1 /* $NetBSD: mcount.c,v 1.18 2024/02/23 13:32:28 christos Exp $ */ 2 3 /* 4 * Copyright (c) 2003, 2004 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Nathan J. Williams for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /*- 39 * Copyright (c) 1983, 1992, 1993 40 * The Regents of the University of California. All rights reserved. 41 * 42 * Redistribution and use in source and binary forms, with or without 43 * modification, are permitted provided that the following conditions 44 * are met: 45 * 1. Redistributions of source code must retain the above copyright 46 * notice, this list of conditions and the following disclaimer. 47 * 2. Redistributions in binary form must reproduce the above copyright 48 * notice, this list of conditions and the following disclaimer in the 49 * documentation and/or other materials provided with the distribution. 50 * 3. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 */ 66 67 #ifdef _KERNEL_OPT 68 #include "opt_multiprocessor.h" 69 #endif 70 71 /* If building a standalone libkern, don't include mcount. */ 72 #if (!defined(_KERNEL) || defined(GPROF)) && !defined(_STANDALONE) 73 74 #include <sys/cdefs.h> 75 #if !defined(lint) && !defined(_KERNEL) && defined(LIBC_SCCS) 76 #if 0 77 static char sccsid[] = "@(#)mcount.c 8.1 (Berkeley) 6/4/93"; 78 #else 79 __RCSID("$NetBSD: mcount.c,v 1.18 2024/02/23 13:32:28 christos Exp $"); 80 #endif 81 #endif 82 83 #include <sys/param.h> 84 #include <sys/gmon.h> 85 #include <sys/lock.h> 86 #include <sys/proc.h> 87 88 #ifndef _KERNEL 89 #include "reentrant.h" 90 #endif 91 92 #if defined(_REENTRANT) && !defined(_RUMPKERNEL) 93 extern thread_key_t _gmonkey; 94 extern struct gmonparam _gmondummy; 95 struct gmonparam *_m_gmon_alloc(void); 96 #endif 97 98 _MCOUNT_DECL(u_long, u_long) 99 #ifdef _KERNEL 100 __attribute__((__no_instrument_function__)) 101 #endif 102 __used; 103 104 /* XXX: make these interfaces */ 105 #ifdef _RUMPKERNEL 106 #undef MCOUNT_ENTER 107 #define MCOUNT_ENTER 108 #undef MCOUNT_EXIT 109 #define MCOUNT_EXIT 110 #undef MCOUNT 111 #define MCOUNT 112 #endif 113 114 /* 115 * mcount is called on entry to each function compiled with the profiling 116 * switch set. _mcount(), which is declared in a machine-dependent way 117 * with _MCOUNT_DECL, does the actual work and is either inlined into a 118 * C routine or called by an assembly stub. In any case, this magic is 119 * taken care of by the MCOUNT definition in <machine/profile.h>. 120 * 121 * _mcount updates data structures that represent traversals of the 122 * program's call graph edges. frompc and selfpc are the return 123 * address and function address that represents the given call graph edge. 124 * 125 * Note: the original BSD code used the same variable (frompcindex) for 126 * both frompcindex and frompc. Any reasonable, modern compiler will 127 * perform this optimization. 128 */ 129 /* _mcount; may be static, inline, etc */ 130 /*LINTED unused*/ 131 _MCOUNT_DECL(u_long frompc, u_long selfpc) 132 { 133 u_short *frompcindex; 134 struct tostruct *top, *prevtop; 135 struct gmonparam *p; 136 long toindex; 137 #if defined(_KERNEL) && !defined(_RUMPKERNEL) 138 int s; 139 #endif 140 141 #if defined(_REENTRANT) && !defined(_KERNEL) && !defined(_RUMPKERNEL) 142 if (__isthreaded) { 143 /* prevent re-entry via thr_getspecific */ 144 if (_gmonparam.state != GMON_PROF_ON) 145 return; 146 _gmonparam.state = GMON_PROF_BUSY; 147 p = thr_getspecific(_gmonkey); 148 if (p == NULL) { 149 /* Prevent recursive calls while allocating */ 150 thr_setspecific(_gmonkey, &_gmondummy); 151 p = _m_gmon_alloc(); 152 } 153 _gmonparam.state = GMON_PROF_ON; 154 } else 155 #endif 156 p = &_gmonparam; 157 /* 158 * check that we are profiling 159 * and that we aren't recursively invoked. 160 */ 161 if (p->state != GMON_PROF_ON) 162 return; 163 #if defined(_KERNEL) && !defined(_RUMPKERNEL) 164 MCOUNT_ENTER; 165 #ifdef MULTIPROCESSOR 166 p = curcpu()->ci_gmon; 167 if (p == NULL || p->state != GMON_PROF_ON) { 168 MCOUNT_EXIT; 169 return; 170 } 171 #endif 172 #endif 173 p->state = GMON_PROF_BUSY; 174 /* 175 * check that frompcindex is a reasonable pc value. 176 * for example: signal catchers get called from the stack, 177 * not from text space. too bad. 178 */ 179 frompc -= p->lowpc; 180 if (frompc > p->textsize) 181 goto done; 182 183 #if (HASHFRACTION & (HASHFRACTION - 1)) == 0 184 if (p->hashfraction == HASHFRACTION) 185 frompcindex = 186 &p->froms[ 187 (size_t)(frompc / (HASHFRACTION * sizeof(*p->froms)))]; 188 else 189 #endif 190 frompcindex = 191 &p->froms[ 192 (size_t)(frompc / (p->hashfraction * sizeof(*p->froms)))]; 193 toindex = *frompcindex; 194 if (toindex == 0) { 195 /* 196 * first time traversing this arc 197 */ 198 toindex = ++p->tos[0].link; 199 if (toindex >= p->tolimit) 200 /* halt further profiling */ 201 goto overflow; 202 203 *frompcindex = (u_short)toindex; 204 top = &p->tos[(size_t)toindex]; 205 top->selfpc = selfpc; 206 top->count = 1; 207 top->link = 0; 208 goto done; 209 } 210 top = &p->tos[(size_t)toindex]; 211 if (top->selfpc == selfpc) { 212 /* 213 * arc at front of chain; usual case. 214 */ 215 top->count++; 216 goto done; 217 } 218 /* 219 * have to go looking down chain for it. 220 * top points to what we are looking at, 221 * prevtop points to previous top. 222 * we know it is not at the head of the chain. 223 */ 224 for (; /* goto done */; ) { 225 if (top->link == 0) { 226 /* 227 * top is end of the chain and none of the chain 228 * had top->selfpc == selfpc. 229 * so we allocate a new tostruct 230 * and link it to the head of the chain. 231 */ 232 toindex = ++p->tos[0].link; 233 if (toindex >= p->tolimit) 234 goto overflow; 235 236 top = &p->tos[(size_t)toindex]; 237 top->selfpc = selfpc; 238 top->count = 1; 239 top->link = *frompcindex; 240 *frompcindex = (u_short)toindex; 241 goto done; 242 } 243 /* 244 * otherwise, check the next arc on the chain. 245 */ 246 prevtop = top; 247 top = &p->tos[top->link]; 248 if (top->selfpc == selfpc) { 249 /* 250 * there it is. 251 * increment its count 252 * move it to the head of the chain. 253 */ 254 top->count++; 255 toindex = prevtop->link; 256 prevtop->link = top->link; 257 top->link = *frompcindex; 258 *frompcindex = (u_short)toindex; 259 goto done; 260 } 261 } 262 done: 263 p->state = GMON_PROF_ON; 264 #if defined(_KERNEL) && !defined(_RUMPKERNEL) 265 MCOUNT_EXIT; 266 #endif 267 return; 268 269 overflow: 270 p->state = GMON_PROF_ERROR; 271 #if defined(_KERNEL) && !defined(_RUMPKERNEL) 272 MCOUNT_EXIT; 273 #endif 274 return; 275 } 276 277 #ifdef MCOUNT 278 /* 279 * Actual definition of mcount function. Defined in <machine/profile.h>, 280 * which is included by <sys/gmon.h>. 281 */ 282 MCOUNT 283 #endif 284 285 #if defined(_KERNEL) && !defined(_RUMPKERNEL) && defined(MULTIPROCESSOR) 286 void _gmonparam_merge(struct gmonparam *, struct gmonparam *); 287 288 void 289 _gmonparam_merge(struct gmonparam *p, struct gmonparam *q) 290 { 291 u_long fromindex; 292 u_short *frompcindex, qtoindex, toindex; 293 u_long selfpc; 294 u_long endfrom; 295 long count; 296 struct tostruct *top; 297 int i; 298 299 count = q->kcountsize / sizeof(*q->kcount); 300 for (i = 0; i < count; i++) 301 p->kcount[i] += q->kcount[i]; 302 303 endfrom = (q->fromssize / sizeof(*q->froms)); 304 for (fromindex = 0; fromindex < endfrom; fromindex++) { 305 if (q->froms[fromindex] == 0) 306 continue; 307 for (qtoindex = q->froms[fromindex]; qtoindex != 0; 308 qtoindex = q->tos[qtoindex].link) { 309 selfpc = q->tos[qtoindex].selfpc; 310 count = q->tos[qtoindex].count; 311 /* cribbed from mcount */ 312 frompcindex = &p->froms[fromindex]; 313 toindex = *frompcindex; 314 if (toindex == 0) { 315 /* 316 * first time traversing this arc 317 */ 318 toindex = ++p->tos[0].link; 319 if (toindex >= p->tolimit) 320 /* halt further profiling */ 321 goto overflow; 322 323 *frompcindex = (u_short)toindex; 324 top = &p->tos[(size_t)toindex]; 325 top->selfpc = selfpc; 326 top->count = count; 327 top->link = 0; 328 goto done; 329 } 330 top = &p->tos[(size_t)toindex]; 331 if (top->selfpc == selfpc) { 332 /* 333 * arc at front of chain; usual case. 334 */ 335 top->count+= count; 336 goto done; 337 } 338 /* 339 * have to go looking down chain for it. 340 * top points to what we are looking at, 341 * we know it is not at the head of the chain. 342 */ 343 for (; /* goto done */; ) { 344 if (top->link == 0) { 345 /* 346 * top is end of the chain and 347 * none of the chain had 348 * top->selfpc == selfpc. so 349 * we allocate a new tostruct 350 * and link it to the head of 351 * the chain. 352 */ 353 toindex = ++p->tos[0].link; 354 if (toindex >= p->tolimit) 355 goto overflow; 356 357 top = &p->tos[(size_t)toindex]; 358 top->selfpc = selfpc; 359 top->count = count; 360 top->link = *frompcindex; 361 *frompcindex = (u_short)toindex; 362 goto done; 363 } 364 /* 365 * otherwise, check the next arc on the chain. 366 */ 367 top = &p->tos[top->link]; 368 if (top->selfpc == selfpc) { 369 /* 370 * there it is. 371 * add to its count. 372 */ 373 top->count += count; 374 goto done; 375 } 376 } 377 378 done: ; 379 } 380 381 } 382 overflow: ; 383 384 } 385 #endif 386 387 #endif /* (!_KERNEL || GPROF) && !_STANDALONE */ 388
Indexes created Sat Sep 20 22:09:52 GMT 2025