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