1 /* $NetBSD: nfs_fha.c,v 1.2 2016/12/13 22:41:46 pgoyette Exp $ */ 2 /*- 3 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/ 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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 /* __FBSDID("FreeBSD: head/sys/nfs/nfs_fha.c 267479 2014-06-14 12:26:12Z mav "); */ 29 __RCSID("$NetBSD: nfs_fha.c,v 1.2 2016/12/13 22:41:46 pgoyette Exp $"); 30 31 #include <sys/param.h> 32 #include <sys/systm.h> 33 #include <sys/sysproto.h> 34 #include <sys/kernel.h> 35 #include <sys/sysctl.h> 36 #include <sys/vnode.h> 37 #include <sys/malloc.h> 38 #include <sys/mount.h> 39 #include <sys/mbuf.h> 40 #include <sys/sbuf.h> 41 42 #include <rpc/rpc.h> 43 #include <fs/nfs/common/nfs_fha.h> 44 45 static MALLOC_DEFINE(M_NFS_FHA, "NFS FHA", "NFS FHA"); 46 47 /* 48 * XXX need to commonize definitions between old and new NFS code. Define 49 * this here so we don't include one nfsproto.h over the other. 50 */ 51 #define NFS_PROG 100003 52 53 void 54 fha_init(struct fha_params *softc) 55 { 56 char tmpstr[128]; 57 int i; 58 59 for (i = 0; i < FHA_HASH_SIZE; i++) 60 mtx_init(&softc->fha_hash[i].mtx, "fhalock", NULL, MTX_DEF); 61 62 /* 63 * Set the default tuning parameters. 64 */ 65 softc->ctls.enable = FHA_DEF_ENABLE; 66 softc->ctls.bin_shift = FHA_DEF_BIN_SHIFT; 67 softc->ctls.max_nfsds_per_fh = FHA_DEF_MAX_NFSDS_PER_FH; 68 softc->ctls.max_reqs_per_nfsd = FHA_DEF_MAX_REQS_PER_NFSD; 69 70 /* 71 * Allow the user to override the defaults at boot time with 72 * tunables. 73 */ 74 snprintf(tmpstr, sizeof(tmpstr), "vfs.%s.fha.enable", 75 softc->server_name); 76 TUNABLE_INT_FETCH(tmpstr, &softc->ctls.enable); 77 snprintf(tmpstr, sizeof(tmpstr), "vfs.%s.fha.bin_shift", 78 softc->server_name); 79 TUNABLE_INT_FETCH(tmpstr, &softc->ctls.bin_shift); 80 snprintf(tmpstr, sizeof(tmpstr), "vfs.%s.fha.max_nfsds_per_fh", 81 softc->server_name); 82 TUNABLE_INT_FETCH(tmpstr, &softc->ctls.max_nfsds_per_fh); 83 snprintf(tmpstr, sizeof(tmpstr), "vfs.%s.fha.max_reqs_per_nfsd", 84 softc->server_name); 85 TUNABLE_INT_FETCH(tmpstr, &softc->ctls.max_reqs_per_nfsd); 86 87 /* 88 * Add sysctls so the user can change the tuning parameters at 89 * runtime. 90 */ 91 SYSCTL_ADD_UINT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), 92 OID_AUTO, "enable", CTLFLAG_RW, 93 &softc->ctls.enable, 0, "Enable NFS File Handle Affinity (FHA)"); 94 95 SYSCTL_ADD_UINT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), 96 OID_AUTO, "bin_shift", CTLFLAG_RW, 97 &softc->ctls.bin_shift, 0, "For FHA reads, no two requests will " 98 "contend if they're 2^(bin_shift) bytes apart"); 99 100 SYSCTL_ADD_UINT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), 101 OID_AUTO, "max_nfsds_per_fh", CTLFLAG_RW, 102 &softc->ctls.max_nfsds_per_fh, 0, "Maximum nfsd threads that " 103 "should be working on requests for the same file handle"); 104 105 SYSCTL_ADD_UINT(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), 106 OID_AUTO, "max_reqs_per_nfsd", CTLFLAG_RW, 107 &softc->ctls.max_reqs_per_nfsd, 0, "Maximum requests that " 108 "single nfsd thread should be working on at any time"); 109 110 SYSCTL_ADD_OID(&softc->sysctl_ctx, SYSCTL_CHILDREN(softc->sysctl_tree), 111 OID_AUTO, "fhe_stats", CTLTYPE_STRING | CTLFLAG_RD, 0, 0, 112 softc->callbacks.fhe_stats_sysctl, "A", ""); 113 114 } 115 116 void 117 fha_uninit(struct fha_params *softc) 118 { 119 int i; 120 121 sysctl_ctx_free(&softc->sysctl_ctx); 122 for (i = 0; i < FHA_HASH_SIZE; i++) 123 mtx_destroy(&softc->fha_hash[i].mtx); 124 } 125 126 /* 127 * This just specifies that offsets should obey affinity when within 128 * the same 1Mbyte (1<<20) chunk for the file (reads only for now). 129 */ 130 static void 131 fha_extract_info(struct svc_req *req, struct fha_info *i, 132 struct fha_callbacks *cb) 133 { 134 struct mbuf *md; 135 caddr_t dpos; 136 static u_int64_t random_fh = 0; 137 int error; 138 int v3 = (req->rq_vers == 3); 139 rpcproc_t procnum; 140 141 /* 142 * We start off with a random fh. If we get a reasonable 143 * procnum, we set the fh. If there's a concept of offset 144 * that we're interested in, we set that. 145 */ 146 i->fh = ++random_fh; 147 i->offset = 0; 148 i->locktype = LK_EXCLUSIVE; 149 150 /* 151 * Extract the procnum and convert to v3 form if necessary, 152 * taking care to deal with out-of-range procnums. Caller will 153 * ensure that rq_vers is either 2 or 3. 154 */ 155 procnum = req->rq_proc; 156 if (!v3) { 157 rpcproc_t tmp_procnum; 158 159 tmp_procnum = cb->get_procnum(procnum); 160 if (tmp_procnum == -1) 161 goto out; 162 procnum = tmp_procnum; 163 } 164 165 /* 166 * We do affinity for most. However, we divide a realm of affinity 167 * by file offset so as to allow for concurrent random access. We 168 * only do this for reads today, but this may change when IFS supports 169 * efficient concurrent writes. 170 */ 171 if (cb->no_offset(procnum)) 172 goto out; 173 174 error = cb->realign(&req->rq_args, M_NOWAIT); 175 if (error) 176 goto out; 177 md = req->rq_args; 178 dpos = mtod(md, caddr_t); 179 180 /* Grab the filehandle. */ 181 error = cb->get_fh(&i->fh, v3, &md, &dpos); 182 if (error) 183 goto out; 184 185 /* Content ourselves with zero offset for all but reads. */ 186 if (cb->is_read(procnum) || cb->is_write(procnum)) 187 cb->get_offset(&md, &dpos, v3, i); 188 189 out: 190 cb->set_locktype(procnum, i); 191 } 192 193 static struct fha_hash_entry * 194 fha_hash_entry_new(u_int64_t fh) 195 { 196 struct fha_hash_entry *e; 197 198 e = malloc(sizeof(*e), M_NFS_FHA, M_WAITOK); 199 e->fh = fh; 200 e->num_rw = 0; 201 e->num_exclusive = 0; 202 e->num_threads = 0; 203 LIST_INIT(&e->threads); 204 205 return (e); 206 } 207 208 static void 209 fha_hash_entry_destroy(struct fha_hash_entry *e) 210 { 211 212 mtx_assert(e->mtx, MA_OWNED); 213 KASSERT(e->num_rw == 0, 214 ("%d reqs on destroyed fhe %p", e->num_rw, e)); 215 KASSERT(e->num_exclusive == 0, 216 ("%d exclusive reqs on destroyed fhe %p", e->num_exclusive, e)); 217 KASSERT(e->num_threads == 0, 218 ("%d threads on destroyed fhe %p", e->num_threads, e)); 219 free(e, M_NFS_FHA); 220 } 221 222 static void 223 fha_hash_entry_remove(struct fha_hash_entry *e) 224 { 225 226 mtx_assert(e->mtx, MA_OWNED); 227 LIST_REMOVE(e, link); 228 fha_hash_entry_destroy(e); 229 } 230 231 static struct fha_hash_entry * 232 fha_hash_entry_lookup(struct fha_params *softc, u_int64_t fh) 233 { 234 SVCPOOL *pool; 235 struct fha_hash_slot *fhs; 236 struct fha_hash_entry *fhe, *new_fhe; 237 238 pool = *softc->pool; 239 fhs = &softc->fha_hash[fh % FHA_HASH_SIZE]; 240 new_fhe = fha_hash_entry_new(fh); 241 new_fhe->mtx = &fhs->mtx; 242 mtx_lock(&fhs->mtx); 243 LIST_FOREACH(fhe, &fhs->list, link) 244 if (fhe->fh == fh) 245 break; 246 if (!fhe) { 247 fhe = new_fhe; 248 LIST_INSERT_HEAD(&fhs->list, fhe, link); 249 } else 250 fha_hash_entry_destroy(new_fhe); 251 return (fhe); 252 } 253 254 static void 255 fha_hash_entry_add_thread(struct fha_hash_entry *fhe, SVCTHREAD *thread) 256 { 257 258 mtx_assert(fhe->mtx, MA_OWNED); 259 thread->st_p2 = 0; 260 LIST_INSERT_HEAD(&fhe->threads, thread, st_alink); 261 fhe->num_threads++; 262 } 263 264 static void 265 fha_hash_entry_remove_thread(struct fha_hash_entry *fhe, SVCTHREAD *thread) 266 { 267 268 mtx_assert(fhe->mtx, MA_OWNED); 269 KASSERT(thread->st_p2 == 0, 270 ("%d reqs on removed thread %p", thread->st_p2, thread)); 271 LIST_REMOVE(thread, st_alink); 272 fhe->num_threads--; 273 } 274 275 /* 276 * Account for an ongoing operation associated with this file. 277 */ 278 static void 279 fha_hash_entry_add_op(struct fha_hash_entry *fhe, int locktype, int count) 280 { 281 282 mtx_assert(fhe->mtx, MA_OWNED); 283 if (LK_EXCLUSIVE == locktype) 284 fhe->num_exclusive += count; 285 else 286 fhe->num_rw += count; 287 } 288 289 /* 290 * Get the service thread currently associated with the fhe that is 291 * appropriate to handle this operation. 292 */ 293 static SVCTHREAD * 294 fha_hash_entry_choose_thread(struct fha_params *softc, 295 struct fha_hash_entry *fhe, struct fha_info *i, SVCTHREAD *this_thread) 296 { 297 SVCTHREAD *thread, *min_thread = NULL; 298 SVCPOOL *pool; 299 int req_count, min_count = 0; 300 off_t offset1, offset2; 301 302 pool = *softc->pool; 303 304 LIST_FOREACH(thread, &fhe->threads, st_alink) { 305 req_count = thread->st_p2; 306 307 /* If there are any writes in progress, use the first thread. */ 308 if (fhe->num_exclusive) { 309 #if 0 310 ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO, 311 "fha: %p(%d)w", thread, req_count); 312 #endif 313 return (thread); 314 } 315 316 /* 317 * Check for read locality, making sure that we won't 318 * exceed our per-thread load limit in the process. 319 */ 320 offset1 = i->offset; 321 offset2 = thread->st_p3; 322 323 if (((offset1 >= offset2) 324 && ((offset1 - offset2) < (1 << softc->ctls.bin_shift))) 325 || ((offset2 > offset1) 326 && ((offset2 - offset1) < (1 << softc->ctls.bin_shift)))) { 327 if ((softc->ctls.max_reqs_per_nfsd == 0) || 328 (req_count < softc->ctls.max_reqs_per_nfsd)) { 329 #if 0 330 ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO, 331 "fha: %p(%d)r", thread, req_count); 332 #endif 333 return (thread); 334 } 335 } 336 337 /* 338 * We don't have a locality match, so skip this thread, 339 * but keep track of the most attractive thread in case 340 * we need to come back to it later. 341 */ 342 #if 0 343 ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO, 344 "fha: %p(%d)s off1 %llu off2 %llu", thread, 345 req_count, offset1, offset2); 346 #endif 347 if ((min_thread == NULL) || (req_count < min_count)) { 348 min_count = req_count; 349 min_thread = thread; 350 } 351 } 352 353 /* 354 * We didn't find a good match yet. See if we can add 355 * a new thread to this file handle entry's thread list. 356 */ 357 if ((softc->ctls.max_nfsds_per_fh == 0) || 358 (fhe->num_threads < softc->ctls.max_nfsds_per_fh)) { 359 thread = this_thread; 360 #if 0 361 ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO, 362 "fha: %p(%d)t", thread, thread->st_p2); 363 #endif 364 fha_hash_entry_add_thread(fhe, thread); 365 } else { 366 /* 367 * We don't want to use any more threads for this file, so 368 * go back to the most attractive nfsd we're already using. 369 */ 370 thread = min_thread; 371 } 372 373 return (thread); 374 } 375 376 /* 377 * After getting a request, try to assign it to some thread. Usually we 378 * handle it ourselves. 379 */ 380 SVCTHREAD * 381 fha_assign(SVCTHREAD *this_thread, struct svc_req *req, 382 struct fha_params *softc) 383 { 384 SVCTHREAD *thread; 385 struct fha_info i; 386 struct fha_hash_entry *fhe; 387 struct fha_callbacks *cb; 388 389 cb = &softc->callbacks; 390 391 /* Check to see whether we're enabled. */ 392 if (softc->ctls.enable == 0) 393 goto thist; 394 395 /* 396 * Only do placement if this is an NFS request. 397 */ 398 if (req->rq_prog != NFS_PROG) 399 goto thist; 400 401 if (req->rq_vers != 2 && req->rq_vers != 3) 402 goto thist; 403 404 fha_extract_info(req, &i, cb); 405 406 /* 407 * We save the offset associated with this request for later 408 * nfsd matching. 409 */ 410 fhe = fha_hash_entry_lookup(softc, i.fh); 411 req->rq_p1 = fhe; 412 req->rq_p2 = i.locktype; 413 req->rq_p3 = i.offset; 414 415 /* 416 * Choose a thread, taking into consideration locality, thread load, 417 * and the number of threads already working on this file. 418 */ 419 thread = fha_hash_entry_choose_thread(softc, fhe, &i, this_thread); 420 KASSERT(thread, ("fha_assign: NULL thread!")); 421 fha_hash_entry_add_op(fhe, i.locktype, 1); 422 thread->st_p2++; 423 thread->st_p3 = i.offset; 424 425 /* 426 * Grab the pool lock here to not let chosen thread go away before 427 * the new request inserted to its queue while we drop fhe lock. 428 */ 429 mtx_lock(&thread->st_lock); 430 mtx_unlock(fhe->mtx); 431 432 return (thread); 433 thist: 434 req->rq_p1 = NULL; 435 mtx_lock(&this_thread->st_lock); 436 return (this_thread); 437 } 438 439 /* 440 * Called when we're done with an operation. The request has already 441 * been de-queued. 442 */ 443 void 444 fha_nd_complete(SVCTHREAD *thread, struct svc_req *req) 445 { 446 struct fha_hash_entry *fhe = req->rq_p1; 447 struct mtx *mtx; 448 449 /* 450 * This may be called for reqs that didn't go through 451 * fha_assign (e.g. extra NULL ops used for RPCSEC_GSS. 452 */ 453 if (!fhe) 454 return; 455 456 mtx = fhe->mtx; 457 mtx_lock(mtx); 458 fha_hash_entry_add_op(fhe, req->rq_p2, -1); 459 thread->st_p2--; 460 KASSERT(thread->st_p2 >= 0, ("Negative request count %d on %p", 461 thread->st_p2, thread)); 462 if (thread->st_p2 == 0) { 463 fha_hash_entry_remove_thread(fhe, thread); 464 if (0 == fhe->num_rw + fhe->num_exclusive) 465 fha_hash_entry_remove(fhe); 466 } 467 mtx_unlock(mtx); 468 } 469 470 int 471 fhe_stats_sysctl(SYSCTL_HANDLER_ARGS, struct fha_params *softc) 472 { 473 int error, i; 474 struct sbuf sb; 475 struct fha_hash_entry *fhe; 476 bool_t first, hfirst; 477 SVCTHREAD *thread; 478 SVCPOOL *pool; 479 480 sbuf_new(&sb, NULL, 65536, SBUF_FIXEDLEN); 481 482 pool = NULL; 483 484 if (!*softc->pool) { 485 sbuf_printf(&sb, "NFSD not running\n"); 486 goto out; 487 } 488 pool = *softc->pool; 489 490 for (i = 0; i < FHA_HASH_SIZE; i++) 491 if (!LIST_EMPTY(&softc->fha_hash[i].list)) 492 break; 493 494 if (i == FHA_HASH_SIZE) { 495 sbuf_printf(&sb, "No file handle entries.\n"); 496 goto out; 497 } 498 499 hfirst = TRUE; 500 for (; i < FHA_HASH_SIZE; i++) { 501 mtx_lock(&softc->fha_hash[i].mtx); 502 if (LIST_EMPTY(&softc->fha_hash[i].list)) { 503 mtx_unlock(&softc->fha_hash[i].mtx); 504 continue; 505 } 506 sbuf_printf(&sb, "%shash %d: {\n", hfirst ? "" : ", ", i); 507 first = TRUE; 508 LIST_FOREACH(fhe, &softc->fha_hash[i].list, link) { 509 sbuf_printf(&sb, "%sfhe %p: {\n", first ? " " : ", ", fhe); 510 511 sbuf_printf(&sb, " fh: %ju\n", (uintmax_t) fhe->fh); 512 sbuf_printf(&sb, " num_rw/exclusive: %d/%d\n", 513 fhe->num_rw, fhe->num_exclusive); 514 sbuf_printf(&sb, " num_threads: %d\n", fhe->num_threads); 515 516 LIST_FOREACH(thread, &fhe->threads, st_alink) { 517 sbuf_printf(&sb, " thread %p offset %ju " 518 "reqs %d\n", thread, 519 thread->st_p3, thread->st_p2); 520 } 521 522 sbuf_printf(&sb, " }"); 523 first = FALSE; 524 } 525 sbuf_printf(&sb, "\n}"); 526 mtx_unlock(&softc->fha_hash[i].mtx); 527 hfirst = FALSE; 528 } 529 530 out: 531 sbuf_trim(&sb); 532 sbuf_finish(&sb); 533 error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req); 534 sbuf_delete(&sb); 535 return (error); 536 } 537
Indexes created Sat Sep 20 22:09:52 GMT 2025