xref: /titanic_52/usr/src/uts/common/conf/param.c (revision f79b63829052fcaae660db7f78ce17efd13e15bc)
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 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/time.h>
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/signal.h>
31 #include <sys/sysmacros.h>
32 #include <sys/cmn_err.h>
33 #include <sys/user.h>
34 #include <sys/proc.h>
35 #include <sys/task.h>
36 #include <sys/project.h>
37 #include <sys/klwp.h>
38 #include <sys/vnode.h>
39 #include <sys/file.h>
40 #include <sys/fcntl.h>
41 #include <sys/flock.h>
42 #include <sys/var.h>
43 #include <sys/stream.h>
44 #include <sys/strsubr.h>
45 #include <sys/conf.h>
46 #include <sys/class.h>
47 #include <sys/ts.h>
48 #include <sys/rt.h>
49 #include <sys/exec.h>
50 #include <sys/exechdr.h>
51 #include <sys/buf.h>
52 #include <sys/resource.h>
53 #include <vm/seg.h>
54 #include <vm/pvn.h>
55 #include <vm/seg_kmem.h>
56 #include <sys/vmparam.h>
57 #include <sys/machparam.h>
58 #include <sys/utsname.h>
59 #include <sys/kmem.h>
60 #include <sys/stack.h>
61 #include <sys/modctl.h>
62 #include <sys/fdbuffer.h>
63 #include <sys/cyclic_impl.h>
64 #include <sys/disp.h>
65 #include <sys/tuneable.h>
66 #include <sys/systeminfo.h>
67 
68 #include <sys/vmem.h>
69 #include <sys/clock.h>
70 #include <sys/clock_impl.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 #define	HIRES_HZ_DEFAULT	1000
154 
155 int hz = HZ_DEFAULT;
156 int hires_hz = HIRES_HZ_DEFAULT;
157 
158 int hires_tick = 0;
159 int cpu_decay_factor = 10;	/* this is no longer tied to clock */
160 int max_hres_adj;	/* maximum adjustment of hrtime per tick */
161 int tick_per_msec;	/* clock ticks per millisecond (zero if hz < 1000) */
162 
163 /*
164  * Milliseconds, Microseconds, and Nanoseconds per clock tick
165  *
166  * Note:
167  *  msec_per_tick is zero if hz > 1000
168  */
169 int msec_per_tick;
170 int usec_per_tick;
171 int nsec_per_tick;
172 
173 /*
174  * Time Resolution values. These are defined in condvar.h and initialized in
175  * param_init(). Consumers of cv_reltimedwait() and cv_reltimedwait_sig()
176  * need to specify how accurate the timeout argument should be through
177  * one of these values. The intention is to allow the underlying implementation
178  * to anticipate or defer the expiration of timeouts, preventing unnecessary
179  * wakeups by batch processing similarly expiring events.
180  */
181 time_res_t time_res[TR_COUNT];
182 
183 /*
184  * Setting "snooping" to a non-zero value will cause a deadman panic if
185  * snoop_interval microseconds elapse without lbolt increasing.  The default
186  * snoop_interval is 50 seconds.
187  */
188 #define	SNOOP_INTERVAL_MIN	(MICROSEC)
189 #define	SNOOP_INTERVAL_DEFAULT	(50 * MICROSEC)
190 
191 int snooping = 0;
192 uint_t snoop_interval = SNOOP_INTERVAL_DEFAULT;
193 
194 /*
195  * Tables of initialization functions, called from main().
196  */
197 
198 extern void system_taskq_init(void);
199 extern void binit(void);
200 extern void space_init(void);
201 extern void dnlc_init(void);
202 extern void vfsinit(void);
203 extern void finit(void);
204 extern void strinit(void);
205 extern void flk_init(void);
206 extern void ftrace_init(void);
207 extern void softcall_init(void);
208 extern void ttyinit(void);
209 extern void schedctl_init(void);
210 extern void deadman_init(void);
211 extern void clock_timer_init(void);
212 extern void clock_realtime_init(void);
213 extern void clock_highres_init(void);
214 extern void clock_tick_mp_init(void);
215 extern void cu_init(void);
216 extern void callout_mp_init(void);
217 extern void cpu_seq_tbl_init(void);
218 
219 void	(*init_tbl[])(void) = {
220 	system_taskq_init,
221 	binit,
222 	space_init,
223 	dnlc_init,
224 	vfsinit,
225 	finit,
226 	strinit,
227 	serializer_init,
228 	softcall_init,
229 	ttyinit,
230 	as_init,
231 	pvn_init,
232 	anon_init,
233 	segvn_init,
234 	flk_init,
235 	cpu_seq_tbl_init,
236 	schedctl_init,
237 	fdb_init,
238 	deadman_init,
239 	clock_timer_init,
240 	clock_realtime_init,
241 	clock_highres_init,
242 	0
243 };
244 
245 
246 #if defined(__sparc)
247 	extern void siron_mp_init();
248 #endif
249 
250 /*
251  * Any per cpu resources should be initialized via
252  * an entry in mp_init_tbl().
253  */
254 void	(*mp_init_tbl[])(void) = {
255 	ftrace_init,
256 	cyclic_mp_init,
257 #if defined(__sparc)
258 	siron_mp_init,
259 #endif
260 	clock_tick_mp_init,
261 	cu_init,
262 	callout_mp_init,
263 	0
264 };
265 
266 int maxusers;		/* kitchen-sink knob for dynamic configuration */
267 
268 /*
269  * pidmax -- highest pid value assigned by the system
270  * Settable in /etc/system
271  */
272 int pidmax = DEFAULT_MAXPID;
273 
274 /*
275  * jump_pid - if set, this value is where pid numbers should start
276  * after the first few system pids (0-3) are used.  If 0, pids are
277  * chosen in the usual way. This variable can be used to quickly
278  * create large pids (by setting it to 100000, for example). pids
279  * less than this value will never be chosen.
280  */
281 pid_t jump_pid = DEFAULT_JUMPPID;
282 
283 /*
284  * autoup -- used in struct var for dynamic config of the age a delayed-write
285  * buffer must be in seconds before bdflush will write it out.
286  */
287 #define	DEFAULT_AUTOUP	30
288 int autoup = DEFAULT_AUTOUP;
289 
290 /*
291  * bufhwm -- tuneable variable for struct var for v_bufhwm.
292  * high water mark for buffer cache mem usage in units of K bytes.
293  *
294  * bufhwm_pct -- ditto, but given in % of physmem.
295  */
296 int bufhwm = 0;
297 int bufhwm_pct = 0;
298 
299 /*
300  * Process table.
301  */
302 int maxpid;
303 int max_nprocs;		/* set in param_init() */
304 int maxuprc;		/* set in param_init() */
305 int reserved_procs;
306 int nthread = 1;
307 
308 /*
309  * UFS tunables
310  */
311 int ufs_ninode;		/* declared here due to backwards compatibility */
312 int ndquot;		/* declared here due to backwards compatibility */
313 
314 /*
315  * Exec switch table. This is used by the generic exec module
316  * to switch out to the desired executable type, based on the
317  * magic number. The currently supported types are ELF, a.out
318  * (both NMAGIC and ZMAGIC), interpreter (#!) files,
319  * and Java executables.
320  */
321 /*
322  * Magic numbers
323  */
324 short elfmagic = 0x7f45;
325 short intpmagic = 0x2321;
326 short jmagic = 0x504b;
327 
328 #if defined(__sparc)
329 short aout_nmagic = NMAGIC;
330 short aout_zmagic = ZMAGIC;
331 short aout_omagic = OMAGIC;
332 #endif
333 short nomagic = 0;
334 
335 /*
336  * Magic strings
337  */
338 #define	ELF32MAGIC_STRING	"\x7f""ELF\x1"
339 #define	ELF64MAGIC_STRING	"\x7f""ELF\x2"
340 #define	INTPMAGIC_STRING	"#!"
341 #define	JAVAMAGIC_STRING	"PK\003\004"
342 #define	AOUT_OMAGIC_STRING	"\x1""\x07"	/* 0407 */
343 #define	AOUT_NMAGIC_STRING	"\x1""\x08"	/* 0410 */
344 #define	AOUT_ZMAGIC_STRING	"\x1""\x0b"	/* 0413 */
345 #define	NOMAGIC_STRING		""
346 
347 #define	SHBIN_CNTL(x)	((x)&037)
348 #define	SHBINMAGIC_STRING {SHBIN_CNTL('k'), SHBIN_CNTL('s'), SHBIN_CNTL('h'), 0}
349 #define	SHBINMAGIC_LEN	4
350 
351 char elf32magicstr[] = ELF32MAGIC_STRING;
352 char elf64magicstr[] = ELF64MAGIC_STRING;
353 char intpmagicstr[] = INTPMAGIC_STRING;
354 char shbinmagicstr[] = SHBINMAGIC_STRING;
355 char javamagicstr[] = JAVAMAGIC_STRING;
356 #if defined(__sparc)
357 char aout_nmagicstr[] = AOUT_NMAGIC_STRING;
358 char aout_zmagicstr[] = AOUT_ZMAGIC_STRING;
359 char aout_omagicstr[] = AOUT_OMAGIC_STRING;
360 #endif
361 char nomagicstr[] = NOMAGIC_STRING;
362 
363 char *execswnames[] = {
364 	"elfexec",	/* Elf32 */
365 #ifdef _LP64
366 	"elfexec",	/* Elf64 */
367 #endif
368 	"intpexec",
369 	"shbinexec",
370 	"javaexec",
371 #if defined(__sparc)
372 	"aoutexec",
373 	"aoutexec",
374 	"aoutexec",
375 #endif
376 	NULL,
377 	NULL,
378 	NULL
379 };
380 
381 struct execsw execsw[] = {
382 	{ elf32magicstr, 0, 5, NULL, NULL, NULL },
383 #ifdef _LP64
384 	{ elf64magicstr, 0, 5, NULL, NULL, NULL },
385 #endif
386 	{ intpmagicstr, 0, 2, NULL, NULL, NULL },
387 	{ shbinmagicstr, 0, SHBINMAGIC_LEN, NULL, NULL, NULL },
388 	{ javamagicstr, 0, 4, NULL, NULL, NULL },
389 #if defined(__sparc)
390 	{ aout_zmagicstr, 2, 2, NULL, NULL, NULL },
391 	{ aout_nmagicstr, 2, 2, NULL, NULL, NULL },
392 	{ aout_omagicstr, 2, 2, NULL, NULL, NULL },
393 #endif
394 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
395 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
396 	{ nomagicstr, 0, 0, NULL, NULL, NULL },
397 	{ nomagicstr, 0, 0, NULL, NULL, NULL }
398 };
399 int nexectype = sizeof (execsw) / sizeof (execsw[0]);	/* # of exec types */
400 kmutex_t execsw_lock;	/* Used for allocation of execsw entries */
401 
402 /*
403  * symbols added to make changing max-file-descriptors
404  * simple via /etc/system
405  */
406 #define	RLIM_FD_CUR 0x100
407 #define	RLIM_FD_MAX 0x10000
408 
409 uint_t rlim_fd_cur = RLIM_FD_CUR;
410 uint_t rlim_fd_max = RLIM_FD_MAX;
411 
412 /*
413  * (Default resource limits were formerly declared here, but are now provided by
414  * the more general resource controls framework.)
415  */
416 
417 /*
418  * STREAMS tunables
419  */
420 int	nstrpush = 9;		/* maximum # of modules/drivers on a stream */
421 ssize_t	strctlsz = 1024;	/* maximum size of user-generated M_PROTO */
422 ssize_t	strmsgsz = 0x10000;	/* maximum size of user-generated M_DATA */
423 				/* for `strmsgsz', zero means unlimited */
424 /*
425  * Filesystem tunables
426  */
427 int	rstchown = 1;		/* POSIX_CHOWN_RESTRICTED is enabled */
428 int	ngroups_max = NGROUPS_MAX_DEFAULT;
429 
430 /*
431  * generic scheduling stuff
432  *
433  * Configurable parameters for RT and TS are in the respective
434  * scheduling class modules.
435  */
436 
437 pri_t maxclsyspri = MAXCLSYSPRI;
438 pri_t minclsyspri = MINCLSYSPRI;
439 char sys_name[] = "SYS";
440 
441 extern pri_t sys_init();
442 extern classfuncs_t sys_classfuncs;
443 
444 sclass_t sclass[] = {
445 	{ "SYS",	sys_init,	&sys_classfuncs, STATIC_SCHED, 0 },
446 	{ "",	NULL,	NULL,	NULL, 0 },
447 	{ "",	NULL,	NULL,	NULL, 0 },
448 	{ "",	NULL,	NULL,	NULL, 0 },
449 	{ "",	NULL,	NULL,	NULL, 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 };
456 
457 int loaded_classes = 1;		/* for loaded classes */
458 kmutex_t class_lock;		/* lock for class[] */
459 
460 int nclass = sizeof (sclass) / sizeof (sclass_t);
461 char initcls[] = "TS";
462 char *defaultclass = initcls;
463 
464 /*
465  * Tunable system parameters.
466  */
467 
468 /*
469  * The integers tune_* are done this way so that the tune
470  * data structure may be "tuned" if necessary from the /etc/system
471  * file. The tune data structure is initialized in param_init();
472  */
473 
474 tune_t tune;
475 
476 /*
477  * If freemem < t_getpgslow, then start to steal pages from processes.
478  */
479 int tune_t_gpgslo = 25;
480 
481 /*
482  * Rate at which fsflush is run, in seconds.
483  */
484 #define	DEFAULT_TUNE_T_FSFLUSHR	1
485 int tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
486 
487 /*
488  * The minimum available resident (not swappable) memory to maintain
489  * in order to avoid deadlock.  In pages.
490  */
491 int tune_t_minarmem = 25;
492 
493 /*
494  * The minimum available swappable memory to maintain in order to avoid
495  * deadlock.  In pages.
496  */
497 int tune_t_minasmem = 25;
498 
499 int tune_t_flckrec = 512;	/* max # of active frlocks */
500 
501 /*
502  * Number of currently available pages that cannot be 'locked'
503  * This is set in init_pages_pp_maximum, and must be initialized
504  * to zero here to detect an override in /etc/system
505  */
506 pgcnt_t pages_pp_maximum = 0;
507 
508 int boothowto;			/* boot flags passed to kernel */
509 struct var v;			/* System Configuration Information */
510 
511 /*
512  * System Configuration Information
513  */
514 
515 /*
516  * The physical system's host identifier, expressed as a decimal string.
517  * Code should only directly access this value when writing to it (setting the
518  * physical system's host identifier).  Code that reads the physical system's
519  * host identifier should use zone_get_hostid(NULL) instead.
520  */
521 char hw_serial[HW_HOSTID_LEN] = "0";
522 
523 #if defined(__sparc)
524 
525 /*
526  * On sparc machines, read hw_serial from the firmware at boot time
527  * and simply assert Sun is the hardware provider.  Hmm.
528  */
529 char architecture[] = "sparcv9";
530 char architecture_32[] = "sparc";
531 char hw_provider[] = "Sun_Microsystems";
532 
533 #elif defined(__i386)
534 
535 /*
536  * On x86 machines, read hw_serial, hw_provider and srpc_domain from
537  * /etc/bootrc at boot time.
538  */
539 char architecture[] = "i386";
540 char architecture_32[] = "i386";
541 char hw_provider[SYS_NMLN] = "";
542 
543 #elif defined(__amd64)
544 
545 /*
546  * On amd64 machines, read hw_serial, hw_provider and srpc_domain from
547  * /etc/bootrc at boot time.
548  */
549 char architecture[] = "amd64";
550 char architecture_32[] = "i386";
551 char hw_provider[SYS_NMLN] = "";
552 
553 #else
554 #error "unknown processor architecture"
555 #endif
556 
557 char srpc_domain[SYS_NMLN] = "";
558 char platform[SYS_NMLN] = "";	/* read from the devinfo root node */
559 
560 /* Initialize isa_list */
561 char *isa_list = architecture;
562 
563 static pgcnt_t original_physmem = 0;
564 
565 #define	MIN_DEFAULT_MAXUSERS	8u
566 #define	MAX_DEFAULT_MAXUSERS	2048u
567 #define	MAX_MAXUSERS		4096u
568 
569 void
570 param_preset(void)
571 {
572 	original_physmem = physmem;
573 }
574 
575 void
576 param_calc(int platform_max_nprocs)
577 {
578 	/*
579 	 * Default to about one "user" per megabyte, taking into
580 	 * account both physical and virtual constraints.
581 	 * Note: 2^20 is a meg; shifting right by (20 - PAGESHIFT)
582 	 * converts pages to megs without integer overflow.
583 	 */
584 #if defined(__sparc)
585 	if (physmem > original_physmem) {
586 		physmem = original_physmem;
587 		cmn_err(CE_NOTE, "physmem limited to %ld", physmem);
588 	}
589 #endif
590 	if (maxusers == 0) {
591 		pgcnt_t physmegs = physmem >> (20 - PAGESHIFT);
592 		pgcnt_t virtmegs = vmem_size(heap_arena, VMEM_FREE) >> 20;
593 		maxusers = MIN(MAX(MIN(physmegs, virtmegs),
594 		    MIN_DEFAULT_MAXUSERS), MAX_DEFAULT_MAXUSERS);
595 	}
596 	if (maxusers > MAX_MAXUSERS) {
597 		maxusers = MAX_MAXUSERS;
598 		cmn_err(CE_NOTE, "maxusers limited to %d", MAX_MAXUSERS);
599 	}
600 
601 	if (ngroups_max > NGROUPS_MAX_DEFAULT)
602 		cmn_err(CE_WARN, "ngroups_max of %d > %d, NFS AUTH_SYS will"
603 		    " not work properly", ngroups_max, NGROUPS_MAX_DEFAULT);
604 
605 #ifdef DEBUG
606 	/*
607 	 * The purpose of maxusers is to prevent memory overcommit.
608 	 * DEBUG kernels take more space, so reduce maxusers a bit.
609 	 */
610 	maxusers = (3 * maxusers) / 4;
611 #endif
612 
613 	/*
614 	 * We need to dynamically change any variables now so that
615 	 * the setting of maxusers and pidmax propagate to the other
616 	 * variables that are dependent on them.
617 	 */
618 	if (reserved_procs == 0)
619 		reserved_procs = 5;
620 	if (pidmax < reserved_procs || pidmax > MAX_MAXPID)
621 		maxpid = MAX_MAXPID;
622 	else
623 		maxpid = pidmax;
624 
625 	/*
626 	 * This allows platform-dependent code to constrain the maximum
627 	 * number of processes allowed in case there are e.g. VM limitations
628 	 * with how many contexts are available.
629 	 */
630 	if (max_nprocs == 0)
631 		max_nprocs = (10 + 16 * maxusers);
632 	if (platform_max_nprocs > 0 && max_nprocs > platform_max_nprocs)
633 		max_nprocs = platform_max_nprocs;
634 	if (max_nprocs > maxpid)
635 		max_nprocs = maxpid;
636 
637 	if (maxuprc == 0)
638 		maxuprc = (max_nprocs - reserved_procs);
639 }
640 
641 void
642 param_init(void)
643 {
644 	/*
645 	 * Set each individual element of struct var v to be the
646 	 * default value. This is done this way
647 	 * so that a user can set the assigned integer value in the
648 	 * /etc/system file *IF* tuning is needed.
649 	 */
650 	v.v_proc = max_nprocs;	/* v_proc - max # of processes system wide */
651 	v.v_maxupttl = max_nprocs - reserved_procs;
652 	v.v_maxsyspri = (int)maxclsyspri;  /* max global pri for sysclass */
653 	v.v_maxup = MIN(maxuprc, v.v_maxupttl); /* max procs per user */
654 	v.v_autoup = autoup;	/* v_autoup - delay for delayed writes */
655 
656 	/*
657 	 * Set each individual element of struct tune to be the
658 	 * default value. Each struct element This is done this way
659 	 *  so that a user can set the assigned integer value in the
660 	 * /etc/system file *IF* tuning is needed.
661 	 */
662 	tune.t_gpgslo = tune_t_gpgslo;
663 	tune.t_fsflushr = tune_t_fsflushr;
664 	tune.t_minarmem = tune_t_minarmem;
665 	tune.t_minasmem = tune_t_minasmem;
666 	tune.t_flckrec = tune_t_flckrec;
667 
668 	/*
669 	 * Initialization for file descriptors to correct mistaken settings in
670 	 * /etc/system.  Initialization of limits performed by resource control
671 	 * system.
672 	 */
673 	if (rlim_fd_cur > rlim_fd_max)
674 		rlim_fd_cur = rlim_fd_max;
675 
676 	/*
677 	 * calculations needed if hz was set in /etc/system
678 	 */
679 	if (hires_tick)
680 		hz = hires_hz;
681 
682 	tick_per_msec = hz / MILLISEC;
683 	msec_per_tick = MILLISEC / hz;
684 	usec_per_tick = MICROSEC / hz;
685 	nsec_per_tick = NANOSEC / hz;
686 	max_hres_adj = nsec_per_tick >> ADJ_SHIFT;
687 
688 	/*
689 	 * Consumers of relative timedwait functions must specify how accurately
690 	 * the given timeout must expire. This is currently TR_CLOCK_TICK for
691 	 * the vast majority of consumers, but nsec_per_tick becomes an
692 	 * artificial value in a tickless world. Each caller of such routines
693 	 * should re-evaluate their usage and specify the appropriate
694 	 * resolution.
695 	 */
696 	time_res[TR_NANOSEC] = SEC;
697 	time_res[TR_MICROSEC] = MILLISEC;
698 	time_res[TR_MILLISEC] = MICROSEC;
699 	time_res[TR_SEC] = NANOSEC;
700 	time_res[TR_CLOCK_TICK] = nsec_per_tick;
701 }
702 
703 /*
704  * Validate tuneable parameters following /etc/system processing,
705  * but prior to param_init().
706  */
707 void
708 param_check(void)
709 {
710 #if defined(__x86)
711 	if (physmem != original_physmem) {
712 		cmn_err(CE_NOTE, "physmem cannot be modified to 0x%lx"
713 		    " via /etc/system. Please use eeprom(1M) instead.",
714 		    physmem);
715 		physmem = original_physmem;
716 	}
717 #endif
718 	if (ngroups_max < NGROUPS_UMIN)
719 		ngroups_max = NGROUPS_UMIN;
720 	if (ngroups_max > NGROUPS_UMAX)
721 		ngroups_max = NGROUPS_UMAX;
722 
723 	/* If we have many groups then the ucred proto message also grows. */
724 	if (ngroups_max > NGROUPS_OLDMAX &&
725 	    strctlsz < (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) + 1024) {
726 		strctlsz = (ngroups_max - NGROUPS_OLDMAX) * sizeof (gid_t) +
727 		    1024;
728 	}
729 
730 	if (autoup <= 0) {
731 		autoup = DEFAULT_AUTOUP;
732 		cmn_err(CE_WARN, "autoup <= 0; defaulting to %d", autoup);
733 	}
734 
735 	if (tune_t_fsflushr <= 0) {
736 		tune_t_fsflushr = DEFAULT_TUNE_T_FSFLUSHR;
737 		cmn_err(CE_WARN, "tune_t_fsflushr <= 0; defaulting to %d",
738 		    tune_t_fsflushr);
739 	}
740 
741 	if (jump_pid < 0 || jump_pid >= pidmax) {
742 		jump_pid = 0;
743 		cmn_err(CE_WARN, "jump_pid < 0 or >= pidmax; ignored");
744 	}
745 
746 	if (snoop_interval < SNOOP_INTERVAL_MIN) {
747 		snoop_interval = SNOOP_INTERVAL_DEFAULT;
748 		cmn_err(CE_WARN, "snoop_interval < minimum (%d); defaulting"
749 		    " to %d", SNOOP_INTERVAL_MIN, SNOOP_INTERVAL_DEFAULT);
750 	}
751 }
752