1/*-
2 * Copyright (c) 1982, 1986, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94
| 1/*-
2 * Copyright (c) 1982, 1986, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 * may be used to endorse or promote products derived from this software
24 * without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94
|
40 */
41
42#include "opt_ntp.h"
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/dkstat.h>
47#include <sys/callout.h>
48#include <sys/kernel.h>
49#include <sys/lock.h>
50#include <sys/ktr.h>
51#include <sys/mutex.h>
52#include <sys/proc.h>
53#include <sys/resourcevar.h>
54#include <sys/signalvar.h>
55#include <sys/smp.h>
56#include <sys/timetc.h>
57#include <sys/timepps.h>
58#include <vm/vm.h>
59#include <vm/pmap.h>
60#include <vm/vm_map.h>
61#include <sys/sysctl.h>
62#include <sys/bus.h>
63#include <sys/interrupt.h>
64
65#include <machine/cpu.h>
66#include <machine/limits.h>
67
68#ifdef GPROF
69#include <sys/gmon.h>
70#endif
71
72#ifdef DEVICE_POLLING
73#include <net/netisr.h> /* for NETISR_POLL */
74
75extern void ether_poll1(void);
76extern void hardclock_device_poll(void);
77#endif /* DEVICE_POLLING */
78
79static void initclocks __P((void *dummy));
80SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
81
82/* Some of these don't belong here, but it's easiest to concentrate them. */
83long cp_time[CPUSTATES];
84
85SYSCTL_OPAQUE(_kern, OID_AUTO, cp_time, CTLFLAG_RD, &cp_time, sizeof(cp_time),
86 "LU", "CPU time statistics");
87
88long tk_cancc;
89long tk_nin;
90long tk_nout;
91long tk_rawcc;
92
93/*
94 * Clock handling routines.
95 *
96 * This code is written to operate with two timers that run independently of
97 * each other.
98 *
99 * The main timer, running hz times per second, is used to trigger interval
100 * timers, timeouts and rescheduling as needed.
101 *
102 * The second timer handles kernel and user profiling,
103 * and does resource use estimation. If the second timer is programmable,
104 * it is randomized to avoid aliasing between the two clocks. For example,
105 * the randomization prevents an adversary from always giving up the cpu
106 * just before its quantum expires. Otherwise, it would never accumulate
107 * cpu ticks. The mean frequency of the second timer is stathz.
108 *
109 * If no second timer exists, stathz will be zero; in this case we drive
110 * profiling and statistics off the main clock. This WILL NOT be accurate;
111 * do not do it unless absolutely necessary.
112 *
113 * The statistics clock may (or may not) be run at a higher rate while
114 * profiling. This profile clock runs at profhz. We require that profhz
115 * be an integral multiple of stathz.
116 *
117 * If the statistics clock is running fast, it must be divided by the ratio
118 * profhz/stathz for statistics. (For profiling, every tick counts.)
119 *
120 * Time-of-day is maintained using a "timecounter", which may or may
121 * not be related to the hardware generating the above mentioned
122 * interrupts.
123 */
124
125int stathz;
126int profhz;
127static int profprocs;
128int ticks;
129static int psdiv, pscnt; /* prof => stat divider */
130int psratio; /* ratio: prof / stat */
131
132/*
133 * Initialize clock frequencies and start both clocks running.
134 */
135/* ARGSUSED*/
136static void
137initclocks(dummy)
138 void *dummy;
139{
140 register int i;
141
142 /*
143 * Set divisors to 1 (normal case) and let the machine-specific
144 * code do its bit.
145 */
146 psdiv = pscnt = 1;
147 cpu_initclocks();
148
149#ifdef DEVICE_POLLING
150 register_netisr(NETISR_POLL, ether_poll1);
151#endif
152 /*
153 * Compute profhz/stathz, and fix profhz if needed.
154 */
155 i = stathz ? stathz : hz;
156 if (profhz == 0)
157 profhz = i;
158 psratio = profhz / i;
159}
160
161/*
162 * Each time the real-time timer fires, this function is called on all CPUs
163 * with each CPU passing in its curthread as the first argument. If possible
164 * a nice optimization in the future would be to allow the CPU receiving the
165 * actual real-time timer interrupt to call this function on behalf of the
166 * other CPUs rather than sending an IPI to all other CPUs so that they
167 * can call this function. Note that hardclock() calls hardclock_process()
168 * for the CPU receiving the timer interrupt, so only the other CPUs in the
169 * system need to call this function (or have it called on their behalf.
170 */
171void
172hardclock_process(td, user)
173 struct thread *td;
174 int user;
175{
176 struct pstats *pstats;
177 struct proc *p = td->td_proc;
178
179 /*
180 * Run current process's virtual and profile time, as needed.
181 */
182 mtx_assert(&sched_lock, MA_OWNED);
183 if (p->p_flag & P_KSES) {
184 /* XXXKSE What to do? */
185 } else {
186 pstats = p->p_stats;
187 if (user &&
188 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
189 itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) {
190 p->p_sflag |= PS_ALRMPEND;
191 td->td_kse->ke_flags |= KEF_ASTPENDING;
192 }
193 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
194 itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) {
195 p->p_sflag |= PS_PROFPEND;
196 td->td_kse->ke_flags |= KEF_ASTPENDING;
197 }
198 }
199}
200
201/*
202 * The real-time timer, interrupting hz times per second.
203 */
204void
205hardclock(frame)
206 register struct clockframe *frame;
207{
208 int need_softclock = 0;
209
210 CTR0(KTR_INTR, "hardclock fired");
211 mtx_lock_spin_flags(&sched_lock, MTX_QUIET);
212 hardclock_process(curthread, CLKF_USERMODE(frame));
213 mtx_unlock_spin_flags(&sched_lock, MTX_QUIET);
214
215 /*
216 * If no separate statistics clock is available, run it from here.
217 *
218 * XXX: this only works for UP
219 */
220 if (stathz == 0)
221 statclock(frame);
222
223 tc_windup();
224#ifdef DEVICE_POLLING
225 hardclock_device_poll();
226#endif /* DEVICE_POLLING */
227
228 /*
229 * Process callouts at a very low cpu priority, so we don't keep the
230 * relatively high clock interrupt priority any longer than necessary.
231 */
232 mtx_lock_spin_flags(&callout_lock, MTX_QUIET);
233 ticks++;
234 if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) {
235 need_softclock = 1;
236 } else if (softticks + 1 == ticks)
237 ++softticks;
238 mtx_unlock_spin_flags(&callout_lock, MTX_QUIET);
239
240 /*
241 * swi_sched acquires sched_lock, so we don't want to call it with
242 * callout_lock held; incorrect locking order.
243 */
244 if (need_softclock)
245 swi_sched(softclock_ih, SWI_NOSWITCH);
246}
247
248/*
249 * Compute number of ticks in the specified amount of time.
250 */
251int
252tvtohz(tv)
253 struct timeval *tv;
254{
255 register unsigned long ticks;
256 register long sec, usec;
257
258 /*
259 * If the number of usecs in the whole seconds part of the time
260 * difference fits in a long, then the total number of usecs will
261 * fit in an unsigned long. Compute the total and convert it to
262 * ticks, rounding up and adding 1 to allow for the current tick
263 * to expire. Rounding also depends on unsigned long arithmetic
264 * to avoid overflow.
265 *
266 * Otherwise, if the number of ticks in the whole seconds part of
267 * the time difference fits in a long, then convert the parts to
268 * ticks separately and add, using similar rounding methods and
269 * overflow avoidance. This method would work in the previous
270 * case but it is slightly slower and assumes that hz is integral.
271 *
272 * Otherwise, round the time difference down to the maximum
273 * representable value.
274 *
275 * If ints have 32 bits, then the maximum value for any timeout in
276 * 10ms ticks is 248 days.
277 */
278 sec = tv->tv_sec;
279 usec = tv->tv_usec;
280 if (usec < 0) {
281 sec--;
282 usec += 1000000;
283 }
284 if (sec < 0) {
285#ifdef DIAGNOSTIC
286 if (usec > 0) {
287 sec++;
288 usec -= 1000000;
289 }
290 printf("tvotohz: negative time difference %ld sec %ld usec\n",
291 sec, usec);
292#endif
293 ticks = 1;
294 } else if (sec <= LONG_MAX / 1000000)
295 ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1))
296 / tick + 1;
297 else if (sec <= LONG_MAX / hz)
298 ticks = sec * hz
299 + ((unsigned long)usec + (tick - 1)) / tick + 1;
300 else
301 ticks = LONG_MAX;
302 if (ticks > INT_MAX)
303 ticks = INT_MAX;
304 return ((int)ticks);
305}
306
307/*
308 * Start profiling on a process.
309 *
310 * Kernel profiling passes proc0 which never exits and hence
311 * keeps the profile clock running constantly.
312 */
313void
314startprofclock(p)
315 register struct proc *p;
316{
317 int s;
318
319 /*
320 * XXX; Right now sched_lock protects statclock(), but perhaps
321 * it should be protected later on by a time_lock, which would
322 * cover psdiv, etc. as well.
323 */
324 mtx_lock_spin(&sched_lock);
325 if ((p->p_sflag & PS_PROFIL) == 0) {
326 p->p_sflag |= PS_PROFIL;
327 if (++profprocs == 1 && stathz != 0) {
328 s = splstatclock();
329 psdiv = pscnt = psratio;
330 setstatclockrate(profhz);
331 splx(s);
332 }
333 }
334 mtx_unlock_spin(&sched_lock);
335}
336
337/*
338 * Stop profiling on a process.
339 */
340void
341stopprofclock(p)
342 register struct proc *p;
343{
344 int s;
345
346 mtx_lock_spin(&sched_lock);
347 if (p->p_sflag & PS_PROFIL) {
348 p->p_sflag &= ~PS_PROFIL;
349 if (--profprocs == 0 && stathz != 0) {
350 s = splstatclock();
351 psdiv = pscnt = 1;
352 setstatclockrate(stathz);
353 splx(s);
354 }
355 }
356 mtx_unlock_spin(&sched_lock);
357}
358
359/*
360 * Do process and kernel statistics. Most of the statistics are only
361 * used by user-level statistics programs. The main exceptions are
362 * ke->ke_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu. This function
363 * should be called by all CPUs in the system for each statistics clock
364 * interrupt. See the description of hardclock_process for more detail on
365 * this function's relationship to statclock.
366 */
367void
368statclock_process(ke, pc, user)
369 struct kse *ke;
370 register_t pc;
371 int user;
372{
373#ifdef GPROF
374 struct gmonparam *g;
375 int i;
376#endif
377 struct pstats *pstats;
378 long rss;
379 struct rusage *ru;
380 struct vmspace *vm;
381 struct proc *p = ke->ke_proc;
382 struct thread *td = ke->ke_thread; /* current thread */
383
384 KASSERT(ke == curthread->td_kse, ("statclock_process: td != curthread"));
385 mtx_assert(&sched_lock, MA_OWNED);
386 if (user) {
387 /*
388 * Came from user mode; CPU was in user state.
389 * If this process is being profiled, record the tick.
390 */
391 if (p->p_sflag & PS_PROFIL)
392 addupc_intr(ke, pc, 1);
393 if (pscnt < psdiv)
394 return;
395 /*
396 * Charge the time as appropriate.
397 */
398 ke->ke_uticks++;
399 if (ke->ke_ksegrp->kg_nice > NZERO)
400 cp_time[CP_NICE]++;
401 else
402 cp_time[CP_USER]++;
403 } else {
404#ifdef GPROF
405 /*
406 * Kernel statistics are just like addupc_intr, only easier.
407 */
408 g = &_gmonparam;
409 if (g->state == GMON_PROF_ON) {
410 i = pc - g->lowpc;
411 if (i < g->textsize) {
412 i /= HISTFRACTION * sizeof(*g->kcount);
413 g->kcount[i]++;
414 }
415 }
416#endif
417 if (pscnt < psdiv)
418 return;
419 /*
420 * Came from kernel mode, so we were:
421 * - handling an interrupt,
422 * - doing syscall or trap work on behalf of the current
423 * user process, or
424 * - spinning in the idle loop.
425 * Whichever it is, charge the time as appropriate.
426 * Note that we charge interrupts to the current process,
427 * regardless of whether they are ``for'' that process,
428 * so that we know how much of its real time was spent
429 * in ``non-process'' (i.e., interrupt) work.
430 */
431 if ((td->td_ithd != NULL) || td->td_intr_nesting_level >= 2) {
432 ke->ke_iticks++;
433 cp_time[CP_INTR]++;
434 } else {
435 ke->ke_sticks++;
436 if (p != PCPU_GET(idlethread)->td_proc)
437 cp_time[CP_SYS]++;
438 else
439 cp_time[CP_IDLE]++;
440 }
441 }
442
443 schedclock(ke->ke_thread);
444
445 /* Update resource usage integrals and maximums. */
446 if ((pstats = p->p_stats) != NULL &&
447 (ru = &pstats->p_ru) != NULL &&
448 (vm = p->p_vmspace) != NULL) {
449 ru->ru_ixrss += pgtok(vm->vm_tsize);
450 ru->ru_idrss += pgtok(vm->vm_dsize);
451 ru->ru_isrss += pgtok(vm->vm_ssize);
452 rss = pgtok(vmspace_resident_count(vm));
453 if (ru->ru_maxrss < rss)
454 ru->ru_maxrss = rss;
455 }
456}
457
458/*
459 * Statistics clock. Grab profile sample, and if divider reaches 0,
460 * do process and kernel statistics. Most of the statistics are only
461 * used by user-level statistics programs. The main exceptions are
462 * ke->ke_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu.
463 */
464void
465statclock(frame)
466 register struct clockframe *frame;
467{
468
469 CTR0(KTR_INTR, "statclock fired");
470 mtx_lock_spin_flags(&sched_lock, MTX_QUIET);
471 if (--pscnt == 0)
472 pscnt = psdiv;
473 statclock_process(curthread->td_kse, CLKF_PC(frame), CLKF_USERMODE(frame));
474 mtx_unlock_spin_flags(&sched_lock, MTX_QUIET);
475}
476
477/*
478 * Return information about system clocks.
479 */
480static int
481sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS)
482{
483 struct clockinfo clkinfo;
484 /*
485 * Construct clockinfo structure.
486 */
487 clkinfo.hz = hz;
488 clkinfo.tick = tick;
489 clkinfo.tickadj = tickadj;
490 clkinfo.profhz = profhz;
491 clkinfo.stathz = stathz ? stathz : hz;
492 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
493}
494
495SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
| 40 */
41
42#include "opt_ntp.h"
43
44#include <sys/param.h>
45#include <sys/systm.h>
46#include <sys/dkstat.h>
47#include <sys/callout.h>
48#include <sys/kernel.h>
49#include <sys/lock.h>
50#include <sys/ktr.h>
51#include <sys/mutex.h>
52#include <sys/proc.h>
53#include <sys/resourcevar.h>
54#include <sys/signalvar.h>
55#include <sys/smp.h>
56#include <sys/timetc.h>
57#include <sys/timepps.h>
58#include <vm/vm.h>
59#include <vm/pmap.h>
60#include <vm/vm_map.h>
61#include <sys/sysctl.h>
62#include <sys/bus.h>
63#include <sys/interrupt.h>
64
65#include <machine/cpu.h>
66#include <machine/limits.h>
67
68#ifdef GPROF
69#include <sys/gmon.h>
70#endif
71
72#ifdef DEVICE_POLLING
73#include <net/netisr.h> /* for NETISR_POLL */
74
75extern void ether_poll1(void);
76extern void hardclock_device_poll(void);
77#endif /* DEVICE_POLLING */
78
79static void initclocks __P((void *dummy));
80SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
81
82/* Some of these don't belong here, but it's easiest to concentrate them. */
83long cp_time[CPUSTATES];
84
85SYSCTL_OPAQUE(_kern, OID_AUTO, cp_time, CTLFLAG_RD, &cp_time, sizeof(cp_time),
86 "LU", "CPU time statistics");
87
88long tk_cancc;
89long tk_nin;
90long tk_nout;
91long tk_rawcc;
92
93/*
94 * Clock handling routines.
95 *
96 * This code is written to operate with two timers that run independently of
97 * each other.
98 *
99 * The main timer, running hz times per second, is used to trigger interval
100 * timers, timeouts and rescheduling as needed.
101 *
102 * The second timer handles kernel and user profiling,
103 * and does resource use estimation. If the second timer is programmable,
104 * it is randomized to avoid aliasing between the two clocks. For example,
105 * the randomization prevents an adversary from always giving up the cpu
106 * just before its quantum expires. Otherwise, it would never accumulate
107 * cpu ticks. The mean frequency of the second timer is stathz.
108 *
109 * If no second timer exists, stathz will be zero; in this case we drive
110 * profiling and statistics off the main clock. This WILL NOT be accurate;
111 * do not do it unless absolutely necessary.
112 *
113 * The statistics clock may (or may not) be run at a higher rate while
114 * profiling. This profile clock runs at profhz. We require that profhz
115 * be an integral multiple of stathz.
116 *
117 * If the statistics clock is running fast, it must be divided by the ratio
118 * profhz/stathz for statistics. (For profiling, every tick counts.)
119 *
120 * Time-of-day is maintained using a "timecounter", which may or may
121 * not be related to the hardware generating the above mentioned
122 * interrupts.
123 */
124
125int stathz;
126int profhz;
127static int profprocs;
128int ticks;
129static int psdiv, pscnt; /* prof => stat divider */
130int psratio; /* ratio: prof / stat */
131
132/*
133 * Initialize clock frequencies and start both clocks running.
134 */
135/* ARGSUSED*/
136static void
137initclocks(dummy)
138 void *dummy;
139{
140 register int i;
141
142 /*
143 * Set divisors to 1 (normal case) and let the machine-specific
144 * code do its bit.
145 */
146 psdiv = pscnt = 1;
147 cpu_initclocks();
148
149#ifdef DEVICE_POLLING
150 register_netisr(NETISR_POLL, ether_poll1);
151#endif
152 /*
153 * Compute profhz/stathz, and fix profhz if needed.
154 */
155 i = stathz ? stathz : hz;
156 if (profhz == 0)
157 profhz = i;
158 psratio = profhz / i;
159}
160
161/*
162 * Each time the real-time timer fires, this function is called on all CPUs
163 * with each CPU passing in its curthread as the first argument. If possible
164 * a nice optimization in the future would be to allow the CPU receiving the
165 * actual real-time timer interrupt to call this function on behalf of the
166 * other CPUs rather than sending an IPI to all other CPUs so that they
167 * can call this function. Note that hardclock() calls hardclock_process()
168 * for the CPU receiving the timer interrupt, so only the other CPUs in the
169 * system need to call this function (or have it called on their behalf.
170 */
171void
172hardclock_process(td, user)
173 struct thread *td;
174 int user;
175{
176 struct pstats *pstats;
177 struct proc *p = td->td_proc;
178
179 /*
180 * Run current process's virtual and profile time, as needed.
181 */
182 mtx_assert(&sched_lock, MA_OWNED);
183 if (p->p_flag & P_KSES) {
184 /* XXXKSE What to do? */
185 } else {
186 pstats = p->p_stats;
187 if (user &&
188 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
189 itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) {
190 p->p_sflag |= PS_ALRMPEND;
191 td->td_kse->ke_flags |= KEF_ASTPENDING;
192 }
193 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
194 itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) {
195 p->p_sflag |= PS_PROFPEND;
196 td->td_kse->ke_flags |= KEF_ASTPENDING;
197 }
198 }
199}
200
201/*
202 * The real-time timer, interrupting hz times per second.
203 */
204void
205hardclock(frame)
206 register struct clockframe *frame;
207{
208 int need_softclock = 0;
209
210 CTR0(KTR_INTR, "hardclock fired");
211 mtx_lock_spin_flags(&sched_lock, MTX_QUIET);
212 hardclock_process(curthread, CLKF_USERMODE(frame));
213 mtx_unlock_spin_flags(&sched_lock, MTX_QUIET);
214
215 /*
216 * If no separate statistics clock is available, run it from here.
217 *
218 * XXX: this only works for UP
219 */
220 if (stathz == 0)
221 statclock(frame);
222
223 tc_windup();
224#ifdef DEVICE_POLLING
225 hardclock_device_poll();
226#endif /* DEVICE_POLLING */
227
228 /*
229 * Process callouts at a very low cpu priority, so we don't keep the
230 * relatively high clock interrupt priority any longer than necessary.
231 */
232 mtx_lock_spin_flags(&callout_lock, MTX_QUIET);
233 ticks++;
234 if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) {
235 need_softclock = 1;
236 } else if (softticks + 1 == ticks)
237 ++softticks;
238 mtx_unlock_spin_flags(&callout_lock, MTX_QUIET);
239
240 /*
241 * swi_sched acquires sched_lock, so we don't want to call it with
242 * callout_lock held; incorrect locking order.
243 */
244 if (need_softclock)
245 swi_sched(softclock_ih, SWI_NOSWITCH);
246}
247
248/*
249 * Compute number of ticks in the specified amount of time.
250 */
251int
252tvtohz(tv)
253 struct timeval *tv;
254{
255 register unsigned long ticks;
256 register long sec, usec;
257
258 /*
259 * If the number of usecs in the whole seconds part of the time
260 * difference fits in a long, then the total number of usecs will
261 * fit in an unsigned long. Compute the total and convert it to
262 * ticks, rounding up and adding 1 to allow for the current tick
263 * to expire. Rounding also depends on unsigned long arithmetic
264 * to avoid overflow.
265 *
266 * Otherwise, if the number of ticks in the whole seconds part of
267 * the time difference fits in a long, then convert the parts to
268 * ticks separately and add, using similar rounding methods and
269 * overflow avoidance. This method would work in the previous
270 * case but it is slightly slower and assumes that hz is integral.
271 *
272 * Otherwise, round the time difference down to the maximum
273 * representable value.
274 *
275 * If ints have 32 bits, then the maximum value for any timeout in
276 * 10ms ticks is 248 days.
277 */
278 sec = tv->tv_sec;
279 usec = tv->tv_usec;
280 if (usec < 0) {
281 sec--;
282 usec += 1000000;
283 }
284 if (sec < 0) {
285#ifdef DIAGNOSTIC
286 if (usec > 0) {
287 sec++;
288 usec -= 1000000;
289 }
290 printf("tvotohz: negative time difference %ld sec %ld usec\n",
291 sec, usec);
292#endif
293 ticks = 1;
294 } else if (sec <= LONG_MAX / 1000000)
295 ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1))
296 / tick + 1;
297 else if (sec <= LONG_MAX / hz)
298 ticks = sec * hz
299 + ((unsigned long)usec + (tick - 1)) / tick + 1;
300 else
301 ticks = LONG_MAX;
302 if (ticks > INT_MAX)
303 ticks = INT_MAX;
304 return ((int)ticks);
305}
306
307/*
308 * Start profiling on a process.
309 *
310 * Kernel profiling passes proc0 which never exits and hence
311 * keeps the profile clock running constantly.
312 */
313void
314startprofclock(p)
315 register struct proc *p;
316{
317 int s;
318
319 /*
320 * XXX; Right now sched_lock protects statclock(), but perhaps
321 * it should be protected later on by a time_lock, which would
322 * cover psdiv, etc. as well.
323 */
324 mtx_lock_spin(&sched_lock);
325 if ((p->p_sflag & PS_PROFIL) == 0) {
326 p->p_sflag |= PS_PROFIL;
327 if (++profprocs == 1 && stathz != 0) {
328 s = splstatclock();
329 psdiv = pscnt = psratio;
330 setstatclockrate(profhz);
331 splx(s);
332 }
333 }
334 mtx_unlock_spin(&sched_lock);
335}
336
337/*
338 * Stop profiling on a process.
339 */
340void
341stopprofclock(p)
342 register struct proc *p;
343{
344 int s;
345
346 mtx_lock_spin(&sched_lock);
347 if (p->p_sflag & PS_PROFIL) {
348 p->p_sflag &= ~PS_PROFIL;
349 if (--profprocs == 0 && stathz != 0) {
350 s = splstatclock();
351 psdiv = pscnt = 1;
352 setstatclockrate(stathz);
353 splx(s);
354 }
355 }
356 mtx_unlock_spin(&sched_lock);
357}
358
359/*
360 * Do process and kernel statistics. Most of the statistics are only
361 * used by user-level statistics programs. The main exceptions are
362 * ke->ke_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu. This function
363 * should be called by all CPUs in the system for each statistics clock
364 * interrupt. See the description of hardclock_process for more detail on
365 * this function's relationship to statclock.
366 */
367void
368statclock_process(ke, pc, user)
369 struct kse *ke;
370 register_t pc;
371 int user;
372{
373#ifdef GPROF
374 struct gmonparam *g;
375 int i;
376#endif
377 struct pstats *pstats;
378 long rss;
379 struct rusage *ru;
380 struct vmspace *vm;
381 struct proc *p = ke->ke_proc;
382 struct thread *td = ke->ke_thread; /* current thread */
383
384 KASSERT(ke == curthread->td_kse, ("statclock_process: td != curthread"));
385 mtx_assert(&sched_lock, MA_OWNED);
386 if (user) {
387 /*
388 * Came from user mode; CPU was in user state.
389 * If this process is being profiled, record the tick.
390 */
391 if (p->p_sflag & PS_PROFIL)
392 addupc_intr(ke, pc, 1);
393 if (pscnt < psdiv)
394 return;
395 /*
396 * Charge the time as appropriate.
397 */
398 ke->ke_uticks++;
399 if (ke->ke_ksegrp->kg_nice > NZERO)
400 cp_time[CP_NICE]++;
401 else
402 cp_time[CP_USER]++;
403 } else {
404#ifdef GPROF
405 /*
406 * Kernel statistics are just like addupc_intr, only easier.
407 */
408 g = &_gmonparam;
409 if (g->state == GMON_PROF_ON) {
410 i = pc - g->lowpc;
411 if (i < g->textsize) {
412 i /= HISTFRACTION * sizeof(*g->kcount);
413 g->kcount[i]++;
414 }
415 }
416#endif
417 if (pscnt < psdiv)
418 return;
419 /*
420 * Came from kernel mode, so we were:
421 * - handling an interrupt,
422 * - doing syscall or trap work on behalf of the current
423 * user process, or
424 * - spinning in the idle loop.
425 * Whichever it is, charge the time as appropriate.
426 * Note that we charge interrupts to the current process,
427 * regardless of whether they are ``for'' that process,
428 * so that we know how much of its real time was spent
429 * in ``non-process'' (i.e., interrupt) work.
430 */
431 if ((td->td_ithd != NULL) || td->td_intr_nesting_level >= 2) {
432 ke->ke_iticks++;
433 cp_time[CP_INTR]++;
434 } else {
435 ke->ke_sticks++;
436 if (p != PCPU_GET(idlethread)->td_proc)
437 cp_time[CP_SYS]++;
438 else
439 cp_time[CP_IDLE]++;
440 }
441 }
442
443 schedclock(ke->ke_thread);
444
445 /* Update resource usage integrals and maximums. */
446 if ((pstats = p->p_stats) != NULL &&
447 (ru = &pstats->p_ru) != NULL &&
448 (vm = p->p_vmspace) != NULL) {
449 ru->ru_ixrss += pgtok(vm->vm_tsize);
450 ru->ru_idrss += pgtok(vm->vm_dsize);
451 ru->ru_isrss += pgtok(vm->vm_ssize);
452 rss = pgtok(vmspace_resident_count(vm));
453 if (ru->ru_maxrss < rss)
454 ru->ru_maxrss = rss;
455 }
456}
457
458/*
459 * Statistics clock. Grab profile sample, and if divider reaches 0,
460 * do process and kernel statistics. Most of the statistics are only
461 * used by user-level statistics programs. The main exceptions are
462 * ke->ke_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu.
463 */
464void
465statclock(frame)
466 register struct clockframe *frame;
467{
468
469 CTR0(KTR_INTR, "statclock fired");
470 mtx_lock_spin_flags(&sched_lock, MTX_QUIET);
471 if (--pscnt == 0)
472 pscnt = psdiv;
473 statclock_process(curthread->td_kse, CLKF_PC(frame), CLKF_USERMODE(frame));
474 mtx_unlock_spin_flags(&sched_lock, MTX_QUIET);
475}
476
477/*
478 * Return information about system clocks.
479 */
480static int
481sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS)
482{
483 struct clockinfo clkinfo;
484 /*
485 * Construct clockinfo structure.
486 */
487 clkinfo.hz = hz;
488 clkinfo.tick = tick;
489 clkinfo.tickadj = tickadj;
490 clkinfo.profhz = profhz;
491 clkinfo.stathz = stathz ? stathz : hz;
492 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
493}
494
495SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
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