1 /* $NetBSD: subr_prof.c,v 1.14 1996/10/13 02:32:40 christos 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 #include <sys/mount.h> 44 #include <sys/syscallargs.h> 45 46 #include <machine/cpu.h> 47 48 #ifdef GPROF 49 #include <sys/malloc.h> 50 #include <sys/gmon.h> 51 52 /* 53 * Froms is actually a bunch of unsigned shorts indexing tos 54 */ 55 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 56 57 extern char etext[]; 58 59 60 void 61 kmstartup() 62 { 63 char *cp; 64 struct gmonparam *p = &_gmonparam; 65 /* 66 * Round lowpc and highpc to multiples of the density we're using 67 * so the rest of the scaling (here and in gprof) stays in ints. 68 */ 69 p->lowpc = ROUNDDOWN(KERNBASE, HISTFRACTION * sizeof(HISTCOUNTER)); 70 p->highpc = ROUNDUP((u_long)etext, HISTFRACTION * sizeof(HISTCOUNTER)); 71 p->textsize = p->highpc - p->lowpc; 72 printf("Profiling kernel, textsize=%ld [%lx..%lx]\n", 73 p->textsize, p->lowpc, p->highpc); 74 p->kcountsize = p->textsize / HISTFRACTION; 75 p->hashfraction = HASHFRACTION; 76 p->fromssize = p->textsize / HASHFRACTION; 77 p->tolimit = p->textsize * ARCDENSITY / 100; 78 if (p->tolimit < MINARCS) 79 p->tolimit = MINARCS; 80 else if (p->tolimit > MAXARCS) 81 p->tolimit = MAXARCS; 82 p->tossize = p->tolimit * sizeof(struct tostruct); 83 cp = (char *)malloc(p->kcountsize + p->fromssize + p->tossize, 84 M_GPROF, M_NOWAIT); 85 if (cp == 0) { 86 printf("No memory for profiling.\n"); 87 return; 88 } 89 bzero(cp, p->kcountsize + p->tossize + p->fromssize); 90 p->tos = (struct tostruct *)cp; 91 cp += p->tossize; 92 p->kcount = (u_short *)cp; 93 cp += p->kcountsize; 94 p->froms = (u_short *)cp; 95 } 96 97 /* 98 * Return kernel profiling information. 99 */ 100 int 101 sysctl_doprof(name, namelen, oldp, oldlenp, newp, newlen) 102 int *name; 103 u_int namelen; 104 void *oldp; 105 size_t *oldlenp; 106 void *newp; 107 size_t newlen; 108 { 109 struct gmonparam *gp = &_gmonparam; 110 int error; 111 112 /* all sysctl names at this level are terminal */ 113 if (namelen != 1) 114 return (ENOTDIR); /* overloaded */ 115 116 switch (name[0]) { 117 case GPROF_STATE: 118 error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state); 119 if (error) 120 return (error); 121 if (gp->state == GMON_PROF_OFF) 122 stopprofclock(&proc0); 123 else 124 startprofclock(&proc0); 125 return (0); 126 case GPROF_COUNT: 127 return (sysctl_struct(oldp, oldlenp, newp, newlen, 128 gp->kcount, gp->kcountsize)); 129 case GPROF_FROMS: 130 return (sysctl_struct(oldp, oldlenp, newp, newlen, 131 gp->froms, gp->fromssize)); 132 case GPROF_TOS: 133 return (sysctl_struct(oldp, oldlenp, newp, newlen, 134 gp->tos, gp->tossize)); 135 case GPROF_GMONPARAM: 136 return (sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp)); 137 default: 138 return (EOPNOTSUPP); 139 } 140 /* NOTREACHED */ 141 } 142 #endif /* GPROF */ 143 144 /* 145 * Profiling system call. 146 * 147 * The scale factor is a fixed point number with 16 bits of fraction, so that 148 * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling. 149 */ 150 /* ARGSUSED */ 151 int 152 sys_profil(p, v, retval) 153 struct proc *p; 154 void *v; 155 register_t *retval; 156 { 157 register struct sys_profil_args /* { 158 syscallarg(caddr_t) samples; 159 syscallarg(u_int) size; 160 syscallarg(u_int) offset; 161 syscallarg(u_int) scale; 162 } */ *uap = v; 163 register struct uprof *upp; 164 int s; 165 166 if (SCARG(uap, scale) > (1 << 16)) 167 return (EINVAL); 168 if (SCARG(uap, scale) == 0) { 169 stopprofclock(p); 170 return (0); 171 } 172 upp = &p->p_stats->p_prof; 173 174 /* Block profile interrupts while changing state. */ 175 s = splstatclock(); 176 upp->pr_off = SCARG(uap, offset); 177 upp->pr_scale = SCARG(uap, scale); 178 upp->pr_base = SCARG(uap, samples); 179 upp->pr_size = SCARG(uap, size); 180 startprofclock(p); 181 splx(s); 182 183 return (0); 184 } 185 186 /* 187 * Scale is a fixed-point number with the binary point 16 bits 188 * into the value, and is <= 1.0. pc is at most 32 bits, so the 189 * intermediate result is at most 48 bits. 190 */ 191 #define PC_TO_INDEX(pc, prof) \ 192 ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \ 193 (u_quad_t)((prof)->pr_scale)) >> 16) & ~1) 194 195 /* 196 * Collect user-level profiling statistics; called on a profiling tick, 197 * when a process is running in user-mode. This routine may be called 198 * from an interrupt context. We try to update the user profiling buffers 199 * cheaply with fuswintr() and suswintr(). If that fails, we revert to 200 * an AST that will vector us to trap() with a context in which copyin 201 * and copyout will work. Trap will then call addupc_task(). 202 * 203 * Note that we may (rarely) not get around to the AST soon enough, and 204 * lose profile ticks when the next tick overwrites this one, but in this 205 * case the system is overloaded and the profile is probably already 206 * inaccurate. 207 */ 208 void 209 addupc_intr(p, pc, ticks) 210 register struct proc *p; 211 register u_long pc; 212 u_int ticks; 213 { 214 register struct uprof *prof; 215 register caddr_t addr; 216 register u_int i; 217 register int v; 218 219 if (ticks == 0) 220 return; 221 prof = &p->p_stats->p_prof; 222 if (pc < prof->pr_off || 223 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 224 return; /* out of range; ignore */ 225 226 addr = prof->pr_base + i; 227 if ((v = fuswintr(addr)) == -1 || suswintr(addr, v + ticks) == -1) { 228 prof->pr_addr = pc; 229 prof->pr_ticks = ticks; 230 need_proftick(p); 231 } 232 } 233 234 /* 235 * Much like before, but we can afford to take faults here. If the 236 * update fails, we simply turn off profiling. 237 */ 238 void 239 addupc_task(p, pc, ticks) 240 register struct proc *p; 241 register u_long pc; 242 u_int ticks; 243 { 244 register struct uprof *prof; 245 register caddr_t addr; 246 register u_int i; 247 u_short v; 248 249 /* Testing P_PROFIL may be unnecessary, but is certainly safe. */ 250 if ((p->p_flag & P_PROFIL) == 0 || ticks == 0) 251 return; 252 253 prof = &p->p_stats->p_prof; 254 if (pc < prof->pr_off || 255 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 256 return; 257 258 addr = prof->pr_base + i; 259 if (copyin(addr, (caddr_t)&v, sizeof(v)) == 0) { 260 v += ticks; 261 if (copyout((caddr_t)&v, addr, sizeof(v)) == 0) 262 return; 263 } 264 stopprofclock(p); 265 } 266