sys/vm/vm_zone.c

   1 /*
   2  * (MPSAFE)
   3  *
   4  * Copyright (c) 1997, 1998 John S. Dyson
   5  * All rights reserved.
   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  * 1. Redistributions of source code must retain the above copyright
  11  *      notice immediately at the beginning of the file, without modification,
  12  *      this list of conditions, and the following disclaimer.
  13  * 2. Absolutely no warranty of function or purpose is made by the author
  14  *      John S. Dyson.
  15  *
  16  * $FreeBSD: src/sys/vm/vm_zone.c,v 1.30.2.6 2002/10/10 19:50:16 dillon Exp $
  17  */
  18
  19 #include <sys/param.h>
  20 #include <sys/queue.h>
  21 #include <sys/systm.h>
  22 #include <sys/kernel.h>
  23 #include <sys/lock.h>
  24 #include <sys/malloc.h>
  25 #include <sys/sysctl.h>
  26 #include <sys/vmmeter.h>
  27
  28 #include <vm/vm.h>
  29 #include <vm/vm_object.h>
  30 #include <vm/vm_page.h>
  31 #include <vm/vm_map.h>
  32 #include <vm/vm_kern.h>
  33 #include <vm/vm_extern.h>
  34 #include <vm/vm_zone.h>
  35
  36 #include <sys/spinlock2.h>
  37 #include <vm/vm_page2.h>
  38
  39 static MALLOC_DEFINE(M_ZONE, "ZONE", "Zone header");
  40
  41 #define ZONE_ERROR_INVALID 0
  42 #define ZONE_ERROR_NOTFREE 1
  43 #define ZONE_ERROR_ALREADYFREE 2
  44
  45 #define ZONE_ROUNDING   32
  46
  47 #define ZENTRY_FREE     0x12342378
  48
  49 int zone_burst = 32;
  50
  51 static void *zget(vm_zone_t z);
  52
  53 /*
  54  * Return an item from the specified zone.   This function is non-blocking for
  55  * ZONE_INTERRUPT zones.
  56  *
  57  * No requirements.
  58  */
  59 void *
  60 zalloc(vm_zone_t z)
  61 {
  62         globaldata_t gd = mycpu;
  63         void *item;
  64         int n;
  65
  66 #ifdef INVARIANTS
  67         if (z == NULL)
  68                 zerror(ZONE_ERROR_INVALID);
  69 #endif
  70 retry:
  71         /*
  72          * Avoid spinlock contention by allocating from a per-cpu queue
  73          */
  74         if (z->zfreecnt_pcpu[gd->gd_cpuid] > 0) {
  75                 crit_enter_gd(gd);
  76                 if (z->zfreecnt_pcpu[gd->gd_cpuid] > 0) {
  77                         item = z->zitems_pcpu[gd->gd_cpuid];
  78 #ifdef INVARIANTS
  79                         KASSERT(item != NULL,
  80                                 ("zitems_pcpu unexpectedly NULL"));
  81                         if (((void **)item)[1] != (void *)ZENTRY_FREE)
  82                                 zerror(ZONE_ERROR_NOTFREE);
  83                         ((void **)item)[1] = NULL;
  84 #endif
  85                         z->zitems_pcpu[gd->gd_cpuid] = ((void **) item)[0];
  86                         --z->zfreecnt_pcpu[gd->gd_cpuid];
  87                         z->znalloc++;
  88                         crit_exit_gd(gd);
  89                         return item;
  90                 }
  91                 crit_exit_gd(gd);
  92         }
  93
  94         /*
  95          * Per-zone spinlock for the remainder.  Always load at least one
  96          * item.
  97          */
  98         spin_lock(&z->zlock);
  99         if (z->zfreecnt > z->zfreemin) {
 100                 n = zone_burst;
 101                 do {
 102                         item = z->zitems;
 103 #ifdef INVARIANTS
 104                         KASSERT(item != NULL, ("zitems unexpectedly NULL"));
 105                         if (((void **)item)[1] != (void *)ZENTRY_FREE)
 106                                 zerror(ZONE_ERROR_NOTFREE);
 107 #endif
 108                         z->zitems = ((void **)item)[0];
 109                         z->zfreecnt--;
 110                         ((void **)item)[0] = z->zitems_pcpu[gd->gd_cpuid];
 111                         z->zitems_pcpu[gd->gd_cpuid] = item;
 112                         ++z->zfreecnt_pcpu[gd->gd_cpuid];
 113                 } while (--n > 0 && z->zfreecnt > z->zfreemin);
 114                 spin_unlock(&z->zlock);
 115                 goto retry;
 116         } else {
 117                 spin_unlock(&z->zlock);
 118                 item = zget(z);
 119                 /*
 120                  * PANICFAIL allows the caller to assume that the zalloc()
 121                  * will always succeed.  If it doesn't, we panic here.
 122                  */
 123                 if (item == NULL && (z->zflags & ZONE_PANICFAIL))
 124                         panic("zalloc(%s) failed", z->zname);
 125         }
 126         return item;
 127 }
 128
 129 /*
 130  * Free an item to the specified zone.
 131  *
 132  * No requirements.
 133  */
 134 void
 135 zfree(vm_zone_t z, void *item)
 136 {
 137         globaldata_t gd = mycpu;
 138         int zmax;
 139
 140         /*
 141          * Avoid spinlock contention by freeing into a per-cpu queue
 142          */
 143         if ((zmax = z->zmax) != 0)
 144                 zmax = zmax / ncpus / 16;
 145         if (zmax < 64)
 146                 zmax = 64;
 147
 148         if (z->zfreecnt_pcpu[gd->gd_cpuid] < zmax) {
 149                 crit_enter_gd(gd);
 150                 ((void **)item)[0] = z->zitems_pcpu[gd->gd_cpuid];
 151 #ifdef INVARIANTS
 152                 if (((void **)item)[1] == (void *)ZENTRY_FREE)
 153                         zerror(ZONE_ERROR_ALREADYFREE);
 154                 ((void **)item)[1] = (void *)ZENTRY_FREE;
 155 #endif
 156                 z->zitems_pcpu[gd->gd_cpuid] = item;
 157                 ++z->zfreecnt_pcpu[gd->gd_cpuid];
 158                 crit_exit_gd(gd);
 159                 return;
 160         }
 161
 162         /*
 163          * Per-zone spinlock for the remainder.
 164          */
 165         spin_lock(&z->zlock);
 166         ((void **)item)[0] = z->zitems;
 167 #ifdef INVARIANTS
 168         if (((void **)item)[1] == (void *)ZENTRY_FREE)
 169                 zerror(ZONE_ERROR_ALREADYFREE);
 170         ((void **)item)[1] = (void *)ZENTRY_FREE;
 171 #endif
 172         z->zitems = item;
 173         z->zfreecnt++;
 174         spin_unlock(&z->zlock);
 175 }
 176
 177 /*
 178  * This file comprises a very simple zone allocator.  This is used
 179  * in lieu of the malloc allocator, where needed or more optimal.
 180  *
 181  * Note that the initial implementation of this had coloring, and
 182  * absolutely no improvement (actually perf degradation) occurred.
 183  *
 184  * Note also that the zones are type stable.  The only restriction is
 185  * that the first two longwords of a data structure can be changed
 186  * between allocations.  Any data that must be stable between allocations
 187  * must reside in areas after the first two longwords.
 188  *
 189  * zinitna, zinit, zbootinit are the initialization routines.
 190  * zalloc, zfree, are the allocation/free routines.
 191  */
 192
 193 LIST_HEAD(zlist, vm_zone) zlist = LIST_HEAD_INITIALIZER(zlist);
 194 static int sysctl_vm_zone(SYSCTL_HANDLER_ARGS);
 195 static int zone_kmem_pages, zone_kern_pages;
 196 static long zone_kmem_kvaspace;
 197
 198 /*
 199  * Create a zone, but don't allocate the zone structure.  If the
 200  * zone had been previously created by the zone boot code, initialize
 201  * various parts of the zone code.
 202  *
 203  * If waits are not allowed during allocation (e.g. during interrupt
 204  * code), a-priori allocate the kernel virtual space, and allocate
 205  * only pages when needed.
 206  *
 207  * Arguments:
 208  * z            pointer to zone structure.
 209  * obj          pointer to VM object (opt).
 210  * name         name of zone.
 211  * size         size of zone entries.
 212  * nentries     number of zone entries allocated (only ZONE_INTERRUPT.)
 213  * flags        ZONE_INTERRUPT -- items can be allocated at interrupt time.
 214  * zalloc       number of pages allocated when memory is needed.
 215  *
 216  * Note that when using ZONE_INTERRUPT, the size of the zone is limited
 217  * by the nentries argument.  The size of the memory allocatable is
 218  * unlimited if ZONE_INTERRUPT is not set.
 219  *
 220  * No requirements.
 221  */
 222 int
 223 zinitna(vm_zone_t z, vm_object_t obj, char *name, int size,
 224         int nentries, int flags, int zalloc)
 225 {
 226         size_t totsize;
 227
 228         /*
 229          * Only zones created with zinit() are destroyable.
 230          */
 231         if (z->zflags & ZONE_DESTROYABLE)
 232                 panic("zinitna: can't create destroyable zone");
 233
 234         /*
 235          * NOTE: We can only adjust zsize if we previously did not
 236          *       use zbootinit().
 237          */
 238         if ((z->zflags & ZONE_BOOT) == 0) {
 239                 z->zsize = roundup2(size, ZONE_ROUNDING);
 240                 spin_init(&z->zlock, "zinitna");
 241                 z->zfreecnt = 0;
 242                 z->ztotal = 0;
 243                 z->zmax = 0;
 244                 z->zname = name;
 245                 z->znalloc = 0;
 246                 z->zitems = NULL;
 247
 248                 lwkt_gettoken(&vm_token);
 249                 LIST_INSERT_HEAD(&zlist, z, zlink);
 250                 lwkt_reltoken(&vm_token);
 251
 252                 bzero(z->zitems_pcpu, sizeof(z->zitems_pcpu));
 253                 bzero(z->zfreecnt_pcpu, sizeof(z->zfreecnt_pcpu));
 254         }
 255
 256         z->zkmvec = NULL;
 257         z->zkmcur = z->zkmmax = 0;
 258         z->zflags |= flags;
 259
 260         /*
 261          * If we cannot wait, allocate KVA space up front, and we will fill
 262          * in pages as needed.  This is particularly required when creating
 263          * an allocation space for map entries in kernel_map, because we
 264          * do not want to go into a recursion deadlock with
 265          * vm_map_entry_reserve().
 266          */
 267         if (z->zflags & ZONE_INTERRUPT) {
 268                 totsize = round_page((size_t)z->zsize * nentries);
 269                 atomic_add_long(&zone_kmem_kvaspace, totsize);
 270
 271                 z->zkva = kmem_alloc_pageable(&kernel_map, totsize);
 272                 if (z->zkva == 0) {
 273                         LIST_REMOVE(z, zlink);
 274                         return 0;
 275                 }
 276
 277                 z->zpagemax = totsize / PAGE_SIZE;
 278                 if (obj == NULL) {
 279                         z->zobj = vm_object_allocate(OBJT_DEFAULT, z->zpagemax);
 280                 } else {
 281                         z->zobj = obj;
 282                         _vm_object_allocate(OBJT_DEFAULT, z->zpagemax, obj);
 283                         vm_object_drop(obj);
 284                 }
 285                 z->zallocflag = VM_ALLOC_SYSTEM | VM_ALLOC_INTERRUPT |
 286                                 VM_ALLOC_NORMAL | VM_ALLOC_RETRY;
 287                 z->zmax += nentries;
 288         } else {
 289                 z->zallocflag = VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM;
 290                 z->zmax = 0;
 291         }
 292
 293
 294         if (z->zsize > PAGE_SIZE)
 295                 z->zfreemin = 1;
 296         else
 297                 z->zfreemin = PAGE_SIZE / z->zsize;
 298
 299         z->zpagecount = 0;
 300         if (zalloc)
 301                 z->zalloc = zalloc;
 302         else
 303                 z->zalloc = 1;
 304
 305         /*
 306          * Populate the interrrupt zone at creation time rather than
 307          * on first allocation, as this is a potentially long operation.
 308          */
 309         if (z->zflags & ZONE_INTERRUPT) {
 310                 void *buf;
 311
 312                 buf = zget(z);
 313                 zfree(z, buf);
 314         }
 315
 316         return 1;
 317 }
 318
 319 /*
 320  * Subroutine same as zinitna, except zone data structure is allocated
 321  * automatically by malloc.  This routine should normally be used, except
 322  * in certain tricky startup conditions in the VM system -- then
 323  * zbootinit and zinitna can be used.  Zinit is the standard zone
 324  * initialization call.
 325  *
 326  * No requirements.
 327  */
 328 vm_zone_t
 329 zinit(char *name, int size, int nentries, int flags, int zalloc)
 330 {
 331         vm_zone_t z;
 332
 333         z = (vm_zone_t) kmalloc(sizeof (struct vm_zone), M_ZONE, M_NOWAIT);
 334         if (z == NULL)
 335                 return NULL;
 336
 337         z->zflags = 0;
 338         if (zinitna(z, NULL, name, size, nentries,
 339                     flags & ~ZONE_DESTROYABLE, zalloc) == 0) {
 340                 kfree(z, M_ZONE);
 341                 return NULL;
 342         }
 343
 344         if (flags & ZONE_DESTROYABLE)
 345                 z->zflags |= ZONE_DESTROYABLE;
 346
 347         return z;
 348 }
 349
 350 /*
 351  * Initialize a zone before the system is fully up.  This routine should
 352  * only be called before full VM startup.
 353  *
 354  * Called from the low level boot code only.
 355  */
 356 void
 357 zbootinit(vm_zone_t z, char *name, int size, void *item, int nitems)
 358 {
 359         int i;
 360
 361         bzero(z->zitems_pcpu, sizeof(z->zitems_pcpu));
 362         bzero(z->zfreecnt_pcpu, sizeof(z->zfreecnt_pcpu));
 363
 364         z->zname = name;
 365         z->zsize = size;
 366         z->zpagemax = 0;
 367         z->zobj = NULL;
 368         z->zflags = ZONE_BOOT;
 369         z->zfreemin = 0;
 370         z->zallocflag = 0;
 371         z->zpagecount = 0;
 372         z->zalloc = 0;
 373         z->znalloc = 0;
 374         spin_init(&z->zlock, "zbootinit");
 375
 376         bzero(item, (size_t)nitems * z->zsize);
 377         z->zitems = NULL;
 378         for (i = 0; i < nitems; i++) {
 379                 ((void **)item)[0] = z->zitems;
 380 #ifdef INVARIANTS
 381                 ((void **)item)[1] = (void *)ZENTRY_FREE;
 382 #endif
 383                 z->zitems = item;
 384                 item = (uint8_t *)item + z->zsize;
 385         }
 386         z->zfreecnt = nitems;
 387         z->zmax = nitems;
 388         z->ztotal = nitems;
 389
 390         lwkt_gettoken(&vm_token);
 391         LIST_INSERT_HEAD(&zlist, z, zlink);
 392         lwkt_reltoken(&vm_token);
 393 }
 394
 395 /*
 396  * Release all resources owned by zone created with zinit().
 397  *
 398  * No requirements.
 399  */
 400 void
 401 zdestroy(vm_zone_t z)
 402 {
 403         vm_page_t m;
 404         int i;
 405
 406         if (z == NULL)
 407                 panic("zdestroy: null zone");
 408         if ((z->zflags & ZONE_DESTROYABLE) == 0)
 409                 panic("zdestroy: undestroyable zone");
 410
 411         lwkt_gettoken(&vm_token);
 412         LIST_REMOVE(z, zlink);
 413         lwkt_reltoken(&vm_token);
 414
 415         /*
 416          * Release virtual mappings, physical memory and update sysctl stats.
 417          */
 418         if (z->zflags & ZONE_INTERRUPT) {
 419                 /*
 420                  * Pages mapped via pmap_kenter() must be removed from the
 421                  * kernel_pmap() before calling kmem_free() to avoid issues
 422                  * with kernel_pmap.pm_stats.resident_count.
 423                  */
 424                 pmap_qremove(z->zkva, z->zpagemax);
 425                 vm_object_hold(z->zobj);
 426                 for (i = 0; i < z->zpagecount; ++i) {
 427                         m = vm_page_lookup_busy_wait(z->zobj, i, TRUE, "vmzd");
 428                         vm_page_unwire(m, 0);
 429                         vm_page_free(m);
 430                 }
 431
 432                 /*
 433                  * Free the mapping.
 434                  */
 435                 kmem_free(&kernel_map, z->zkva,
 436                           (size_t)z->zpagemax * PAGE_SIZE);
 437                 atomic_subtract_long(&zone_kmem_kvaspace,
 438                                      (size_t)z->zpagemax * PAGE_SIZE);
 439
 440                 /*
 441                  * Free the backing object and physical pages.
 442                  */
 443                 vm_object_deallocate(z->zobj);
 444                 vm_object_drop(z->zobj);
 445                 atomic_subtract_int(&zone_kmem_pages, z->zpagecount);
 446         } else {
 447                 for (i=0; i < z->zkmcur; i++) {
 448                         kmem_free(&kernel_map, z->zkmvec[i],
 449                                   (size_t)z->zalloc * PAGE_SIZE);
 450                         atomic_subtract_int(&zone_kern_pages, z->zalloc);
 451                 }
 452                 if (z->zkmvec != NULL)
 453                         kfree(z->zkmvec, M_ZONE);
 454         }
 455
 456         spin_uninit(&z->zlock);
 457         kfree(z, M_ZONE);
 458 }
 459
 460
 461 /*
 462  * void *zalloc(vm_zone_t zone) --
 463  *      Returns an item from a specified zone.  May not be called from a
 464  *      FAST interrupt or IPI function.
 465  *
 466  * void zfree(vm_zone_t zone, void *item) --
 467  *      Frees an item back to a specified zone.  May not be called from a
 468  *      FAST interrupt or IPI function.
 469  */
 470
 471 /*
 472  * Internal zone routine.  Not to be called from external (non vm_zone) code.
 473  *
 474  * No requirements.
 475  */
 476 static void *
 477 zget(vm_zone_t z)
 478 {
 479         int i;
 480         vm_page_t m;
 481         int nitems;
 482         int npages;
 483         int savezpc;
 484         size_t nbytes;
 485         size_t noffset;
 486         void *item;
 487
 488         if (z == NULL)
 489                 panic("zget: null zone");
 490
 491         if (z->zflags & ZONE_INTERRUPT) {
 492                 /*
 493                  * Interrupt zones do not mess with the kernel_map, they
 494                  * simply populate an existing mapping.
 495                  *
 496                  * First reserve the required space.
 497                  */
 498                 vm_object_hold(z->zobj);
 499                 noffset = (size_t)z->zpagecount * PAGE_SIZE;
 500                 noffset -= noffset % z->zsize;
 501                 savezpc = z->zpagecount;
 502                 if (z->zpagecount + z->zalloc > z->zpagemax)
 503                         z->zpagecount = z->zpagemax;
 504                 else
 505                         z->zpagecount += z->zalloc;
 506                 item = (char *)z->zkva + noffset;
 507                 npages = z->zpagecount - savezpc;
 508                 nitems = ((size_t)(savezpc + npages) * PAGE_SIZE - noffset) /
 509                          z->zsize;
 510                 atomic_add_int(&zone_kmem_pages, npages);
 511
 512                 /*
 513                  * Now allocate the pages.  Note that we can block in the
 514                  * loop, so we've already done all the necessary calculations
 515                  * and reservations above.
 516                  */
 517                 for (i = 0; i < npages; ++i) {
 518                         vm_offset_t zkva;
 519
 520                         m = vm_page_alloc(z->zobj, savezpc + i, z->zallocflag);
 521                         KKASSERT(m != NULL);
 522                         /* note: z might be modified due to blocking */
 523
 524                         KKASSERT(m->queue == PQ_NONE);
 525                         m->valid = VM_PAGE_BITS_ALL;
 526                         vm_page_wire(m);
 527                         vm_page_wakeup(m);
 528
 529                         zkva = z->zkva + (size_t)(savezpc + i) * PAGE_SIZE;
 530                         pmap_kenter(zkva, VM_PAGE_TO_PHYS(m));
 531                         bzero((void *)zkva, PAGE_SIZE);
 532                 }
 533                 vm_object_drop(z->zobj);
 534         } else if (z->zflags & ZONE_SPECIAL) {
 535                 /*
 536                  * The special zone is the one used for vm_map_entry_t's.
 537                  * We have to avoid an infinite recursion in
 538                  * vm_map_entry_reserve() by using vm_map_entry_kreserve()
 539                  * instead.  The map entries are pre-reserved by the kernel
 540                  * by vm_map_entry_reserve_cpu_init().
 541                  */
 542                 nbytes = (size_t)z->zalloc * PAGE_SIZE;
 543
 544                 item = (void *)kmem_alloc3(&kernel_map, nbytes, KM_KRESERVE);
 545
 546                 /* note: z might be modified due to blocking */
 547                 if (item != NULL) {
 548                         zone_kern_pages += z->zalloc;   /* not MP-safe XXX */
 549                         bzero(item, nbytes);
 550                 } else {
 551                         nbytes = 0;
 552                 }
 553                 nitems = nbytes / z->zsize;
 554         } else {
 555                 /*
 556                  * Otherwise allocate KVA from the kernel_map.
 557                  */
 558                 nbytes = (size_t)z->zalloc * PAGE_SIZE;
 559
 560                 item = (void *)kmem_alloc3(&kernel_map, nbytes, 0);
 561
 562                 /* note: z might be modified due to blocking */
 563                 if (item != NULL) {
 564                         zone_kern_pages += z->zalloc;   /* not MP-safe XXX */
 565                         bzero(item, nbytes);
 566
 567                         if (z->zflags & ZONE_DESTROYABLE) {
 568                                 if (z->zkmcur == z->zkmmax) {
 569                                         z->zkmmax =
 570                                                 z->zkmmax==0 ? 1 : z->zkmmax*2;
 571                                         z->zkmvec = krealloc(z->zkmvec,
 572                                             z->zkmmax * sizeof(z->zkmvec[0]),
 573                                             M_ZONE, M_WAITOK);
 574                                 }
 575                                 z->zkmvec[z->zkmcur++] = (vm_offset_t)item;
 576                         }
 577                 } else {
 578                         nbytes = 0;
 579                 }
 580                 nitems = nbytes / z->zsize;
 581         }
 582
 583         spin_lock(&z->zlock);
 584         z->ztotal += nitems;
 585         /*
 586          * Save one for immediate allocation
 587          */
 588         if (nitems != 0) {
 589                 nitems -= 1;
 590                 for (i = 0; i < nitems; i++) {
 591                         ((void **)item)[0] = z->zitems;
 592 #ifdef INVARIANTS
 593                         ((void **)item)[1] = (void *)ZENTRY_FREE;
 594 #endif
 595                         z->zitems = item;
 596                         item = (uint8_t *)item + z->zsize;
 597                 }
 598                 z->zfreecnt += nitems;
 599                 z->znalloc++;
 600         } else if (z->zfreecnt > 0) {
 601                 item = z->zitems;
 602                 z->zitems = ((void **)item)[0];
 603 #ifdef INVARIANTS
 604                 if (((void **)item)[1] != (void *)ZENTRY_FREE)
 605                         zerror(ZONE_ERROR_NOTFREE);
 606                 ((void **) item)[1] = NULL;
 607 #endif
 608                 z->zfreecnt--;
 609                 z->znalloc++;
 610         } else {
 611                 item = NULL;
 612         }
 613         spin_unlock(&z->zlock);
 614
 615         /*
 616          * A special zone may have used a kernel-reserved vm_map_entry.  If
 617          * so we have to be sure to recover our reserve so we don't run out.
 618          * We will panic if we run out.
 619          */
 620         if (z->zflags & ZONE_SPECIAL)
 621                 vm_map_entry_reserve(0);
 622
 623         return item;
 624 }
 625
 626 /*
 627  * No requirements.
 628  */
 629 static int
 630 sysctl_vm_zone(SYSCTL_HANDLER_ARGS)
 631 {
 632         int error=0;
 633         vm_zone_t curzone;
 634         char tmpbuf[128];
 635         char tmpname[14];
 636
 637         ksnprintf(tmpbuf, sizeof(tmpbuf),
 638             "\nITEM            SIZE     LIMIT    USED    FREE  REQUESTS\n");
 639         error = SYSCTL_OUT(req, tmpbuf, strlen(tmpbuf));
 640         if (error)
 641                 return (error);
 642
 643         lwkt_gettoken(&vm_token);
 644         LIST_FOREACH(curzone, &zlist, zlink) {
 645                 int i;
 646                 int n;
 647                 int len;
 648                 int offset;
 649                 int freecnt;
 650
 651                 len = strlen(curzone->zname);
 652                 if (len >= (sizeof(tmpname) - 1))
 653                         len = (sizeof(tmpname) - 1);
 654                 for(i = 0; i < sizeof(tmpname) - 1; i++)
 655                         tmpname[i] = ' ';
 656                 tmpname[i] = 0;
 657                 memcpy(tmpname, curzone->zname, len);
 658                 tmpname[len] = ':';
 659                 offset = 0;
 660                 if (curzone == LIST_FIRST(&zlist)) {
 661                         offset = 1;
 662                         tmpbuf[0] = '\n';
 663                 }
 664                 freecnt = curzone->zfreecnt;
 665                 for (n = 0; n < ncpus; ++n)
 666                         freecnt += curzone->zfreecnt_pcpu[n];
 667
 668                 ksnprintf(tmpbuf + offset, sizeof(tmpbuf) - offset,
 669                         "%s %6.6u, %8.8u, %6.6u, %6.6u, %8.8u\n",
 670                         tmpname, curzone->zsize, curzone->zmax,
 671                         (curzone->ztotal - freecnt),
 672                         freecnt, curzone->znalloc);
 673
 674                 len = strlen((char *)tmpbuf);
 675                 if (LIST_NEXT(curzone, zlink) == NULL)
 676                         tmpbuf[len - 1] = 0;
 677
 678                 error = SYSCTL_OUT(req, tmpbuf, len);
 679
 680                 if (error)
 681                         break;
 682         }
 683         lwkt_reltoken(&vm_token);
 684         return (error);
 685 }
 686
 687 #if defined(INVARIANTS)
 688
 689 /*
 690  * Debugging only.
 691  */
 692 void
 693 zerror(int error)
 694 {
 695         char *msg;
 696
 697         switch (error) {
 698         case ZONE_ERROR_INVALID:
 699                 msg = "zone: invalid zone";
 700                 break;
 701         case ZONE_ERROR_NOTFREE:
 702                 msg = "zone: entry not free";
 703                 break;
 704         case ZONE_ERROR_ALREADYFREE:
 705                 msg = "zone: freeing free entry";
 706                 break;
 707         default:
 708                 msg = "zone: invalid error";
 709                 break;
 710         }
 711         panic("%s", msg);
 712 }
 713 #endif
 714
 715 SYSCTL_OID(_vm, OID_AUTO, zone, CTLTYPE_STRING|CTLFLAG_RD, \
 716         NULL, 0, sysctl_vm_zone, "A", "Zone Info");
 717
 718 SYSCTL_INT(_vm, OID_AUTO, zone_kmem_pages,
 719         CTLFLAG_RD, &zone_kmem_pages, 0, "Number of interrupt safe pages allocated by zone");
 720 SYSCTL_INT(_vm, OID_AUTO, zone_burst,
 721         CTLFLAG_RW, &zone_burst, 0, "Burst from depot to pcpu cache");
 722 SYSCTL_LONG(_vm, OID_AUTO, zone_kmem_kvaspace,
 723         CTLFLAG_RD, &zone_kmem_kvaspace, 0, "KVA space allocated by zone");
 724 SYSCTL_INT(_vm, OID_AUTO, zone_kern_pages,
 725         CTLFLAG_RD, &zone_kern_pages, 0, "Number of non-interrupt safe pages allocated by zone");