1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
  24  * Copyright (c) 1983, 2010, Oracle and/or its affiliates. All rights reserved.
  25  * Copyright 2012 Milan Jurik. All rights reserved.
  26  */
  27 
  28 #include <sys/types.h>
  29 #include <sys/time.h>
  30 #include <sys/param.h>
  31 #include <sys/systm.h>
  32 #include <sys/signal.h>
  33 #include <sys/sysmacros.h>
  34 #include <sys/cmn_err.h>
  35 #include <sys/user.h>
  36 #include <sys/proc.h>
  37 #include <sys/task.h>
  38 #include <sys/project.h>
  39 #include <sys/klwp.h>
  40 #include <sys/vnode.h>
  41 #include <sys/file.h>
  42 #include <sys/fcntl.h>
  43 #include <sys/flock.h>
  44 #include <sys/var.h>
  45 #include <sys/stream.h>
  46 #include <sys/strsubr.h>
  47 #include <sys/conf.h>
  48 #include <sys/class.h>
  49 #include <sys/ts.h>
  50 #include <sys/rt.h>
  51 #include <sys/exec.h>
  52 #include <sys/exechdr.h>
  53 #include <sys/buf.h>
  54 #include <sys/resource.h>
  55 #include <vm/seg.h>
  56 #include <vm/pvn.h>
  57 #include <vm/seg_kmem.h>
  58 #include <sys/vmparam.h>
  59 #include <sys/machparam.h>
  60 #include <sys/utsname.h>
  61 #include <sys/kmem.h>
  62 #include <sys/stack.h>
  63 #include <sys/modctl.h>
  64 #include <sys/fdbuffer.h>
  65 #include <sys/cyclic_impl.h>
  66 #include <sys/disp.h>
  67 #include <sys/tuneable.h>
  68 #include <sys/systeminfo.h>
  69 #include <rpc/auth_sys.h>
  70 
  71 #include <sys/vmem.h>
  72 #include <sys/clock.h>
  73 #include <sys/clock_impl.h>
  74 #include <sys/serializer.h>
  75 
  76 /*
  77  * The following few lines describe generic things that must be compiled
  78  * into the booted executable (unix) rather than genunix or any other
  79  * module because they're required by crash dump readers, etc.
  80  */
  81 struct modctl modules;          /* head of linked list of modules */
  82 char *default_path;             /* default module loading path */
  83 struct swapinfo *swapinfo;      /* protected by the swapinfo_lock */
  84 proc_t *practive;               /* active process list */
  85 uint_t nproc;                   /* current number of processes */
  86 proc_t p0;                      /* process 0 */
  87 struct plock p0lock;            /* p0's p_lock */
  88 klwp_t lwp0;                    /* t0's lwp */
  89 task_t *task0p;                 /* task 0 */
  90 kproject_t *proj0p;             /* location of project 0 */
  91 
  92 /*
  93  * The following are "implementation architecture" dependent constants made
  94  * available here in the form of initialized data for use by "implementation
  95  * architecture" independent modules. See machparam.h.
  96  */
  97 const unsigned long     _pagesize       = (unsigned long)PAGESIZE;
  98 const unsigned int      _pageshift      = (unsigned int)PAGESHIFT;
  99 const unsigned long     _pageoffset     = (unsigned long)PAGEOFFSET;
 100 /*
 101  * XXX - This value pagemask has to be a 64bit size because
 102  * large file support uses this mask on offsets which are 64 bit size.
 103  * using unsigned leaves the higher 32 bits value as zero thus
 104  * corrupting offset calculations in the file system and VM.
 105  */
 106 const u_longlong_t      _pagemask       = (u_longlong_t)PAGEMASK;
 107 const unsigned long     _mmu_pagesize   = (unsigned long)MMU_PAGESIZE;
 108 const unsigned int      _mmu_pageshift  = (unsigned int)MMU_PAGESHIFT;
 109 const unsigned long     _mmu_pageoffset = (unsigned long)MMU_PAGEOFFSET;
 110 const unsigned long     _mmu_pagemask   = (unsigned long)MMU_PAGEMASK;
 111 uintptr_t               _kernelbase     = (uintptr_t)KERNELBASE;
 112 uintptr_t               _userlimit      = (uintptr_t)USERLIMIT;
 113 uintptr_t               _userlimit32    = (uintptr_t)USERLIMIT32;
 114 const uintptr_t         _argsbase       = (uintptr_t)ARGSBASE;
 115 const unsigned int      _diskrpm        = (unsigned int)DISKRPM;
 116 const unsigned long     _pgthresh       = (unsigned long)PGTHRESH;
 117 const unsigned int      _maxslp         = (unsigned int)MAXSLP;
 118 const unsigned long     _maxhandspreadpages = (unsigned long)MAXHANDSPREADPAGES;
 119 const int               _ncpu           = (int)NCPU;
 120 const int               _ncpu_log2      = (int)NCPU_LOG2;
 121 const int               _ncpu_p2        = (int)NCPU_P2;
 122 const unsigned long     _defaultstksz   = (unsigned long)DEFAULTSTKSZ;
 123 const unsigned int      _nbpg           = (unsigned int)MMU_PAGESIZE;
 124 
 125 /*
 126  * System parameter formulae.
 127  *
 128  * This file is copied into each directory where we compile
 129  * the kernel; it should be modified there to suit local taste
 130  * if necessary.
 131  */
 132 
 133 /*
 134  * Default hz is 100, but if we set hires_tick we get higher resolution
 135  * clock behavior (currently defined to be 1000 hz).  Higher values seem
 136  * to work, but are not supported.
 137  *
 138  * If we do decide to play with higher values, remember that hz should
 139  * satisfy the following constraints to avoid integer round-off problems:
 140  *
 141  * (1) hz should be in the range 100 <= hz <= MICROSEC.  If hz exceeds
 142  *     MICROSEC, usec_per_tick will be zero and lots of stuff will break.
 143  *     Similarly, if hz < 100 then hz / 100 == 0 and stuff will break.
 144  *
 145  * (2) If hz <= 1000, it should be both a multiple of 100 and a
 146  *      divisor of 1000.
 147  *
 148  * (3) If hz > 1000, it should be both a multiple of 1000 and a
 149  *      divisor of MICROSEC.
 150  *
 151  * Thus the only reasonable values of hz (i.e. the values that won't
 152  * cause roundoff error) are: 100, 200, 500, 1000, 2000, 4000, 5000,
 153  * 8000, 10000, 20000, 25000, 40000, 50000, 100000, 125000, 200000,
 154  * 250000, 500000, 1000000.  As of this writing (1996) a clock rate
 155  * of more than about 10 kHz seems utterly ridiculous, although
 156  * this observation will no doubt seem quaintly amusing one day.
 157  */
 158 #define HIRES_HZ_DEFAULT        1000
 159 
 160 int hz = HZ_DEFAULT;
 161 int hires_hz = HIRES_HZ_DEFAULT;
 162 
 163 volatile int hires_tick = 0;
 164 int cpu_decay_factor = 10;      /* this is no longer tied to clock */
 165 int max_hres_adj;       /* maximum adjustment of hrtime per tick */
 166 int tick_per_msec;      /* clock ticks per millisecond (zero if hz < 1000) */
 167 
 168 /*
 169  * Milliseconds, Microseconds, and Nanoseconds per clock tick
 170  *
 171  * Note:
 172  *  msec_per_tick is zero if hz > 1000
 173  */
 174 int msec_per_tick;
 175 int usec_per_tick;
 176 int nsec_per_tick;
 177 
 178 /*
 179  * Time Resolution values. These are defined in condvar.h and initialized in
 180  * param_init(). Consumers of cv_reltimedwait() and cv_reltimedwait_sig()
 181  * need to specify how accurate the timeout argument should be through
 182  * one of these values. The intention is to allow the underlying implementation
 183  * to anticipate or defer the expiration of timeouts, preventing unnecessary
 184  * wakeups by batch processing similarly expiring events.
 185  */
 186 time_res_t time_res[TR_COUNT];
 187 
 188 /*
 189  * Setting "snooping" to a non-zero value will cause a deadman panic if
 190  * snoop_interval microseconds elapse without lbolt increasing.  The default
 191  * snoop_interval is 50 seconds.
 192  */
 193 #define SNOOP_INTERVAL_MIN      (MICROSEC)
 194 #define SNOOP_INTERVAL_DEFAULT  (50 * MICROSEC)
 195 
 196 int snooping = 0;
 197 uint_t snoop_interval = SNOOP_INTERVAL_DEFAULT;
 198 
 199 /*
 200  * Tables of initialization functions, called from main().
 201  */
 202 
 203 extern void system_taskq_init(void);
 204 extern void binit(void);
 205 extern void space_init(void);
 206 extern void dnlc_init(void);
 207 extern void vfsinit(void);
 208 extern void finit(void);
 209 extern void strinit(void);
 210 extern void flk_init(void);
 211 extern void ftrace_init(void);
 212 extern void softcall_init(void);
 213 extern void ttyinit(void);
 214 extern void schedctl_init(void);
 215 extern void deadman_init(void);
 216 extern void clock_timer_init(void);
 217 extern void clock_realtime_init(void);
 218 extern void clock_highres_init(void);
 219 extern void clock_tick_mp_init(void);
 220 extern void cu_init(void);
 221 extern void callout_mp_init(void);
 222 extern void cpu_seq_tbl_init(void);
 223 
 224 void    (*init_tbl[])(void) = {
 225         system_taskq_init,
 226         binit,
 227         space_init,
 228         dnlc_init,
 229         vfsinit,
 230         finit,
 231         strinit,
 232         serializer_init,
 233         softcall_init,
 234         ttyinit,
 235         as_init,
 236         pvn_init,
 237         anon_init,
 238         segvn_init,
 239         flk_init,
 240         cpu_seq_tbl_init,
 241         schedctl_init,
 242         fdb_init,
 243         deadman_init,
 244         clock_timer_init,
 245         clock_realtime_init,
 246         clock_highres_init,
 247         0
 248 };
 249 
 250 
 251 #if defined(__sparc)
 252         extern void siron_mp_init();
 253 #endif
 254 
 255 /*
 256  * Any per cpu resources should be initialized via
 257  * an entry in mp_init_tbl().
 258  */
 259 void    (*mp_init_tbl[])(void) = {
 260         ftrace_init,
 261         cyclic_mp_init,
 262 #if defined(__sparc)
 263         siron_mp_init,
 264 #endif
 265         clock_tick_mp_init,
 266         cu_init,
 267         callout_mp_init,
 268         0
 269 };
 270 
 271 volatile int maxusers;  /* kitchen-sink knob for dynamic configuration */
 272 
 273 /*
 274  * pidmax -- highest pid value assigned by the system
 275  * Settable in /etc/system
 276  */
 277 volatile int pidmax = DEFAULT_MAXPID;
 278 
 279 /*
 280  * jump_pid - if set, this value is where pid numbers should start
 281  * after the first few system pids (0-3) are used.  If 0, pids are
 282  * chosen in the usual way. This variable can be used to quickly
 283  * create large pids (by setting it to 100000, for example). pids
 284  * less than this value will never be chosen.
 285  */
 286 pid_t jump_pid = DEFAULT_JUMPPID;
 287 
 288 /*
 289  * autoup -- used in struct var for dynamic config of the age a delayed-write
 290  * buffer must be in seconds before bdflush will write it out.
 291  */
 292 #define DEFAULT_AUTOUP  30
 293 volatile int autoup = DEFAULT_AUTOUP;
 294 
 295 /*
 296  * bufhwm -- tuneable variable for struct var for v_bufhwm.
 297  * high water mark for buffer cache mem usage in units of K bytes.
 298  *
 299  * bufhwm_pct -- ditto, but given in % of physmem.
 300  */
 301 volatile int bufhwm = 0;
 302 volatile int bufhwm_pct = 0;
 303 
 304 /*
 305  * Process table.
 306  */
 307 int maxpid;
 308 volatile int max_nprocs;        /* set in param_init() */
 309 volatile int maxuprc;           /* set in param_init() */
 310 volatile int reserved_procs;
 311 int nthread = 1;
 312 
 313 /*
 314  * UFS tunables
 315  */
 316 volatile int ufs_ninode; /* declared here due to backwards compatibility */
 317 volatile int ndquot;     /* declared here due to backwards compatibility */
 318 
 319 /*
 320  * Exec switch table. This is used by the generic exec module
 321  * to switch out to the desired executable type, based on the
 322  * magic number. The currently supported types are ELF, a.out
 323  * (both NMAGIC and ZMAGIC), interpreter (#!) files,
 324  * and Java executables.
 325  */
 326 /*
 327  * Magic numbers
 328  */
 329 short elfmagic = 0x7f45;
 330 short intpmagic = 0x2321;
 331 short jmagic = 0x504b;
 332 
 333 #if defined(__sparc)
 334 short aout_nmagic = NMAGIC;
 335 short aout_zmagic = ZMAGIC;
 336 short aout_omagic = OMAGIC;
 337 #endif
 338 short nomagic = 0;
 339 
 340 /*
 341  * Magic strings
 342  */
 343 #define ELF32MAGIC_STRING       "\x7f""ELF\x1"
 344 #define ELF64MAGIC_STRING       "\x7f""ELF\x2"
 345 #define INTPMAGIC_STRING        "#!"
 346 #define JAVAMAGIC_STRING        "PK\003\004"
 347 #define AOUT_OMAGIC_STRING      "\x1""\x07"     /* 0407 */
 348 #define AOUT_NMAGIC_STRING      "\x1""\x08"     /* 0410 */
 349 #define AOUT_ZMAGIC_STRING      "\x1""\x0b"     /* 0413 */
 350 #define NOMAGIC_STRING          ""
 351 
 352 #define SHBIN_CNTL(x)   ((x)&037)
 353 #define SHBINMAGIC_STRING {SHBIN_CNTL('k'), SHBIN_CNTL('s'), SHBIN_CNTL('h'), 0}
 354 #define SHBINMAGIC_LEN  4
 355 
 356 char elf32magicstr[] = ELF32MAGIC_STRING;
 357 char elf64magicstr[] = ELF64MAGIC_STRING;
 358 char intpmagicstr[] = INTPMAGIC_STRING;
 359 char shbinmagicstr[] = SHBINMAGIC_STRING;
 360 char javamagicstr[] = JAVAMAGIC_STRING;
 361 #if defined(__sparc)
 362 char aout_nmagicstr[] = AOUT_NMAGIC_STRING;
 363 char aout_zmagicstr[] = AOUT_ZMAGIC_STRING;
 364 char aout_omagicstr[] = AOUT_OMAGIC_STRING;
 365 #endif
 366 char nomagicstr[] = NOMAGIC_STRING;
 367 
 368 char *execswnames[] = {
 369         "elfexec",      /* Elf32 */
 370 #ifdef _LP64
 371         "elfexec",      /* Elf64 */
 372 #endif
 373         "intpexec",
 374         "shbinexec",
 375         "javaexec",
 376 #if defined(__sparc)
 377         "aoutexec",
 378         "aoutexec",
 379         "aoutexec",
 380 #endif
 381         NULL,
 382         NULL,
 383         NULL
 384 };
 385 
 386 struct execsw execsw[] = {
 387         { elf32magicstr, 0, 5, NULL, NULL, NULL },
 388 #ifdef _LP64
 389         { elf64magicstr, 0, 5, NULL, NULL, NULL },
 390 #endif
 391         { intpmagicstr, 0, 2, NULL, NULL, NULL },
 392         { shbinmagicstr, 0, SHBINMAGIC_LEN, NULL, NULL, NULL },
 393         { javamagicstr, 0, 4, NULL, NULL, NULL },
 394 #if defined(__sparc)
 395         { aout_zmagicstr, 2, 2, NULL, NULL, NULL },
 396         { aout_nmagicstr, 2, 2, NULL, NULL, NULL },
 397         { aout_omagicstr, 2, 2, NULL, NULL, NULL },
 398 #endif
 399         { nomagicstr, 0, 0, NULL, NULL, NULL },
 400         { nomagicstr, 0, 0, NULL, NULL, NULL },
 401         { nomagicstr, 0, 0, NULL, NULL, NULL },
 402         { nomagicstr, 0, 0, NULL, NULL, NULL }
 403 };
 404 int nexectype = sizeof (execsw) / sizeof (execsw[0]);   /* # of exec types */
 405 kmutex_t execsw_lock;   /* Used for allocation of execsw entries */
 406 
 407 /*
 408  * symbols added to make changing proc.max-file-descriptor
 409  * simple via /etc/system
 410  */
 411 #define RLIM_FD_CUR 0x10000
 412 #define RLIM_FD_MAX 0x10000
 413 
 414 volatile uint_t rlim_fd_cur = RLIM_FD_CUR;
 415 volatile uint_t rlim_fd_max = RLIM_FD_MAX;
 416 
 417 /*
 418  * (Default resource limits were formerly declared here, but are now provided by
 419  * the more general resource controls framework.)
 420  */
 421 
 422 /*
 423  * STREAMS tunables
 424  */
 425 volatile int    nstrpush = 9;   /* maximum # of modules/drivers on a stream */
 426 volatile ssize_t strctlsz = 1024;   /* maximum size of user-generated M_PROTO */
 427 volatile ssize_t strmsgsz = 0x10000; /* maximum size of user-generated M_DATA */
 428                                 /* for `strmsgsz', zero means unlimited */
 429 /*
 430  * Filesystem tunables
 431  */
 432 volatile int    rstchown = 1;   /* POSIX_CHOWN_RESTRICTED is enabled */
 433 int     ngroups_max = NGROUPS_MAX_DEFAULT;
 434 
 435 /*
 436  * generic scheduling stuff
 437  *
 438  * Configurable parameters for RT and TS are in the respective
 439  * scheduling class modules.
 440  */
 441 
 442 pri_t maxclsyspri = MAXCLSYSPRI;
 443 pri_t minclsyspri = MINCLSYSPRI;
 444 char sys_name[] = "SYS";
 445 
 446 extern pri_t sys_init(id_t, int, classfuncs_t **);
 447 extern classfuncs_t sys_classfuncs;
 448 
 449 sclass_t sclass[] = {
 450         { "SYS",        sys_init,       &sys_classfuncs, STATIC_SCHED, 0 },
 451         { "",   NULL,   NULL,   NULL, 0 },
 452         { "",   NULL,   NULL,   NULL, 0 },
 453         { "",   NULL,   NULL,   NULL, 0 },
 454         { "",   NULL,   NULL,   NULL, 0 },
 455         { "",   NULL,   NULL,   NULL, 0 },
 456         { "",   NULL,   NULL,   NULL, 0 },
 457         { "",   NULL,   NULL,   NULL, 0 },
 458         { "",   NULL,   NULL,   NULL, 0 },
 459         { "",   NULL,   NULL,   NULL, 0 }
 460 };
 461 
 462 int loaded_classes = 1;         /* for loaded classes */
 463 kmutex_t class_lock;            /* lock for class[] */
 464 
 465 int nclass = sizeof (sclass) / sizeof (sclass_t);
 466 char initcls[] = "TS";
 467 char *defaultclass = initcls;
 468 
 469 /*
 470  * Tunable system parameters.
 471  */
 472 
 473 /*
 474  * The integers tune_* are done this way so that the tune
 475  * data structure may be "tuned" if necessary from the /etc/system
 476  * file. The tune data structure is initialized in param_init();
 477  */
 478 
 479 tune_t tune;
 480 
 481 /*
 482  * If freemem < t_getpgslow, then start to steal pages from processes.
 483  */
 484 int tune_t_gpgslo = 25;
 485 
 486 /*
 487  * Rate at which fsflush is run, in seconds.
 488  */
 489 #define DEFAULT_TUNE_T_FSFLUSHR 1
 490 volatile int tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
 491 
 492 /*
 493  * The minimum available resident (not swappable) memory to maintain
 494  * in order to avoid deadlock.  In pages.
 495  */
 496 volatile int tune_t_minarmem = 25;
 497 
 498 /*
 499  * The minimum available swappable memory to maintain in order to avoid
 500  * deadlock.  In pages.
 501  */
 502 int tune_t_minasmem = 25;
 503 
 504 int tune_t_flckrec = 512;       /* max # of active frlocks */
 505 
 506 /*
 507  * Number of currently available pages that cannot be 'locked'
 508  * This is set in init_pages_pp_maximum, and must be initialized
 509  * to zero here to detect an override in /etc/system
 510  */
 511 volatile pgcnt_t pages_pp_maximum = 0;
 512 
 513 int boothowto;                  /* boot flags passed to kernel */
 514 struct var v;                   /* System Configuration Information */
 515 
 516 /*
 517  * System Configuration Information
 518  */
 519 
 520 /*
 521  * The physical system's host identifier, expressed as a decimal string.
 522  * Code should only directly access this value when writing to it (setting the
 523  * physical system's host identifier).  Code that reads the physical system's
 524  * host identifier should use zone_get_hostid(NULL) instead.
 525  */
 526 char hw_serial[HW_HOSTID_LEN] = "0";
 527 
 528 #if defined(__sparc)
 529 
 530 /*
 531  * On sparc machines, read hw_serial from the firmware at boot time
 532  * and simply assert Oracle is the hardware provider.
 533  */
 534 char architecture[] = "sparcv9";
 535 char architecture_32[] = "sparc";
 536 char hw_provider[] = "Oracle Corporation";
 537 
 538 #elif defined(__i386)
 539 
 540 char architecture[] = "i386";
 541 char architecture_32[] = "i386";
 542 char hw_provider[SYS_NMLN] = "";
 543 
 544 #elif defined(__amd64)
 545 
 546 char architecture[] = "amd64";
 547 char architecture_32[] = "i386";
 548 char hw_provider[SYS_NMLN] = "";
 549 
 550 #else
 551 #error "unknown processor architecture"
 552 #endif
 553 
 554 char srpc_domain[SYS_NMLN] = "";
 555 char platform[SYS_NMLN] = "";   /* read from the devinfo root node */
 556 
 557 /* Initialize isa_list */
 558 char *isa_list = architecture;
 559 
 560 static pgcnt_t original_physmem = 0;
 561 
 562 #define MIN_DEFAULT_MAXUSERS    8u
 563 #define MAX_DEFAULT_MAXUSERS    2048u
 564 #define MAX_MAXUSERS            4096u
 565 
 566 void
 567 param_preset(void)
 568 {
 569         original_physmem = physmem;
 570 }
 571 
 572 void
 573 param_calc(int platform_max_nprocs)
 574 {
 575         /*
 576          * Default to about one "user" per megabyte, taking into
 577          * account both physical and virtual constraints.
 578          * Note: 2^20 is a meg; shifting right by (20 - PAGESHIFT)
 579          * converts pages to megs without integer overflow.
 580          */
 581 #if defined(__sparc)
 582         if (physmem > original_physmem) {
 583                 physmem = original_physmem;
 584                 cmn_err(CE_NOTE, "physmem limited to %ld", physmem);
 585         }
 586 #endif
 587         if (maxusers == 0) {
 588                 pgcnt_t physmegs = physmem >> (20 - PAGESHIFT);
 589                 pgcnt_t virtmegs = vmem_size(heap_arena, VMEM_FREE) >> 20;
 590                 maxusers = MIN(MAX(MIN(physmegs, virtmegs),
 591                     MIN_DEFAULT_MAXUSERS), MAX_DEFAULT_MAXUSERS);
 592         }
 593         if (maxusers > MAX_MAXUSERS) {
 594                 maxusers = MAX_MAXUSERS;
 595                 cmn_err(CE_NOTE, "maxusers limited to %d", MAX_MAXUSERS);
 596         }
 597 
 598 #ifdef DEBUG
 599         /*
 600          * The purpose of maxusers is to prevent memory overcommit.
 601          * DEBUG kernels take more space, so reduce maxusers a bit.
 602          */
 603         maxusers = (3 * maxusers) / 4;
 604 #endif
 605 
 606         /*
 607          * We need to dynamically change any variables now so that
 608          * the setting of maxusers and pidmax propagate to the other
 609          * variables that are dependent on them.
 610          */
 611         if (reserved_procs == 0)
 612                 reserved_procs = 5;
 613         if (pidmax < reserved_procs || pidmax > MAX_MAXPID)
 614                 maxpid = MAX_MAXPID;
 615         else
 616                 maxpid = pidmax;
 617 
 618         /*
 619          * This allows platform-dependent code to constrain the maximum
 620          * number of processes allowed in case there are e.g. VM limitations
 621          * with how many contexts are available.
 622          */
 623         if (max_nprocs == 0)
 624                 max_nprocs = (10 + 16 * maxusers);
 625         if (platform_max_nprocs > 0 && max_nprocs > platform_max_nprocs)
 626                 max_nprocs = platform_max_nprocs;
 627         if (max_nprocs > maxpid)
 628                 max_nprocs = maxpid;
 629 
 630         if (maxuprc == 0)
 631                 maxuprc = (max_nprocs - reserved_procs);
 632 }
 633 
 634 void
 635 param_init(void)
 636 {
 637         /*
 638          * Set each individual element of struct var v to be the
 639          * default value. This is done this way
 640          * so that a user can set the assigned integer value in the
 641          * /etc/system file *IF* tuning is needed.
 642          */
 643         v.v_proc = max_nprocs;  /* v_proc - max # of processes system wide */
 644         v.v_maxupttl = max_nprocs - reserved_procs;
 645         v.v_maxsyspri = (int)maxclsyspri;  /* max global pri for sysclass */
 646         v.v_maxup = MIN(maxuprc, v.v_maxupttl); /* max procs per user */
 647         v.v_autoup = autoup;    /* v_autoup - delay for delayed writes */
 648 
 649         /*
 650          * Set each individual element of struct tune to be the
 651          * default value. Each struct element This is done this way
 652          *  so that a user can set the assigned integer value in the
 653          * /etc/system file *IF* tuning is needed.
 654          */
 655         tune.t_gpgslo = tune_t_gpgslo;
 656         tune.t_fsflushr = tune_t_fsflushr;
 657         tune.t_minarmem = tune_t_minarmem;
 658         tune.t_minasmem = tune_t_minasmem;
 659         tune.t_flckrec = tune_t_flckrec;
 660 
 661         /*
 662          * Initialization for file descriptors to correct mistaken settings in
 663          * /etc/system.  Initialization of limits performed by resource control
 664          * system.
 665          */
 666         if (rlim_fd_cur > rlim_fd_max)
 667                 rlim_fd_cur = rlim_fd_max;
 668 
 669         /*
 670          * calculations needed if hz was set in /etc/system
 671          */
 672         if (hires_tick)
 673                 hz = hires_hz;
 674 
 675         tick_per_msec = hz / MILLISEC;
 676         msec_per_tick = MILLISEC / hz;
 677         usec_per_tick = MICROSEC / hz;
 678         nsec_per_tick = NANOSEC / hz;
 679         max_hres_adj = nsec_per_tick >> ADJ_SHIFT;
 680 
 681         /*
 682          * Consumers of relative timedwait functions must specify how accurately
 683          * the given timeout must expire. This is currently TR_CLOCK_TICK for
 684          * the vast majority of consumers, but nsec_per_tick becomes an
 685          * artificial value in a tickless world. Each caller of such routines
 686          * should re-evaluate their usage and specify the appropriate
 687          * resolution.
 688          */
 689         time_res[TR_NANOSEC] = NANOSEC / NANOSEC;
 690         time_res[TR_MICROSEC] = NANOSEC / MICROSEC;
 691         time_res[TR_MILLISEC] = NANOSEC / MILLISEC;
 692         time_res[TR_SEC] = NANOSEC / SEC;
 693         time_res[TR_CLOCK_TICK] = nsec_per_tick;
 694 }
 695 
 696 /*
 697  * Validate tuneable parameters following /etc/system processing,
 698  * but prior to param_init().
 699  */
 700 void
 701 param_check(void)
 702 {
 703 #if defined(__x86)
 704         if (physmem != original_physmem) {
 705                 cmn_err(CE_NOTE, "physmem cannot be modified to 0x%lx"
 706                     " via /etc/system. Please use eeprom(1M) instead.",
 707                     physmem);
 708                 physmem = original_physmem;
 709         }
 710 #endif
 711         if (ngroups_max < NGROUPS_UMIN)
 712                 ngroups_max = NGROUPS_UMIN;
 713         if (ngroups_max > NGROUPS_UMAX)
 714                 ngroups_max = NGROUPS_UMAX;
 715 
 716         /* If we have many groups then the ucred proto message also grows. */
 717         if (ngroups_max > NGROUPS_OLDMAX &&
 718             strctlsz < (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) + 1024) {
 719                 strctlsz = (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) +
 720                     1024;
 721         }
 722 
 723         if (autoup <= 0) {
 724                 autoup = DEFAULT_AUTOUP;
 725                 cmn_err(CE_WARN, "autoup <= 0; defaulting to %d", autoup);
 726         }
 727 
 728         if (tune_t_fsflushr <= 0) {
 729                 tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
 730                 cmn_err(CE_WARN, "tune_t_fsflushr <= 0; defaulting to %d",
 731                     tune_t_fsflushr);
 732         }
 733 
 734         if (jump_pid < 0 || jump_pid >= pidmax) {
 735                 jump_pid = 0;
 736                 cmn_err(CE_WARN, "jump_pid < 0 or >= pidmax; ignored");
 737         }
 738 
 739         if (snoop_interval < SNOOP_INTERVAL_MIN) {
 740                 snoop_interval = SNOOP_INTERVAL_DEFAULT;
 741                 cmn_err(CE_WARN, "snoop_interval < minimum (%d); defaulting"
 742                     " to %d", SNOOP_INTERVAL_MIN, SNOOP_INTERVAL_DEFAULT);
 743         }
 744 }