sys/platform/vkernel/i386/mp.c

   1 /*
   2  * Copyright (c) 2007 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/platform/vkernel/i386/mp.c,v 1.1 2007/06/18 18:57:12 josepht Exp $
  35  */
  36
  37
  38 #include <sys/interrupt.h>
  39 #include <sys/kernel.h>
  40 #include <sys/memrange.h>
  41 #include <sys/tls.h>
  42 #include <sys/types.h>
  43
  44 #include <vm/vm_extern.h>
  45 #include <vm/vm_kern.h>
  46 #include <vm/vm_object.h>
  47 #include <vm/vm_page.h>
  48
  49 #include <machine/cpufunc.h>
  50 #include <machine/globaldata.h>
  51 #include <machine/md_var.h>
  52 #include <machine/pmap.h>
  53 #include <machine/smp.h>
  54 #include <machine/tls.h>
  55
  56 #include <unistd.h>
  57 #include <pthread.h>
  58 #include <signal.h>
  59 #include <stdio.h>
  60
  61 extern pt_entry_t *KPTphys;
  62
  63 volatile u_int  stopped_cpus;
  64 cpumask_t       smp_active_mask = 0;  /* which cpus are ready for IPIs etc? */
  65 static int      boot_address;
  66 static cpumask_t smp_startup_mask = 1;  /* which cpus have been started */
  67 int             mp_naps;                /* # of Applications processors */
  68 static int  mp_finish;
  69
  70 /* function prototypes XXX these should go elsewhere */
  71 void bootstrap_idle(void);
  72 void single_cpu_ipi(int, int, int);
  73 void selected_cpu_ipi(u_int, int, int);
  74 #if 0
  75 void ipi_handler(int);
  76 #endif
  77
  78 pt_entry_t *SMPpt;
  79
  80 /* AP uses this during bootstrap.  Do not staticize.  */
  81 char *bootSTK;
  82 static int bootAP;
  83
  84
  85 /* XXX these need to go into the appropriate header file */
  86 static int start_all_aps(u_int);
  87 void init_secondary(void);
  88 void *start_ap(void *);
  89
  90 /*
  91  * Get SMP fully working before we start initializing devices.
  92  */
  93 static
  94 void
  95 ap_finish(void)
  96 {
  97         int i;
  98         cpumask_t ncpus_mask = 0;
  99
 100         for (i = 1; i <= ncpus; i++)
 101                 ncpus_mask |= (1 << i);
 102
 103         mp_finish = 1;
 104         if (bootverbose)
 105                 kprintf("Finish MP startup\n");
 106
 107         rel_mplock();
 108
 109         while (smp_active_mask != smp_startup_mask)
 110                 cpu_lfence();
 111
 112         while (try_mplock() == 0)
 113                 ;
 114         if (bootverbose)
 115                 kprintf("Active CPU Mask: %08x\n", smp_active_mask);
 116 }
 117
 118 SYSINIT(finishsmp, SI_BOOT2_FINISH_SMP, SI_ORDER_FIRST, ap_finish, NULL)
 119
 120
 121 void *
 122 start_ap(void *arg)
 123 {
 124         init_secondary();
 125
 126         bootstrap_idle();
 127
 128         return(NULL); /* NOTREACHED */
 129 }
 130
 131 /* storage for AP thread IDs */
 132 pthread_t ap_tids[MAXCPU];
 133
 134 void
 135 mp_start(void)
 136 {
 137         int shift;
 138
 139         /* XXX testing 2 cpus */
 140         ncpus = 2;
 141
 142         mp_naps = ncpus - 1;
 143
 144         /* ncpus2 -- ncpus rounded down to the nearest power of 2 */
 145         for (shift = 0; (1 << shift) <= ncpus; ++shift)
 146                 ;
 147         --shift;
 148         ncpus2_shift = shift;
 149         ncpus2 = 1 << shift;
 150         ncpus2_mask = ncpus2 - 1;
 151
 152         /* ncpus_fit -- ncpus rounded up to the nearest power of 2 */
 153         if ((1 << shift) < ncpus)
 154                 ++shift;
 155         ncpus_fit = 1 << shift;
 156         ncpus_fit_mask = ncpus_fit - 1;
 157
 158         start_all_aps(boot_address);
 159
 160 }
 161
 162 void
 163 mp_announce(void)
 164 {
 165         int x;
 166
 167         kprintf("DragonFly/MP: Multiprocessor\n");
 168         kprintf(" cpu0 (BSP)\n");
 169
 170         for (x = 1; x <= mp_naps; ++x)
 171                 kprintf(" cpu%d (AP)\n", x);
 172 }
 173
 174 void
 175 forward_fastint_remote(void *arg)
 176 {
 177         panic("XXX forward_fastint_remote()");
 178 }
 179
 180 void
 181 cpu_send_ipiq(int dcpu)
 182 {
 183         kprintf("cpu_send_ipiq(%d), smp_active_mask = %x\n", dcpu, smp_active_mask);
 184         if ((1 << dcpu) & smp_active_mask)
 185                 if (pthread_kill(ap_tids[dcpu], SIGUSR1) != 0)
 186                         panic("pthread_kill failed in cpu_send_ipiq");
 187 #if 0
 188         panic("XXX cpu_send_ipiq()");
 189 #endif
 190 }
 191
 192 void
 193 smp_invltlb(void)
 194 {
 195 }
 196
 197 void
 198 single_cpu_ipi(int cpu, int vector, int delivery_mode)
 199 {
 200         kprintf("XXX single_cpu_ipi\n");
 201 }
 202
 203 void
 204 selected_cpu_ipi(u_int target, int vector, int delivery_mode)
 205 {
 206         crit_enter();
 207         while (target) {
 208                 int n = bsfl(target);
 209                 target &= ~(1 << n);
 210                 single_cpu_ipi(n, vector, delivery_mode);
 211         }
 212         crit_exit();
 213 }
 214
 215 int
 216 stop_cpus(u_int map)
 217 {
 218         map &= smp_active_mask;
 219
 220         crit_enter();
 221         while (map) {
 222                 int n = bsfl(map);
 223                 map &= ~(1 << n);
 224                 if (pthread_kill(ap_tids[n], SIGSTOP) != 0)
 225                         panic("stop_cpus: pthread_kill failed");
 226         }
 227         crit_exit();
 228 #if 0
 229         panic("XXX stop_cpus()");
 230 #endif
 231
 232         return(1);
 233 }
 234
 235 int
 236 restart_cpus(u_int map)
 237 {
 238         map &= smp_active_mask;
 239
 240         crit_enter();
 241         while (map) {
 242                 int n = bsfl(map);
 243                 map &= ~(1 << n);
 244                 if (pthread_kill(ap_tids[n], SIGCONT) != 0)
 245                         panic("restart_cpus: pthread_kill failed");
 246         }
 247         crit_exit();
 248 #if 0
 249         panic("XXX restart_cpus()");
 250 #endif
 251
 252         return(1);
 253 }
 254
 255 void
 256 ap_init(void)
 257 {
 258         /*
 259          * Adjust smp_startup_mask to signal the BSP that we have started
 260          * up successfully.  Note that we do not yet hold the BGL.  The BSP
 261          * is waiting for our signal.
 262          *
 263          * We can't set our bit in smp_active_mask yet because we are holding
 264          * interrupts physically disabled and remote cpus could deadlock
 265          * trying to send us an IPI.
 266          */
 267
 268         smp_startup_mask |= 1 << mycpu->gd_cpuid;
 269         cpu_mfence();
 270
 271         /*
 272          * Interlock for finalization.  Wait until mp_finish is non-zero,
 273          * then get the MP lock.
 274          *
 275          * Note: We are in a critical section.
 276          *
 277          * Note: We have to synchronize td_mpcount to our desired MP state
 278          * before calling cpu_try_mplock().
 279          *
 280          * Note: we are the idle thread, we can only spin.
 281          *
 282          * Note: The load fence is memory volatile and prevents the compiler
 283          * from improperly caching mp_finish, and the cpu from improperly
 284          * caching it.
 285          */
 286
 287         while (mp_finish == 0) {
 288                 cpu_lfence();
 289         }
 290         ++curthread->td_mpcount;
 291         while (cpu_try_mplock() == 0)
 292             ;
 293
 294         /* BSP may have changed PTD while we're waiting for the lock */
 295         cpu_invltlb();
 296
 297         /* Build our map of 'other' CPUs. */
 298         mycpu->gd_other_cpus = smp_startup_mask & ~(1 << mycpu->gd_cpuid);
 299
 300         kprintf("SMP: AP CPU #%d Launched!\n", mycpu->gd_cpuid);
 301
 302
 303         /* Set memory range attributes for this CPU to match the BSP */
 304         mem_range_AP_init();
 305         /*
 306          * Once we go active we must process any IPIQ messages that may
 307          * have been queued, because no actual IPI will occur until we
 308          * set our bit in the smp_active_mask.  If we don't the IPI
 309          * message interlock could be left set which would also prevent
 310          * further IPIs.
 311          *
 312          * The idle loop doesn't expect the BGL to be held and while
 313          * lwkt_switch() normally cleans things up this is a special case
 314          * because we returning almost directly into the idle loop.
 315          *
 316          * The idle thread is never placed on the runq, make sure
 317          * nothing we've done put it there.
 318          */
 319         KKASSERT(curthread->td_mpcount == 1);
 320         smp_active_mask |= 1 << mycpu->gd_cpuid;
 321
 322         mdcpu->gd_fpending = 0;
 323         mdcpu->gd_ipending = 0;
 324         initclocks_pcpu();      /* clock interrupts (via IPIs) */
 325         lwkt_process_ipiq();
 326
 327         /*
 328          * Releasing the mp lock lets the BSP finish up the SMP init
 329          */
 330         rel_mplock();
 331         KKASSERT((curthread->td_flags & TDF_RUNQ) == 0);
 332 }
 333
 334 void
 335 init_secondary(void)
 336 {
 337         int     myid = bootAP;
 338         struct mdglobaldata *md;
 339         struct privatespace *ps;
 340
 341         ps = &CPU_prvspace[myid];
 342
 343         ps->mdglobaldata.mi.gd_prvspace = ps;
 344
 345         /*
 346          * Setup the %gs for cpu #n.  The mycpu macro works after this
 347          * point.
 348          */
 349         tls_set_fs(&CPU_prvspace[myid], sizeof(struct privatespace));
 350
 351         md = mdcpu;     /* loaded through %fs:0 (mdglobaldata.mi.gd_prvspace)*/
 352
 353         md->gd_common_tss.tss_esp0 = 0; /* not used until after switch */
 354         md->gd_common_tss.tss_ss0 = GSEL(GDATA_SEL, SEL_KPL);
 355         md->gd_common_tss.tss_ioopt = (sizeof md->gd_common_tss) << 16;
 356
 357         /*
 358          * Set to a known state:
 359          * Set by mpboot.s: CR0_PG, CR0_PE
 360          * Set by cpu_setregs: CR0_NE, CR0_MP, CR0_TS, CR0_WP, CR0_AM
 361          */
 362 }
 363
 364 static int
 365 start_all_aps(u_int boot_addr)
 366 {
 367         int x, i;
 368         int *arg;
 369         struct mdglobaldata *gd;
 370         struct privatespace *ps;
 371         vm_page_t m;
 372         vm_offset_t va;
 373 #if 0
 374         struct lwp_params params;
 375 #endif
 376
 377 #if 0
 378         /* store the mappings so we can populate gd_CMAP[0-2] and gd_PMAP3  */
 379         vpte_t *SMPpt2[4];
 380 #endif
 381
 382         /*
 383          * needed for ipis to initial thread
 384          * FIXME: rename ap_tids?
 385          */
 386         ap_tids[0] = pthread_self();
 387
 388         for (x = 1; x <= mp_naps; x++)
 389         {
 390                 /* Allocate space for the CPU's private space. */
 391                 va = (vm_offset_t)&CPU_prvspace[x];
 392                 for (i = 0; i < sizeof(struct mdglobaldata); i += PAGE_SIZE) {
 393                         va =(vm_offset_t)&CPU_prvspace[x].mdglobaldata + i;
 394                         m = vm_page_alloc(&kernel_object, va, VM_ALLOC_SYSTEM);
 395                         pmap_kenter_quick(va, m->phys_addr);
 396 #if 0
 397                         KKASSERT(i < 4);
 398                         SMPpt2[i] = pmap_kpte(va);
 399 #endif
 400                 }
 401
 402                 for (i = 0; i < sizeof(CPU_prvspace[x].idlestack); i += PAGE_SIZE) {
 403                         va =(vm_offset_t)&CPU_prvspace[x].idlestack + i;
 404                         m = vm_page_alloc(&kernel_object, va, VM_ALLOC_SYSTEM);
 405                         pmap_kenter_quick(va, m->phys_addr);
 406                 }
 407
 408                 gd = &CPU_prvspace[x].mdglobaldata;     /* official location */
 409                 bzero(gd, sizeof(*gd));
 410                 gd->mi.gd_prvspace = ps = &CPU_prvspace[x];
 411
 412                 /* prime data page for it to use */
 413                 mi_gdinit(&gd->mi, x);
 414                 cpu_gdinit(gd, x);
 415
 416 #if 0
 417                 gd->gd_CMAP1 = SMPpt2[0];
 418                 gd->gd_CMAP2 = SMPpt2[1];
 419                 gd->gd_CMAP3 = SMPpt2[2];
 420                 gd->gd_PMAP1 = SMPpt2[3];
 421                 gd->gd_CADDR1 = ps->CPAGE1;
 422                 gd->gd_CADDR2 = ps->CPAGE2;
 423                 gd->gd_CADDR3 = ps->CPAGE3;
 424                 gd->gd_PADDR1 = (unsigned *)ps->PPAGE1;
 425 #endif
 426                 gd->mi.gd_ipiq = (void *)kmem_alloc(&kernel_map, sizeof(lwkt_ipiq) * (mp_naps + 1));
 427                 bzero(gd->mi.gd_ipiq, sizeof(lwkt_ipiq) * (mp_naps + 1));
 428
 429                 /*
 430                  * Setup the AP boot stack
 431                  */
 432                 bootSTK = &ps->idlestack[UPAGES*PAGE_SIZE/2];
 433                 bootAP = x;
 434
 435                 /* build our map of 'other' CPUs */
 436                 mycpu->gd_other_cpus = smp_startup_mask &
 437                         ~(1 << mycpu->gd_cpuid);
 438                 mycpu->gd_ipiq = (void *)kmem_alloc(&kernel_map,
 439                         sizeof(lwkt_ipiq) * ncpus);
 440
 441                 bzero(mycpu->gd_ipiq, sizeof(lwkt_ipiq) * ncpus);
 442
 443                 /*
 444                  * Setup the AP's lwp, this is the 'cpu'
 445                  */
 446                 arg = (int *)kmem_alloc(&kernel_map, sizeof(int));
 447                 *arg = x;
 448
 449                 pthread_create(&ap_tids[x], NULL, start_ap, arg);
 450
 451                 while((smp_startup_mask & (1 << x)) == 0)
 452                         cpu_lfence(); /* XXX spin until the AP has started */
 453
 454                 /* XXX hack, sleep for a second to let the APs start up */
 455                 sleep(1);
 456
 457                 /* set cpu0 active so the ap_finish can run*/
 458                 smp_active_mask |= 1;
 459         }
 460
 461         return(ncpus - 1);
 462 }