arch/sparc/kernel/smp.c

/* */
This source file includes following definitions.
smp_info
swap
smp_store_cpu_info
smp_commence
smp_callin
cpu_panic
smp_boot_cpus
send_ipi
smp_message_pass
smp_cross_call
smp_flush_cache_all
smp_flush_tlb_all
smp_flush_cache_mm
smp_flush_tlb_mm
smp_flush_cache_range
smp_flush_tlb_range
smp_flush_cache_page
smp_flush_tlb_page
smp_flush_page_to_ram
smp_reschedule_irq
smp_capture
smp_release
smp_message_irq
   1 /* smp.c: Sparc SMP support.
   2  *
   3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   4  */
   5 
   6 #include <asm/head.h>
   7 #include <asm/ptrace.h>
   8 
   9 #include <linux/kernel.h>
  10 #include <linux/tasks.h>
  11 #include <linux/smp.h>
  12 
  13 #include <asm/delay.h>
  14 #include <asm/irq.h>
  15 #include <asm/page.h>
  16 #include <asm/pgtable.h>
  17 #include <asm/oplib.h>
  18 
  19 extern ctxd_t *srmmu_ctx_table_phys;
  20 extern int linux_num_cpus;
  21 
  22 struct tlog {
  23         unsigned long pc;
  24         unsigned long psr;
  25 };
  26 
  27 struct tlog trap_log[4][256];
  28 unsigned long trap_log_ent[4] = { 0, 0, 0, 0, };
  29 
  30 extern void calibrate_delay(void);
  31 
  32 volatile unsigned long stuck_pc = 0;
  33 volatile int smp_processors_ready = 0;
  34 
  35 int smp_found_config = 0;
  36 unsigned long cpu_present_map = 0;
  37 int smp_num_cpus = 1;
  38 int smp_threads_ready=0;
  39 unsigned char mid_xlate[NR_CPUS] = { 0, 0, 0, 0, };
  40 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,};
  41 volatile unsigned long smp_invalidate_needed[NR_CPUS] = { 0, };
  42 volatile unsigned long smp_spinning[NR_CPUS] = { 0, };
  43 struct cpuinfo_sparc cpu_data[NR_CPUS];
  44 unsigned char boot_cpu_id = 0;
  45 static int smp_activated = 0;
  46 static volatile unsigned char smp_cpu_in_msg[NR_CPUS];
  47 static volatile unsigned long smp_msg_data;
  48 static volatile int smp_src_cpu;
  49 static volatile int smp_msg_id;
  50 volatile int cpu_number_map[NR_CPUS];
  51 volatile int cpu_logical_map[NR_CPUS];
  52 
  53 /* The only guaranteed locking primitive available on all Sparc
  54  * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
  55  * places the current byte at the effective address into dest_reg and
  56  * places 0xff there afterwards.  Pretty lame locking primitive
  57  * compared to the Alpha and the intel no?  Most Sparcs have 'swap'
  58  * instruction which is much better...
  59  */
  60 klock_t kernel_flag = KLOCK_CLEAR;
  61 volatile unsigned char active_kernel_processor = NO_PROC_ID;
  62 volatile unsigned long kernel_counter = 0;
  63 volatile unsigned long syscall_count = 0;
  64 volatile unsigned long ipi_count;
  65 #ifdef __SMP_PROF__
  66 volatile unsigned long smp_spins[NR_CPUS]={0};
  67 volatile unsigned long smp_spins_syscall[NR_CPUS]={0};
  68 volatile unsigned long smp_spins_syscall_cur[NR_CPUS]={0};
  69 volatile unsigned long smp_spins_sys_idle[NR_CPUS]={0};
  70 volatile unsigned long smp_idle_count[1+NR_CPUS]={0,};
  71 #endif
  72 #if defined (__SMP_PROF__)
  73 volatile unsigned long smp_idle_map=0;
  74 #endif
  75 
  76 volatile unsigned long smp_proc_in_lock[NR_CPUS] = {0,};
  77 volatile int smp_process_available=0;
  78 
  79 /*#define SMP_DEBUG*/
  80 
  81 #ifdef SMP_DEBUG
  82 #define SMP_PRINTK(x)   printk x
  83 #else
  84 #define SMP_PRINTK(x)
  85 #endif
  86 
  87 static volatile int smp_commenced = 0;
  88 
  89 static char smp_buf[512];
  90 
  91 char *smp_info(void)
     /*  */
  92 {
  93         sprintf(smp_buf,
  94 "\n        CPU0\t\tCPU1\t\tCPU2\t\tCPU3\n"
  95 "State: %s\t\t%s\t\t%s\t\t%s\n"
  96 "Lock:  %08lx\t\t%08lx\t%08lx\t%08lx\n"
  97 "\n"
  98 "klock: %x\n",
  99                 (cpu_present_map & 1) ? ((active_kernel_processor == 0) ? "akp" : "online") : "offline",
 100                 (cpu_present_map & 2) ? ((active_kernel_processor == 1) ? "akp" : "online") : "offline",
 101                 (cpu_present_map & 4) ? ((active_kernel_processor == 2) ? "akp" : "online") : "offline",
 102                 (cpu_present_map & 8) ? ((active_kernel_processor == 3) ? "akp" : "online") : "offline",
 103                 smp_proc_in_lock[0], smp_proc_in_lock[1], smp_proc_in_lock[2],
 104                 smp_proc_in_lock[3], 
 105                 kernel_flag);
 106         return smp_buf;
 107 }
 108 
 109 static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
     /*  */
 110 {
 111         __asm__ __volatile__("swap [%1], %0\n\t" :
 112                              "=&r" (val), "=&r" (ptr) :
 113                              "0" (val), "1" (ptr));
 114         return val;
 115 }
 116 
 117 /*
 118  *      The bootstrap kernel entry code has set these up. Save them for
 119  *      a given CPU
 120  */
 121 
 122 void smp_store_cpu_info(int id)
     /*  */
 123 {
 124         cpu_data[id].udelay_val = loops_per_sec; /* this is it on sparc. */
 125 }
 126 
 127 /*
 128  *      Architecture specific routine called by the kernel just before init is
 129  *      fired off. This allows the BP to have everything in order [we hope].
 130  *      At the end of this all the AP's will hit the system scheduling and off
 131  *      we go. Each AP will load the system gdt's and jump through the kernel
 132  *      init into idle(). At this point the scheduler will one day take over 
 133  *      and give them jobs to do. smp_callin is a standard routine
 134  *      we use to track CPU's as they power up.
 135  */
 136 
 137 void smp_commence(void)
     /*  */
 138 {
 139         /*
 140          *      Lets the callin's below out of their loop.
 141          */
 142         local_flush_cache_all();
 143         local_flush_tlb_all();
 144         smp_commenced = 1;
 145         local_flush_cache_all();
 146         local_flush_tlb_all();
 147 }
 148 
 149 void smp_callin(void)
     /*  */
 150 {
 151         int cpuid = smp_processor_id();
 152 
 153         sti();
 154         local_flush_cache_all();
 155         local_flush_tlb_all();
 156         calibrate_delay();
 157         smp_store_cpu_info(cpuid);
 158         local_flush_cache_all();
 159         local_flush_tlb_all();
 160         cli();
 161 
 162         /* Allow master to continue. */
 163         swap((unsigned long *)&cpu_callin_map[cpuid], 1);
 164         local_flush_cache_all();
 165         local_flush_tlb_all();
 166         while(!smp_commenced)
 167                 barrier();
 168         local_flush_cache_all();
 169         local_flush_tlb_all();
 170 
 171         /* Fix idle thread fields. */
 172         current->mm->mmap->vm_page_prot = PAGE_SHARED;
 173         current->mm->mmap->vm_start = KERNBASE;
 174         current->mm->mmap->vm_end = init_task.mm->mmap->vm_end;
 175 
 176         local_flush_cache_all();
 177         local_flush_tlb_all();
 178 
 179         sti();
 180 }
 181 
 182 void cpu_panic(void)
     /*  */
 183 {
 184         printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
 185         panic("SMP bolixed\n");
 186 }
 187 
 188 /*
 189  *      Cycle through the processors asking the PROM to start each one.
 190  */
 191  
 192 extern struct prom_cpuinfo linux_cpus[NCPUS];
 193 static struct linux_prom_registers penguin_ctable;
 194 
 195 void smp_boot_cpus(void)
     /*  */
 196 {
 197         int cpucount = 0;
 198         int i = 0;
 199 
 200         printk("Entering SparclinuxMultiPenguin(SMP) Mode...\n");
 201 
 202         penguin_ctable.which_io = 0;
 203         penguin_ctable.phys_addr = (char *) srmmu_ctx_table_phys;
 204         penguin_ctable.reg_size = 0;
 205 
 206         sti();
 207         cpu_present_map |= (1 << smp_processor_id());
 208         cpu_present_map = 0;
 209         for(i=0; i < linux_num_cpus; i++)
 210                 cpu_present_map |= (1<<i);
 211         for(i=0; i < NR_CPUS; i++)
 212                 cpu_number_map[i] = -1;
 213         for(i=0; i < NR_CPUS; i++)
 214                 cpu_logical_map[i] = -1;
 215         mid_xlate[boot_cpu_id] = (linux_cpus[boot_cpu_id].mid & ~8);
 216         cpu_number_map[boot_cpu_id] = 0;
 217         cpu_logical_map[0] = boot_cpu_id;
 218         active_kernel_processor = boot_cpu_id;
 219         smp_store_cpu_info(boot_cpu_id);
 220         set_irq_udt(0);
 221         local_flush_cache_all();
 222         if(linux_num_cpus == 1)
 223                 return;  /* Not an MP box. */
 224         for(i = 0; i < NR_CPUS; i++) {
 225                 if(i == boot_cpu_id)
 226                         continue;
 227 
 228                 if(cpu_present_map & (1 << i)) {
 229                         extern unsigned long sparc_cpu_startup;
 230                         unsigned long *entry = &sparc_cpu_startup;
 231                         int timeout;
 232 
 233                         /* See trampoline.S for details... */
 234                         entry += ((i-1) * 6);
 235 
 236                         /* whirrr, whirrr, whirrrrrrrrr... */
 237                         printk("Starting CPU %d at %p\n", i, entry);
 238                         mid_xlate[i] = (linux_cpus[i].mid & ~8);
 239                         local_flush_cache_all();
 240                         prom_startcpu(linux_cpus[i].prom_node,
 241                                       &penguin_ctable, 0, (char *)entry);
 242 
 243                         /* wheee... it's going... */
 244                         for(timeout = 0; timeout < 5000000; timeout++) {
 245                                 if(cpu_callin_map[i])
 246                                         break;
 247                                 udelay(100);
 248                         }
 249                         if(cpu_callin_map[i]) {
 250                                 /* Another "Red Snapper". */
 251                                 cpucount++;
 252                                 cpu_number_map[i] = i;
 253                                 cpu_logical_map[i] = i;
 254                         } else {
 255                                 printk("Penguin %d is stuck in the bottle.\n", i);
 256                         }
 257                 }
 258                 if(!(cpu_callin_map[i])) {
 259                         cpu_present_map &= ~(1 << i);
 260                         cpu_number_map[i] = -1;
 261                 }
 262         }
 263         local_flush_cache_all();
 264         if(cpucount == 0) {
 265                 printk("Error: only one Penguin found.\n");
 266                 cpu_present_map = (1 << smp_processor_id());
 267         } else {
 268                 unsigned long bogosum = 0;
 269                 for(i = 0; i < NR_CPUS; i++) {
 270                         if(cpu_present_map & (1 << i))
 271                                 bogosum += cpu_data[i].udelay_val;
 272                 }
 273                 printk("Total of %d Penguins activated (%lu.%02lu PenguinMIPS).\n",
 274                        cpucount + 1,
 275                        (bogosum + 2500)/500000,
 276                        ((bogosum + 2500)/5000)%100);
 277                 smp_activated = 1;
 278                 smp_num_cpus = cpucount + 1;
 279         }
 280         smp_processors_ready = 1;
 281 }
 282 
 283 static inline void send_ipi(unsigned long target_map, int irq)
     /*  */
 284 {
 285         int i;
 286 
 287         for(i = 0; i < 4; i++) {
 288                 if((1<<i) & target_map)
 289                         set_cpu_int(mid_xlate[i], irq);
 290         }
 291 }
 292 
 293 /*
 294  * A non wait message cannot pass data or cpu source info. This current
 295  * setup is only safe because the kernel lock owner is the only person
 296  * who can send a message.
 297  *
 298  * Wrapping this whole block in a spinlock is not the safe answer either.
 299  * A processor may get stuck with irq's off waiting to send a message and
 300  * thus not replying to the person spinning for a reply....
 301  *
 302  * In the end invalidate ought to be the NMI and a very very short
 303  * function (to avoid the old IDE disk problems), and other messages sent
 304  * with IRQ's enabled in a civilised fashion. That will also boost
 305  * performance.
 306  */
 307 
 308 static volatile int message_cpu = NO_PROC_ID;
 309 
 310 void smp_message_pass(int target, int msg, unsigned long data, int wait)
     /*  */
 311 {
 312         unsigned long target_map;
 313         int p = smp_processor_id();
 314         int irq = 15;
 315         int i;
 316 
 317         /* Before processors have been placed into their initial
 318          * patterns do not send messages.
 319          */
 320         if(!smp_processors_ready)
 321                 return;
 322 
 323         /* Skip the reschedule if we are waiting to clear a
 324          * message at this time. The reschedule cannot wait
 325          * but is not critical.
 326          */
 327         if(msg == MSG_RESCHEDULE) {
 328                 irq = 13;
 329                 if(smp_cpu_in_msg[p])
 330                         return;
 331         }
 332 
 333         /* Sanity check we don't re-enter this across CPU's. Only the kernel
 334          * lock holder may send messages. For a STOP_CPU we are bringing the
 335          * entire box to the fastest halt we can.. A reschedule carries
 336          * no data and can occur during a flush.. guess what panic
 337          * I got to notice this bug...
 338          */
 339         if(message_cpu != NO_PROC_ID && msg != MSG_STOP_CPU && msg != MSG_RESCHEDULE) {
 340                 printk("CPU #%d: Message pass %d but pass in progress by %d of %d\n",
 341                       smp_processor_id(),msg,message_cpu, smp_msg_id);
 342 
 343                 /* I don't know how to gracefully die so that debugging
 344                  * this doesn't completely eat up my filesystems...
 345                  * let's try this...
 346                  */
 347                 smp_cpu_in_msg[p] = 0; /* In case we come back here... */
 348                 intr_count = 0;        /* and so panic don't barf... */
 349                 smp_swap(&message_cpu, NO_PROC_ID); /* push the store buffer */
 350                 sti();
 351                 printk("spinning, please L1-A, type ctrace and send output to davem\n");
 352                 while(1)
 353                         barrier();
 354         }
 355         smp_swap(&message_cpu, smp_processor_id()); /* store buffers... */
 356 
 357         /* We are busy. */
 358         smp_cpu_in_msg[p]++;
 359 
 360         /* Reschedule is currently special. */
 361         if(msg != MSG_RESCHEDULE) {
 362                 smp_src_cpu = p;
 363                 smp_msg_id = msg;
 364                 smp_msg_data = data;
 365         }
 366 
 367 #if 0
 368         printk("SMP message pass from cpu %d to cpu %d msg %d\n", p, target, msg);
 369 #endif
 370 
 371         /* Set the target requirement. */
 372         for(i = 0; i < smp_num_cpus; i++)
 373                 swap((unsigned long *) &cpu_callin_map[i], 0);
 374         if(target == MSG_ALL_BUT_SELF) {
 375                 target_map = (cpu_present_map & ~(1<<p));
 376                 swap((unsigned long *) &cpu_callin_map[p], 1);
 377         } else if(target == MSG_ALL) {
 378                 target_map = cpu_present_map;
 379         } else {
 380                 for(i = 0; i < smp_num_cpus; i++)
 381                         if(i != target)
 382                                 swap((unsigned long *) &cpu_callin_map[i], 1);
 383                 target_map = (1<<target);
 384         }
 385 
 386         /* Fire it off. */
 387         send_ipi(target_map, irq);
 388 
 389         switch(wait) {
 390         case 1:
 391                 for(i = 0; i < smp_num_cpus; i++)
 392                         while(!cpu_callin_map[i])
 393                                 barrier();
 394                 break;
 395         case 2:
 396                 for(i = 0; i < smp_num_cpus; i++)
 397                         while(smp_invalidate_needed[i])
 398                                 barrier();
 399                 break;
 400         case 3:
 401                 /* For cross calls we hold message_cpu and smp_cpu_in_msg[]
 402                  * until all processors disperse.  Else we have _big_ problems.
 403                  */
 404                 return;
 405         }
 406         smp_cpu_in_msg[p]--;
 407         smp_swap(&message_cpu, NO_PROC_ID);
 408 }
 409 
 410 struct smp_funcall {
 411         smpfunc_t func;
 412         unsigned long arg1;
 413         unsigned long arg2;
 414         unsigned long arg3;
 415         unsigned long arg4;
 416         unsigned long arg5;
 417         unsigned long processors_in[NR_CPUS];  /* Set when ipi entered. */
 418         unsigned long processors_out[NR_CPUS]; /* Set when ipi exited. */
 419 } ccall_info;
 420 
 421 /* Returns failure code if for example any of the cpu's failed to respond
 422  * within a certain timeout period.
 423  */
 424 
 425 #define CCALL_TIMEOUT   5000000 /* enough for initial testing */
 426 
 427 /* #define DEBUG_CCALL */
 428 
 429 /* Some nice day when we really thread the kernel I'd like to synchronize
 430  * this with either a broadcast conditional variable, a resource adaptive
 431  * generic mutex, or a convoy semaphore scheme of some sort.  No reason
 432  * we can't let multiple processors in here if the appropriate locking
 433  * is done.  Note that such a scheme assumes we will have a
 434  * prioritized ipi scheme using different software level irq's.
 435  */
 436 void smp_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
     /*  */
 437                     unsigned long arg3, unsigned long arg4, unsigned long arg5)
 438 {
 439         unsigned long me = smp_processor_id();
 440         unsigned long flags;
 441         int i, timeout;
 442 
 443 #ifdef DEBUG_CCALL
 444         printk("xc%d<", me);
 445 #endif
 446         if(smp_processors_ready) {
 447                 save_flags(flags); cli();
 448                 if(me != active_kernel_processor)
 449                         goto cross_call_not_master;
 450 
 451                 /* Init function glue. */
 452                 ccall_info.func = func;
 453                 ccall_info.arg1 = arg1;
 454                 ccall_info.arg2 = arg2;
 455                 ccall_info.arg3 = arg3;
 456                 ccall_info.arg4 = arg4;
 457                 ccall_info.arg5 = arg5;
 458 
 459                 /* Init receive/complete mapping. */
 460                 for(i = 0; i < smp_num_cpus; i++) {
 461                         ccall_info.processors_in[i] = 0;
 462                         ccall_info.processors_out[i] = 0;
 463                 }
 464                 ccall_info.processors_in[me] = 1;
 465                 ccall_info.processors_out[me] = 1;
 466 
 467                 /* Fire it off. */
 468                 smp_message_pass(MSG_ALL_BUT_SELF, MSG_CROSS_CALL, 0, 3);
 469 
 470                 /* For debugging purposes right now we can timeout
 471                  * on both callin and callexit.
 472                  */
 473                 timeout = CCALL_TIMEOUT;
 474                 for(i = 0; i < smp_num_cpus; i++) {
 475                         while(!ccall_info.processors_in[i] && timeout-- > 0)
 476                                 barrier();
 477                         if(!ccall_info.processors_in[i])
 478                                 goto procs_time_out;
 479                 }
 480 #ifdef DEBUG_CCALL
 481                 printk("I");
 482 #endif
 483 
 484                 /* Run local copy. */
 485                 func(arg1, arg2, arg3, arg4, arg5);
 486 
 487                 /* Spin on proc dispersion. */
 488                 timeout = CCALL_TIMEOUT;
 489                 for(i = 0; i < smp_num_cpus; i++) {
 490                         while(!ccall_info.processors_out[i] && timeout-- > 0)
 491                                 barrier();
 492                         if(!ccall_info.processors_out[i])
 493                                 goto procs_time_out;
 494                 }
 495 #ifdef DEBUG_CCALL
 496                 printk("O>");
 497 #endif
 498                 /* See wait case 3 in smp_message_pass()... */
 499                 smp_cpu_in_msg[me]--;
 500                 smp_swap(&message_cpu, NO_PROC_ID); /* store buffers... */
 501                 restore_flags(flags);
 502                 return; /* made it... */
 503 
 504 procs_time_out:
 505                 printk("smp: Wheee, penguin drops off the bus\n");
 506                 smp_cpu_in_msg[me]--;
 507                 message_cpu = NO_PROC_ID;
 508                 restore_flags(flags);
 509                 return; /* why me... why me... */
 510         }
 511 
 512         /* Just need to run local copy. */
 513         func(arg1, arg2, arg3, arg4, arg5);
 514         return;
 515 
 516 cross_call_not_master:
 517         printk("Cross call initiated by non master cpu\n");
 518         printk("akp=%x me=%08lx\n", active_kernel_processor, me);
 519         restore_flags(flags);
 520         panic("penguin cross call");
 521 }
 522 
 523 void smp_flush_cache_all(void)
     /*  */
 524 { xc0((smpfunc_t) local_flush_cache_all); }
 525 
 526 void smp_flush_tlb_all(void)
     /*  */
 527 { xc0((smpfunc_t) local_flush_tlb_all); }
 528 
 529 void smp_flush_cache_mm(struct mm_struct *mm)
     /*  */
 530 { 
 531         if(mm->context != NO_CONTEXT)
 532                 xc1((smpfunc_t) local_flush_cache_mm, (unsigned long) mm);
 533 }
 534 
 535 void smp_flush_tlb_mm(struct mm_struct *mm)
     /*  */
 536 {
 537         if(mm->context != NO_CONTEXT)
 538                 xc1((smpfunc_t) local_flush_tlb_mm, (unsigned long) mm);
 539 }
 540 
 541 void smp_flush_cache_range(struct mm_struct *mm, unsigned long start,
     /*  */
 542                            unsigned long end)
 543 {
 544         if(mm->context != NO_CONTEXT)
 545                 xc3((smpfunc_t) local_flush_cache_range, (unsigned long) mm,
 546                     start, end);
 547 }
 548 
 549 void smp_flush_tlb_range(struct mm_struct *mm, unsigned long start,
     /*  */
 550                          unsigned long end)
 551 {
 552         if(mm->context != NO_CONTEXT)
 553                 xc3((smpfunc_t) local_flush_tlb_range, (unsigned long) mm,
 554                     start, end);
 555 }
 556 
 557 void smp_flush_cache_page(struct vm_area_struct *vma, unsigned long page)
     /*  */
 558 { xc2((smpfunc_t) local_flush_cache_page, (unsigned long) vma, page); }
 559 
 560 void smp_flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
     /*  */
 561 { xc2((smpfunc_t) local_flush_tlb_page, (unsigned long) vma, page); }
 562 
 563 void smp_flush_page_to_ram(unsigned long page)
     /*  */
 564 { xc1((smpfunc_t) local_flush_page_to_ram, page); }
 565 
 566 /* Reschedule call back. */
 567 void smp_reschedule_irq(void)
     /*  */
 568 {
 569         if(smp_processor_id() != active_kernel_processor)
 570                 panic("SMP Reschedule on CPU #%d, but #%d is active.\n",
 571                       smp_processor_id(), active_kernel_processor);
 572 
 573         need_resched=1;
 574 }
 575 
 576 /* XXX FIXME: this still doesn't work right... XXX */
 577 
 578 /* #define DEBUG_CAPTURE */
 579 
 580 static volatile unsigned long release = 1;
 581 static volatile int capture_level = 0;
 582 
 583 void smp_capture(void)
     /*  */
 584 {
 585         unsigned long flags;
 586 
 587         if(!smp_activated || !smp_commenced)
 588                 return;
 589 #ifdef DEBUG_CAPTURE
 590         printk("C<%d>", smp_processor_id());
 591 #endif
 592         save_flags(flags); cli();
 593         if(!capture_level) {
 594                 release = 0;
 595                 smp_message_pass(MSG_ALL_BUT_SELF, MSG_CAPTURE, 0, 1);
 596         }
 597         capture_level++;
 598         restore_flags(flags);
 599 }
 600 
 601 void smp_release(void)
     /*  */
 602 {
 603         unsigned long flags;
 604         int i;
 605 
 606         if(!smp_activated || !smp_commenced)
 607                 return;
 608 #ifdef DEBUG_CAPTURE
 609         printk("R<%d>", smp_processor_id());
 610 #endif
 611         save_flags(flags); cli();
 612         if(!(capture_level - 1)) {
 613                 release = 1;
 614                 for(i = 0; i < smp_num_cpus; i++)
 615                         while(cpu_callin_map[i])
 616                                 barrier();
 617         }
 618         capture_level -= 1;
 619         restore_flags(flags);
 620 }
 621 
 622 /* Park a processor, we must watch for more IPI's to invalidate
 623  * our cache's and TLB's. And also note we can only wait for
 624  * "lock-less" IPI's and process those, as a result of such IPI's
 625  * being non-maskable traps being on is enough to receive them.
 626  */
 627 
 628 /* Message call back. */
 629 void smp_message_irq(void)
     /*  */
 630 {
 631         int i=smp_processor_id();
 632 
 633         switch(smp_msg_id) {
 634         case MSG_CROSS_CALL:
 635                 /* Do it to it. */
 636                 ccall_info.processors_in[i] = 1;
 637                 ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 638                                 ccall_info.arg4, ccall_info.arg5);
 639                 ccall_info.processors_out[i] = 1;
 640                 break;
 641 
 642                 /*
 643                  *      Halt other CPU's for a panic or reboot
 644                  */
 645         case MSG_STOP_CPU:
 646                 sti();
 647                 while(1)
 648                         barrier();
 649 
 650         default:
 651                 printk("CPU #%d sent invalid cross CPU message to CPU #%d: %X(%lX).\n",
 652                        smp_src_cpu,smp_processor_id(),smp_msg_id,smp_msg_data);
 653                 break;
 654         }
 655 }
/* */
root/arch/sparc/kernel/smp.c

DEFINITIONS
