Commit | Line | Data |
---|---|---|
da7c5cc6 | 1 | /* |
0880b18e | 2 | * Copyright (c) 1982, 1986 Regents of the University of California. |
da7c5cc6 KM |
3 | * All rights reserved. The Berkeley software License Agreement |
4 | * specifies the terms and conditions for redistribution. | |
5 | * | |
0880b18e | 6 | * @(#)kern_clock.c 7.1 (Berkeley) %G% |
da7c5cc6 | 7 | */ |
961945a8 SL |
8 | |
9 | #include "../machine/reg.h" | |
10 | #include "../machine/psl.h" | |
83be5fac | 11 | |
94368568 JB |
12 | #include "param.h" |
13 | #include "systm.h" | |
14 | #include "dk.h" | |
15 | #include "callout.h" | |
16 | #include "dir.h" | |
17 | #include "user.h" | |
18 | #include "kernel.h" | |
19 | #include "proc.h" | |
20 | #include "vm.h" | |
21 | #include "text.h" | |
83be5fac | 22 | |
9c5cfb8b | 23 | #if defined(vax) |
961945a8 | 24 | #include "../vax/mtpr.h" |
9c5cfb8b | 25 | #include "../vax/clock.h" |
961945a8 SL |
26 | #endif |
27 | ||
8487304f | 28 | #ifdef GPROF |
94368568 | 29 | #include "gprof.h" |
8487304f KM |
30 | #endif |
31 | ||
45e9acec MK |
32 | #define ADJTIME /* For now... */ |
33 | #define ADJ_TICK 1000 | |
34 | int adjtimedelta; | |
35 | ||
76b2a182 BJ |
36 | /* |
37 | * Clock handling routines. | |
38 | * | |
53a32545 SL |
39 | * This code is written to operate with two timers which run |
40 | * independently of each other. The main clock, running at hz | |
41 | * times per second, is used to do scheduling and timeout calculations. | |
42 | * The second timer does resource utilization estimation statistically | |
43 | * based on the state of the machine phz times a second. Both functions | |
44 | * can be performed by a single clock (ie hz == phz), however the | |
45 | * statistics will be much more prone to errors. Ideally a machine | |
46 | * would have separate clocks measuring time spent in user state, system | |
47 | * state, interrupt state, and idle state. These clocks would allow a non- | |
48 | * approximate measure of resource utilization. | |
76b2a182 | 49 | */ |
6602c75b | 50 | |
76b2a182 BJ |
51 | /* |
52 | * TODO: | |
88a7a62a SL |
53 | * time of day, system/user timing, timeouts, profiling on separate timers |
54 | * allocate more timeout table slots when table overflows. | |
76b2a182 | 55 | */ |
9c5cfb8b | 56 | |
ad8023d1 KM |
57 | /* |
58 | * Bump a timeval by a small number of usec's. | |
59 | */ | |
ad8023d1 KM |
60 | #define BUMPTIME(t, usec) { \ |
61 | register struct timeval *tp = (t); \ | |
62 | \ | |
63 | tp->tv_usec += (usec); \ | |
64 | if (tp->tv_usec >= 1000000) { \ | |
65 | tp->tv_usec -= 1000000; \ | |
66 | tp->tv_sec++; \ | |
67 | } \ | |
68 | } | |
83be5fac | 69 | |
76b2a182 | 70 | /* |
53a32545 SL |
71 | * The hz hardware interval timer. |
72 | * We update the events relating to real time. | |
73 | * If this timer is also being used to gather statistics, | |
74 | * we run through the statistics gathering routine as well. | |
76b2a182 | 75 | */ |
260ea681 | 76 | /*ARGSUSED*/ |
f403d99f | 77 | hardclock(pc, ps) |
4512b9a4 | 78 | caddr_t pc; |
460ab27f | 79 | int ps; |
83be5fac | 80 | { |
0a34b6fd | 81 | register struct callout *p1; |
27b91f59 | 82 | register struct proc *p; |
0b355a6e | 83 | register int s; |
83be5fac | 84 | |
76b2a182 BJ |
85 | /* |
86 | * Update real-time timeout queue. | |
87 | * At front of queue are some number of events which are ``due''. | |
88 | * The time to these is <= 0 and if negative represents the | |
89 | * number of ticks which have passed since it was supposed to happen. | |
90 | * The rest of the q elements (times > 0) are events yet to happen, | |
91 | * where the time for each is given as a delta from the previous. | |
92 | * Decrementing just the first of these serves to decrement the time | |
93 | * to all events. | |
94 | */ | |
88a7a62a SL |
95 | p1 = calltodo.c_next; |
96 | while (p1) { | |
97 | if (--p1->c_time > 0) | |
98 | break; | |
88a7a62a SL |
99 | if (p1->c_time == 0) |
100 | break; | |
101 | p1 = p1->c_next; | |
102 | } | |
5da67d35 | 103 | |
76b2a182 BJ |
104 | /* |
105 | * Charge the time out based on the mode the cpu is in. | |
106 | * Here again we fudge for the lack of proper interval timers | |
107 | * assuming that the current state has been around at least | |
108 | * one tick. | |
109 | */ | |
83be5fac | 110 | if (USERMODE(ps)) { |
76b2a182 BJ |
111 | /* |
112 | * CPU was in user state. Increment | |
113 | * user time counter, and process process-virtual time | |
877ef342 | 114 | * interval timer. |
76b2a182 | 115 | */ |
ad8023d1 | 116 | BUMPTIME(&u.u_ru.ru_utime, tick); |
27b91f59 BJ |
117 | if (timerisset(&u.u_timer[ITIMER_VIRTUAL].it_value) && |
118 | itimerdecr(&u.u_timer[ITIMER_VIRTUAL], tick) == 0) | |
119 | psignal(u.u_procp, SIGVTALRM); | |
83be5fac | 120 | } else { |
76b2a182 | 121 | /* |
0b355a6e | 122 | * CPU was in system state. |
76b2a182 | 123 | */ |
9c5cfb8b | 124 | if (!noproc) |
ad8023d1 | 125 | BUMPTIME(&u.u_ru.ru_stime, tick); |
83be5fac | 126 | } |
27b91f59 | 127 | |
9fb1a8d0 SL |
128 | /* |
129 | * If the cpu is currently scheduled to a process, then | |
130 | * charge it with resource utilization for a tick, updating | |
131 | * statistics which run in (user+system) virtual time, | |
132 | * such as the cpu time limit and profiling timers. | |
133 | * This assumes that the current process has been running | |
134 | * the entire last tick. | |
135 | */ | |
405de916 | 136 | if (noproc == 0) { |
9fb1a8d0 SL |
137 | if ((u.u_ru.ru_utime.tv_sec+u.u_ru.ru_stime.tv_sec+1) > |
138 | u.u_rlimit[RLIMIT_CPU].rlim_cur) { | |
139 | psignal(u.u_procp, SIGXCPU); | |
140 | if (u.u_rlimit[RLIMIT_CPU].rlim_cur < | |
141 | u.u_rlimit[RLIMIT_CPU].rlim_max) | |
142 | u.u_rlimit[RLIMIT_CPU].rlim_cur += 5; | |
143 | } | |
144 | if (timerisset(&u.u_timer[ITIMER_PROF].it_value) && | |
145 | itimerdecr(&u.u_timer[ITIMER_PROF], tick) == 0) | |
146 | psignal(u.u_procp, SIGPROF); | |
147 | s = u.u_procp->p_rssize; | |
9c5cfb8b MK |
148 | u.u_ru.ru_idrss += s; |
149 | #ifdef notdef | |
150 | u.u_ru.ru_isrss += 0; /* XXX (haven't got this) */ | |
151 | #endif | |
9fb1a8d0 SL |
152 | if (u.u_procp->p_textp) { |
153 | register int xrss = u.u_procp->p_textp->x_rssize; | |
154 | ||
155 | s += xrss; | |
156 | u.u_ru.ru_ixrss += xrss; | |
157 | } | |
158 | if (s > u.u_ru.ru_maxrss) | |
159 | u.u_ru.ru_maxrss = s; | |
160 | } | |
161 | ||
76b2a182 BJ |
162 | /* |
163 | * We adjust the priority of the current process. | |
164 | * The priority of a process gets worse as it accumulates | |
165 | * CPU time. The cpu usage estimator (p_cpu) is increased here | |
166 | * and the formula for computing priorities (in kern_synch.c) | |
167 | * will compute a different value each time the p_cpu increases | |
168 | * by 4. The cpu usage estimator ramps up quite quickly when | |
169 | * the process is running (linearly), and decays away exponentially, | |
170 | * at a rate which is proportionally slower when the system is | |
171 | * busy. The basic principal is that the system will 90% forget | |
172 | * that a process used a lot of CPU time in 5*loadav seconds. | |
173 | * This causes the system to favor processes which haven't run | |
174 | * much recently, and to round-robin among other processes. | |
175 | */ | |
83be5fac | 176 | if (!noproc) { |
27b91f59 BJ |
177 | p = u.u_procp; |
178 | p->p_cpticks++; | |
179 | if (++p->p_cpu == 0) | |
180 | p->p_cpu--; | |
76b2a182 | 181 | if ((p->p_cpu&3) == 0) { |
27b91f59 BJ |
182 | (void) setpri(p); |
183 | if (p->p_pri >= PUSER) | |
184 | p->p_pri = p->p_usrpri; | |
83be5fac BJ |
185 | } |
186 | } | |
76b2a182 | 187 | |
53a32545 SL |
188 | /* |
189 | * If the alternate clock has not made itself known then | |
190 | * we must gather the statistics. | |
191 | */ | |
192 | if (phz == 0) | |
193 | gatherstats(pc, ps); | |
53a32545 | 194 | |
76b2a182 BJ |
195 | /* |
196 | * Increment the time-of-day, and schedule | |
197 | * processing of the callouts at a very low cpu priority, | |
198 | * so we don't keep the relatively high clock interrupt | |
199 | * priority any longer than necessary. | |
200 | */ | |
45e9acec MK |
201 | #ifdef ADJTIME |
202 | if (adjtimedelta == 0) | |
203 | bumptime(&time, tick); | |
204 | else { | |
205 | if (adjtimedelta < 0) { | |
206 | bumptime(&time, tick-ADJ_TICK); | |
207 | adjtimedelta++; | |
208 | } else { | |
209 | bumptime(&time, tick+ADJ_TICK); | |
210 | adjtimedelta--; | |
211 | } | |
212 | } | |
213 | #else | |
4ca0d0d6 | 214 | if (timedelta == 0) |
99e47f6b MK |
215 | BUMPTIME(&time, tick) |
216 | else { | |
217 | register delta; | |
218 | ||
4ca0d0d6 MK |
219 | if (timedelta < 0) { |
220 | delta = tick - tickdelta; | |
221 | timedelta += tickdelta; | |
99e47f6b | 222 | } else { |
4ca0d0d6 MK |
223 | delta = tick + tickdelta; |
224 | timedelta -= tickdelta; | |
99e47f6b MK |
225 | } |
226 | BUMPTIME(&time, delta); | |
227 | } | |
45e9acec | 228 | #endif |
ca6b57a4 | 229 | setsoftclock(); |
f403d99f BJ |
230 | } |
231 | ||
d976d466 | 232 | int dk_ndrive = DK_NDRIVE; |
53a32545 SL |
233 | /* |
234 | * Gather statistics on resource utilization. | |
235 | * | |
236 | * We make a gross assumption: that the system has been in the | |
237 | * state it is in (user state, kernel state, interrupt state, | |
238 | * or idle state) for the entire last time interval, and | |
239 | * update statistics accordingly. | |
240 | */ | |
88a7a62a | 241 | /*ARGSUSED*/ |
53a32545 SL |
242 | gatherstats(pc, ps) |
243 | caddr_t pc; | |
244 | int ps; | |
245 | { | |
9c5cfb8b | 246 | register int cpstate, s; |
53a32545 SL |
247 | |
248 | /* | |
249 | * Determine what state the cpu is in. | |
250 | */ | |
251 | if (USERMODE(ps)) { | |
252 | /* | |
253 | * CPU was in user state. | |
254 | */ | |
255 | if (u.u_procp->p_nice > NZERO) | |
256 | cpstate = CP_NICE; | |
257 | else | |
258 | cpstate = CP_USER; | |
259 | } else { | |
260 | /* | |
261 | * CPU was in system state. If profiling kernel | |
0b355a6e JB |
262 | * increment a counter. If no process is running |
263 | * then this is a system tick if we were running | |
264 | * at a non-zero IPL (in a driver). If a process is running, | |
265 | * then we charge it with system time even if we were | |
266 | * at a non-zero IPL, since the system often runs | |
267 | * this way during processing of system calls. | |
268 | * This is approximate, but the lack of true interval | |
269 | * timers makes doing anything else difficult. | |
53a32545 SL |
270 | */ |
271 | cpstate = CP_SYS; | |
272 | if (noproc && BASEPRI(ps)) | |
273 | cpstate = CP_IDLE; | |
274 | #ifdef GPROF | |
275 | s = pc - s_lowpc; | |
276 | if (profiling < 2 && s < s_textsize) | |
277 | kcount[s / (HISTFRACTION * sizeof (*kcount))]++; | |
278 | #endif | |
279 | } | |
280 | /* | |
281 | * We maintain statistics shown by user-level statistics | |
282 | * programs: the amount of time in each cpu state, and | |
283 | * the amount of time each of DK_NDRIVE ``drives'' is busy. | |
284 | */ | |
285 | cp_time[cpstate]++; | |
286 | for (s = 0; s < DK_NDRIVE; s++) | |
9c5cfb8b | 287 | if (dk_busy & (1 << s)) |
53a32545 SL |
288 | dk_time[s]++; |
289 | } | |
290 | ||
76b2a182 BJ |
291 | /* |
292 | * Software priority level clock interrupt. | |
293 | * Run periodic events from timeout queue. | |
294 | */ | |
260ea681 | 295 | /*ARGSUSED*/ |
f403d99f | 296 | softclock(pc, ps) |
4512b9a4 | 297 | caddr_t pc; |
460ab27f | 298 | int ps; |
f403d99f | 299 | { |
f403d99f | 300 | |
27b91f59 | 301 | for (;;) { |
76b2a182 BJ |
302 | register struct callout *p1; |
303 | register caddr_t arg; | |
304 | register int (*func)(); | |
305 | register int a, s; | |
306 | ||
9c5cfb8b | 307 | s = splhigh(); |
27b91f59 BJ |
308 | if ((p1 = calltodo.c_next) == 0 || p1->c_time > 0) { |
309 | splx(s); | |
310 | break; | |
f403d99f | 311 | } |
76b2a182 | 312 | arg = p1->c_arg; func = p1->c_func; a = p1->c_time; |
27b91f59 | 313 | calltodo.c_next = p1->c_next; |
27b91f59 BJ |
314 | p1->c_next = callfree; |
315 | callfree = p1; | |
4f083fd7 | 316 | splx(s); |
d01b68d6 | 317 | (*func)(arg, a); |
f403d99f | 318 | } |
877ef342 | 319 | /* |
db1f1262 SL |
320 | * If trapped user-mode and profiling, give it |
321 | * a profiling tick. | |
877ef342 | 322 | */ |
db1f1262 SL |
323 | if (USERMODE(ps)) { |
324 | register struct proc *p = u.u_procp; | |
325 | ||
326 | if (u.u_prof.pr_scale) { | |
327 | p->p_flag |= SOWEUPC; | |
328 | aston(); | |
329 | } | |
db1f1262 SL |
330 | /* |
331 | * Check to see if process has accumulated | |
332 | * more than 10 minutes of user time. If so | |
333 | * reduce priority to give others a chance. | |
334 | */ | |
335 | if (p->p_uid && p->p_nice == NZERO && | |
336 | u.u_ru.ru_utime.tv_sec > 10 * 60) { | |
337 | p->p_nice = NZERO+4; | |
338 | (void) setpri(p); | |
339 | p->p_pri = p->p_usrpri; | |
340 | } | |
877ef342 | 341 | } |
83be5fac BJ |
342 | } |
343 | ||
88a7a62a SL |
344 | /* |
345 | * Arrange that (*fun)(arg) is called in t/hz seconds. | |
83be5fac | 346 | */ |
88a7a62a | 347 | timeout(fun, arg, t) |
4512b9a4 BJ |
348 | int (*fun)(); |
349 | caddr_t arg; | |
88a7a62a | 350 | register int t; |
83be5fac | 351 | { |
c4710996 | 352 | register struct callout *p1, *p2, *pnew; |
9c5cfb8b | 353 | register int s = splhigh(); |
83be5fac | 354 | |
ba96129b | 355 | if (t <= 0) |
88a7a62a | 356 | t = 1; |
c4710996 BJ |
357 | pnew = callfree; |
358 | if (pnew == NULL) | |
359 | panic("timeout table overflow"); | |
360 | callfree = pnew->c_next; | |
361 | pnew->c_arg = arg; | |
362 | pnew->c_func = fun; | |
363 | for (p1 = &calltodo; (p2 = p1->c_next) && p2->c_time < t; p1 = p2) | |
d45b61eb SL |
364 | if (p2->c_time > 0) |
365 | t -= p2->c_time; | |
c4710996 BJ |
366 | p1->c_next = pnew; |
367 | pnew->c_next = p2; | |
368 | pnew->c_time = t; | |
369 | if (p2) | |
370 | p2->c_time -= t; | |
83be5fac BJ |
371 | splx(s); |
372 | } | |
1fa9ff62 SL |
373 | |
374 | /* | |
375 | * untimeout is called to remove a function timeout call | |
376 | * from the callout structure. | |
377 | */ | |
27b91f59 | 378 | untimeout(fun, arg) |
1fa9ff62 SL |
379 | int (*fun)(); |
380 | caddr_t arg; | |
381 | { | |
1fa9ff62 SL |
382 | register struct callout *p1, *p2; |
383 | register int s; | |
384 | ||
9c5cfb8b | 385 | s = splhigh(); |
1fa9ff62 SL |
386 | for (p1 = &calltodo; (p2 = p1->c_next) != 0; p1 = p2) { |
387 | if (p2->c_func == fun && p2->c_arg == arg) { | |
d01b68d6 | 388 | if (p2->c_next && p2->c_time > 0) |
1fa9ff62 SL |
389 | p2->c_next->c_time += p2->c_time; |
390 | p1->c_next = p2->c_next; | |
391 | p2->c_next = callfree; | |
392 | callfree = p2; | |
393 | break; | |
394 | } | |
395 | } | |
396 | splx(s); | |
397 | } | |
d01b68d6 | 398 | |
76b2a182 BJ |
399 | /* |
400 | * Compute number of hz until specified time. | |
401 | * Used to compute third argument to timeout() from an | |
402 | * absolute time. | |
403 | */ | |
d01b68d6 BJ |
404 | hzto(tv) |
405 | struct timeval *tv; | |
406 | { | |
76b2a182 BJ |
407 | register long ticks; |
408 | register long sec; | |
9c5cfb8b | 409 | int s = splhigh(); |
d01b68d6 | 410 | |
76b2a182 BJ |
411 | /* |
412 | * If number of milliseconds will fit in 32 bit arithmetic, | |
413 | * then compute number of milliseconds to time and scale to | |
414 | * ticks. Otherwise just compute number of hz in time, rounding | |
415 | * times greater than representible to maximum value. | |
416 | * | |
417 | * Delta times less than 25 days can be computed ``exactly''. | |
418 | * Maximum value for any timeout in 10ms ticks is 250 days. | |
419 | */ | |
420 | sec = tv->tv_sec - time.tv_sec; | |
421 | if (sec <= 0x7fffffff / 1000 - 1000) | |
422 | ticks = ((tv->tv_sec - time.tv_sec) * 1000 + | |
423 | (tv->tv_usec - time.tv_usec) / 1000) / (tick / 1000); | |
424 | else if (sec <= 0x7fffffff / hz) | |
425 | ticks = sec * hz; | |
426 | else | |
427 | ticks = 0x7fffffff; | |
d01b68d6 BJ |
428 | splx(s); |
429 | return (ticks); | |
430 | } | |
88a7a62a SL |
431 | |
432 | profil() | |
433 | { | |
434 | register struct a { | |
435 | short *bufbase; | |
436 | unsigned bufsize; | |
437 | unsigned pcoffset; | |
438 | unsigned pcscale; | |
439 | } *uap = (struct a *)u.u_ap; | |
440 | register struct uprof *upp = &u.u_prof; | |
441 | ||
442 | upp->pr_base = uap->bufbase; | |
443 | upp->pr_size = uap->bufsize; | |
444 | upp->pr_off = uap->pcoffset; | |
445 | upp->pr_scale = uap->pcscale; | |
446 | } | |
447 | ||
9c5cfb8b | 448 | #ifdef COMPAT |
88a7a62a SL |
449 | opause() |
450 | { | |
451 | ||
452 | for (;;) | |
453 | sleep((caddr_t)&u, PSLEP); | |
454 | } | |
9c5cfb8b | 455 | #endif |