xref: /illumos-gate/usr/src/uts/common/conf/param.c (revision 2a898b17c54fe53254413d8d4cac0de440289b59)
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 proc.max-file-descriptor
408  * simple via /etc/system
409  */
410 #define	RLIM_FD_CUR 0x10000
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 }
744