Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 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> |
| 19 | #include <linux/threads.h> |
| 20 | #include <linux/smp.h> |
| 21 | #include <linux/smp_lock.h> |
| 22 | #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. */ |
| 54 | struct cpuinfo_alpha cpu_data[NR_CPUS]; |
| 55 | |
| 56 | /* A collection of single bit ipi messages. */ |
| 57 | static struct { |
| 58 | unsigned long bits ____cacheline_aligned; |
| 59 | } ipi_data[NR_CPUS] __cacheline_aligned; |
| 60 | |
| 61 | enum ipi_message_type { |
| 62 | IPI_RESCHEDULE, |
| 63 | IPI_CALL_FUNC, |
| 64 | IPI_CPU_STOP, |
| 65 | }; |
| 66 | |
| 67 | /* Set to a secondary's cpuid when it comes online. */ |
| 68 | static int smp_secondary_alive __initdata = 0; |
| 69 | |
| 70 | /* Which cpus ids came online. */ |
| 71 | cpumask_t cpu_present_mask; |
| 72 | cpumask_t cpu_online_map; |
| 73 | |
| 74 | EXPORT_SYMBOL(cpu_online_map); |
| 75 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | int smp_num_probed; /* Internal processor count */ |
| 77 | int smp_num_cpus = 1; /* Number that came online. */ |
| 78 | |
| 79 | extern void calibrate_delay(void); |
| 80 | |
| 81 | |
| 82 | |
| 83 | /* |
| 84 | * Called by both boot and secondaries to move global data into |
| 85 | * per-processor storage. |
| 86 | */ |
| 87 | static inline void __init |
| 88 | smp_store_cpu_info(int cpuid) |
| 89 | { |
| 90 | cpu_data[cpuid].loops_per_jiffy = loops_per_jiffy; |
| 91 | cpu_data[cpuid].last_asn = ASN_FIRST_VERSION; |
| 92 | cpu_data[cpuid].need_new_asn = 0; |
| 93 | cpu_data[cpuid].asn_lock = 0; |
| 94 | } |
| 95 | |
| 96 | /* |
| 97 | * Ideally sets up per-cpu profiling hooks. Doesn't do much now... |
| 98 | */ |
| 99 | static inline void __init |
| 100 | smp_setup_percpu_timer(int cpuid) |
| 101 | { |
| 102 | cpu_data[cpuid].prof_counter = 1; |
| 103 | cpu_data[cpuid].prof_multiplier = 1; |
| 104 | } |
| 105 | |
| 106 | static void __init |
| 107 | wait_boot_cpu_to_stop(int cpuid) |
| 108 | { |
| 109 | unsigned long stop = jiffies + 10*HZ; |
| 110 | |
| 111 | while (time_before(jiffies, stop)) { |
| 112 | if (!smp_secondary_alive) |
| 113 | return; |
| 114 | barrier(); |
| 115 | } |
| 116 | |
| 117 | printk("wait_boot_cpu_to_stop: FAILED on CPU %d, hanging now\n", cpuid); |
| 118 | for (;;) |
| 119 | barrier(); |
| 120 | } |
| 121 | |
| 122 | /* |
| 123 | * Where secondaries begin a life of C. |
| 124 | */ |
| 125 | void __init |
| 126 | smp_callin(void) |
| 127 | { |
| 128 | int cpuid = hard_smp_processor_id(); |
| 129 | |
| 130 | if (cpu_test_and_set(cpuid, cpu_online_map)) { |
| 131 | printk("??, cpu 0x%x already present??\n", cpuid); |
| 132 | BUG(); |
| 133 | } |
| 134 | |
| 135 | /* Turn on machine checks. */ |
| 136 | wrmces(7); |
| 137 | |
| 138 | /* Set trap vectors. */ |
| 139 | trap_init(); |
| 140 | |
| 141 | /* Set interrupt vector. */ |
| 142 | wrent(entInt, 0); |
| 143 | |
| 144 | /* Get our local ticker going. */ |
| 145 | smp_setup_percpu_timer(cpuid); |
| 146 | |
| 147 | /* Call platform-specific callin, if specified */ |
| 148 | if (alpha_mv.smp_callin) alpha_mv.smp_callin(); |
| 149 | |
| 150 | /* All kernel threads share the same mm context. */ |
| 151 | atomic_inc(&init_mm.mm_count); |
| 152 | current->active_mm = &init_mm; |
| 153 | |
| 154 | /* Must have completely accurate bogos. */ |
| 155 | local_irq_enable(); |
| 156 | |
| 157 | /* Wait boot CPU to stop with irq enabled before running |
| 158 | calibrate_delay. */ |
| 159 | wait_boot_cpu_to_stop(cpuid); |
| 160 | mb(); |
| 161 | calibrate_delay(); |
| 162 | |
| 163 | smp_store_cpu_info(cpuid); |
| 164 | /* Allow master to continue only after we written loops_per_jiffy. */ |
| 165 | wmb(); |
| 166 | smp_secondary_alive = 1; |
| 167 | |
| 168 | DBGS(("smp_callin: commencing CPU %d current %p active_mm %p\n", |
| 169 | cpuid, current, current->active_mm)); |
| 170 | |
| 171 | /* Do nothing. */ |
| 172 | cpu_idle(); |
| 173 | } |
| 174 | |
| 175 | /* Wait until hwrpb->txrdy is clear for cpu. Return -1 on timeout. */ |
| 176 | static int __init |
| 177 | wait_for_txrdy (unsigned long cpumask) |
| 178 | { |
| 179 | unsigned long timeout; |
| 180 | |
| 181 | if (!(hwrpb->txrdy & cpumask)) |
| 182 | return 0; |
| 183 | |
| 184 | timeout = jiffies + 10*HZ; |
| 185 | while (time_before(jiffies, timeout)) { |
| 186 | if (!(hwrpb->txrdy & cpumask)) |
| 187 | return 0; |
| 188 | udelay(10); |
| 189 | barrier(); |
| 190 | } |
| 191 | |
| 192 | return -1; |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * Send a message to a secondary's console. "START" is one such |
| 197 | * interesting message. ;-) |
| 198 | */ |
| 199 | static void __init |
| 200 | send_secondary_console_msg(char *str, int cpuid) |
| 201 | { |
| 202 | struct percpu_struct *cpu; |
| 203 | register char *cp1, *cp2; |
| 204 | unsigned long cpumask; |
| 205 | size_t len; |
| 206 | |
| 207 | cpu = (struct percpu_struct *) |
| 208 | ((char*)hwrpb |
| 209 | + hwrpb->processor_offset |
| 210 | + cpuid * hwrpb->processor_size); |
| 211 | |
| 212 | cpumask = (1UL << cpuid); |
| 213 | if (wait_for_txrdy(cpumask)) |
| 214 | goto timeout; |
| 215 | |
| 216 | cp2 = str; |
| 217 | len = strlen(cp2); |
| 218 | *(unsigned int *)&cpu->ipc_buffer[0] = len; |
| 219 | cp1 = (char *) &cpu->ipc_buffer[1]; |
| 220 | memcpy(cp1, cp2, len); |
| 221 | |
| 222 | /* atomic test and set */ |
| 223 | wmb(); |
| 224 | set_bit(cpuid, &hwrpb->rxrdy); |
| 225 | |
| 226 | if (wait_for_txrdy(cpumask)) |
| 227 | goto timeout; |
| 228 | return; |
| 229 | |
| 230 | timeout: |
| 231 | printk("Processor %x not ready\n", cpuid); |
| 232 | } |
| 233 | |
| 234 | /* |
| 235 | * A secondary console wants to send a message. Receive it. |
| 236 | */ |
| 237 | static void |
| 238 | recv_secondary_console_msg(void) |
| 239 | { |
| 240 | int mycpu, i, cnt; |
| 241 | unsigned long txrdy = hwrpb->txrdy; |
| 242 | char *cp1, *cp2, buf[80]; |
| 243 | struct percpu_struct *cpu; |
| 244 | |
| 245 | DBGS(("recv_secondary_console_msg: TXRDY 0x%lx.\n", txrdy)); |
| 246 | |
| 247 | mycpu = hard_smp_processor_id(); |
| 248 | |
| 249 | for (i = 0; i < NR_CPUS; i++) { |
| 250 | if (!(txrdy & (1UL << i))) |
| 251 | continue; |
| 252 | |
| 253 | DBGS(("recv_secondary_console_msg: " |
| 254 | "TXRDY contains CPU %d.\n", i)); |
| 255 | |
| 256 | cpu = (struct percpu_struct *) |
| 257 | ((char*)hwrpb |
| 258 | + hwrpb->processor_offset |
| 259 | + i * hwrpb->processor_size); |
| 260 | |
| 261 | DBGS(("recv_secondary_console_msg: on %d from %d" |
| 262 | " HALT_REASON 0x%lx FLAGS 0x%lx\n", |
| 263 | mycpu, i, cpu->halt_reason, cpu->flags)); |
| 264 | |
| 265 | cnt = cpu->ipc_buffer[0] >> 32; |
| 266 | if (cnt <= 0 || cnt >= 80) |
| 267 | strcpy(buf, "<<< BOGUS MSG >>>"); |
| 268 | else { |
| 269 | cp1 = (char *) &cpu->ipc_buffer[11]; |
| 270 | cp2 = buf; |
| 271 | strcpy(cp2, cp1); |
| 272 | |
| 273 | while ((cp2 = strchr(cp2, '\r')) != 0) { |
| 274 | *cp2 = ' '; |
| 275 | if (cp2[1] == '\n') |
| 276 | cp2[1] = ' '; |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | DBGS((KERN_INFO "recv_secondary_console_msg: on %d " |
| 281 | "message is '%s'\n", mycpu, buf)); |
| 282 | } |
| 283 | |
| 284 | hwrpb->txrdy = 0; |
| 285 | } |
| 286 | |
| 287 | /* |
| 288 | * Convince the console to have a secondary cpu begin execution. |
| 289 | */ |
| 290 | static int __init |
| 291 | secondary_cpu_start(int cpuid, struct task_struct *idle) |
| 292 | { |
| 293 | struct percpu_struct *cpu; |
| 294 | struct pcb_struct *hwpcb, *ipcb; |
| 295 | unsigned long timeout; |
| 296 | |
| 297 | cpu = (struct percpu_struct *) |
| 298 | ((char*)hwrpb |
| 299 | + hwrpb->processor_offset |
| 300 | + cpuid * hwrpb->processor_size); |
| 301 | hwpcb = (struct pcb_struct *) cpu->hwpcb; |
Al Viro | 37bfbaf | 2006-01-12 01:05:36 -0800 | [diff] [blame] | 302 | ipcb = &task_thread_info(idle)->pcb; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 303 | |
| 304 | /* Initialize the CPU's HWPCB to something just good enough for |
| 305 | us to get started. Immediately after starting, we'll swpctx |
| 306 | to the target idle task's pcb. Reuse the stack in the mean |
| 307 | time. Precalculate the target PCBB. */ |
| 308 | hwpcb->ksp = (unsigned long)ipcb + sizeof(union thread_union) - 16; |
| 309 | hwpcb->usp = 0; |
| 310 | hwpcb->ptbr = ipcb->ptbr; |
| 311 | hwpcb->pcc = 0; |
| 312 | hwpcb->asn = 0; |
| 313 | hwpcb->unique = virt_to_phys(ipcb); |
| 314 | hwpcb->flags = ipcb->flags; |
| 315 | hwpcb->res1 = hwpcb->res2 = 0; |
| 316 | |
| 317 | #if 0 |
| 318 | DBGS(("KSP 0x%lx PTBR 0x%lx VPTBR 0x%lx UNIQUE 0x%lx\n", |
| 319 | hwpcb->ksp, hwpcb->ptbr, hwrpb->vptb, hwpcb->unique)); |
| 320 | #endif |
| 321 | DBGS(("Starting secondary cpu %d: state 0x%lx pal_flags 0x%lx\n", |
| 322 | cpuid, idle->state, ipcb->flags)); |
| 323 | |
| 324 | /* Setup HWRPB fields that SRM uses to activate secondary CPU */ |
| 325 | hwrpb->CPU_restart = __smp_callin; |
| 326 | hwrpb->CPU_restart_data = (unsigned long) __smp_callin; |
| 327 | |
| 328 | /* Recalculate and update the HWRPB checksum */ |
| 329 | hwrpb_update_checksum(hwrpb); |
| 330 | |
| 331 | /* |
| 332 | * Send a "start" command to the specified processor. |
| 333 | */ |
| 334 | |
| 335 | /* SRM III 3.4.1.3 */ |
| 336 | cpu->flags |= 0x22; /* turn on Context Valid and Restart Capable */ |
| 337 | cpu->flags &= ~1; /* turn off Bootstrap In Progress */ |
| 338 | wmb(); |
| 339 | |
| 340 | send_secondary_console_msg("START\r\n", cpuid); |
| 341 | |
| 342 | /* Wait 10 seconds for an ACK from the console. */ |
| 343 | timeout = jiffies + 10*HZ; |
| 344 | while (time_before(jiffies, timeout)) { |
| 345 | if (cpu->flags & 1) |
| 346 | goto started; |
| 347 | udelay(10); |
| 348 | barrier(); |
| 349 | } |
| 350 | printk(KERN_ERR "SMP: Processor %d failed to start.\n", cpuid); |
| 351 | return -1; |
| 352 | |
| 353 | started: |
| 354 | DBGS(("secondary_cpu_start: SUCCESS for CPU %d!!!\n", cpuid)); |
| 355 | return 0; |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * Bring one cpu online. |
| 360 | */ |
| 361 | static int __init |
| 362 | smp_boot_one_cpu(int cpuid) |
| 363 | { |
| 364 | struct task_struct *idle; |
| 365 | unsigned long timeout; |
| 366 | |
| 367 | /* Cook up an idler for this guy. Note that the address we |
| 368 | give to kernel_thread is irrelevant -- it's going to start |
| 369 | where HWRPB.CPU_restart says to start. But this gets all |
| 370 | the other task-y sort of data structures set up like we |
| 371 | wish. We can't use kernel_thread since we must avoid |
| 372 | rescheduling the child. */ |
| 373 | idle = fork_idle(cpuid); |
| 374 | if (IS_ERR(idle)) |
| 375 | panic("failed fork for CPU %d", cpuid); |
| 376 | |
| 377 | DBGS(("smp_boot_one_cpu: CPU %d state 0x%lx flags 0x%lx\n", |
| 378 | cpuid, idle->state, idle->flags)); |
| 379 | |
| 380 | /* Signal the secondary to wait a moment. */ |
| 381 | smp_secondary_alive = -1; |
| 382 | |
| 383 | /* Whirrr, whirrr, whirrrrrrrrr... */ |
| 384 | if (secondary_cpu_start(cpuid, idle)) |
| 385 | return -1; |
| 386 | |
| 387 | /* Notify the secondary CPU it can run calibrate_delay. */ |
| 388 | mb(); |
| 389 | smp_secondary_alive = 0; |
| 390 | |
| 391 | /* We've been acked by the console; wait one second for |
| 392 | the task to start up for real. */ |
| 393 | timeout = jiffies + 1*HZ; |
| 394 | while (time_before(jiffies, timeout)) { |
| 395 | if (smp_secondary_alive == 1) |
| 396 | goto alive; |
| 397 | udelay(10); |
| 398 | barrier(); |
| 399 | } |
| 400 | |
| 401 | /* We failed to boot the CPU. */ |
| 402 | |
| 403 | printk(KERN_ERR "SMP: Processor %d is stuck.\n", cpuid); |
| 404 | return -1; |
| 405 | |
| 406 | alive: |
| 407 | /* Another "Red Snapper". */ |
| 408 | return 0; |
| 409 | } |
| 410 | |
| 411 | /* |
| 412 | * Called from setup_arch. Detect an SMP system and which processors |
| 413 | * are present. |
| 414 | */ |
| 415 | void __init |
| 416 | setup_smp(void) |
| 417 | { |
| 418 | struct percpu_struct *cpubase, *cpu; |
| 419 | unsigned long i; |
| 420 | |
| 421 | if (boot_cpuid != 0) { |
| 422 | printk(KERN_WARNING "SMP: Booting off cpu %d instead of 0?\n", |
| 423 | boot_cpuid); |
| 424 | } |
| 425 | |
| 426 | if (hwrpb->nr_processors > 1) { |
| 427 | int boot_cpu_palrev; |
| 428 | |
| 429 | DBGS(("setup_smp: nr_processors %ld\n", |
| 430 | hwrpb->nr_processors)); |
| 431 | |
| 432 | cpubase = (struct percpu_struct *) |
| 433 | ((char*)hwrpb + hwrpb->processor_offset); |
| 434 | boot_cpu_palrev = cpubase->pal_revision; |
| 435 | |
| 436 | for (i = 0; i < hwrpb->nr_processors; i++) { |
| 437 | cpu = (struct percpu_struct *) |
| 438 | ((char *)cpubase + i*hwrpb->processor_size); |
| 439 | if ((cpu->flags & 0x1cc) == 0x1cc) { |
| 440 | smp_num_probed++; |
| 441 | /* Assume here that "whami" == index */ |
Ivan Kokshaysky | 328c2a8 | 2006-02-08 11:55:06 +0300 | [diff] [blame^] | 442 | cpu_set(i, cpu_possible_map); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 443 | 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; |
Ivan Kokshaysky | 328c2a8 | 2006-02-08 11:55:06 +0300 | [diff] [blame^] | 453 | cpu_set(boot_cpuid, cpu_possible_map); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | } |
| 455 | cpu_present_mask = cpumask_of_cpu(boot_cpuid); |
| 456 | |
| 457 | printk(KERN_INFO "SMP: %d CPUs probed -- cpu_present_mask = %lx\n", |
Ivan Kokshaysky | 328c2a8 | 2006-02-08 11:55:06 +0300 | [diff] [blame^] | 458 | smp_num_probed, cpu_possible_map.bits[0]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | } |
| 460 | |
| 461 | /* |
| 462 | * Called by smp_init prepare the secondaries |
| 463 | */ |
| 464 | void __init |
| 465 | smp_prepare_cpus(unsigned int max_cpus) |
| 466 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | /* Take care of some initial bookkeeping. */ |
| 468 | memset(ipi_data, 0, sizeof(ipi_data)); |
| 469 | |
| 470 | current_thread_info()->cpu = boot_cpuid; |
| 471 | |
| 472 | smp_store_cpu_info(boot_cpuid); |
| 473 | smp_setup_percpu_timer(boot_cpuid); |
| 474 | |
| 475 | /* Nothing to do on a UP box, or when told not to. */ |
| 476 | if (smp_num_probed == 1 || max_cpus == 0) { |
| 477 | cpu_present_mask = cpumask_of_cpu(boot_cpuid); |
| 478 | printk(KERN_INFO "SMP mode deactivated.\n"); |
| 479 | return; |
| 480 | } |
| 481 | |
| 482 | printk(KERN_INFO "SMP starting up secondaries.\n"); |
| 483 | |
Ivan Kokshaysky | 328c2a8 | 2006-02-08 11:55:06 +0300 | [diff] [blame^] | 484 | smp_num_cpus = smp_num_probed; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | } |
| 486 | |
| 487 | void __devinit |
| 488 | smp_prepare_boot_cpu(void) |
| 489 | { |
| 490 | /* |
| 491 | * Mark the boot cpu (current cpu) as both present and online |
| 492 | */ |
| 493 | cpu_set(smp_processor_id(), cpu_present_mask); |
| 494 | cpu_set(smp_processor_id(), cpu_online_map); |
| 495 | } |
| 496 | |
| 497 | int __devinit |
| 498 | __cpu_up(unsigned int cpu) |
| 499 | { |
| 500 | smp_boot_one_cpu(cpu); |
| 501 | |
| 502 | return cpu_online(cpu) ? 0 : -ENOSYS; |
| 503 | } |
| 504 | |
| 505 | void __init |
| 506 | smp_cpus_done(unsigned int max_cpus) |
| 507 | { |
| 508 | int cpu; |
| 509 | unsigned long bogosum = 0; |
| 510 | |
| 511 | for(cpu = 0; cpu < NR_CPUS; cpu++) |
| 512 | if (cpu_online(cpu)) |
| 513 | bogosum += cpu_data[cpu].loops_per_jiffy; |
| 514 | |
| 515 | printk(KERN_INFO "SMP: Total of %d processors activated " |
| 516 | "(%lu.%02lu BogoMIPS).\n", |
| 517 | num_online_cpus(), |
| 518 | (bogosum + 2500) / (500000/HZ), |
| 519 | ((bogosum + 2500) / (5000/HZ)) % 100); |
| 520 | } |
| 521 | |
| 522 | |
| 523 | void |
| 524 | smp_percpu_timer_interrupt(struct pt_regs *regs) |
| 525 | { |
| 526 | int cpu = smp_processor_id(); |
| 527 | unsigned long user = user_mode(regs); |
| 528 | struct cpuinfo_alpha *data = &cpu_data[cpu]; |
| 529 | |
| 530 | /* Record kernel PC. */ |
| 531 | profile_tick(CPU_PROFILING, regs); |
| 532 | |
| 533 | if (!--data->prof_counter) { |
| 534 | /* We need to make like a normal interrupt -- otherwise |
| 535 | timer interrupts ignore the global interrupt lock, |
| 536 | which would be a Bad Thing. */ |
| 537 | irq_enter(); |
| 538 | |
| 539 | update_process_times(user); |
| 540 | |
| 541 | data->prof_counter = data->prof_multiplier; |
| 542 | |
| 543 | irq_exit(); |
| 544 | } |
| 545 | } |
| 546 | |
| 547 | int __init |
| 548 | setup_profiling_timer(unsigned int multiplier) |
| 549 | { |
| 550 | return -EINVAL; |
| 551 | } |
| 552 | |
| 553 | |
| 554 | static void |
| 555 | send_ipi_message(cpumask_t to_whom, enum ipi_message_type operation) |
| 556 | { |
| 557 | int i; |
| 558 | |
| 559 | mb(); |
| 560 | for_each_cpu_mask(i, to_whom) |
| 561 | set_bit(operation, &ipi_data[i].bits); |
| 562 | |
| 563 | mb(); |
| 564 | for_each_cpu_mask(i, to_whom) |
| 565 | wripir(i); |
| 566 | } |
| 567 | |
| 568 | /* Structure and data for smp_call_function. This is designed to |
| 569 | minimize static memory requirements. Plus it looks cleaner. */ |
| 570 | |
| 571 | struct smp_call_struct { |
| 572 | void (*func) (void *info); |
| 573 | void *info; |
| 574 | long wait; |
| 575 | atomic_t unstarted_count; |
| 576 | atomic_t unfinished_count; |
| 577 | }; |
| 578 | |
| 579 | static struct smp_call_struct *smp_call_function_data; |
| 580 | |
| 581 | /* Atomicly drop data into a shared pointer. The pointer is free if |
| 582 | it is initially locked. If retry, spin until free. */ |
| 583 | |
| 584 | static int |
| 585 | pointer_lock (void *lock, void *data, int retry) |
| 586 | { |
| 587 | void *old, *tmp; |
| 588 | |
| 589 | mb(); |
| 590 | again: |
| 591 | /* Compare and swap with zero. */ |
| 592 | asm volatile ( |
| 593 | "1: ldq_l %0,%1\n" |
| 594 | " mov %3,%2\n" |
| 595 | " bne %0,2f\n" |
| 596 | " stq_c %2,%1\n" |
| 597 | " beq %2,1b\n" |
| 598 | "2:" |
| 599 | : "=&r"(old), "=m"(*(void **)lock), "=&r"(tmp) |
| 600 | : "r"(data) |
| 601 | : "memory"); |
| 602 | |
| 603 | if (old == 0) |
| 604 | return 0; |
| 605 | if (! retry) |
| 606 | return -EBUSY; |
| 607 | |
| 608 | while (*(void **)lock) |
| 609 | barrier(); |
| 610 | goto again; |
| 611 | } |
| 612 | |
| 613 | void |
| 614 | handle_ipi(struct pt_regs *regs) |
| 615 | { |
| 616 | int this_cpu = smp_processor_id(); |
| 617 | unsigned long *pending_ipis = &ipi_data[this_cpu].bits; |
| 618 | unsigned long ops; |
| 619 | |
| 620 | #if 0 |
| 621 | DBGS(("handle_ipi: on CPU %d ops 0x%lx PC 0x%lx\n", |
| 622 | this_cpu, *pending_ipis, regs->pc)); |
| 623 | #endif |
| 624 | |
| 625 | mb(); /* Order interrupt and bit testing. */ |
| 626 | while ((ops = xchg(pending_ipis, 0)) != 0) { |
| 627 | mb(); /* Order bit clearing and data access. */ |
| 628 | do { |
| 629 | unsigned long which; |
| 630 | |
| 631 | which = ops & -ops; |
| 632 | ops &= ~which; |
| 633 | which = __ffs(which); |
| 634 | |
| 635 | switch (which) { |
| 636 | case IPI_RESCHEDULE: |
| 637 | /* Reschedule callback. Everything to be done |
| 638 | is done by the interrupt return path. */ |
| 639 | break; |
| 640 | |
| 641 | case IPI_CALL_FUNC: |
| 642 | { |
| 643 | struct smp_call_struct *data; |
| 644 | void (*func)(void *info); |
| 645 | void *info; |
| 646 | int wait; |
| 647 | |
| 648 | data = smp_call_function_data; |
| 649 | func = data->func; |
| 650 | info = data->info; |
| 651 | wait = data->wait; |
| 652 | |
| 653 | /* Notify the sending CPU that the data has been |
| 654 | received, and execution is about to begin. */ |
| 655 | mb(); |
| 656 | atomic_dec (&data->unstarted_count); |
| 657 | |
| 658 | /* At this point the structure may be gone unless |
| 659 | wait is true. */ |
| 660 | (*func)(info); |
| 661 | |
| 662 | /* Notify the sending CPU that the task is done. */ |
| 663 | mb(); |
| 664 | if (wait) atomic_dec (&data->unfinished_count); |
| 665 | break; |
| 666 | } |
| 667 | |
| 668 | case IPI_CPU_STOP: |
| 669 | halt(); |
| 670 | |
| 671 | default: |
| 672 | printk(KERN_CRIT "Unknown IPI on CPU %d: %lu\n", |
| 673 | this_cpu, which); |
| 674 | break; |
| 675 | } |
| 676 | } while (ops); |
| 677 | |
| 678 | mb(); /* Order data access and bit testing. */ |
| 679 | } |
| 680 | |
| 681 | cpu_data[this_cpu].ipi_count++; |
| 682 | |
| 683 | if (hwrpb->txrdy) |
| 684 | recv_secondary_console_msg(); |
| 685 | } |
| 686 | |
| 687 | void |
| 688 | smp_send_reschedule(int cpu) |
| 689 | { |
| 690 | #ifdef DEBUG_IPI_MSG |
| 691 | if (cpu == hard_smp_processor_id()) |
| 692 | printk(KERN_WARNING |
| 693 | "smp_send_reschedule: Sending IPI to self.\n"); |
| 694 | #endif |
| 695 | send_ipi_message(cpumask_of_cpu(cpu), IPI_RESCHEDULE); |
| 696 | } |
| 697 | |
| 698 | void |
| 699 | smp_send_stop(void) |
| 700 | { |
| 701 | cpumask_t to_whom = cpu_possible_map; |
| 702 | cpu_clear(smp_processor_id(), to_whom); |
| 703 | #ifdef DEBUG_IPI_MSG |
| 704 | if (hard_smp_processor_id() != boot_cpu_id) |
| 705 | printk(KERN_WARNING "smp_send_stop: Not on boot cpu.\n"); |
| 706 | #endif |
| 707 | send_ipi_message(to_whom, IPI_CPU_STOP); |
| 708 | } |
| 709 | |
| 710 | /* |
| 711 | * Run a function on all other CPUs. |
| 712 | * <func> The function to run. This must be fast and non-blocking. |
| 713 | * <info> An arbitrary pointer to pass to the function. |
| 714 | * <retry> If true, keep retrying until ready. |
| 715 | * <wait> If true, wait until function has completed on other CPUs. |
| 716 | * [RETURNS] 0 on success, else a negative status code. |
| 717 | * |
| 718 | * Does not return until remote CPUs are nearly ready to execute <func> |
| 719 | * or are or have executed. |
| 720 | * You must not call this function with disabled interrupts or from a |
| 721 | * hardware interrupt handler or from a bottom half handler. |
| 722 | */ |
| 723 | |
| 724 | int |
| 725 | smp_call_function_on_cpu (void (*func) (void *info), void *info, int retry, |
| 726 | int wait, cpumask_t to_whom) |
| 727 | { |
| 728 | struct smp_call_struct data; |
| 729 | unsigned long timeout; |
| 730 | int num_cpus_to_call; |
| 731 | |
| 732 | /* Can deadlock when called with interrupts disabled */ |
| 733 | WARN_ON(irqs_disabled()); |
| 734 | |
| 735 | data.func = func; |
| 736 | data.info = info; |
| 737 | data.wait = wait; |
| 738 | |
| 739 | cpu_clear(smp_processor_id(), to_whom); |
| 740 | num_cpus_to_call = cpus_weight(to_whom); |
| 741 | |
| 742 | atomic_set(&data.unstarted_count, num_cpus_to_call); |
| 743 | atomic_set(&data.unfinished_count, num_cpus_to_call); |
| 744 | |
| 745 | /* Acquire the smp_call_function_data mutex. */ |
| 746 | if (pointer_lock(&smp_call_function_data, &data, retry)) |
| 747 | return -EBUSY; |
| 748 | |
| 749 | /* Send a message to the requested CPUs. */ |
| 750 | send_ipi_message(to_whom, IPI_CALL_FUNC); |
| 751 | |
| 752 | /* Wait for a minimal response. */ |
| 753 | timeout = jiffies + HZ; |
| 754 | while (atomic_read (&data.unstarted_count) > 0 |
| 755 | && time_before (jiffies, timeout)) |
| 756 | barrier(); |
| 757 | |
| 758 | /* If there's no response yet, log a message but allow a longer |
| 759 | * timeout period -- if we get a response this time, log |
| 760 | * a message saying when we got it.. |
| 761 | */ |
| 762 | if (atomic_read(&data.unstarted_count) > 0) { |
| 763 | long start_time = jiffies; |
| 764 | printk(KERN_ERR "%s: initial timeout -- trying long wait\n", |
| 765 | __FUNCTION__); |
| 766 | timeout = jiffies + 30 * HZ; |
| 767 | while (atomic_read(&data.unstarted_count) > 0 |
| 768 | && time_before(jiffies, timeout)) |
| 769 | barrier(); |
| 770 | if (atomic_read(&data.unstarted_count) <= 0) { |
| 771 | long delta = jiffies - start_time; |
| 772 | printk(KERN_ERR |
| 773 | "%s: response %ld.%ld seconds into long wait\n", |
| 774 | __FUNCTION__, delta / HZ, |
| 775 | (100 * (delta - ((delta / HZ) * HZ))) / HZ); |
| 776 | } |
| 777 | } |
| 778 | |
| 779 | /* We either got one or timed out -- clear the lock. */ |
| 780 | mb(); |
| 781 | smp_call_function_data = NULL; |
| 782 | |
| 783 | /* |
| 784 | * If after both the initial and long timeout periods we still don't |
| 785 | * have a response, something is very wrong... |
| 786 | */ |
| 787 | BUG_ON(atomic_read (&data.unstarted_count) > 0); |
| 788 | |
| 789 | /* Wait for a complete response, if needed. */ |
| 790 | if (wait) { |
| 791 | while (atomic_read (&data.unfinished_count) > 0) |
| 792 | barrier(); |
| 793 | } |
| 794 | |
| 795 | return 0; |
| 796 | } |
| 797 | |
| 798 | int |
| 799 | smp_call_function (void (*func) (void *info), void *info, int retry, int wait) |
| 800 | { |
| 801 | return smp_call_function_on_cpu (func, info, retry, wait, |
| 802 | cpu_online_map); |
| 803 | } |
| 804 | |
| 805 | static void |
| 806 | ipi_imb(void *ignored) |
| 807 | { |
| 808 | imb(); |
| 809 | } |
| 810 | |
| 811 | void |
| 812 | smp_imb(void) |
| 813 | { |
| 814 | /* Must wait other processors to flush their icache before continue. */ |
| 815 | if (on_each_cpu(ipi_imb, NULL, 1, 1)) |
| 816 | printk(KERN_CRIT "smp_imb: timed out\n"); |
| 817 | } |
| 818 | |
| 819 | static void |
| 820 | ipi_flush_tlb_all(void *ignored) |
| 821 | { |
| 822 | tbia(); |
| 823 | } |
| 824 | |
| 825 | void |
| 826 | flush_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 | |
| 837 | static void |
| 838 | ipi_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 | |
| 847 | void |
| 848 | flush_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 | } |
| 873 | |
| 874 | struct flush_tlb_page_struct { |
| 875 | struct vm_area_struct *vma; |
| 876 | struct mm_struct *mm; |
| 877 | unsigned long addr; |
| 878 | }; |
| 879 | |
| 880 | static void |
| 881 | ipi_flush_tlb_page(void *x) |
| 882 | { |
| 883 | struct flush_tlb_page_struct *data = (struct flush_tlb_page_struct *)x; |
| 884 | struct mm_struct * mm = data->mm; |
| 885 | |
| 886 | if (mm == current->active_mm && !asn_locked()) |
| 887 | flush_tlb_current_page(mm, data->vma, data->addr); |
| 888 | else |
| 889 | flush_tlb_other(mm); |
| 890 | } |
| 891 | |
| 892 | void |
| 893 | flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) |
| 894 | { |
| 895 | struct flush_tlb_page_struct data; |
| 896 | struct mm_struct *mm = vma->vm_mm; |
| 897 | |
| 898 | preempt_disable(); |
| 899 | |
| 900 | if (mm == current->active_mm) { |
| 901 | flush_tlb_current_page(mm, vma, addr); |
| 902 | if (atomic_read(&mm->mm_users) <= 1) { |
| 903 | int cpu, this_cpu = smp_processor_id(); |
| 904 | for (cpu = 0; cpu < NR_CPUS; cpu++) { |
| 905 | if (!cpu_online(cpu) || cpu == this_cpu) |
| 906 | continue; |
| 907 | if (mm->context[cpu]) |
| 908 | mm->context[cpu] = 0; |
| 909 | } |
| 910 | preempt_enable(); |
| 911 | return; |
| 912 | } |
| 913 | } |
| 914 | |
| 915 | data.vma = vma; |
| 916 | data.mm = mm; |
| 917 | data.addr = addr; |
| 918 | |
| 919 | if (smp_call_function(ipi_flush_tlb_page, &data, 1, 1)) { |
| 920 | printk(KERN_CRIT "flush_tlb_page: timed out\n"); |
| 921 | } |
| 922 | |
| 923 | preempt_enable(); |
| 924 | } |
| 925 | |
| 926 | void |
| 927 | flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) |
| 928 | { |
| 929 | /* On the Alpha we always flush the whole user tlb. */ |
| 930 | flush_tlb_mm(vma->vm_mm); |
| 931 | } |
| 932 | |
| 933 | static void |
| 934 | ipi_flush_icache_page(void *x) |
| 935 | { |
| 936 | struct mm_struct *mm = (struct mm_struct *) x; |
| 937 | if (mm == current->active_mm && !asn_locked()) |
| 938 | __load_new_mm_context(mm); |
| 939 | else |
| 940 | flush_tlb_other(mm); |
| 941 | } |
| 942 | |
| 943 | void |
| 944 | flush_icache_user_range(struct vm_area_struct *vma, struct page *page, |
| 945 | unsigned long addr, int len) |
| 946 | { |
| 947 | struct mm_struct *mm = vma->vm_mm; |
| 948 | |
| 949 | if ((vma->vm_flags & VM_EXEC) == 0) |
| 950 | return; |
| 951 | |
| 952 | preempt_disable(); |
| 953 | |
| 954 | if (mm == current->active_mm) { |
| 955 | __load_new_mm_context(mm); |
| 956 | if (atomic_read(&mm->mm_users) <= 1) { |
| 957 | int cpu, this_cpu = smp_processor_id(); |
| 958 | for (cpu = 0; cpu < NR_CPUS; cpu++) { |
| 959 | if (!cpu_online(cpu) || cpu == this_cpu) |
| 960 | continue; |
| 961 | if (mm->context[cpu]) |
| 962 | mm->context[cpu] = 0; |
| 963 | } |
| 964 | preempt_enable(); |
| 965 | return; |
| 966 | } |
| 967 | } |
| 968 | |
| 969 | if (smp_call_function(ipi_flush_icache_page, mm, 1, 1)) { |
| 970 | printk(KERN_CRIT "flush_icache_page: timed out\n"); |
| 971 | } |
| 972 | |
| 973 | preempt_enable(); |
| 974 | } |