xref: /titanic_52/usr/src/uts/common/conf/param.c (revision b02e9a2d4d2071d770e5aa9ae8f83f2bbe1f2ced)
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  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
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 
69 #include <sys/vmem.h>
70 #include <sys/clock.h>
71 #include <sys/serializer.h>
72 
73 /*
74  * The following few lines describe generic things that must be compiled
75  * into the booted executable (unix) rather than genunix or any other
76  * module because they're required by crash dump readers, etc.
77  */
78 struct modctl modules;		/* head of linked list of modules */
79 char *default_path;		/* default module loading path */
80 struct swapinfo *swapinfo;	/* protected by the swapinfo_lock */
81 proc_t *practive;		/* active process list */
82 uint_t nproc;			/* current number of processes */
83 proc_t p0;			/* process 0 */
84 struct plock p0lock;		/* p0's p_lock */
85 klwp_t lwp0;			/* t0's lwp */
86 task_t *task0p;			/* task 0 */
87 kproject_t *proj0p;		/* location of project 0 */
88 
89 /*
90  * The following are "implementation architecture" dependent constants made
91  * available here in the form of initialized data for use by "implementation
92  * architecture" independent modules. See machparam.h.
93  */
94 const unsigned long	_pagesize	= (unsigned long)PAGESIZE;
95 const unsigned int	_pageshift	= (unsigned int)PAGESHIFT;
96 const unsigned long	_pageoffset	= (unsigned long)PAGEOFFSET;
97 /*
98  * XXX - This value pagemask has to be a 64bit size because
99  * large file support uses this mask on offsets which are 64 bit size.
100  * using unsigned leaves the higher 32 bits value as zero thus
101  * corrupting offset calculations in the file system and VM.
102  */
103 const u_longlong_t	_pagemask	= (u_longlong_t)PAGEMASK;
104 const unsigned long	_mmu_pagesize	= (unsigned long)MMU_PAGESIZE;
105 const unsigned int	_mmu_pageshift	= (unsigned int)MMU_PAGESHIFT;
106 const unsigned long	_mmu_pageoffset	= (unsigned long)MMU_PAGEOFFSET;
107 const unsigned long	_mmu_pagemask	= (unsigned long)MMU_PAGEMASK;
108 uintptr_t		_kernelbase	= (uintptr_t)KERNELBASE;
109 uintptr_t		_userlimit	= (uintptr_t)USERLIMIT;
110 uintptr_t		_userlimit32	= (uintptr_t)USERLIMIT32;
111 const uintptr_t		_argsbase	= (uintptr_t)ARGSBASE;
112 const unsigned int	_diskrpm	= (unsigned int)DISKRPM;
113 const unsigned long	_pgthresh	= (unsigned long)PGTHRESH;
114 const unsigned int	_maxslp		= (unsigned int)MAXSLP;
115 const unsigned long	_maxhandspreadpages = (unsigned long)MAXHANDSPREADPAGES;
116 const int		_ncpu 		= (int)NCPU;
117 const unsigned long	_defaultstksz	= (unsigned long)DEFAULTSTKSZ;
118 const unsigned int	_nbpg		= (unsigned int)MMU_PAGESIZE;
119 
120 /*
121  * System parameter formulae.
122  *
123  * This file is copied into each directory where we compile
124  * the kernel; it should be modified there to suit local taste
125  * if necessary.
126  */
127 
128 /*
129  * Default hz is 100, but if we set hires_tick we get higher resolution
130  * clock behavior (currently defined to be 1000 hz).  Higher values seem
131  * to work, but are not supported.
132  *
133  * If we do decide to play with higher values, remember that hz should
134  * satisfy the following constraints to avoid integer round-off problems:
135  *
136  * (1) hz should be in the range 100 <= hz <= MICROSEC.  If hz exceeds
137  *     MICROSEC, usec_per_tick will be zero and lots of stuff will break.
138  *     Similarly, if hz < 100 then hz / 100 == 0 and stuff will break.
139  *
140  * (2) If hz <= 1000, it should be both a multiple of 100 and a
141  *	divisor of 1000.
142  *
143  * (3) If hz > 1000, it should be both a multiple of 1000 and a
144  *	divisor of MICROSEC.
145  *
146  * Thus the only reasonable values of hz (i.e. the values that won't
147  * cause roundoff error) are: 100, 200, 500, 1000, 2000, 4000, 5000,
148  * 8000, 10000, 20000, 25000, 40000, 50000, 100000, 125000, 200000,
149  * 250000, 500000, 1000000.  As of this writing (1996) a clock rate
150  * of more than about 10 kHz seems utterly ridiculous, although
151  * this observation will no doubt seem quaintly amusing one day.
152  */
153 int hz = 100;
154 int hires_hz = 1000;
155 int hires_tick = 0;
156 int cpu_decay_factor = 10;	/* this is no longer tied to clock */
157 int tick_per_msec;	/* clock ticks per millisecond (zero if hz < 1000) */
158 int msec_per_tick;	/* millseconds per clock tick (zero if hz > 1000) */
159 int usec_per_tick;	/* microseconds per clock tick */
160 int nsec_per_tick;	/* nanoseconds per clock tick */
161 int max_hres_adj;	/* maximum adjustment of hrtime per tick */
162 
163 /*
164  * Setting "snooping" to a non-zero value will cause a deadman panic if
165  * snoop_interval microseconds elapse without lbolt increasing.  The default
166  * snoop_interval is 50 seconds.
167  */
168 #define	SNOOP_INTERVAL_MIN	(MICROSEC)
169 #define	SNOOP_INTERVAL_DEFAULT	(50 * MICROSEC)
170 
171 int snooping = 0;
172 uint_t snoop_interval = SNOOP_INTERVAL_DEFAULT;
173 
174 /*
175  * Tables of initialization functions, called from main().
176  */
177 
178 extern void system_taskq_init(void);
179 extern void binit(void);
180 extern void space_init(void);
181 extern void dnlc_init(void);
182 extern void vfsinit(void);
183 extern void finit(void);
184 extern void strinit(void);
185 extern void flk_init(void);
186 extern void ftrace_init(void);
187 extern void softcall_init(void);
188 extern void ttyinit(void);
189 extern void schedctl_init(void);
190 extern void deadman_init(void);
191 extern void clock_timer_init(void);
192 extern void clock_realtime_init(void);
193 extern void clock_highres_init(void);
194 extern void pg_init(void);
195 extern void pg_cmt_class_init(void);
196 extern void pg_cpu0_init(void);
197 
198 void	(*init_tbl[])(void) = {
199 	system_taskq_init,
200 	binit,
201 	space_init,
202 	dnlc_init,
203 	vfsinit,
204 	finit,
205 	strinit,
206 	serializer_init,
207 	softcall_init,
208 	ttyinit,
209 	as_init,
210 	pvn_init,
211 	anon_init,
212 	segvn_init,
213 	flk_init,
214 	pg_init,
215 	pg_cmt_class_init,
216 	pg_cpu0_init,
217 	schedctl_init,
218 	fdb_init,
219 	deadman_init,
220 	clock_timer_init,
221 	clock_realtime_init,
222 	clock_highres_init,
223 	0
224 };
225 
226 
227 #if defined(__sparc)
228 	extern void siron_mp_init();
229 #endif
230 
231 /*
232  * Any per cpu resources should be initialized via
233  * an entry in mp_init_tbl().
234  */
235 void	(*mp_init_tbl[])(void) = {
236 	ftrace_init,
237 	cyclic_mp_init,
238 #if defined(__sparc)
239 	siron_mp_init,
240 #endif
241 	0
242 };
243 
244 int maxusers;		/* kitchen-sink knob for dynamic configuration */
245 
246 /*
247  * pidmax -- highest pid value assigned by the system
248  * Settable in /etc/system
249  */
250 int pidmax = DEFAULT_MAXPID;
251 
252 /*
253  * jump_pid - if set, this value is where pid numbers should start
254  * after the first few system pids (0-3) are used.  If 0, pids are
255  * chosen in the usual way. This variable can be used to quickly
256  * create large pids (by setting it to 100000, for example). pids
257  * less than this value will never be chosen.
258  */
259 pid_t jump_pid = DEFAULT_JUMPPID;
260 
261 /*
262  * autoup -- used in struct var for dynamic config of the age a delayed-write
263  * buffer must be in seconds before bdflush will write it out.
264  */
265 #define	DEFAULT_AUTOUP	30
266 int autoup = DEFAULT_AUTOUP;
267 
268 /*
269  * bufhwm -- tuneable variable for struct var for v_bufhwm.
270  * high water mark for buffer cache mem usage in units of K bytes.
271  *
272  * bufhwm_pct -- ditto, but given in % of physmem.
273  */
274 int bufhwm = 0;
275 int bufhwm_pct = 0;
276 
277 /*
278  * Process table.
279  */
280 int maxpid;
281 int max_nprocs;		/* set in param_init() */
282 int maxuprc;		/* set in param_init() */
283 int reserved_procs;
284 int nthread = 1;
285 
286 /*
287  * UFS tunables
288  */
289 int ufs_ninode;		/* declared here due to backwards compatibility */
290 int ndquot;		/* declared here due to backwards compatibility */
291 
292 /*
293  * Exec switch table. This is used by the generic exec module
294  * to switch out to the desired executable type, based on the
295  * magic number. The currently supported types are ELF, a.out
296  * (both NMAGIC and ZMAGIC), interpreter (#!) files,
297  * and Java executables.
298  */
299 /*
300  * Magic numbers
301  */
302 short elfmagic = 0x7f45;
303 short intpmagic = 0x2321;
304 short jmagic = 0x504b;
305 
306 #if defined(__sparc)
307 short aout_nmagic = NMAGIC;
308 short aout_zmagic = ZMAGIC;
309 short aout_omagic = OMAGIC;
310 #endif
311 short nomagic = 0;
312 
313 /*
314  * Magic strings
315  */
316 #define	ELF32MAGIC_STRING	"\x7f""ELF\x1"
317 #define	ELF64MAGIC_STRING	"\x7f""ELF\x2"
318 #define	INTPMAGIC_STRING	"#!"
319 #define	JAVAMAGIC_STRING	"PK\003\004"
320 #define	AOUT_OMAGIC_STRING	"\x1""\x07"	/* 0407 */
321 #define	AOUT_NMAGIC_STRING	"\x1""\x08"	/* 0410 */
322 #define	AOUT_ZMAGIC_STRING	"\x1""\x0b"	/* 0413 */
323 #define	NOMAGIC_STRING		""
324 
325 char elf32magicstr[] = ELF32MAGIC_STRING;
326 char elf64magicstr[] = ELF64MAGIC_STRING;
327 char intpmagicstr[] = INTPMAGIC_STRING;
328 char javamagicstr[] = JAVAMAGIC_STRING;
329 #if defined(__sparc)
330 char aout_nmagicstr[] = AOUT_NMAGIC_STRING;
331 char aout_zmagicstr[] = AOUT_ZMAGIC_STRING;
332 char aout_omagicstr[] = AOUT_OMAGIC_STRING;
333 #endif
334 char nomagicstr[] = NOMAGIC_STRING;
335 
336 char *execswnames[] = {
337 	"elfexec",	/* Elf32 */
338 #ifdef _LP64
339 	"elfexec",	/* Elf64 */
340 #endif
341 	"intpexec",
342 	"javaexec",
343 #if defined(__sparc)
344 	"aoutexec",
345 	"aoutexec",
346 	"aoutexec",
347 #endif
348 	NULL,
349 	NULL,
350 	NULL
351 };
352 
353 struct execsw execsw[] = {
354 	{ elf32magicstr, 0, 5, NULL, NULL, NULL },
355 #ifdef _LP64
356 	{ elf64magicstr, 0, 5, NULL, NULL, NULL },
357 #endif
358 	{ intpmagicstr, 0, 2, NULL, NULL, NULL },
359 	{ javamagicstr, 0, 4, NULL, NULL, NULL },
360 #if defined(__sparc)
361 	{ aout_zmagicstr, 2, 2, NULL, NULL, NULL },
362 	{ aout_nmagicstr, 2, 2, NULL, NULL, NULL },
363 	{ aout_omagicstr, 2, 2, NULL, NULL, NULL },
364 #endif
365 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
366 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
367 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
368 	{ nomagicstr, 0, 0, NULL, NULL, NULL }
369 };
370 int nexectype = sizeof (execsw) / sizeof (execsw[0]);	/* # of exec types */
371 kmutex_t execsw_lock;	/* Used for allocation of execsw entries */
372 
373 /*
374  * symbols added to make changing max-file-descriptors
375  * simple via /etc/system
376  */
377 #define	RLIM_FD_CUR 0x100
378 #define	RLIM_FD_MAX 0x10000
379 
380 uint_t rlim_fd_cur = RLIM_FD_CUR;
381 uint_t rlim_fd_max = RLIM_FD_MAX;
382 
383 /*
384  * (Default resource limits were formerly declared here, but are now provided by
385  * the more general resource controls framework.)
386  */
387 
388 /*
389  * STREAMS tunables
390  */
391 int	nstrpush = 9;		/* maximum # of modules/drivers on a stream */
392 ssize_t	strctlsz = 1024;	/* maximum size of user-generated M_PROTO */
393 ssize_t	strmsgsz = 0x10000;	/* maximum size of user-generated M_DATA */
394 				/* for `strmsgsz', zero means unlimited */
395 /*
396  * Filesystem tunables
397  */
398 int	rstchown = 1;		/* POSIX_CHOWN_RESTRICTED is enabled */
399 int	ngroups_max = NGROUPS_MAX_DEFAULT;
400 
401 /*
402  * generic scheduling stuff
403  *
404  * Configurable parameters for RT and TS are in the respective
405  * scheduling class modules.
406  */
407 
408 pri_t maxclsyspri = MAXCLSYSPRI;
409 pri_t minclsyspri = MINCLSYSPRI;
410 char sys_name[] = "SYS";
411 
412 extern pri_t sys_init();
413 extern classfuncs_t sys_classfuncs;
414 
415 sclass_t sclass[] = {
416 	{ "SYS",	sys_init,	&sys_classfuncs, STATIC_SCHED, 0 },
417 	{ "",	NULL,	NULL,	NULL, 0 },
418 	{ "",	NULL,	NULL,	NULL, 0 },
419 	{ "",	NULL,	NULL,	NULL, 0 },
420 	{ "",	NULL,	NULL,	NULL, 0 },
421 	{ "",	NULL,	NULL,	NULL, 0 },
422 	{ "",	NULL,	NULL,	NULL, 0 },
423 	{ "",	NULL,	NULL,	NULL, 0 },
424 	{ "",	NULL,	NULL,	NULL, 0 },
425 	{ "",	NULL,	NULL,	NULL, 0 }
426 };
427 
428 int loaded_classes = 1;		/* for loaded classes */
429 kmutex_t class_lock;		/* lock for class[] */
430 
431 int nclass = sizeof (sclass) / sizeof (sclass_t);
432 char initcls[] = "TS";
433 char *defaultclass = initcls;
434 
435 /*
436  * Tunable system parameters.
437  */
438 
439 /*
440  * The integers tune_* are done this way so that the tune
441  * data structure may be "tuned" if necessary from the /etc/system
442  * file. The tune data structure is initialized in param_init();
443  */
444 
445 tune_t tune;
446 
447 /*
448  * If freemem < t_getpgslow, then start to steal pages from processes.
449  */
450 int tune_t_gpgslo = 25;
451 
452 /*
453  * Rate at which fsflush is run, in seconds.
454  */
455 #define	DEFAULT_TUNE_T_FSFLUSHR	1
456 int tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
457 
458 /*
459  * The minimum available resident (not swappable) memory to maintain
460  * in order to avoid deadlock.  In pages.
461  */
462 int tune_t_minarmem = 25;
463 
464 /*
465  * The minimum available swappable memory to maintain in order to avoid
466  * deadlock.  In pages.
467  */
468 int tune_t_minasmem = 25;
469 
470 int tune_t_flckrec = 512;	/* max # of active frlocks */
471 
472 /*
473  * Number of currently available pages that cannot be 'locked'
474  * This is set in init_pages_pp_maximum, and must be initialized
475  * to zero here to detect an override in /etc/system
476  */
477 pgcnt_t pages_pp_maximum = 0;
478 
479 int boothowto;			/* boot flags passed to kernel */
480 struct var v;			/* System Configuration Information */
481 
482 /*
483  * System Configuration Information
484  */
485 
486 #if defined(__sparc)
487 
488 /*
489  * On sparc machines, read hw_serial from the firmware at boot time
490  * and simply assert Sun is the hardware provider.  Hmm.
491  */
492 char architecture[] = "sparcv9";
493 char architecture_32[] = "sparc";
494 char hw_serial[11];
495 char hw_provider[] = "Sun_Microsystems";
496 
497 #elif defined(__i386)
498 
499 /*
500  * On x86 machines, read hw_serial, hw_provider and srpc_domain from
501  * /etc/bootrc at boot time.
502  */
503 char architecture[] = "i386";
504 char architecture_32[] = "i386";
505 char hw_serial[11] = "0";
506 char hw_provider[SYS_NMLN] = "";
507 
508 #elif defined(__amd64)
509 
510 /*
511  * On amd64 machines, read hw_serial, hw_provider and srpc_domain from
512  * /etc/bootrc at boot time.
513  */
514 char architecture[] = "amd64";
515 char architecture_32[] = "i386";
516 char hw_serial[11] = "0";
517 char hw_provider[SYS_NMLN] = "";
518 
519 #else
520 #error "unknown processor architecture"
521 #endif
522 
523 char srpc_domain[SYS_NMLN] = "";
524 char platform[SYS_NMLN] = "";	/* read from the devinfo root node */
525 
526 /* Initialize isa_list */
527 char *isa_list = architecture;
528 
529 static pgcnt_t original_physmem = 0;
530 
531 #define	MIN_DEFAULT_MAXUSERS	8u
532 #define	MAX_DEFAULT_MAXUSERS	2048u
533 #define	MAX_MAXUSERS		4096u
534 
535 void
536 param_preset(void)
537 {
538 	original_physmem = physmem;
539 }
540 
541 void
542 param_calc(int platform_max_nprocs)
543 {
544 	/*
545 	 * Default to about one "user" per megabyte, taking into
546 	 * account both physical and virtual constraints.
547 	 * Note: 2^20 is a meg; shifting right by (20 - PAGESHIFT)
548 	 * converts pages to megs without integer overflow.
549 	 */
550 #if defined(__sparc)
551 	if (physmem > original_physmem) {
552 		physmem = original_physmem;
553 		cmn_err(CE_NOTE, "physmem limited to %ld", physmem);
554 	}
555 #endif
556 	if (maxusers == 0) {
557 		pgcnt_t physmegs = physmem >> (20 - PAGESHIFT);
558 		pgcnt_t virtmegs = vmem_size(heap_arena, VMEM_FREE) >> 20;
559 		maxusers = MIN(MAX(MIN(physmegs, virtmegs),
560 		    MIN_DEFAULT_MAXUSERS), MAX_DEFAULT_MAXUSERS);
561 	}
562 	if (maxusers > MAX_MAXUSERS) {
563 		maxusers = MAX_MAXUSERS;
564 		cmn_err(CE_NOTE, "maxusers limited to %d", MAX_MAXUSERS);
565 	}
566 
567 	if (ngroups_max > NGROUPS_MAX_DEFAULT)
568 		cmn_err(CE_WARN, "ngroups_max of %d > %d, NFS AUTH_SYS will"
569 		    " not work properly", ngroups_max, NGROUPS_MAX_DEFAULT);
570 
571 #ifdef DEBUG
572 	/*
573 	 * The purpose of maxusers is to prevent memory overcommit.
574 	 * DEBUG kernels take more space, so reduce maxusers a bit.
575 	 */
576 	maxusers = (3 * maxusers) / 4;
577 #endif
578 
579 	/*
580 	 * We need to dynamically change any variables now so that
581 	 * the setting of maxusers and pidmax propagate to the other
582 	 * variables that are dependent on them.
583 	 */
584 	if (reserved_procs == 0)
585 		reserved_procs = 5;
586 	if (pidmax < reserved_procs || pidmax > MAX_MAXPID)
587 		maxpid = MAX_MAXPID;
588 	else
589 		maxpid = pidmax;
590 
591 	/*
592 	 * This allows platform-dependent code to constrain the maximum
593 	 * number of processes allowed in case there are e.g. VM limitations
594 	 * with how many contexts are available.
595 	 */
596 	if (max_nprocs == 0)
597 		max_nprocs = (10 + 16 * maxusers);
598 	if (platform_max_nprocs > 0 && max_nprocs > platform_max_nprocs)
599 		max_nprocs = platform_max_nprocs;
600 	if (max_nprocs > maxpid)
601 		max_nprocs = maxpid;
602 
603 	if (maxuprc == 0)
604 		maxuprc = (max_nprocs - reserved_procs);
605 }
606 
607 void
608 param_init(void)
609 {
610 	/*
611 	 * Set each individual element of struct var v to be the
612 	 * default value. This is done this way
613 	 * so that a user can set the assigned integer value in the
614 	 * /etc/system file *IF* tuning is needed.
615 	 */
616 	v.v_proc = max_nprocs;	/* v_proc - max # of processes system wide */
617 	v.v_maxupttl = max_nprocs - reserved_procs;
618 	v.v_maxsyspri = (int)maxclsyspri;  /* max global pri for sysclass */
619 	v.v_maxup = MIN(maxuprc, v.v_maxupttl); /* max procs per user */
620 	v.v_autoup = autoup;	/* v_autoup - delay for delayed writes */
621 
622 	/*
623 	 * Set each individual element of struct tune to be the
624 	 * default value. Each struct element This is done this way
625 	 *  so that a user can set the assigned integer value in the
626 	 * /etc/system file *IF* tuning is needed.
627 	 */
628 	tune.t_gpgslo = tune_t_gpgslo;
629 	tune.t_fsflushr = tune_t_fsflushr;
630 	tune.t_minarmem = tune_t_minarmem;
631 	tune.t_minasmem = tune_t_minasmem;
632 	tune.t_flckrec = tune_t_flckrec;
633 
634 	/*
635 	 * Initialization for file descriptors to correct mistaken settings in
636 	 * /etc/system.  Initialization of limits performed by resource control
637 	 * system.
638 	 */
639 	if (rlim_fd_cur > rlim_fd_max)
640 		rlim_fd_cur = rlim_fd_max;
641 
642 	/*
643 	 * calculations needed if hz was set in /etc/system
644 	 */
645 	if (hires_tick)
646 		hz = hires_hz;
647 
648 	tick_per_msec = hz / MILLISEC;
649 	msec_per_tick = MILLISEC / hz;
650 	usec_per_tick = MICROSEC / hz;
651 	nsec_per_tick = NANOSEC / hz;
652 	max_hres_adj = nsec_per_tick >> ADJ_SHIFT;
653 }
654 
655 /*
656  * Validate tuneable parameters following /etc/system processing,
657  * but prior to param_init().
658  */
659 void
660 param_check(void)
661 {
662 #if defined(__x86)
663 	if (physmem != original_physmem) {
664 		cmn_err(CE_NOTE, "physmem cannot be modified to 0x%lx"
665 		    " via /etc/system. Please use eeprom(1M) instead.",
666 		    physmem);
667 		physmem = original_physmem;
668 	}
669 #endif
670 	if (ngroups_max < NGROUPS_UMIN || ngroups_max > NGROUPS_UMAX)
671 		ngroups_max = NGROUPS_MAX_DEFAULT;
672 
673 	if (autoup <= 0) {
674 		autoup = DEFAULT_AUTOUP;
675 		cmn_err(CE_WARN, "autoup <= 0; defaulting to %d", autoup);
676 	}
677 
678 	if (tune_t_fsflushr <= 0) {
679 		tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
680 		cmn_err(CE_WARN, "tune_t_fsflushr <= 0; defaulting to %d",
681 		    tune_t_fsflushr);
682 	}
683 
684 	if (jump_pid < 0 || jump_pid >= pidmax) {
685 		jump_pid = 0;
686 		cmn_err(CE_WARN, "jump_pid < 0 or >= pidmax; ignored");
687 	}
688 
689 	if (snoop_interval < SNOOP_INTERVAL_MIN) {
690 		snoop_interval = SNOOP_INTERVAL_DEFAULT;
691 		cmn_err(CE_WARN, "snoop_interval < minimum (%d); defaulting"
692 		    " to %d", SNOOP_INTERVAL_MIN, SNOOP_INTERVAL_DEFAULT);
693 	}
694 }
695