from a bottom half handler.
719 */
720
721int
722smp_call_function_on_cpu (void (*func) (void *info), void *info, int retry,
723 int wait, cpumask_t to_whom)
724{
725 struct smp_call_struct data;
726 unsigned long timeout;
727 int num_cpus_to_call;
728
729 /* Can deadlock when called with interrupts disabled */
730 WARN_ON(irqs_disabled());
731
732 data.func = func;
733 data.info = info;
734 data.wait = wait;
735
736 cpu_clear(smp_processor_id(), to_whom);
737 num_cpus_to_call = cpus_weight(to_whom);
738
739 atomic_set(&data.unstarted_count, num_cpus_to_call);
740 atomic_set(&data.unfinished_count, num_cpus_to_call);
741
742 /* Acquire the smp_call_function_data mutex. */
743 if (pointer_lock(&smp_call_function_data, &data, retry))
744 return -EBUSY;
745
746 /* Send a message to the requested CPUs. */
747 send_ipi_message(to_whom, IPI_CALL_FUNC);
748
749 /* Wait for a minimal response. */
750 timeout = jiffies + HZ;
751 while (atomic_read (&data.unstarted_count) > 0
752 && time_before (jiffies, timeout))
753 barrier();
754
755 /* If there's no response yet, log a message but allow a longer
756 * timeout period -- if we get a response this time, log
757 * a message saying when we got it..
758 */
759 if (atomic_read(&data.unstarted_count) > 0) {
760 long start_time = jiffies;
761 printk(KERN_ERR "%s: initial timeout -- trying long wait\n",
762 __FUNCTION__);
763 timeout = jiffies + 30 * HZ;
764 while (atomic_read(&data.unstarted_count) > 0
765 && time_before(jiffies, timeout))
766 barrier();
767 if (atomic_read(&data.unstarted_count) <= 0) {
768 long delta = jiffies - start_time;
769 printk(KERN_ERR
770 "%s: response %ld.%ld seconds into long wait\n",
771 __FUNCTION__, delta / HZ,
772 (100 * (delta - ((delta / HZ) * HZ))) / HZ);
773 }
774 }
775
776 /* We either got one or timed out -- clear the lock. */
777 mb();
778 smp_call_function_data = NULL;
779
780 /*
781 * If after both the initial and long timeout periods we still don't
782 * have a response, something is very wrong...
783 */
784 BUG_ON(atomic_read (&data.unstarted_count) > 0);
785
786 /* Wait for a complete response, if needed. */
787 if (wait) {
788 while (atomic_read (&data.unfinished_count) > 0)
789 barrier();
790 }
791
792 return 0;
793}
Al Virocff52da2006-10-11 17:40:22 +0100794EXPORT_SYMBOL(smp_call_function_on_cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795
796int
797smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
798{
799 return smp_call_function_on_cpu (func, info, retry, wait,
800 cpu_online_map);
801}
Al Virocff52da2006-10-11 17:40:22 +0100802EXPORT_SYMBOL(smp_call_function);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803
804static void
805ipi_imb(void *ignored)
806{
807 imb();
808}
809
810void
811smp_imb(void)
812{
813 /* Must wait other processors to flush their icache before continue. */
814 if (on_each_cpu(ipi_imb, NULL, 1, 1))
815 printk(KERN_CRIT "smp_imb: timed out\n");
816}
Al Virocff52da2006-10-11 17:40:22 +0100817EXPORT_SYMBOL(smp_imb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
819static void
820ipi_flush_tlb_all(void *ignored)
821{
822 tbia();
823}
824
825void
826flush_tlb_all(void)
827{
828 /* Although we don't have any data to pass, we do want to
829 synchronize with the other processors. */
830 if (on_each_cpu(ipi_flush_tlb_all, NULL, 1, 1)) {
831 printk(KERN_CRIT "flush_tlb_all: timed out\n");
832 }
833}
834
835#define asn_locked() (cpu_data[smp_processor_id()].asn_lock)
836
837static void
838ipi_flush_tlb_mm(void *x)
839{
840 struct mm_struct *mm = (struct mm_struct *) x;
841 if (mm == current->active_mm && !asn_locked())
842 flush_tlb_current(mm);
843 else
844 flush_tlb_other(mm);
845}
846
847void
848flush_tlb_mm(struct mm_struct *mm)
849{
850 preempt_disable();
851
852 if (mm == current->active_mm) {
853 flush_tlb_current(mm);
854 if (atomic_read(&mm->mm_users) <= 1) {
855 int cpu, this_cpu = smp_processor_id();
856 for (cpu = 0; cpu < NR_CPUS; cpu++) {
857 if (!cpu_online(cpu) || cpu == this_cpu)
858 continue;
859 if (mm->context[cpu])
860 mm->context[cpu] = 0;
861 }
862 preempt_enable();
863 return;
864 }
865 }
866
867 if (smp_call_function(ipi_flush_tlb_mm, mm, 1, 1)) {
868 printk(KERN_CRIT "flush_tlb_mm: timed out\n");
869 }
870
871 preempt_enable();
872}
Al Virocff52da2006-10-11 17:40:22 +0100873EXPORT_SYMBOL(flush_tlb_mm);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874
875struct flush_tlb_page_struct {
876 struct vm_area_struct *vma;
877 struct mm_struct *mm;
878 unsigned long addr;
879};
880
881static void
882ipi_flush_tlb_page(void *x)
883{
884 struct flush_tlb_page_struct *data = (struct flush_tlb_page_struct *)x;
885 struct mm_struct * mm = data->mm;
886
887 if (mm == current->active_mm && !asn_locked())
888 flush_tlb_current_page(mm, data->vma, data->addr);
889 else
890 flush_tlb_other(mm);
891}
892
893void
894flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
895{
896 struct flush_tlb_page_struct data;
897 struct mm_struct *mm = vma->vm_mm;
898
899 preempt_disable();
900
901 if (mm == current->active_mm) {
902 flush_tlb_current_page(mm, vma, addr);
903 if (atomic_read(&mm->mm_users) <= 1) {
904 int cpu, this_cpu = smp_processor_id();
905 for (cpu = 0; cpu < NR_CPUS; cpu++) {
906 if (!cpu_online(cpu) || cpu == this_cpu)
907 continue;
908 if (mm->context[cpu])
909 mm->context[cpu] = 0;
910 }
911 preempt_enable();
912 return;
913 }
914 }
915
916 data.vma = vma;
917 data.mm = mm;
918 data.addr = addr;
919
920 if (smp_call_function(ipi_flush_tlb_page, &data, 1, 1)) {
921 printk(KERN_CRIT "flush_tlb_page: timed out\n");
922 }
923
924 preempt_enable();
925}
Al Virocff52da2006-10-11 17:40:22 +0100926EXPORT_SYMBOL(flush_tlb_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927
928void
929flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
930{
931 /* On the Alpha we always flush the whole user tlb. */
932 flush_tlb_mm(vma->vm_mm);
933}
Al Virocff52da2006-10-11 17:40:22 +0100934EXPORT_SYMBOL(flush_tlb_range);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935
936static void
937ipi_flush_icache_page(void *x)
938{
939 struct mm_struct *mm = (struct mm_struct *) x;
940 if (mm == current->active_mm && !asn_locked())
941 __load_new_mm_context(mm);
942 else
943 flush_tlb_other(mm);
944}
945
946void
947flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
948 unsigned long addr, int len)
949{
950 struct mm_struct *mm = vma->vm_mm;
951
952 if ((vma->vm_flags & VM_EXEC) == 0)
953 return;
954
955 preempt_disable();
956
957 if (mm == current->active_mm) {
958 __load_new_mm_context(mm);
959 if (atomic_read(&mm->mm_users) <= 1) {
960 int cpu, this_cpu = smp_processor_id();
961 for (cpu = 0; cpu < NR_CPUS; cpu++) {
962 if (!cpu_online(cpu) || cpu == this_cpu)
963 continue;
964 if (mm->context[cpu])
965 mm->context[cpu] = 0;
966 }
967 preempt_enable();
968 return;
969 }
970 }
971
972 if (smp_call_function(ipi_flush_icache_page, mm, 1, 1)) {
973 printk(KERN_CRIT "flush_icache_page: timed out\n");
974 }
975
976 preempt_enable();
977}