1 /* $OpenBSD: subr_prof.c,v 1.8 2001/09/19 20:50:59 mickey Exp $ */ 2 /* $NetBSD: subr_prof.c,v 1.12 1996/04/22 01:38:50 christos Exp $ */ 3 4 /*- 5 * Copyright (c) 1982, 1986, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)subr_prof.c 8.3 (Berkeley) 9/23/93 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #include <sys/proc.h> 43 #include <sys/user.h> 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 #include <vm/vm.h> 53 #include <uvm/uvm_extern.h> 54 55 /* 56 * Froms is actually a bunch of unsigned shorts indexing tos 57 */ 58 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 59 60 extern char etext[]; 61 62 63 void 64 kmstartup() 65 { 66 char *cp; 67 struct gmonparam *p = &_gmonparam; 68 int size; 69 70 /* 71 * Round lowpc and highpc to multiples of the density we're using 72 * so the rest of the scaling (here and in gprof) stays in ints. 73 */ 74 p->lowpc = ROUNDDOWN(KERNBASE, HISTFRACTION * sizeof(HISTCOUNTER)); 75 p->highpc = ROUNDUP((u_long)etext, HISTFRACTION * sizeof(HISTCOUNTER)); 76 p->textsize = p->highpc - p->lowpc; 77 printf("Profiling kernel, textsize=%ld [%lx..%lx]\n", 78 p->textsize, p->lowpc, p->highpc); 79 p->kcountsize = p->textsize / HISTFRACTION; 80 p->hashfraction = HASHFRACTION; 81 p->fromssize = p->textsize / HASHFRACTION; 82 p->tolimit = p->textsize * ARCDENSITY / 100; 83 if (p->tolimit < MINARCS) 84 p->tolimit = MINARCS; 85 else if (p->tolimit > MAXARCS) 86 p->tolimit = MAXARCS; 87 p->tossize = p->tolimit * sizeof(struct tostruct); 88 size = p->kcountsize + p->fromssize + p->tossize; 89 cp = (char *)uvm_km_zalloc(kernel_map, round_page(size)); 90 if (cp == 0) { 91 printf("No memory for profiling.\n"); 92 return; 93 } 94 p->tos = (struct tostruct *)cp; 95 cp += p->tossize; 96 p->kcount = (u_short *)cp; 97 cp += p->kcountsize; 98 p->froms = (u_short *)cp; 99 } 100 101 /* 102 * Return kernel profiling information. 103 */ 104 int 105 sysctl_doprof(name, namelen, oldp, oldlenp, newp, newlen) 106 int *name; 107 u_int namelen; 108 void *oldp; 109 size_t *oldlenp; 110 void *newp; 111 size_t newlen; 112 { 113 struct gmonparam *gp = &_gmonparam; 114 int error; 115 116 /* all sysctl names at this level are terminal */ 117 if (namelen != 1) 118 return (ENOTDIR); /* overloaded */ 119 120 switch (name[0]) { 121 case GPROF_STATE: 122 error = sysctl_int(oldp, oldlenp, newp, newlen, &gp->state); 123 if (error) 124 return (error); 125 if (gp->state == GMON_PROF_OFF) 126 stopprofclock(&proc0); 127 else 128 startprofclock(&proc0); 129 return (0); 130 case GPROF_COUNT: 131 return (sysctl_struct(oldp, oldlenp, newp, newlen, 132 gp->kcount, gp->kcountsize)); 133 case GPROF_FROMS: 134 return (sysctl_struct(oldp, oldlenp, newp, newlen, 135 gp->froms, gp->fromssize)); 136 case GPROF_TOS: 137 return (sysctl_struct(oldp, oldlenp, newp, newlen, 138 gp->tos, gp->tossize)); 139 case GPROF_GMONPARAM: 140 return (sysctl_rdstruct(oldp, oldlenp, newp, gp, sizeof *gp)); 141 default: 142 return (EOPNOTSUPP); 143 } 144 /* NOTREACHED */ 145 } 146 #endif /* GPROF */ 147 148 /* 149 * Profiling system call. 150 * 151 * The scale factor is a fixed point number with 16 bits of fraction, so that 152 * 1.0 is represented as 0x10000. A scale factor of 0 turns off profiling. 153 */ 154 /* ARGSUSED */ 155 int 156 sys_profil(p, v, retval) 157 struct proc *p; 158 void *v; 159 register_t *retval; 160 { 161 register struct sys_profil_args /* { 162 syscallarg(char *) samples; 163 syscallarg(u_int) size; 164 syscallarg(u_int) offset; 165 syscallarg(u_int) scale; 166 } */ *uap = v; 167 register struct uprof *upp; 168 int s; 169 170 if (SCARG(uap, scale) > (1 << 16)) 171 return (EINVAL); 172 if (SCARG(uap, scale) == 0) { 173 stopprofclock(p); 174 return (0); 175 } 176 upp = &p->p_stats->p_prof; 177 178 /* Block profile interrupts while changing state. */ 179 s = splstatclock(); 180 upp->pr_off = SCARG(uap, offset); 181 upp->pr_scale = SCARG(uap, scale); 182 upp->pr_base = (caddr_t)SCARG(uap, samples); 183 upp->pr_size = SCARG(uap, size); 184 startprofclock(p); 185 splx(s); 186 187 return (0); 188 } 189 190 /* 191 * Scale is a fixed-point number with the binary point 16 bits 192 * into the value, and is <= 1.0. pc is at most 32 bits, so the 193 * intermediate result is at most 48 bits. 194 */ 195 #define PC_TO_INDEX(pc, prof) \ 196 ((int)(((u_quad_t)((pc) - (prof)->pr_off) * \ 197 (u_quad_t)((prof)->pr_scale)) >> 16) & ~1) 198 199 /* 200 * Collect user-level profiling statistics; called on a profiling tick, 201 * when a process is running in user-mode. This routine may be called 202 * from an interrupt context. We try to update the user profiling buffers 203 * cheaply with fuswintr() and suswintr(). If that fails, we revert to 204 * an AST that will vector us to trap() with a context in which copyin 205 * and copyout will work. Trap will then call addupc_task(). 206 * 207 * Note that we may (rarely) not get around to the AST soon enough, and 208 * lose profile ticks when the next tick overwrites this one, but in this 209 * case the system is overloaded and the profile is probably already 210 * inaccurate. 211 */ 212 void 213 addupc_intr(p, pc, ticks) 214 register struct proc *p; 215 register u_long pc; 216 u_int ticks; 217 { 218 register struct uprof *prof; 219 register caddr_t addr; 220 register u_int i; 221 register int v; 222 223 if (ticks == 0) 224 return; 225 prof = &p->p_stats->p_prof; 226 if (pc < prof->pr_off || 227 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 228 return; /* out of range; ignore */ 229 230 addr = prof->pr_base + i; 231 if ((v = fuswintr(addr)) == -1 || suswintr(addr, v + ticks) == -1) { 232 prof->pr_addr = pc; 233 prof->pr_ticks = ticks; 234 need_proftick(p); 235 } 236 } 237 238 /* 239 * Much like before, but we can afford to take faults here. If the 240 * update fails, we simply turn off profiling. 241 */ 242 void 243 addupc_task(p, pc, ticks) 244 register struct proc *p; 245 register u_long pc; 246 u_int ticks; 247 { 248 register struct uprof *prof; 249 register caddr_t addr; 250 register u_int i; 251 u_short v; 252 253 /* Testing P_PROFIL may be unnecessary, but is certainly safe. */ 254 if ((p->p_flag & P_PROFIL) == 0 || ticks == 0) 255 return; 256 257 prof = &p->p_stats->p_prof; 258 if (pc < prof->pr_off || 259 (i = PC_TO_INDEX(pc, prof)) >= prof->pr_size) 260 return; 261 262 addr = prof->pr_base + i; 263 if (copyin(addr, (caddr_t)&v, sizeof(v)) == 0) { 264 v += ticks; 265 if (copyout((caddr_t)&v, addr, sizeof(v)) == 0) 266 return; 267 } 268 stopprofclock(p); 269 } 270