subr_prof.c revision 35596
11541Srgrimes/*- 21541Srgrimes * Copyright (c) 1982, 1986, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * Redistribution and use in source and binary forms, with or without 61541Srgrimes * modification, are permitted provided that the following conditions 71541Srgrimes * are met: 81541Srgrimes * 1. Redistributions of source code must retain the above copyright 91541Srgrimes * notice, this list of conditions and the following disclaimer. 101541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111541Srgrimes * notice, this list of conditions and the following disclaimer in the 121541Srgrimes * documentation and/or other materials provided with the distribution. 131541Srgrimes * 3. All advertising materials mentioning features or use of this software 141541Srgrimes * must display the following acknowledgement: 151541Srgrimes * This product includes software developed by the University of 161541Srgrimes * California, Berkeley and its contributors. 171541Srgrimes * 4. Neither the name of the University nor the names of its contributors 181541Srgrimes * may be used to endorse or promote products derived from this software 191541Srgrimes * without specific prior written permission. 201541Srgrimes * 211541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311541Srgrimes * SUCH DAMAGE. 321541Srgrimes * 331541Srgrimes * @(#)subr_prof.c 8.3 (Berkeley) 9/23/93 3435596Sbde * $Id: subr_prof.c,v 1.25 1998/04/15 17:46:23 bde Exp $ 351541Srgrimes */ 361541Srgrimes 371541Srgrimes#include <sys/param.h> 381541Srgrimes#include <sys/systm.h> 3912221Sbde#include <sys/sysproto.h> 401541Srgrimes#include <sys/kernel.h> 411541Srgrimes#include <sys/proc.h> 4212657Sbde#include <sys/resourcevar.h> 437090Sbde#include <sys/sysctl.h> 447090Sbde 451541Srgrimes#include <machine/cpu.h> 461541Srgrimes 471541Srgrimes#ifdef GPROF 481541Srgrimes#include <sys/malloc.h> 491541Srgrimes#include <sys/gmon.h> 501541Srgrimes 5130354Sphkstatic MALLOC_DEFINE(M_GPROF, "gprof", "kernel profiling buffer"); 5230309Sphk 5310653Sdgstatic void kmstartup __P((void *)); 5410358SjulianSYSINIT(kmem, SI_SUB_KPROF, SI_ORDER_FIRST, kmstartup, NULL) 5510358Sjulian 561541Srgrimesstruct gmonparam _gmonparam = { GMON_PROF_OFF }; 571541Srgrimes 5819000Sbde#ifdef GUPROF 5919000Sbdevoid 6019000Sbdenullfunc_loop_profiled() 6119000Sbde{ 6219000Sbde int i; 6319000Sbde 6419000Sbde for (i = 0; i < CALIB_SCALE; i++) 6519000Sbde nullfunc_profiled(); 6619000Sbde} 6719000Sbde 6820396Sbde#define nullfunc_loop_profiled_end nullfunc_profiled /* XXX */ 6920396Sbde 7019000Sbdevoid 7119000Sbdenullfunc_profiled() 7219000Sbde{ 7319000Sbde} 7419000Sbde#endif /* GUPROF */ 7519000Sbde 7610407Sbdestatic void 7712569Sbdekmstartup(dummy) 7812569Sbde void *dummy; 791541Srgrimes{ 801541Srgrimes char *cp; 811541Srgrimes struct gmonparam *p = &_gmonparam; 8213107Sbde#ifdef GUPROF 8319000Sbde int cputime_overhead; 8419000Sbde int empty_loop_time; 8519000Sbde int i; 8619000Sbde int mcount_overhead; 8719000Sbde int mexitcount_overhead; 8819000Sbde int nullfunc_loop_overhead; 8919000Sbde int nullfunc_loop_profiled_time; 9020396Sbde fptrint_t tmp_addr; 9113107Sbde#endif 9213107Sbde 931541Srgrimes /* 941541Srgrimes * Round lowpc and highpc to multiples of the density we're using 951541Srgrimes * so the rest of the scaling (here and in gprof) stays in ints. 961541Srgrimes */ 976009Sbde p->lowpc = ROUNDDOWN((u_long)btext, HISTFRACTION * sizeof(HISTCOUNTER)); 981541Srgrimes p->highpc = ROUNDUP((u_long)etext, HISTFRACTION * sizeof(HISTCOUNTER)); 991541Srgrimes p->textsize = p->highpc - p->lowpc; 10019000Sbde printf("Profiling kernel, textsize=%lu [%x..%x]\n", 1011541Srgrimes p->textsize, p->lowpc, p->highpc); 1021541Srgrimes p->kcountsize = p->textsize / HISTFRACTION; 1031541Srgrimes p->hashfraction = HASHFRACTION; 1041541Srgrimes p->fromssize = p->textsize / HASHFRACTION; 1051541Srgrimes p->tolimit = p->textsize * ARCDENSITY / 100; 1061541Srgrimes if (p->tolimit < MINARCS) 1071541Srgrimes p->tolimit = MINARCS; 1081541Srgrimes else if (p->tolimit > MAXARCS) 1091541Srgrimes p->tolimit = MAXARCS; 1101541Srgrimes p->tossize = p->tolimit * sizeof(struct tostruct); 1111541Srgrimes cp = (char *)malloc(p->kcountsize + p->fromssize + p->tossize, 1121541Srgrimes M_GPROF, M_NOWAIT); 1131541Srgrimes if (cp == 0) { 1141541Srgrimes printf("No memory for profiling.\n"); 1151541Srgrimes return; 1161541Srgrimes } 1171541Srgrimes bzero(cp, p->kcountsize + p->tossize + p->fromssize); 1181541Srgrimes p->tos = (struct tostruct *)cp; 1191541Srgrimes cp += p->tossize; 12013107Sbde p->kcount = (HISTCOUNTER *)cp; 1211541Srgrimes cp += p->kcountsize; 1221541Srgrimes p->froms = (u_short *)cp; 12313107Sbde 12413107Sbde#ifdef GUPROF 12519000Sbde /* Initialize pointers to overhead counters. */ 12613107Sbde p->cputime_count = &KCOUNT(p, PC_TO_I(p, cputime)); 12713107Sbde p->mcount_count = &KCOUNT(p, PC_TO_I(p, mcount)); 12813107Sbde p->mexitcount_count = &KCOUNT(p, PC_TO_I(p, mexitcount)); 12913107Sbde 13013107Sbde /* 13119000Sbde * Disable interrupts to avoid interference while we calibrate 13219000Sbde * things. 13313107Sbde */ 13413107Sbde disable_intr(); 13513107Sbde 13619000Sbde /* 13719000Sbde * Determine overheads. 13819000Sbde * XXX this needs to be repeated for each useful timer/counter. 13919000Sbde */ 14019000Sbde cputime_overhead = 0; 14119000Sbde startguprof(p); 14213107Sbde for (i = 0; i < CALIB_SCALE; i++) 14319000Sbde cputime_overhead += cputime(); 14413107Sbde 14519000Sbde empty_loop(); 14619000Sbde startguprof(p); 14719000Sbde empty_loop(); 14819000Sbde empty_loop_time = cputime(); 14919000Sbde 15019000Sbde nullfunc_loop_profiled(); 15119000Sbde 15219000Sbde /* 15319000Sbde * Start profiling. There won't be any normal function calls since 15419000Sbde * interrupts are disabled, but we will call the profiling routines 15519000Sbde * directly to determine their overheads. 15619000Sbde */ 15719000Sbde p->state = GMON_PROF_HIRES; 15819000Sbde 15919000Sbde startguprof(p); 16019000Sbde nullfunc_loop_profiled(); 16119000Sbde 16219000Sbde startguprof(p); 16313107Sbde for (i = 0; i < CALIB_SCALE; i++) 16435596Sbde#if defined(__i386__) && __GNUC__ >= 2 16535210Sbde __asm("pushl %0; call __mcount; popl %%ecx" 16635210Sbde : 16735210Sbde : "i" (profil) 16835210Sbde : "ax", "bx", "cx", "dx", "memory"); 16913107Sbde#else 17013107Sbde#error 17113107Sbde#endif 17219000Sbde mcount_overhead = KCOUNT(p, PC_TO_I(p, profil)); 17313107Sbde 17419000Sbde startguprof(p); 17513107Sbde for (i = 0; i < CALIB_SCALE; i++) 17635596Sbde#if defined(__i386__) && __GNUC__ >= 2 17735210Sbde __asm("call mexitcount; 1:" 17835210Sbde : : : "ax", "bx", "cx", "dx", "memory"); 17935210Sbde __asm("movl $1b,%0" : "=rm" (tmp_addr)); 18013107Sbde#else 18113107Sbde#error 18213107Sbde#endif 18320396Sbde mexitcount_overhead = KCOUNT(p, PC_TO_I(p, tmp_addr)); 18413107Sbde 18513107Sbde p->state = GMON_PROF_OFF; 18619000Sbde stopguprof(p); 18719000Sbde 18813107Sbde enable_intr(); 18913107Sbde 19019000Sbde nullfunc_loop_profiled_time = 0; 19120396Sbde for (tmp_addr = (fptrint_t)nullfunc_loop_profiled; 19220396Sbde tmp_addr < (fptrint_t)nullfunc_loop_profiled_end; 19320396Sbde tmp_addr += HISTFRACTION * sizeof(HISTCOUNTER)) 19420396Sbde nullfunc_loop_profiled_time += KCOUNT(p, PC_TO_I(p, tmp_addr)); 19519000Sbde#define CALIB_DOSCALE(count) (((count) + CALIB_SCALE / 3) / CALIB_SCALE) 19619000Sbde#define c2n(count, freq) ((int)((count) * 1000000000LL / freq)) 19719000Sbde printf("cputime %d, empty_loop %d, nullfunc_loop_profiled %d, mcount %d, mexitcount %d\n", 19819000Sbde CALIB_DOSCALE(c2n(cputime_overhead, p->profrate)), 19919000Sbde CALIB_DOSCALE(c2n(empty_loop_time, p->profrate)), 20019000Sbde CALIB_DOSCALE(c2n(nullfunc_loop_profiled_time, p->profrate)), 20119000Sbde CALIB_DOSCALE(c2n(mcount_overhead, p->profrate)), 20219000Sbde CALIB_DOSCALE(c2n(mexitcount_overhead, p->profrate))); 20319000Sbde cputime_overhead -= empty_loop_time; 20419000Sbde mcount_overhead -= empty_loop_time; 20519000Sbde mexitcount_overhead -= empty_loop_time; 20619000Sbde 20719000Sbde /*- 20819000Sbde * Profiling overheads are determined by the times between the 20919000Sbde * following events: 21019000Sbde * MC1: mcount() is called 21119000Sbde * MC2: cputime() (called from mcount()) latches the timer 21219000Sbde * MC3: mcount() completes 21319000Sbde * ME1: mexitcount() is called 21419000Sbde * ME2: cputime() (called from mexitcount()) latches the timer 21519000Sbde * ME3: mexitcount() completes. 21619000Sbde * The times between the events vary slightly depending on instruction 21719000Sbde * combination and cache misses, etc. Attempt to determine the 21819000Sbde * minimum times. These can be subtracted from the profiling times 21919000Sbde * without much risk of reducing the profiling times below what they 22019000Sbde * would be when profiling is not configured. Abbreviate: 22119000Sbde * ab = minimum time between MC1 and MC3 22219000Sbde * a = minumum time between MC1 and MC2 22319000Sbde * b = minimum time between MC2 and MC3 22419000Sbde * cd = minimum time between ME1 and ME3 22519000Sbde * c = minimum time between ME1 and ME2 22619000Sbde * d = minimum time between ME2 and ME3. 22719000Sbde * These satisfy the relations: 22819000Sbde * ab <= mcount_overhead (just measured) 22919000Sbde * a + b <= ab 23019000Sbde * cd <= mexitcount_overhead (just measured) 23119000Sbde * c + d <= cd 23219000Sbde * a + d <= nullfunc_loop_profiled_time (just measured) 23319000Sbde * a >= 0, b >= 0, c >= 0, d >= 0. 23419000Sbde * Assume that ab and cd are equal to the minimums. 23519000Sbde */ 23619000Sbde p->cputime_overhead = CALIB_DOSCALE(cputime_overhead); 23719000Sbde p->mcount_overhead = CALIB_DOSCALE(mcount_overhead - cputime_overhead); 23819000Sbde p->mexitcount_overhead = CALIB_DOSCALE(mexitcount_overhead 23919000Sbde - cputime_overhead); 24019000Sbde nullfunc_loop_overhead = nullfunc_loop_profiled_time - empty_loop_time; 24119000Sbde p->mexitcount_post_overhead = CALIB_DOSCALE((mcount_overhead 24219000Sbde - nullfunc_loop_overhead) 24319000Sbde / 4); 24419000Sbde p->mexitcount_pre_overhead = p->mexitcount_overhead 24519000Sbde + p->cputime_overhead 24619000Sbde - p->mexitcount_post_overhead; 24719000Sbde p->mcount_pre_overhead = CALIB_DOSCALE(nullfunc_loop_overhead) 24819000Sbde - p->mexitcount_post_overhead; 24919000Sbde p->mcount_post_overhead = p->mcount_overhead 25019000Sbde + p->cputime_overhead 25119000Sbde - p->mcount_pre_overhead; 25219000Sbde printf( 25319000Sbde"Profiling overheads: mcount: %d+%d, %d+%d; mexitcount: %d+%d, %d+%d nsec\n", 25419000Sbde c2n(p->cputime_overhead, p->profrate), 25519000Sbde c2n(p->mcount_overhead, p->profrate), 25619000Sbde c2n(p->mcount_pre_overhead, p->profrate), 25719000Sbde c2n(p->mcount_post_overhead, p->profrate), 25819000Sbde c2n(p->cputime_overhead, p->profrate), 25919000Sbde c2n(p->mexitcount_overhead, p->profrate), 26019000Sbde c2n(p->mexitcount_pre_overhead, p->profrate), 26119000Sbde c2n(p->mexitcount_post_overhead, p->profrate)); 26219000Sbde printf( 26319000Sbde"Profiling overheads: mcount: %d+%d, %d+%d; mexitcount: %d+%d, %d+%d cycles\n", 26419000Sbde p->cputime_overhead, p->mcount_overhead, 26519000Sbde p->mcount_pre_overhead, p->mcount_post_overhead, 26619000Sbde p->cputime_overhead, p->mexitcount_overhead, 26719000Sbde p->mexitcount_pre_overhead, p->mexitcount_post_overhead); 26813107Sbde#endif /* GUPROF */ 2691541Srgrimes} 2701541Srgrimes 2711541Srgrimes/* 2721541Srgrimes * Return kernel profiling information. 2731541Srgrimes */ 27412429Sphkstatic int 27512429Sphksysctl_kern_prof SYSCTL_HANDLER_ARGS 2761541Srgrimes{ 27712429Sphk int *name = (int *) arg1; 27812429Sphk u_int namelen = arg2; 2791541Srgrimes struct gmonparam *gp = &_gmonparam; 2801541Srgrimes int error; 28113107Sbde int state; 2821541Srgrimes 2831541Srgrimes /* all sysctl names at this level are terminal */ 2841541Srgrimes if (namelen != 1) 2851541Srgrimes return (ENOTDIR); /* overloaded */ 2861541Srgrimes 2871541Srgrimes switch (name[0]) { 2881541Srgrimes case GPROF_STATE: 28913107Sbde state = gp->state; 29013107Sbde error = sysctl_handle_int(oidp, &state, 0, req); 2911541Srgrimes if (error) 2921541Srgrimes return (error); 29313107Sbde if (!req->newptr) 29413107Sbde return (0); 29513107Sbde if (state == GMON_PROF_OFF) { 29619000Sbde gp->state = state; 2971541Srgrimes stopprofclock(&proc0); 29819000Sbde stopguprof(gp); 29913107Sbde } else if (state == GMON_PROF_ON) { 30019000Sbde gp->state = GMON_PROF_OFF; 30119000Sbde stopguprof(gp); 30213107Sbde gp->profrate = profhz; 30319000Sbde startprofclock(&proc0); 30413107Sbde gp->state = state; 30513107Sbde#ifdef GUPROF 30613107Sbde } else if (state == GMON_PROF_HIRES) { 30719000Sbde gp->state = GMON_PROF_OFF; 30813107Sbde stopprofclock(&proc0); 30919000Sbde startguprof(gp); 31013107Sbde gp->state = state; 31113107Sbde#endif 31213107Sbde } else if (state != gp->state) 31313107Sbde return (EINVAL); 3141541Srgrimes return (0); 3151541Srgrimes case GPROF_COUNT: 31612429Sphk return (sysctl_handle_opaque(oidp, 31712429Sphk gp->kcount, gp->kcountsize, req)); 3181541Srgrimes case GPROF_FROMS: 31912429Sphk return (sysctl_handle_opaque(oidp, 32012429Sphk gp->froms, gp->fromssize, req)); 3211541Srgrimes case GPROF_TOS: 32212429Sphk return (sysctl_handle_opaque(oidp, 32312429Sphk gp->tos, gp->tossize, req)); 3241541Srgrimes case GPROF_GMONPARAM: 32512429Sphk return (sysctl_handle_opaque(oidp, gp, sizeof *gp, req)); 3261541Srgrimes default: 3271541Srgrimes return (EOPNOTSUPP); 3281541Srgrimes } 3291541Srgrimes /* NOTREACHED */ 3301541Srgrimes} 33112429Sphk 33212429SphkSYSCTL_NODE(_kern, KERN_PROF, prof, CTLFLAG_RW, sysctl_kern_prof, ""); 3331541Srgrimes#endif /* GPROF */ 3341541Srgrimes 3351541Srgrimes/* 3361541Srgrimes * Profiling system call. 3371541Srgrimes * 3381541Srgrimes * The scale factor is a fixed point number with 16 bits of fraction, so that 3391541Srgrimes * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling. 3401541Srgrimes */ 34112221Sbde#ifndef _SYS_SYSPROTO_H_ 3421541Srgrimesstruct profil_args { 3431541Srgrimes caddr_t samples; 3441541Srgrimes u_int size; 3451541Srgrimes u_int offset; 3461541Srgrimes u_int scale; 3471541Srgrimes}; 34812221Sbde#endif 3491541Srgrimes/* ARGSUSED */ 3501549Srgrimesint 35130994Sphkprofil(p, uap) 3521541Srgrimes struct proc *p; 3531541Srgrimes register struct profil_args *uap; 3541541Srgrimes{ 3551541Srgrimes register struct uprof *upp; 3561541Srgrimes int s; 3571541Srgrimes 3581541Srgrimes if (uap->scale > (1 << 16)) 3591541Srgrimes return (EINVAL); 3601541Srgrimes if (uap->scale == 0) { 3611541Srgrimes stopprofclock(p); 3621541Srgrimes return (0); 3631541Srgrimes } 3641541Srgrimes upp = &p->p_stats->p_prof; 3651541Srgrimes 3661541Srgrimes /* Block profile interrupts while changing state. */ 3671541Srgrimes s = splstatclock(); 3681541Srgrimes upp->pr_off = uap->offset; 3691541Srgrimes upp->pr_scale = uap->scale; 3701541Srgrimes upp->pr_base = uap->samples; 3711541Srgrimes upp->pr_size = uap->size; 3721541Srgrimes startprofclock(p); 3731541Srgrimes splx(s); 3741541Srgrimes 3751541Srgrimes return (0); 3761541Srgrimes} 3771541Srgrimes 3781541Srgrimes/* 3791541Srgrimes * Scale is a fixed-point number with the binary point 16 bits 3801541Srgrimes * into the value, and is <= 1.0. pc is at most 32 bits, so the 3811541Srgrimes * intermediate result is at most 48 bits. 3821541Srgrimes */ 3831541Srgrimes#define PC_TO_INDEX(pc, prof) \ 3841541Srgrimes ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \ 3851541Srgrimes (u_quad_t)((prof)->pr_scale)) >> 16) & ~1) 3861541Srgrimes 3871541Srgrimes/* 3881541Srgrimes * Collect user-level profiling statistics; called on a profiling tick, 3891541Srgrimes * when a process is running in user-mode. This routine may be called 3901541Srgrimes * from an interrupt context. We try to update the user profiling buffers 3911541Srgrimes * cheaply with fuswintr() and suswintr(). If that fails, we revert to 3921541Srgrimes * an AST that will vector us to trap() with a context in which copyin 3931541Srgrimes * and copyout will work. Trap will then call addupc_task(). 3941541Srgrimes * 3951541Srgrimes * Note that we may (rarely) not get around to the AST soon enough, and 3961541Srgrimes * lose profile ticks when the next tick overwrites this one, but in this 3971541Srgrimes * case the system is overloaded and the profile is probably already 3981541Srgrimes * inaccurate. 3991541Srgrimes */ 4001541Srgrimesvoid 4011541Srgrimesaddupc_intr(p, pc, ticks) 4021541Srgrimes register struct proc *p; 4031541Srgrimes register u_long pc; 4041541Srgrimes u_int ticks; 4051541Srgrimes{ 4061541Srgrimes register struct uprof *prof; 4071541Srgrimes register caddr_t addr; 4081541Srgrimes register u_int i; 4091541Srgrimes register int v; 4101541Srgrimes 4111541Srgrimes if (ticks == 0) 4121541Srgrimes return; 4131541Srgrimes prof = &p->p_stats->p_prof; 4141541Srgrimes if (pc < prof->pr_off || 4151541Srgrimes (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 4161541Srgrimes return; /* out of range; ignore */ 4171541Srgrimes 4181541Srgrimes addr = prof->pr_base + i; 4191541Srgrimes if ((v = fuswintr(addr)) == -1 || suswintr(addr, v + ticks) == -1) { 4201541Srgrimes prof->pr_addr = pc; 4211541Srgrimes prof->pr_ticks = ticks; 4221541Srgrimes need_proftick(p); 4231541Srgrimes } 4241541Srgrimes} 4251541Srgrimes 4261541Srgrimes/* 4271541Srgrimes * Much like before, but we can afford to take faults here. If the 4281541Srgrimes * update fails, we simply turn off profiling. 4291541Srgrimes */ 43013017Sbdevoid 4311541Srgrimesaddupc_task(p, pc, ticks) 4321541Srgrimes register struct proc *p; 4331541Srgrimes register u_long pc; 4341541Srgrimes u_int ticks; 4351541Srgrimes{ 4361541Srgrimes register struct uprof *prof; 4371541Srgrimes register caddr_t addr; 4381541Srgrimes register u_int i; 4391541Srgrimes u_short v; 4401541Srgrimes 4411541Srgrimes /* Testing P_PROFIL may be unnecessary, but is certainly safe. */ 4421541Srgrimes if ((p->p_flag & P_PROFIL) == 0 || ticks == 0) 4431541Srgrimes return; 4441541Srgrimes 4451541Srgrimes prof = &p->p_stats->p_prof; 4461541Srgrimes if (pc < prof->pr_off || 4471541Srgrimes (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 4481541Srgrimes return; 4491541Srgrimes 4501541Srgrimes addr = prof->pr_base + i; 4511541Srgrimes if (copyin(addr, (caddr_t)&v, sizeof(v)) == 0) { 4521541Srgrimes v += ticks; 4531541Srgrimes if (copyout((caddr_t)&v, addr, sizeof(v)) == 0) 4541541Srgrimes return; 4551541Srgrimes } 4561541Srgrimes stopprofclock(p); 4571541Srgrimes} 458