1 /* $NetBSD: subr_prof.c,v 1.5 1995/03/19 23:44:54 mycroft Exp $ */ 2 3 /*- 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)subr_prof.c 8.3 (Berkeley) 9/23/93 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/proc.h> 42 #include <sys/user.h> 43 44 #include <sys/mount.h> 45 #include <sys/syscallargs.h> 46 47 #include <machine/cpu.h> 48 49 #ifdef GPROF 50 #include <sys/malloc.h> 51 #include <sys/gmon.h> 52 53 /* 54 * Froms is actually a bunch of unsigned shorts indexing tos 55 */ 56 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 57 58 extern char etext[]; 59 60 kmstartup() 61 { 62 char *cp; 63 struct gmonparam *p = &_gmonparam; 64 /* 65 * Round lowpc and highpc to multiples of the density we're using 66 * so the rest of the scaling (here and in gprof) stays in ints. 67 */ 68 p->lowpc = ROUNDDOWN(KERNBASE, HISTFRACTION * sizeof(HISTCOUNTER)); 69 p->highpc = ROUNDUP((u_long)etext, HISTFRACTION * sizeof(HISTCOUNTER)); 70 p->textsize = p->highpc - p->lowpc; 71 printf("Profiling kernel, textsize=%d [%p..%p]\n", 72 p->textsize, p->lowpc, p->highpc); 73 p->kcountsize = p->textsize / HISTFRACTION; 74 p->hashfraction = HASHFRACTION; 75 p->fromssize = p->textsize / HASHFRACTION; 76 p->tolimit = p->textsize * ARCDENSITY / 100; 77 if (p->tolimit < MINARCS) 78 p->tolimit = MINARCS; 79 else if (p->tolimit > MAXARCS) 80 p->tolimit = MAXARCS; 81 p->tossize = p->tolimit * sizeof(struct tostruct); 82 cp = (char *)malloc(p->kcountsize + p->fromssize + p->tossize, 83 M_GPROF, M_NOWAIT); 84 if (cp == 0) { 85 printf("No memory for profiling.\n"); 86 return; 87 } 88 bzero(cp, p->kcountsize + p->tossize + p->fromssize); 89 p->tos = (struct tostruct *)cp; 90 cp += p->tossize; 91 p->kcount = (u_short *)cp; 92 cp += p->kcountsize; 93 p->froms = (u_short *)cp; 94 } 95 96 /* 97 * Return kernel profiling information. 98 */ 99 sysctl_doprof(name, namelen, oldp, oldlenp, newp, newlen, p) 100 int *name; 101 u_int namelen; 102 void *oldp; 103 size_t *oldlenp; 104 void *newp; 105 size_t newlen; 106 { 107 struct gmonparam *gp = &_gmonparam; 108 int error; 109 110 /* all sysctl names at this level are terminal */ 111 if (namelen != 1) 112 return (ENOTDIR); /* overloaded */ 113 114 switch (name[0]) { 115 case GPROF_STATE: 116 error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state); 117 if (error) 118 return (error); 119 if (gp->state == GMON_PROF_OFF) 120 stopprofclock(&proc0); 121 else 122 startprofclock(&proc0); 123 return (0); 124 case GPROF_COUNT: 125 return (sysctl_struct(oldp, oldlenp, newp, newlen, 126 gp->kcount, gp->kcountsize)); 127 case GPROF_FROMS: 128 return (sysctl_struct(oldp, oldlenp, newp, newlen, 129 gp->froms, gp->fromssize)); 130 case GPROF_TOS: 131 return (sysctl_struct(oldp, oldlenp, newp, newlen, 132 gp->tos, gp->tossize)); 133 case GPROF_GMONPARAM: 134 return (sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp)); 135 default: 136 return (EOPNOTSUPP); 137 } 138 /* NOTREACHED */ 139 } 140 #endif /* GPROF */ 141 142 /* 143 * Profiling system call. 144 * 145 * The scale factor is a fixed point number with 16 bits of fraction, so that 146 * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling. 147 */ 148 /* ARGSUSED */ 149 profil(p, uap, retval) 150 struct proc *p; 151 register struct profil_args /* { 152 syscallarg(caddr_t) samples; 153 syscallarg(u_int) size; 154 syscallarg(u_int) offset; 155 syscallarg(u_int) scale; 156 } */ *uap; 157 register_t *retval; 158 { 159 register struct uprof *upp; 160 int s; 161 162 if (SCARG(uap, scale) > (1 << 16)) 163 return (EINVAL); 164 if (SCARG(uap, scale) == 0) { 165 stopprofclock(p); 166 return (0); 167 } 168 upp = &p->p_stats->p_prof; 169 170 /* Block profile interrupts while changing state. */ 171 s = splstatclock(); 172 upp->pr_off = SCARG(uap, offset); 173 upp->pr_scale = SCARG(uap, scale); 174 upp->pr_base = SCARG(uap, samples); 175 upp->pr_size = SCARG(uap, size); 176 startprofclock(p); 177 splx(s); 178 179 return (0); 180 } 181 182 /* 183 * Scale is a fixed-point number with the binary point 16 bits 184 * into the value, and is <= 1.0. pc is at most 32 bits, so the 185 * intermediate result is at most 48 bits. 186 */ 187 #define PC_TO_INDEX(pc, prof) \ 188 ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \ 189 (u_quad_t)((prof)->pr_scale)) >> 16) & ~1) 190 191 /* 192 * Collect user-level profiling statistics; called on a profiling tick, 193 * when a process is running in user-mode. This routine may be called 194 * from an interrupt context. We try to update the user profiling buffers 195 * cheaply with fuswintr() and suswintr(). If that fails, we revert to 196 * an AST that will vector us to trap() with a context in which copyin 197 * and copyout will work. Trap will then call addupc_task(). 198 * 199 * Note that we may (rarely) not get around to the AST soon enough, and 200 * lose profile ticks when the next tick overwrites this one, but in this 201 * case the system is overloaded and the profile is probably already 202 * inaccurate. 203 */ 204 void 205 addupc_intr(p, pc, ticks) 206 register struct proc *p; 207 register u_long pc; 208 u_int ticks; 209 { 210 register struct uprof *prof; 211 register caddr_t addr; 212 register u_int i; 213 register int v; 214 215 if (ticks == 0) 216 return; 217 prof = &p->p_stats->p_prof; 218 if (pc < prof->pr_off || 219 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 220 return; /* out of range; ignore */ 221 222 addr = prof->pr_base + i; 223 if ((v = fuswintr(addr)) == -1 || suswintr(addr, v + ticks) == -1) { 224 prof->pr_addr = pc; 225 prof->pr_ticks = ticks; 226 need_proftick(p); 227 } 228 } 229 230 /* 231 * Much like before, but we can afford to take faults here. If the 232 * update fails, we simply turn off profiling. 233 */ 234 void 235 addupc_task(p, pc, ticks) 236 register struct proc *p; 237 register u_long pc; 238 u_int ticks; 239 { 240 register struct uprof *prof; 241 register caddr_t addr; 242 register u_int i; 243 u_short v; 244 245 /* Testing P_PROFIL may be unnecessary, but is certainly safe. */ 246 if ((p->p_flag & P_PROFIL) == 0 || ticks == 0) 247 return; 248 249 prof = &p->p_stats->p_prof; 250 if (pc < prof->pr_off || 251 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 252 return; 253 254 addr = prof->pr_base + i; 255 if (copyin(addr, (caddr_t)&v, sizeof(v)) == 0) { 256 v += ticks; 257 if (copyout((caddr_t)&v, addr, sizeof(v)) == 0) 258 return; 259 } 260 stopprofclock(p); 261 } 262