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 
  70 #include <sys/vmem.h>
  71 #include <sys/clock.h>
  72 #include <sys/clock_impl.h>
  73 #include <sys/serializer.h>
  74 
  75 /*
  76  * The following few lines describe generic things that must be compiled
  77  * into the booted executable (unix) rather than genunix or any other
  78  * module because they're required by crash dump readers, etc.
  79  */
  80 struct modctl modules;          /* head of linked list of modules */
  81 char *default_path;             /* default module loading path */
  82 struct swapinfo *swapinfo;      /* protected by the swapinfo_lock */
  83 proc_t *practive;               /* active process list */
  84 uint_t nproc;                   /* current number of processes */
  85 proc_t p0;                      /* process 0 */
  86 struct plock p0lock;            /* p0's p_lock */
  87 klwp_t lwp0;                    /* t0's lwp */
  88 task_t *task0p;                 /* task 0 */
  89 kproject_t *proj0p;             /* location of project 0 */
  90 
  91 /*
  92  * The following are "implementation architecture" dependent constants made
  93  * available here in the form of initialized data for use by "implementation
  94  * architecture" independent modules. See machparam.h.
  95  */
  96 const unsigned long     _pagesize       = (unsigned long)PAGESIZE;
  97 const unsigned int      _pageshift      = (unsigned int)PAGESHIFT;
  98 const unsigned long     _pageoffset     = (unsigned long)PAGEOFFSET;
  99 /*
 100  * XXX - This value pagemask has to be a 64bit size because
 101  * large file support uses this mask on offsets which are 64 bit size.
 102  * using unsigned leaves the higher 32 bits value as zero thus
 103  * corrupting offset calculations in the file system and VM.
 104  */
 105 const u_longlong_t      _pagemask       = (u_longlong_t)PAGEMASK;
 106 const unsigned long     _mmu_pagesize   = (unsigned long)MMU_PAGESIZE;
 107 const unsigned int      _mmu_pageshift  = (unsigned int)MMU_PAGESHIFT;
 108 const unsigned long     _mmu_pageoffset = (unsigned long)MMU_PAGEOFFSET;
 109 const unsigned long     _mmu_pagemask   = (unsigned long)MMU_PAGEMASK;
 110 uintptr_t               _kernelbase     = (uintptr_t)KERNELBASE;
 111 uintptr_t               _userlimit      = (uintptr_t)USERLIMIT;
 112 uintptr_t               _userlimit32    = (uintptr_t)USERLIMIT32;
 113 const uintptr_t         _argsbase       = (uintptr_t)ARGSBASE;
 114 const unsigned int      _diskrpm        = (unsigned int)DISKRPM;
 115 const unsigned long     _pgthresh       = (unsigned long)PGTHRESH;
 116 const unsigned int      _maxslp         = (unsigned int)MAXSLP;
 117 const unsigned long     _maxhandspreadpages = (unsigned long)MAXHANDSPREADPAGES;
 118 const int               _ncpu           = (int)NCPU;
 119 const int               _ncpu_log2      = (int)NCPU_LOG2;
 120 const int               _ncpu_p2        = (int)NCPU_P2;
 121 const unsigned long     _defaultstksz   = (unsigned long)DEFAULTSTKSZ;
 122 const unsigned int      _nbpg           = (unsigned int)MMU_PAGESIZE;
 123 
 124 /*
 125  * System parameter formulae.
 126  *
 127  * This file is copied into each directory where we compile
 128  * the kernel; it should be modified there to suit local taste
 129  * if necessary.
 130  */
 131 
 132 /*
 133  * Default hz is 100, but if we set hires_tick we get higher resolution
 134  * clock behavior (currently defined to be 1000 hz).  Higher values seem
 135  * to work, but are not supported.
 136  *
 137  * If we do decide to play with higher values, remember that hz should
 138  * satisfy the following constraints to avoid integer round-off problems:
 139  *
 140  * (1) hz should be in the range 100 <= hz <= MICROSEC.  If hz exceeds
 141  *     MICROSEC, usec_per_tick will be zero and lots of stuff will break.
 142  *     Similarly, if hz < 100 then hz / 100 == 0 and stuff will break.
 143  *
 144  * (2) If hz <= 1000, it should be both a multiple of 100 and a
 145  *      divisor of 1000.
 146  *
 147  * (3) If hz > 1000, it should be both a multiple of 1000 and a
 148  *      divisor of MICROSEC.
 149  *
 150  * Thus the only reasonable values of hz (i.e. the values that won't
 151  * cause roundoff error) are: 100, 200, 500, 1000, 2000, 4000, 5000,
 152  * 8000, 10000, 20000, 25000, 40000, 50000, 100000, 125000, 200000,
 153  * 250000, 500000, 1000000.  As of this writing (1996) a clock rate
 154  * of more than about 10 kHz seems utterly ridiculous, although
 155  * this observation will no doubt seem quaintly amusing one day.
 156  */
 157 #define HIRES_HZ_DEFAULT        1000
 158 
 159 int hz = HZ_DEFAULT;
 160 int hires_hz = HIRES_HZ_DEFAULT;
 161 
 162 int hires_tick = 0;
 163 int cpu_decay_factor = 10;      /* this is no longer tied to clock */
 164 int max_hres_adj;       /* maximum adjustment of hrtime per tick */
 165 int tick_per_msec;      /* clock ticks per millisecond (zero if hz < 1000) */
 166 
 167 /*
 168  * Milliseconds, Microseconds, and Nanoseconds per clock tick
 169  *
 170  * Note:
 171  *  msec_per_tick is zero if hz > 1000
 172  */
 173 int msec_per_tick;
 174 int usec_per_tick;
 175 int nsec_per_tick;
 176 
 177 /*
 178  * Time Resolution values. These are defined in condvar.h and initialized in
 179  * param_init(). Consumers of cv_reltimedwait() and cv_reltimedwait_sig()
 180  * need to specify how accurate the timeout argument should be through
 181  * one of these values. The intention is to allow the underlying implementation
 182  * to anticipate or defer the expiration of timeouts, preventing unnecessary
 183  * wakeups by batch processing similarly expiring events.
 184  */
 185 time_res_t time_res[TR_COUNT];
 186 
 187 /*
 188  * Setting "snooping" to a non-zero value will cause a deadman panic if
 189  * snoop_interval microseconds elapse without lbolt increasing.  The default
 190  * snoop_interval is 50 seconds.
 191  */
 192 #define SNOOP_INTERVAL_MIN      (MICROSEC)
 193 #define SNOOP_INTERVAL_DEFAULT  (50 * MICROSEC)
 194 
 195 int snooping = 0;
 196 uint_t snoop_interval = SNOOP_INTERVAL_DEFAULT;
 197 
 198 /*
 199  * Tables of initialization functions, called from main().
 200  */
 201 
 202 extern void system_taskq_init(void);
 203 extern void binit(void);
 204 extern void space_init(void);
 205 extern void dnlc_init(void);
 206 extern void vfsinit(void);
 207 extern void finit(void);
 208 extern void strinit(void);
 209 extern void flk_init(void);
 210 extern void ftrace_init(void);
 211 extern void softcall_init(void);
 212 extern void ttyinit(void);
 213 extern void schedctl_init(void);
 214 extern void deadman_init(void);
 215 extern void clock_timer_init(void);
 216 extern void clock_realtime_init(void);
 217 extern void clock_highres_init(void);
 218 extern void clock_tick_mp_init(void);
 219 extern void cu_init(void);
 220 extern void callout_mp_init(void);
 221 extern void cpu_seq_tbl_init(void);
 222 
 223 void    (*init_tbl[])(void) = {
 224         system_taskq_init,
 225         binit,
 226         space_init,
 227         dnlc_init,
 228         vfsinit,
 229         finit,
 230         strinit,
 231         serializer_init,
 232         softcall_init,
 233         ttyinit,
 234         as_init,
 235         pvn_init,
 236         anon_init,
 237         segvn_init,
 238         flk_init,
 239         cpu_seq_tbl_init,
 240         schedctl_init,
 241         fdb_init,
 242         deadman_init,
 243         clock_timer_init,
 244         clock_realtime_init,
 245         clock_highres_init,
 246         0
 247 };
 248 
 249 
 250 #if defined(__sparc)
 251         extern void siron_mp_init();
 252 #endif
 253 
 254 /*
 255  * Any per cpu resources should be initialized via
 256  * an entry in mp_init_tbl().
 257  */
 258 void    (*mp_init_tbl[])(void) = {
 259         ftrace_init,
 260         cyclic_mp_init,
 261 #if defined(__sparc)
 262         siron_mp_init,
 263 #endif
 264         clock_tick_mp_init,
 265         cu_init,
 266         callout_mp_init,
 267         0
 268 };
 269 
 270 int maxusers;           /* kitchen-sink knob for dynamic configuration */
 271 
 272 /*
 273  * pidmax -- highest pid value assigned by the system
 274  * Settable in /etc/system
 275  */
 276 int pidmax = DEFAULT_MAXPID;
 277 
 278 /*
 279  * jump_pid - if set, this value is where pid numbers should start
 280  * after the first few system pids (0-3) are used.  If 0, pids are
 281  * chosen in the usual way. This variable can be used to quickly
 282  * create large pids (by setting it to 100000, for example). pids
 283  * less than this value will never be chosen.
 284  */
 285 pid_t jump_pid = DEFAULT_JUMPPID;
 286 
 287 /*
 288  * autoup -- used in struct var for dynamic config of the age a delayed-write
 289  * buffer must be in seconds before bdflush will write it out.
 290  */
 291 #define DEFAULT_AUTOUP  30
 292 int autoup = DEFAULT_AUTOUP;
 293 
 294 /*
 295  * bufhwm -- tuneable variable for struct var for v_bufhwm.
 296  * high water mark for buffer cache mem usage in units of K bytes.
 297  *
 298  * bufhwm_pct -- ditto, but given in % of physmem.
 299  */
 300 int bufhwm = 0;
 301 int bufhwm_pct = 0;
 302 
 303 /*
 304  * Process table.
 305  */
 306 int maxpid;
 307 int max_nprocs;         /* set in param_init() */
 308 int maxuprc;            /* set in param_init() */
 309 int reserved_procs;
 310 int nthread = 1;
 311 
 312 /*
 313  * UFS tunables
 314  */
 315 int ufs_ninode;         /* declared here due to backwards compatibility */
 316 int ndquot;             /* declared here due to backwards compatibility */
 317 
 318 /*
 319  * Exec switch table. This is used by the generic exec module
 320  * to switch out to the desired executable type, based on the
 321  * magic number. The currently supported types are ELF, a.out
 322  * (both NMAGIC and ZMAGIC), interpreter (#!) files,
 323  * and Java executables.
 324  */
 325 /*
 326  * Magic numbers
 327  */
 328 short elfmagic = 0x7f45;
 329 short intpmagic = 0x2321;
 330 short jmagic = 0x504b;
 331 
 332 #if defined(__sparc)
 333 short aout_nmagic = NMAGIC;
 334 short aout_zmagic = ZMAGIC;
 335 short aout_omagic = OMAGIC;
 336 #endif
 337 short nomagic = 0;
 338 
 339 /*
 340  * Magic strings
 341  */
 342 #define ELF32MAGIC_STRING       "\x7f""ELF\x1"
 343 #define ELF64MAGIC_STRING       "\x7f""ELF\x2"
 344 #define INTPMAGIC_STRING        "#!"
 345 #define JAVAMAGIC_STRING        "PK\003\004"
 346 #define AOUT_OMAGIC_STRING      "\x1""\x07"     /* 0407 */
 347 #define AOUT_NMAGIC_STRING      "\x1""\x08"     /* 0410 */
 348 #define AOUT_ZMAGIC_STRING      "\x1""\x0b"     /* 0413 */
 349 #define NOMAGIC_STRING          ""
 350 
 351 #define SHBIN_CNTL(x)   ((x)&037)
 352 #define SHBINMAGIC_STRING {SHBIN_CNTL('k'), SHBIN_CNTL('s'), SHBIN_CNTL('h'), 0}
 353 #define SHBINMAGIC_LEN  4
 354 
 355 char elf32magicstr[] = ELF32MAGIC_STRING;
 356 char elf64magicstr[] = ELF64MAGIC_STRING;
 357 char intpmagicstr[] = INTPMAGIC_STRING;
 358 char shbinmagicstr[] = SHBINMAGIC_STRING;
 359 char javamagicstr[] = JAVAMAGIC_STRING;
 360 #if defined(__sparc)
 361 char aout_nmagicstr[] = AOUT_NMAGIC_STRING;
 362 char aout_zmagicstr[] = AOUT_ZMAGIC_STRING;
 363 char aout_omagicstr[] = AOUT_OMAGIC_STRING;
 364 #endif
 365 char nomagicstr[] = NOMAGIC_STRING;
 366 
 367 char *execswnames[] = {
 368         "elfexec",      /* Elf32 */
 369 #ifdef _LP64
 370         "elfexec",      /* Elf64 */
 371 #endif
 372         "intpexec",
 373         "shbinexec",
 374         "javaexec",
 375 #if defined(__sparc)
 376         "aoutexec",
 377         "aoutexec",
 378         "aoutexec",
 379 #endif
 380         NULL,
 381         NULL,
 382         NULL
 383 };
 384 
 385 struct execsw execsw[] = {
 386         { elf32magicstr, 0, 5, NULL, NULL, NULL },
 387 #ifdef _LP64
 388         { elf64magicstr, 0, 5, NULL, NULL, NULL },
 389 #endif
 390         { intpmagicstr, 0, 2, NULL, NULL, NULL },
 391         { shbinmagicstr, 0, SHBINMAGIC_LEN, NULL, NULL, NULL },
 392         { javamagicstr, 0, 4, NULL, NULL, NULL },
 393 #if defined(__sparc)
 394         { aout_zmagicstr, 2, 2, NULL, NULL, NULL },
 395         { aout_nmagicstr, 2, 2, NULL, NULL, NULL },
 396         { aout_omagicstr, 2, 2, NULL, NULL, NULL },
 397 #endif
 398         { nomagicstr, 0, 0, NULL, NULL, NULL },
 399         { nomagicstr, 0, 0, NULL, NULL, NULL },
 400         { nomagicstr, 0, 0, NULL, NULL, NULL },
 401         { nomagicstr, 0, 0, NULL, NULL, NULL }
 402 };
 403 int nexectype = sizeof (execsw) / sizeof (execsw[0]);   /* # of exec types */
 404 kmutex_t execsw_lock;   /* Used for allocation of execsw entries */
 405 
 406 /*
 407  * symbols added to make changing max-file-descriptors
 408  * simple via /etc/system
 409  */
 410 #define RLIM_FD_CUR 0x100
 411 #define RLIM_FD_MAX 0x10000
 412 
 413 uint_t rlim_fd_cur = RLIM_FD_CUR;
 414 uint_t rlim_fd_max = RLIM_FD_MAX;
 415 
 416 /*
 417  * (Default resource limits were formerly declared here, but are now provided by
 418  * the more general resource controls framework.)
 419  */
 420 
 421 /*
 422  * STREAMS tunables
 423  */
 424 int     nstrpush = 9;           /* maximum # of modules/drivers on a stream */
 425 ssize_t strctlsz = 1024;        /* maximum size of user-generated M_PROTO */
 426 ssize_t strmsgsz = 0x10000;     /* maximum size of user-generated M_DATA */
 427                                 /* for `strmsgsz', zero means unlimited */
 428 /*
 429  * Filesystem tunables
 430  */
 431 int     rstchown = 1;           /* POSIX_CHOWN_RESTRICTED is enabled */
 432 int     ngroups_max = NGROUPS_MAX_DEFAULT;
 433 
 434 /*
 435  * generic scheduling stuff
 436  *
 437  * Configurable parameters for RT and TS are in the respective
 438  * scheduling class modules.
 439  */
 440 
 441 pri_t maxclsyspri = MAXCLSYSPRI;
 442 pri_t minclsyspri = MINCLSYSPRI;
 443 char sys_name[] = "SYS";
 444 
 445 extern pri_t sys_init(id_t, int, classfuncs_t **);
 446 extern classfuncs_t sys_classfuncs;
 447 
 448 sclass_t sclass[] = {
 449         { "SYS",        sys_init,       &sys_classfuncs, STATIC_SCHED, 0 },
 450         { "",   NULL,   NULL,   NULL, 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 };
 460 
 461 int loaded_classes = 1;         /* for loaded classes */
 462 kmutex_t class_lock;            /* lock for class[] */
 463 
 464 int nclass = sizeof (sclass) / sizeof (sclass_t);
 465 char initcls[] = "TS";
 466 char *defaultclass = initcls;
 467 
 468 /*
 469  * Tunable system parameters.
 470  */
 471 
 472 /*
 473  * The integers tune_* are done this way so that the tune
 474  * data structure may be "tuned" if necessary from the /etc/system
 475  * file. The tune data structure is initialized in param_init();
 476  */
 477 
 478 tune_t tune;
 479 
 480 /*
 481  * If freemem < t_getpgslow, then start to steal pages from processes.
 482  */
 483 int tune_t_gpgslo = 25;
 484 
 485 /*
 486  * Rate at which fsflush is run, in seconds.
 487  */
 488 #define DEFAULT_TUNE_T_FSFLUSHR 1
 489 int tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
 490 
 491 /*
 492  * The minimum available resident (not swappable) memory to maintain
 493  * in order to avoid deadlock.  In pages.
 494  */
 495 int tune_t_minarmem = 25;
 496 
 497 /*
 498  * The minimum available swappable memory to maintain in order to avoid
 499  * deadlock.  In pages.
 500  */
 501 int tune_t_minasmem = 25;
 502 
 503 int tune_t_flckrec = 512;       /* max # of active frlocks */
 504 
 505 /*
 506  * Number of currently available pages that cannot be 'locked'
 507  * This is set in init_pages_pp_maximum, and must be initialized
 508  * to zero here to detect an override in /etc/system
 509  */
 510 pgcnt_t pages_pp_maximum = 0;
 511 
 512 int boothowto;                  /* boot flags passed to kernel */
 513 struct var v;                   /* System Configuration Information */
 514 
 515 /*
 516  * System Configuration Information
 517  */
 518 
 519 /*
 520  * The physical system's host identifier, expressed as a decimal string.
 521  * Code should only directly access this value when writing to it (setting the
 522  * physical system's host identifier).  Code that reads the physical system's
 523  * host identifier should use zone_get_hostid(NULL) instead.
 524  */
 525 char hw_serial[HW_HOSTID_LEN] = "0";
 526 
 527 #if defined(__sparc)
 528 
 529 /*
 530  * On sparc machines, read hw_serial from the firmware at boot time
 531  * and simply assert Oracle is the hardware provider.
 532  */
 533 char architecture[] = "sparcv9";
 534 char architecture_32[] = "sparc";
 535 char hw_provider[] = "Oracle Corporation";
 536 
 537 #elif defined(__i386)
 538 
 539 char architecture[] = "i386";
 540 char architecture_32[] = "i386";
 541 char hw_provider[SYS_NMLN] = "";
 542 
 543 #elif defined(__amd64)
 544 
 545 char architecture[] = "amd64";
 546 char architecture_32[] = "i386";
 547 char hw_provider[SYS_NMLN] = "";
 548 
 549 #else
 550 #error "unknown processor architecture"
 551 #endif
 552 
 553 char srpc_domain[SYS_NMLN] = "";
 554 char platform[SYS_NMLN] = "";   /* read from the devinfo root node */
 555 
 556 /* Initialize isa_list */
 557 char *isa_list = architecture;
 558 
 559 static pgcnt_t original_physmem = 0;
 560 
 561 #define MIN_DEFAULT_MAXUSERS    8u
 562 #define MAX_DEFAULT_MAXUSERS    2048u
 563 #define MAX_MAXUSERS            4096u
 564 
 565 void
 566 param_preset(void)
 567 {
 568         original_physmem = physmem;
 569 }
 570 
 571 void
 572 param_calc(int platform_max_nprocs)
 573 {
 574         /*
 575          * Default to about one "user" per megabyte, taking into
 576          * account both physical and virtual constraints.
 577          * Note: 2^20 is a meg; shifting right by (20 - PAGESHIFT)
 578          * converts pages to megs without integer overflow.
 579          */
 580 #if defined(__sparc)
 581         if (physmem > original_physmem) {
 582                 physmem = original_physmem;
 583                 cmn_err(CE_NOTE, "physmem limited to %ld", physmem);
 584         }
 585 #endif
 586         if (maxusers == 0) {
 587                 pgcnt_t physmegs = physmem >> (20 - PAGESHIFT);
 588                 pgcnt_t virtmegs = vmem_size(heap_arena, VMEM_FREE) >> 20;
 589                 maxusers = MIN(MAX(MIN(physmegs, virtmegs),
 590                     MIN_DEFAULT_MAXUSERS), MAX_DEFAULT_MAXUSERS);
 591         }
 592         if (maxusers > MAX_MAXUSERS) {
 593                 maxusers = MAX_MAXUSERS;
 594                 cmn_err(CE_NOTE, "maxusers limited to %d", MAX_MAXUSERS);
 595         }
 596 
 597 #ifdef DEBUG
 598         /*
 599          * The purpose of maxusers is to prevent memory overcommit.
 600          * DEBUG kernels take more space, so reduce maxusers a bit.
 601          */
 602         maxusers = (3 * maxusers) / 4;
 603 #endif
 604 
 605         /*
 606          * We need to dynamically change any variables now so that
 607          * the setting of maxusers and pidmax propagate to the other
 608          * variables that are dependent on them.
 609          */
 610         if (reserved_procs == 0)
 611                 reserved_procs = 5;
 612         if (pidmax < reserved_procs || pidmax > MAX_MAXPID)
 613                 maxpid = MAX_MAXPID;
 614         else
 615                 maxpid = pidmax;
 616 
 617         /*
 618          * This allows platform-dependent code to constrain the maximum
 619          * number of processes allowed in case there are e.g. VM limitations
 620          * with how many contexts are available.
 621          */
 622         if (max_nprocs == 0)
 623                 max_nprocs = (10 + 16 * maxusers);
 624         if (platform_max_nprocs > 0 && max_nprocs > platform_max_nprocs)
 625                 max_nprocs = platform_max_nprocs;
 626         if (max_nprocs > maxpid)
 627                 max_nprocs = maxpid;
 628 
 629         if (maxuprc == 0)
 630                 maxuprc = (max_nprocs - reserved_procs);
 631 }
 632 
 633 void
 634 param_init(void)
 635 {
 636         /*
 637          * Set each individual element of struct var v to be the
 638          * default value. This is done this way
 639          * so that a user can set the assigned integer value in the
 640          * /etc/system file *IF* tuning is needed.
 641          */
 642         v.v_proc = max_nprocs;  /* v_proc - max # of processes system wide */
 643         v.v_maxupttl = max_nprocs - reserved_procs;
 644         v.v_maxsyspri = (int)maxclsyspri;  /* max global pri for sysclass */
 645         v.v_maxup = MIN(maxuprc, v.v_maxupttl); /* max procs per user */
 646         v.v_autoup = autoup;    /* v_autoup - delay for delayed writes */
 647 
 648         /*
 649          * Set each individual element of struct tune to be the
 650          * default value. Each struct element This is done this way
 651          *  so that a user can set the assigned integer value in the
 652          * /etc/system file *IF* tuning is needed.
 653          */
 654         tune.t_gpgslo = tune_t_gpgslo;
 655         tune.t_fsflushr = tune_t_fsflushr;
 656         tune.t_minarmem = tune_t_minarmem;
 657         tune.t_minasmem = tune_t_minasmem;
 658         tune.t_flckrec = tune_t_flckrec;
 659 
 660         /*
 661          * Initialization for file descriptors to correct mistaken settings in
 662          * /etc/system.  Initialization of limits performed by resource control
 663          * system.
 664          */
 665         if (rlim_fd_cur > rlim_fd_max)
 666                 rlim_fd_cur = rlim_fd_max;
 667 
 668         /*
 669          * calculations needed if hz was set in /etc/system
 670          */
 671         if (hires_tick)
 672                 hz = hires_hz;
 673 
 674         tick_per_msec = hz / MILLISEC;
 675         msec_per_tick = MILLISEC / hz;
 676         usec_per_tick = MICROSEC / hz;
 677         nsec_per_tick = NANOSEC / hz;
 678         max_hres_adj = nsec_per_tick >> ADJ_SHIFT;
 679 
 680         /*
 681          * Consumers of relative timedwait functions must specify how accurately
 682          * the given timeout must expire. This is currently TR_CLOCK_TICK for
 683          * the vast majority of consumers, but nsec_per_tick becomes an
 684          * artificial value in a tickless world. Each caller of such routines
 685          * should re-evaluate their usage and specify the appropriate
 686          * resolution.
 687          */
 688         time_res[TR_NANOSEC] = NANOSEC / NANOSEC;
 689         time_res[TR_MICROSEC] = NANOSEC / MICROSEC;
 690         time_res[TR_MILLISEC] = NANOSEC / MILLISEC;
 691         time_res[TR_SEC] = NANOSEC / SEC;
 692         time_res[TR_CLOCK_TICK] = nsec_per_tick;
 693 }
 694 
 695 /*
 696  * Validate tuneable parameters following /etc/system processing,
 697  * but prior to param_init().
 698  */
 699 void
 700 param_check(void)
 701 {
 702 #if defined(__x86)
 703         if (physmem != original_physmem) {
 704                 cmn_err(CE_NOTE, "physmem cannot be modified to 0x%lx"
 705                     " via /etc/system. Please use eeprom(1M) instead.",
 706                     physmem);
 707                 physmem = original_physmem;
 708         }
 709 #endif
 710         if (ngroups_max < NGROUPS_UMIN)
 711                 ngroups_max = NGROUPS_UMIN;
 712         if (ngroups_max > NGROUPS_UMAX)
 713                 ngroups_max = NGROUPS_UMAX;
 714 
 715         /* If we have many groups then the ucred proto message also grows. */
 716         if (ngroups_max > NGROUPS_OLDMAX &&
 717             strctlsz < (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) + 1024) {
 718                 strctlsz = (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) +
 719                     1024;
 720         }
 721 
 722         if (autoup <= 0) {
 723                 autoup = DEFAULT_AUTOUP;
 724                 cmn_err(CE_WARN, "autoup <= 0; defaulting to %d", autoup);
 725         }
 726 
 727         if (tune_t_fsflushr <= 0) {
 728                 tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
 729                 cmn_err(CE_WARN, "tune_t_fsflushr <= 0; defaulting to %d",
 730                     tune_t_fsflushr);
 731         }
 732 
 733         if (jump_pid < 0 || jump_pid >= pidmax) {
 734                 jump_pid = 0;
 735                 cmn_err(CE_WARN, "jump_pid < 0 or >= pidmax; ignored");
 736         }
 737 
 738         if (snoop_interval < SNOOP_INTERVAL_MIN) {
 739                 snoop_interval = SNOOP_INTERVAL_DEFAULT;
 740                 cmn_err(CE_WARN, "snoop_interval < minimum (%d); defaulting"
 741                     " to %d", SNOOP_INTERVAL_MIN, SNOOP_INTERVAL_DEFAULT);
 742         }
 743 }