subr_evcnt.c revision 1.16
1 /* $NetBSD: subr_evcnt.c,v 1.16 2021/04/15 00:37:31 rin Exp $ */ 2 3 /* 4 * Copyright (c) 1996, 2000 Christopher G. Demetriou 5 * 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 for the 18 * NetBSD Project. See http://www.NetBSD.org/ for 19 * information about NetBSD. 20 * 4. The name of the author may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 26 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 28 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 32 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 * 34 * --(license Id: LICENSE.proto,v 1.1 2000/06/13 21:40:26 cgd Exp )-- 35 */ 36 37 /* 38 * Copyright (c) 1992, 1993 39 * The Regents of the University of California. All rights reserved. 40 * 41 * This software was developed by the Computer Systems Engineering group 42 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 43 * contributed to Berkeley. 44 * 45 * All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Lawrence Berkeley Laboratories. 49 * 50 * Redistribution and use in source and binary forms, with or without 51 * modification, are permitted provided that the following conditions 52 * are met: 53 * 1. Redistributions of source code must retain the above copyright 54 * notice, this list of conditions and the following disclaimer. 55 * 2. Redistributions in binary form must reproduce the above copyright 56 * notice, this list of conditions and the following disclaimer in the 57 * documentation and/or other materials provided with the distribution. 58 * 3. Neither the name of the University nor the names of its contributors 59 * may be used to endorse or promote products derived from this software 60 * without specific prior written permission. 61 * 62 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 63 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 64 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 65 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 66 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 67 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 68 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 69 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 70 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 71 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 72 * SUCH DAMAGE. 73 * 74 * from: Header: subr_autoconf.c,v 1.12 93/02/01 19:31:48 torek Exp (LBL) 75 * 76 * @(#)subr_autoconf.c 8.3 (Berkeley) 5/17/94 77 */ 78 79 #include <sys/cdefs.h> 80 __KERNEL_RCSID(0, "$NetBSD: subr_evcnt.c,v 1.16 2021/04/15 00:37:31 rin Exp $"); 81 82 #include <sys/param.h> 83 #include <sys/evcnt.h> 84 #include <sys/kmem.h> 85 #include <sys/mutex.h> 86 #include <sys/sysctl.h> 87 #include <sys/systm.h> 88 89 /* 90 * Everything related to __HAVE_LEGACY_INTRCNT can disappear once 91 * no more ports are using old-style intrcnt/intrnames interrupt 92 * accounting. The follow files have __HAVE_LEGACY_INTRCNT code: 93 * 94 * sys/kern/init_main.c 95 * sys/kern/subr_evcnt.c 96 * sys/sys/evcnt.h 97 * sys/arch/<port>/include/types.h 98 */ 99 #ifdef _RUMPKERNEL 100 /* RUMP doesn't need/want to know about intrcnts */ 101 #undef __HAVE_LEGACY_INTRCNT 102 #endif 103 104 #ifdef __HAVE_LEGACY_INTRCNT 105 static void evcnt_update_intrcnt(void); 106 #endif 107 108 /* list of all events */ 109 struct evcntlist allevents = TAILQ_HEAD_INITIALIZER(allevents); 110 static kmutex_t evcnt_lock __cacheline_aligned; 111 static bool init_done; 112 static uint32_t evcnt_generation; 113 114 /* 115 * We need a dummy object to stuff into the evcnt link set to 116 * ensure that there always is at least one object in the set. 117 */ 118 static struct evcnt dummy_static_evcnt; 119 __link_set_add_bss(evcnts, dummy_static_evcnt); 120 121 /* 122 * Initialize event counters. This does the attach procedure for 123 * each of the static event counters in the "evcnts" link set. 124 */ 125 void 126 evcnt_init(void) 127 { 128 __link_set_decl(evcnts, struct evcnt); 129 struct evcnt * const *evp; 130 131 KASSERT(!init_done); 132 133 mutex_init(&evcnt_lock, MUTEX_DEFAULT, IPL_NONE); 134 135 init_done = true; 136 137 __link_set_foreach(evp, evcnts) { 138 if (*evp == &dummy_static_evcnt) 139 continue; 140 evcnt_attach_static(*evp); 141 } 142 } 143 144 /* 145 * Attach a statically-initialized event. The type and string pointers 146 * are already set up. 147 */ 148 void 149 evcnt_attach_static(struct evcnt *ev) 150 { 151 int len; 152 153 KASSERTMSG(init_done, 154 "%s: evcnt non initialized: group=<%s> name=<%s>", 155 __func__, ev->ev_group, ev->ev_name); 156 157 len = strlen(ev->ev_group); 158 #ifdef DIAGNOSTIC 159 if (len == 0 || len >= EVCNT_STRING_MAX) /* ..._MAX includes NUL */ 160 panic("evcnt_attach_static: group length (%s)", ev->ev_group); 161 #endif 162 ev->ev_grouplen = len; 163 164 len = strlen(ev->ev_name); 165 #ifdef DIAGNOSTIC 166 if (len == 0 || len >= EVCNT_STRING_MAX) /* ..._MAX includes NUL */ 167 panic("evcnt_attach_static: name length (%s)", ev->ev_name); 168 #endif 169 ev->ev_namelen = len; 170 171 mutex_enter(&evcnt_lock); 172 TAILQ_INSERT_TAIL(&allevents, ev, ev_list); 173 mutex_exit(&evcnt_lock); 174 } 175 176 /* 177 * Attach a dynamically-initialized event. Zero it, set up the type 178 * and string pointers and then act like it was statically initialized. 179 */ 180 void 181 evcnt_attach_dynamic_nozero(struct evcnt *ev, int type, 182 const struct evcnt *parent, const char *group, const char *name) 183 { 184 185 ev->ev_type = type; 186 ev->ev_parent = parent; 187 ev->ev_group = group; 188 ev->ev_name = name; 189 evcnt_attach_static(ev); 190 } 191 /* 192 * Attach a dynamically-initialized event. Zero it, set up the type 193 * and string pointers and then act like it was statically initialized. 194 */ 195 void 196 evcnt_attach_dynamic(struct evcnt *ev, int type, const struct evcnt *parent, 197 const char *group, const char *name) 198 { 199 200 memset(ev, 0, sizeof *ev); 201 evcnt_attach_dynamic_nozero(ev, type, parent, group, name); 202 } 203 204 /* 205 * Detach an event. 206 */ 207 void 208 evcnt_detach(struct evcnt *ev) 209 { 210 211 mutex_enter(&evcnt_lock); 212 TAILQ_REMOVE(&allevents, ev, ev_list); 213 evcnt_generation++; 214 mutex_exit(&evcnt_lock); 215 } 216 217 struct xevcnt_sysctl { 218 struct evcnt_sysctl evs; 219 char ev_strings[2*EVCNT_STRING_MAX]; 220 }; 221 222 static size_t 223 sysctl_fillevcnt(const struct evcnt *ev, struct xevcnt_sysctl *xevs, 224 size_t *copylenp) 225 { 226 const bool allowaddr = get_expose_address(curproc); 227 const size_t copylen = offsetof(struct evcnt_sysctl, ev_strings) 228 + ev->ev_grouplen + 1 + ev->ev_namelen + 1; 229 const size_t len = roundup2(copylen, sizeof(uint64_t)); 230 231 if (xevs != NULL) { 232 xevs->evs.ev_count = ev->ev_count; 233 COND_SET_VALUE(xevs->evs.ev_addr, PTRTOUINT64(ev), allowaddr); 234 COND_SET_VALUE(xevs->evs.ev_parent, PTRTOUINT64(ev->ev_parent), 235 allowaddr); 236 xevs->evs.ev_type = ev->ev_type; 237 xevs->evs.ev_grouplen = ev->ev_grouplen; 238 xevs->evs.ev_namelen = ev->ev_namelen; 239 xevs->evs.ev_len = len / sizeof(uint64_t); 240 strcpy(xevs->evs.ev_strings, ev->ev_group); 241 strcpy(xevs->evs.ev_strings + ev->ev_grouplen + 1, ev->ev_name); 242 } 243 244 *copylenp = copylen; 245 return len; 246 } 247 248 static int 249 sysctl_doevcnt(SYSCTLFN_ARGS) 250 { 251 struct xevcnt_sysctl *xevs0 = NULL, *xevs; 252 const struct evcnt *ev; 253 int error; 254 int retries; 255 size_t needed, len; 256 char *dp; 257 258 if (namelen == 1 && name[0] == CTL_QUERY) 259 return (sysctl_query(SYSCTLFN_CALL(rnode))); 260 261 if (namelen != 2) 262 return (EINVAL); 263 264 /* 265 * We can filter on the type of evcnt. 266 */ 267 const int filter = name[0]; 268 if (filter != EVCNT_TYPE_ANY 269 && filter != EVCNT_TYPE_MISC 270 && filter != EVCNT_TYPE_INTR 271 && filter != EVCNT_TYPE_TRAP) 272 return (EINVAL); 273 274 const u_int count = name[1]; 275 if (count != KERN_EVCNT_COUNT_ANY 276 && count != KERN_EVCNT_COUNT_NONZERO) 277 return (EINVAL); 278 279 sysctl_unlock(); 280 281 if (oldp != NULL && xevs0 == NULL) 282 xevs0 = kmem_zalloc(sizeof(*xevs0), KM_SLEEP); 283 284 retries = 100; 285 retry: 286 dp = oldp; 287 len = (oldp != NULL) ? *oldlenp : 0; 288 xevs = xevs0; 289 error = 0; 290 needed = 0; 291 292 mutex_enter(&evcnt_lock); 293 #ifdef __HAVE_LEGACY_INTRCNT 294 evcnt_update_intrcnt(); 295 #endif 296 TAILQ_FOREACH(ev, &allevents, ev_list) { 297 if (filter != EVCNT_TYPE_ANY && filter != ev->ev_type) 298 continue; 299 if (count == KERN_EVCNT_COUNT_NONZERO && ev->ev_count == 0) 300 continue; 301 302 /* 303 * Prepare to copy. If xevs is NULL, fillevcnt will just 304 * how big the item is. 305 */ 306 size_t copylen; 307 const size_t elem_size = sysctl_fillevcnt(ev, xevs, ©len); 308 needed += elem_size; 309 310 if (len < elem_size) { 311 xevs = NULL; 312 continue; 313 } 314 315 KASSERT(xevs != NULL); 316 KASSERT(xevs->evs.ev_grouplen != 0); 317 KASSERT(xevs->evs.ev_namelen != 0); 318 KASSERT(xevs->evs.ev_strings[0] != 0); 319 320 const uint32_t last_generation = evcnt_generation; 321 mutex_exit(&evcnt_lock); 322 323 /* 324 * Only copy the actual number of bytes, not the rounded 325 * number. If we did the latter we'd have to zero them 326 * first or we'd leak random kernel memory. 327 */ 328 error = copyout(xevs, dp, copylen); 329 330 mutex_enter(&evcnt_lock); 331 if (error) 332 break; 333 334 if (__predict_false(last_generation != evcnt_generation)) { 335 /* 336 * This sysctl node is only for statistics. 337 * Retry; if the queue keeps changing, then 338 * bail out. 339 */ 340 if (--retries == 0) { 341 error = EAGAIN; 342 break; 343 } 344 mutex_exit(&evcnt_lock); 345 goto retry; 346 } 347 348 /* 349 * Now we deal with the pointer/len since we aren't going to 350 * toss their values away. 351 */ 352 dp += elem_size; 353 len -= elem_size; 354 } 355 mutex_exit(&evcnt_lock); 356 357 if (xevs0 != NULL) 358 kmem_free(xevs0, sizeof(*xevs0)); 359 360 sysctl_relock(); 361 362 *oldlenp = needed; 363 if (oldp == NULL) 364 *oldlenp += 1024; 365 366 return (error); 367 } 368 369 370 371 SYSCTL_SETUP(sysctl_evcnt_setup, "sysctl kern.evcnt subtree setup") 372 { 373 374 sysctl_createv(clog, 0, NULL, NULL, 375 CTLFLAG_PERMANENT, 376 CTLTYPE_STRUCT, "evcnt", 377 SYSCTL_DESCR("Kernel evcnt information"), 378 sysctl_doevcnt, 0, NULL, 0, 379 CTL_KERN, KERN_EVCNT, CTL_EOL); 380 } 381 382 #ifdef __HAVE_LEGACY_INTRCNT 383 extern u_int intrcnt[], eintrcnt[]; 384 extern char intrnames[]; 385 static size_t nintr; 386 struct evcnt *intr_evcnts; 387 /* 388 * Remove the following when the last intrcnt/intrnames user is cleaned up. 389 */ 390 void 391 evcnt_attach_legacy_intrcnt(void) 392 { 393 size_t i; 394 const char *cp; 395 396 nintr = ((intptr_t)eintrcnt - (intptr_t)intrcnt) / sizeof(intrcnt[0]); 397 intr_evcnts = kmem_alloc(sizeof(struct evcnt) * nintr, KM_SLEEP); 398 for (cp = intrnames, i = 0; i < nintr; i++) { 399 evcnt_attach_dynamic(&intr_evcnts[i], EVCNT_TYPE_INTR, 400 NULL, "cpu", cp); 401 cp += strlen(cp) + 1; 402 } 403 } 404 405 static void 406 evcnt_update_intrcnt(void) 407 { 408 size_t i; 409 410 KASSERT(nintr > 0); 411 KASSERT(intr_evcnts != NULL); 412 413 for (i = 0; i < nintr; i++) { 414 intr_evcnts[i].ev_count = intrcnt[i]; 415 } 416 } 417 #endif 418
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