lustre/lov/lov_qos.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * GPL HEADER START
   5  *
   6  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 only,
  10  * as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License version 2 for more details (a copy is included
  16  * in the LICENSE file that accompanied this code).
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * version 2 along with this program; If not, see
  20  * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf
  21  *
  22  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  23  * CA 95054 USA or visit www.sun.com if you need additional information or
  24  * have any questions.
  25  *
  26  * GPL HEADER END
  27  */
  28 /*
  29  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  30  * Use is subject to license terms.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  */
  36
  37 #ifndef EXPORT_SYMTAB
  38 # define EXPORT_SYMTAB
  39 #endif
  40 #define DEBUG_SUBSYSTEM S_LOV
  41
  42 #ifdef __KERNEL__
  43 #include <libcfs/libcfs.h>
  44 #else
  45 #include <liblustre.h>
  46 #endif
  47
  48 #include <obd_class.h>
  49 #include <obd_lov.h>
  50 #include <lustre/lustre_idl.h>
  51 #include "lov_internal.h"
  52
  53 /* #define QOS_DEBUG 1 */
  54 #define D_QOS D_OTHER
  55
  56 #define TGT_BAVAIL(i) (lov->lov_tgts[i]->ltd_exp->exp_obd->obd_osfs.os_bavail *\
  57                        lov->lov_tgts[i]->ltd_exp->exp_obd->obd_osfs.os_bsize)
  58
  59
  60 int qos_add_tgt(struct obd_device *obd, __u32 index)
  61 {
  62         struct lov_obd *lov = &obd->u.lov;
  63         struct lov_qos_oss *oss, *temposs;
  64         struct obd_export *exp = lov->lov_tgts[index]->ltd_exp;
  65         int rc = 0, found = 0;
  66         ENTRY;
  67
  68         /* We only need this QOS struct on MDT, not clients - but we may not
  69          * have registered the LOV's observer yet, so there's no way to know */
  70         if (!exp || !exp->exp_connection) {
  71                 CERROR("Missing connection\n");
  72                 RETURN(-ENOTCONN);
  73         }
  74
  75         cfs_down_write(&lov->lov_qos.lq_rw_sem);
  76         cfs_mutex_down(&lov->lov_lock);
  77         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
  78                 if (obd_uuid_equals(&oss->lqo_uuid,
  79                                     &exp->exp_connection->c_remote_uuid)) {
  80                         found++;
  81                         break;
  82                 }
  83         }
  84
  85         if (!found) {
  86                 OBD_ALLOC_PTR(oss);
  87                 if (!oss)
  88                         GOTO(out, rc = -ENOMEM);
  89                 memcpy(&oss->lqo_uuid,
  90                        &exp->exp_connection->c_remote_uuid,
  91                        sizeof(oss->lqo_uuid));
  92         } else {
  93                 /* Assume we have to move this one */
  94                 cfs_list_del(&oss->lqo_oss_list);
  95         }
  96
  97         oss->lqo_ost_count++;
  98         lov->lov_tgts[index]->ltd_qos.ltq_oss = oss;
  99
 100         /* Add sorted by # of OSTs.  Find the first entry that we're
 101            bigger than... */
 102         cfs_list_for_each_entry(temposs, &lov->lov_qos.lq_oss_list,
 103                                 lqo_oss_list) {
 104                 if (oss->lqo_ost_count > temposs->lqo_ost_count)
 105                         break;
 106         }
 107         /* ...and add before it.  If we're the first or smallest, temposs
 108            points to the list head, and we add to the end. */
 109         cfs_list_add_tail(&oss->lqo_oss_list, &temposs->lqo_oss_list);
 110
 111         lov->lov_qos.lq_dirty = 1;
 112         lov->lov_qos.lq_rr.lqr_dirty = 1;
 113
 114         CDEBUG(D_QOS, "add tgt %s to OSS %s (%d OSTs)\n",
 115                obd_uuid2str(&lov->lov_tgts[index]->ltd_uuid),
 116                obd_uuid2str(&oss->lqo_uuid),
 117                oss->lqo_ost_count);
 118
 119 out:
 120         cfs_mutex_up(&lov->lov_lock);
 121         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 122         RETURN(rc);
 123 }
 124
 125 int qos_del_tgt(struct obd_device *obd, struct lov_tgt_desc *tgt)
 126 {
 127         struct lov_obd *lov = &obd->u.lov;
 128         struct lov_qos_oss *oss;
 129         int rc = 0;
 130         ENTRY;
 131
 132         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 133
 134         oss = tgt->ltd_qos.ltq_oss;
 135         if (!oss)
 136                 GOTO(out, rc = -ENOENT);
 137
 138         oss->lqo_ost_count--;
 139         if (oss->lqo_ost_count == 0) {
 140                 CDEBUG(D_QOS, "removing OSS %s\n",
 141                        obd_uuid2str(&oss->lqo_uuid));
 142                 cfs_list_del(&oss->lqo_oss_list);
 143                 OBD_FREE_PTR(oss);
 144         }
 145
 146         lov->lov_qos.lq_dirty = 1;
 147         lov->lov_qos.lq_rr.lqr_dirty = 1;
 148 out:
 149         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 150         RETURN(rc);
 151 }
 152
 153 /* Recalculate per-object penalties for OSSs and OSTs,
 154    depends on size of each ost in an oss */
 155 static int qos_calc_ppo(struct obd_device *obd)
 156 {
 157         struct lov_obd *lov = &obd->u.lov;
 158         struct lov_qos_oss *oss;
 159         __u64 ba_max, ba_min, temp;
 160         __u32 num_active;
 161         int rc, i, prio_wide;
 162         time_t now, age;
 163         ENTRY;
 164
 165         if (!lov->lov_qos.lq_dirty)
 166                 GOTO(out, rc = 0);
 167
 168         num_active = lov->desc.ld_active_tgt_count - 1;
 169         if (num_active < 1)
 170                 GOTO(out, rc = -EAGAIN);
 171
 172         /* find bavail on each OSS */
 173         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 174                 oss->lqo_bavail = 0;
 175         }
 176         lov->lov_qos.lq_active_oss_count = 0;
 177
 178         /* How badly user wants to select osts "widely" (not recently chosen
 179            and not on recent oss's).  As opposed to "freely" (free space
 180            avail.) 0-256. */
 181         prio_wide = 256 - lov->lov_qos.lq_prio_free;
 182
 183         ba_min = (__u64)(-1);
 184         ba_max = 0;
 185         now = cfs_time_current_sec();
 186         /* Calculate OST penalty per object */
 187         /* (lov ref taken in alloc_qos) */
 188         for (i = 0; i < lov->desc.ld_tgt_count; i++) {
 189                 if (!lov->lov_tgts[i] || !lov->lov_tgts[i]->ltd_active)
 190                         continue;
 191                 temp = TGT_BAVAIL(i);
 192                 if (!temp)
 193                         continue;
 194                 ba_min = min(temp, ba_min);
 195                 ba_max = max(temp, ba_max);
 196
 197                 /* Count the number of usable OSS's */
 198                 if (lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_bavail == 0)
 199                         lov->lov_qos.lq_active_oss_count++;
 200                 lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_bavail += temp;
 201
 202                 /* per-OST penalty is prio * TGT_bavail / (num_ost - 1) / 2 */
 203                 temp >>= 1;
 204                 do_div(temp, num_active);
 205                 lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj =
 206                         (temp * prio_wide) >> 8;
 207
 208                 age = (now - lov->lov_tgts[i]->ltd_qos.ltq_used) >> 3;
 209                 if (lov->lov_qos.lq_reset || age > 32 * lov->desc.ld_qos_maxage)
 210                         lov->lov_tgts[i]->ltd_qos.ltq_penalty = 0;
 211                 else if (age > lov->desc.ld_qos_maxage)
 212                         /* Decay the penalty by half for every 8x the update
 213                          * interval that the device has been idle.  That gives
 214                          * lots of time for the statfs information to be
 215                          * updated (which the penalty is only a proxy for),
 216                          * and avoids penalizing OSS/OSTs under light load. */
 217                         lov->lov_tgts[i]->ltd_qos.ltq_penalty >>=
 218                                 (age / lov->desc.ld_qos_maxage);
 219         }
 220
 221         num_active = lov->lov_qos.lq_active_oss_count - 1;
 222         if (num_active < 1) {
 223                 /* If there's only 1 OSS, we can't penalize it, so instead
 224                    we have to double the OST penalty */
 225                 num_active = 1;
 226                 for (i = 0; i < lov->desc.ld_tgt_count; i++) {
 227                         if (lov->lov_tgts[i] == NULL)
 228                                 continue;
 229                         lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj <<= 1;
 230                 }
 231         }
 232
 233         /* Per-OSS penalty is prio * oss_avail / oss_osts / (num_oss - 1) / 2 */
 234         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 235                 temp = oss->lqo_bavail >> 1;
 236                 do_div(temp, oss->lqo_ost_count * num_active);
 237                 oss->lqo_penalty_per_obj = (temp * prio_wide) >> 8;
 238
 239                 age = (now - oss->lqo_used) >> 3;
 240                 if (lov->lov_qos.lq_reset || age > 32 * lov->desc.ld_qos_maxage)
 241                         oss->lqo_penalty = 0;
 242                 else if (age > lov->desc.ld_qos_maxage)
 243                         /* Decay the penalty by half for every 8x the update
 244                          * interval that the device has been idle.  That gives
 245                          * lots of time for the statfs information to be
 246                          * updated (which the penalty is only a proxy for),
 247                          * and avoids penalizing OSS/OSTs under light load. */
 248                         oss->lqo_penalty >>= (age / lov->desc.ld_qos_maxage);
 249         }
 250
 251         lov->lov_qos.lq_dirty = 0;
 252         lov->lov_qos.lq_reset = 0;
 253
 254         /* If each ost has almost same free space,
 255          * do rr allocation for better creation performance */
 256         lov->lov_qos.lq_same_space = 0;
 257         if ((ba_max * (256 - lov->lov_qos.lq_threshold_rr)) >> 8 < ba_min) {
 258                 lov->lov_qos.lq_same_space = 1;
 259                 /* Reset weights for the next time we enter qos mode */
 260                 lov->lov_qos.lq_reset = 1;
 261         }
 262         rc = 0;
 263
 264 out:
 265         if (!rc && lov->lov_qos.lq_same_space)
 266                 RETURN(-EAGAIN);
 267         RETURN(rc);
 268 }
 269
 270 static int qos_calc_weight(struct lov_obd *lov, int i)
 271 {
 272         __u64 temp, temp2;
 273
 274         /* Final ost weight = TGT_BAVAIL - ost_penalty - oss_penalty */
 275         temp = TGT_BAVAIL(i);
 276         temp2 = lov->lov_tgts[i]->ltd_qos.ltq_penalty +
 277                 lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty;
 278         if (temp < temp2)
 279                 lov->lov_tgts[i]->ltd_qos.ltq_weight = 0;
 280         else
 281                 lov->lov_tgts[i]->ltd_qos.ltq_weight = temp - temp2;
 282         return 0;
 283 }
 284
 285 /* We just used this index for a stripe; adjust everyone's weights */
 286 static int qos_used(struct lov_obd *lov, struct ost_pool *osts,
 287                     __u32 index, __u64 *total_wt)
 288 {
 289         struct lov_qos_oss *oss;
 290         int j;
 291         ENTRY;
 292
 293         /* Don't allocate from this stripe anymore, until the next alloc_qos */
 294         lov->lov_tgts[index]->ltd_qos.ltq_usable = 0;
 295
 296         oss = lov->lov_tgts[index]->ltd_qos.ltq_oss;
 297
 298         /* Decay old penalty by half (we're adding max penalty, and don't
 299            want it to run away.) */
 300         lov->lov_tgts[index]->ltd_qos.ltq_penalty >>= 1;
 301         oss->lqo_penalty >>= 1;
 302
 303         /* mark the OSS and OST as recently used */
 304         lov->lov_tgts[index]->ltd_qos.ltq_used =
 305                 oss->lqo_used = cfs_time_current_sec();
 306
 307         /* Set max penalties for this OST and OSS */
 308         lov->lov_tgts[index]->ltd_qos.ltq_penalty +=
 309                 lov->lov_tgts[index]->ltd_qos.ltq_penalty_per_obj *
 310                 lov->desc.ld_active_tgt_count;
 311         oss->lqo_penalty += oss->lqo_penalty_per_obj *
 312                 lov->lov_qos.lq_active_oss_count;
 313
 314         /* Decrease all OSS penalties */
 315         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 316                 if (oss->lqo_penalty < oss->lqo_penalty_per_obj)
 317                         oss->lqo_penalty = 0;
 318                 else
 319                         oss->lqo_penalty -= oss->lqo_penalty_per_obj;
 320         }
 321
 322         *total_wt = 0;
 323         /* Decrease all OST penalties */
 324         for (j = 0; j < osts->op_count; j++) {
 325                 int i;
 326
 327                 i = osts->op_array[j];
 328                 if (!lov->lov_tgts[i] || !lov->lov_tgts[i]->ltd_active)
 329                         continue;
 330                 if (lov->lov_tgts[i]->ltd_qos.ltq_penalty <
 331                     lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj)
 332                         lov->lov_tgts[i]->ltd_qos.ltq_penalty = 0;
 333                 else
 334                         lov->lov_tgts[i]->ltd_qos.ltq_penalty -=
 335                         lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj;
 336
 337                 qos_calc_weight(lov, i);
 338
 339                 /* Recalc the total weight of usable osts */
 340                 if (lov->lov_tgts[i]->ltd_qos.ltq_usable)
 341                         *total_wt += lov->lov_tgts[i]->ltd_qos.ltq_weight;
 342
 343 #ifdef QOS_DEBUG
 344                 CDEBUG(D_QOS, "recalc tgt %d usable=%d avail="LPU64
 345                        " ostppo="LPU64" ostp="LPU64" ossppo="LPU64
 346                        " ossp="LPU64" wt="LPU64"\n",
 347                        i, lov->lov_tgts[i]->ltd_qos.ltq_usable,
 348                        TGT_BAVAIL(i) >> 10,
 349                        lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj >> 10,
 350                        lov->lov_tgts[i]->ltd_qos.ltq_penalty >> 10,
 351                        lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty_per_obj>>10,
 352                        lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty >> 10,
 353                        lov->lov_tgts[i]->ltd_qos.ltq_weight >> 10);
 354 #endif
 355         }
 356
 357         RETURN(0);
 358 }
 359
 360 #define LOV_QOS_EMPTY ((__u32)-1)
 361 /* compute optimal round-robin order, based on OSTs per OSS */
 362 static int qos_calc_rr(struct lov_obd *lov, struct ost_pool *src_pool,
 363                        struct lov_qos_rr *lqr)
 364 {
 365         struct lov_qos_oss *oss;
 366         unsigned placed, real_count;
 367         int i, rc;
 368         ENTRY;
 369
 370         if (!lqr->lqr_dirty) {
 371                 LASSERT(lqr->lqr_pool.op_size);
 372                 RETURN(0);
 373         }
 374
 375         /* Do actual allocation. */
 376         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 377
 378         /*
 379          * Check again. While we were sleeping on @lq_rw_sem something could
 380          * change.
 381          */
 382         if (!lqr->lqr_dirty) {
 383                 LASSERT(lqr->lqr_pool.op_size);
 384                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
 385                 RETURN(0);
 386         }
 387
 388         real_count = src_pool->op_count;
 389
 390         /* Zero the pool array */
 391         /* alloc_rr is holding a read lock on the pool, so nobody is adding/
 392            deleting from the pool. The lq_rw_sem insures that nobody else
 393            is reading. */
 394         lqr->lqr_pool.op_count = real_count;
 395         rc = lov_ost_pool_extend(&lqr->lqr_pool, real_count);
 396         if (rc) {
 397                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
 398                 RETURN(rc);
 399         }
 400         for (i = 0; i < lqr->lqr_pool.op_count; i++)
 401                 lqr->lqr_pool.op_array[i] = LOV_QOS_EMPTY;
 402
 403         /* Place all the OSTs from 1 OSS at the same time. */
 404         placed = 0;
 405         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 406                 int j = 0;
 407                 for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 408                         if (lov->lov_tgts[src_pool->op_array[i]] &&
 409                             (lov->lov_tgts[src_pool->op_array[i]]->ltd_qos.ltq_oss == oss)) {
 410                               /* Evenly space these OSTs across arrayspace */
 411                               int next = j * lqr->lqr_pool.op_count / oss->lqo_ost_count;
 412                               while (lqr->lqr_pool.op_array[next] !=
 413                                      LOV_QOS_EMPTY)
 414                                         next = (next + 1) % lqr->lqr_pool.op_count;
 415                               lqr->lqr_pool.op_array[next] = src_pool->op_array[i];
 416                               j++;
 417                               placed++;
 418                         }
 419                 }
 420         }
 421
 422         lqr->lqr_dirty = 0;
 423         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 424
 425         if (placed != real_count) {
 426                 /* This should never happen */
 427                 LCONSOLE_ERROR_MSG(0x14e, "Failed to place all OSTs in the "
 428                                    "round-robin list (%d of %d).\n",
 429                                    placed, real_count);
 430                 for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 431                         LCONSOLE(D_WARNING, "rr #%d ost idx=%d\n", i,
 432                                  lqr->lqr_pool.op_array[i]);
 433                 }
 434                 lqr->lqr_dirty = 1;
 435                 RETURN(-EAGAIN);
 436         }
 437
 438 #ifdef QOS_DEBUG
 439         for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 440                 LCONSOLE(D_QOS, "rr #%d ost idx=%d\n", i,
 441                          lqr->lqr_pool.op_array[i]);
 442         }
 443 #endif
 444
 445         RETURN(0);
 446 }
 447
 448
 449 void qos_shrink_lsm(struct lov_request_set *set)
 450 {
 451         struct lov_stripe_md *lsm = set->set_oi->oi_md, *lsm_new;
 452         /* XXX LOV STACKING call into osc for sizes */
 453         unsigned oldsize, newsize;
 454
 455         if (set->set_oti && set->set_cookies && set->set_cookie_sent) {
 456                 struct llog_cookie *cookies;
 457                 oldsize = lsm->lsm_stripe_count * sizeof(*cookies);
 458                 newsize = set->set_count * sizeof(*cookies);
 459
 460                 cookies = set->set_cookies;
 461                 oti_alloc_cookies(set->set_oti, set->set_count);
 462                 if (set->set_oti->oti_logcookies) {
 463                         memcpy(set->set_oti->oti_logcookies, cookies, newsize);
 464                         OBD_FREE_LARGE(cookies, oldsize);
 465                         set->set_cookies = set->set_oti->oti_logcookies;
 466                 } else {
 467                         CWARN("'leaking' %d bytes\n", oldsize - newsize);
 468                 }
 469         }
 470
 471         CWARN("using fewer stripes for object "LPU64": old %u new %u\n",
 472               lsm->lsm_object_id, lsm->lsm_stripe_count, set->set_count);
 473         LASSERT(lsm->lsm_stripe_count >= set->set_count);
 474
 475         newsize = lov_stripe_md_size(set->set_count);
 476         OBD_ALLOC_LARGE(lsm_new, newsize);
 477         if (lsm_new != NULL) {
 478                 int i;
 479                 memcpy(lsm_new, lsm, sizeof(*lsm));
 480                 for (i = 0; i < lsm->lsm_stripe_count; i++) {
 481                         if (i < set->set_count) {
 482                                 lsm_new->lsm_oinfo[i] = lsm->lsm_oinfo[i];
 483                                 continue;
 484                         }
 485                         OBD_SLAB_FREE(lsm->lsm_oinfo[i], lov_oinfo_slab,
 486                                       sizeof(struct lov_oinfo));
 487                 }
 488                 lsm_new->lsm_stripe_count = set->set_count;
 489                 OBD_FREE_LARGE(lsm, sizeof(struct lov_stripe_md) +
 490                                lsm->lsm_stripe_count*sizeof(struct lov_oinfo*));
 491                 set->set_oi->oi_md = lsm_new;
 492         } else {
 493                 CWARN("'leaking' few bytes\n");
 494         }
 495 }
 496
 497 /**
 498  * Check whether we can create the object on the OST(refered by ost_idx)
 499  * \retval:
 500  *          0: create the object.
 501  *          other value: did not create the object.
 502  */
 503 static int lov_check_and_create_object(struct lov_obd *lov, int ost_idx,
 504                                        struct lov_stripe_md *lsm,
 505                                        struct lov_request *req,
 506                                        struct obd_trans_info *oti)
 507 {
 508         int stripe;
 509         int rc = -EIO;
 510         ENTRY;
 511
 512         CDEBUG(D_QOS, "Check and create on idx %d \n", ost_idx);
 513         if (!lov->lov_tgts[ost_idx] ||
 514             !lov->lov_tgts[ost_idx]->ltd_active)
 515                 RETURN(rc);
 516
 517         /* check if objects has been created on this ost */
 518         for (stripe = 0; stripe < lsm->lsm_stripe_count; stripe++) {
 519                 /* already have object at this stripe */
 520                 if (ost_idx == lsm->lsm_oinfo[stripe]->loi_ost_idx)
 521                         break;
 522         }
 523
 524         if (stripe >= lsm->lsm_stripe_count) {
 525                 req->rq_idx = ost_idx;
 526                 rc = obd_create(lov->lov_tgts[ost_idx]->ltd_exp,
 527                                 req->rq_oi.oi_oa, &req->rq_oi.oi_md,
 528                                 oti);
 529         }
 530         RETURN(rc);
 531 }
 532
 533 int qos_remedy_create(struct lov_request_set *set, struct lov_request *req)
 534 {
 535         struct lov_stripe_md *lsm = set->set_oi->oi_md;
 536         struct lov_obd *lov = &set->set_exp->exp_obd->u.lov;
 537         unsigned ost_idx, ost_count;
 538         struct pool_desc *pool;
 539         struct ost_pool *osts = NULL;
 540         int i, rc = -EIO;
 541         ENTRY;
 542
 543         /* First check whether we can create the objects on the pool */
 544         pool = lov_find_pool(lov, lsm->lsm_pool_name);
 545         if (pool != NULL) {
 546                 cfs_down_read(&pool_tgt_rw_sem(pool));
 547                 osts = &(pool->pool_obds);
 548                 ost_count = osts->op_count;
 549                 for (i = 0, ost_idx = osts->op_array[0]; i < ost_count;
 550                      i++, ost_idx = osts->op_array[i]) {
 551                         rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 552                                                          set->set_oti);
 553                         if (rc == 0)
 554                                 break;
 555                 }
 556                 cfs_up_read(&pool_tgt_rw_sem(pool));
 557                 lov_pool_putref(pool);
 558                 RETURN(rc);
 559         }
 560
 561         ost_count = lov->desc.ld_tgt_count;
 562         /* Then check whether we can create the objects on other OSTs */
 563         ost_idx = (req->rq_idx + lsm->lsm_stripe_count) % ost_count;
 564         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
 565                 rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 566                                                  set->set_oti);
 567
 568                 if (rc == 0)
 569                         break;
 570         }
 571
 572         RETURN(rc);
 573 }
 574
 575 static int min_stripe_count(int stripe_cnt, int flags)
 576 {
 577         return (flags & LOV_USES_DEFAULT_STRIPE ?
 578                 stripe_cnt - (stripe_cnt / 4) : stripe_cnt);
 579 }
 580
 581 #define LOV_CREATE_RESEED_MULT 30
 582 #define LOV_CREATE_RESEED_MIN  2000
 583 /* Allocate objects on osts with round-robin algorithm */
 584 static int alloc_rr(struct lov_obd *lov, int *idx_arr, int *stripe_cnt,
 585                     char *poolname, int flags)
 586 {
 587         unsigned array_idx;
 588         int i, rc, *idx_pos;
 589         __u32 ost_idx;
 590         int ost_start_idx_temp;
 591         int speed = 0;
 592         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 593         struct pool_desc *pool;
 594         struct ost_pool *osts;
 595         struct lov_qos_rr *lqr;
 596         ENTRY;
 597
 598         pool = lov_find_pool(lov, poolname);
 599         if (pool == NULL) {
 600                 osts = &(lov->lov_packed);
 601                 lqr = &(lov->lov_qos.lq_rr);
 602         } else {
 603                 cfs_down_read(&pool_tgt_rw_sem(pool));
 604                 osts = &(pool->pool_obds);
 605                 lqr = &(pool->pool_rr);
 606         }
 607
 608         rc = qos_calc_rr(lov, osts, lqr);
 609         if (rc)
 610                 GOTO(out, rc);
 611
 612         if (--lqr->lqr_start_count <= 0) {
 613                 lqr->lqr_start_idx = cfs_rand() % osts->op_count;
 614                 lqr->lqr_start_count =
 615                         (LOV_CREATE_RESEED_MIN / max(osts->op_count, 1U) +
 616                          LOV_CREATE_RESEED_MULT) * max(osts->op_count, 1U);
 617         } else if (stripe_cnt_min >= osts->op_count ||
 618                    lqr->lqr_start_idx > osts->op_count) {
 619                 /* If we have allocated from all of the OSTs, slowly
 620                  * precess the next start if the OST/stripe count isn't
 621                  * already doing this for us. */
 622                 lqr->lqr_start_idx %= osts->op_count;
 623                 if (*stripe_cnt > 1 && (osts->op_count % (*stripe_cnt)) != 1)
 624                         ++lqr->lqr_offset_idx;
 625         }
 626         cfs_down_read(&lov->lov_qos.lq_rw_sem);
 627         ost_start_idx_temp = lqr->lqr_start_idx;
 628
 629 repeat_find:
 630         array_idx = (lqr->lqr_start_idx + lqr->lqr_offset_idx) % osts->op_count;
 631         idx_pos = idx_arr;
 632 #ifdef QOS_DEBUG
 633         CDEBUG(D_QOS, "pool '%s' want %d startidx %d startcnt %d offset %d "
 634                "active %d count %d arrayidx %d\n", poolname,
 635                *stripe_cnt, lqr->lqr_start_idx, lqr->lqr_start_count,
 636                lqr->lqr_offset_idx, osts->op_count, osts->op_count, array_idx);
 637 #endif
 638
 639         for (i = 0; i < osts->op_count;
 640                     i++, array_idx=(array_idx + 1) % osts->op_count) {
 641                 ++lqr->lqr_start_idx;
 642                 ost_idx = lqr->lqr_pool.op_array[array_idx];
 643 #ifdef QOS_DEBUG
 644                 CDEBUG(D_QOS, "#%d strt %d act %d strp %d ary %d idx %d\n",
 645                        i, lqr->lqr_start_idx,
 646                        ((ost_idx != LOV_QOS_EMPTY) && lov->lov_tgts[ost_idx]) ?
 647                        lov->lov_tgts[ost_idx]->ltd_active : 0,
 648                        idx_pos - idx_arr, array_idx, ost_idx);
 649 #endif
 650                 if ((ost_idx == LOV_QOS_EMPTY) || !lov->lov_tgts[ost_idx] ||
 651                     !lov->lov_tgts[ost_idx]->ltd_active)
 652                         continue;
 653
 654                 /* Fail Check before osc_precreate() is called
 655                    so we can only 'fail' single OSC. */
 656                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 657                         continue;
 658
 659                 /* Drop slow OSCs if we can */
 660                 if (obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed)
 661                         continue;
 662
 663                 *idx_pos = ost_idx;
 664                 idx_pos++;
 665                 /* We have enough stripes */
 666                 if (idx_pos - idx_arr == *stripe_cnt)
 667                         break;
 668         }
 669         if ((speed < 2) && (idx_pos - idx_arr < stripe_cnt_min)) {
 670                 /* Try again, allowing slower OSCs */
 671                 speed++;
 672                 lqr->lqr_start_idx = ost_start_idx_temp;
 673                 goto repeat_find;
 674         }
 675
 676         cfs_up_read(&lov->lov_qos.lq_rw_sem);
 677
 678         *stripe_cnt = idx_pos - idx_arr;
 679 out:
 680         if (pool != NULL) {
 681                 cfs_up_read(&pool_tgt_rw_sem(pool));
 682                 /* put back ref got by lov_find_pool() */
 683                 lov_pool_putref(pool);
 684         }
 685
 686         RETURN(rc);
 687 }
 688
 689 /* alloc objects on osts with specific stripe offset */
 690 static int alloc_specific(struct lov_obd *lov, struct lov_stripe_md *lsm,
 691                           int *idx_arr)
 692 {
 693         unsigned ost_idx, array_idx, ost_count;
 694         int i, rc, *idx_pos;
 695         int speed = 0;
 696         struct pool_desc *pool;
 697         struct ost_pool *osts;
 698         ENTRY;
 699
 700         pool = lov_find_pool(lov, lsm->lsm_pool_name);
 701         if (pool == NULL) {
 702                 osts = &(lov->lov_packed);
 703         } else {
 704                 cfs_down_read(&pool_tgt_rw_sem(pool));
 705                 osts = &(pool->pool_obds);
 706         }
 707
 708         ost_count = osts->op_count;
 709
 710 repeat_find:
 711         /* search loi_ost_idx in ost array */
 712         array_idx = 0;
 713         for (i = 0; i < ost_count; i++) {
 714                 if (osts->op_array[i] == lsm->lsm_oinfo[0]->loi_ost_idx) {
 715                         array_idx = i;
 716                         break;
 717                 }
 718         }
 719         if (i == ost_count) {
 720                 CERROR("Start index %d not found in pool '%s'\n",
 721                        lsm->lsm_oinfo[0]->loi_ost_idx, lsm->lsm_pool_name);
 722                 GOTO(out, rc = -EINVAL);
 723         }
 724
 725         idx_pos = idx_arr;
 726         for (i = 0; i < ost_count;
 727              i++, array_idx = (array_idx + 1) % ost_count) {
 728                 ost_idx = osts->op_array[array_idx];
 729
 730                 if (!lov->lov_tgts[ost_idx] ||
 731                     !lov->lov_tgts[ost_idx]->ltd_active) {
 732                         continue;
 733                 }
 734
 735                 /* Fail Check before osc_precreate() is called
 736                    so we can only 'fail' single OSC. */
 737                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 738                         continue;
 739
 740                 /* Drop slow OSCs if we can, but not for requested start idx.
 741                  *
 742                  * This means "if OSC is slow and it is not the requested
 743                  * start OST, then it can be skipped, otherwise skip it only
 744                  * if it is inactive/recovering/out-of-space." */
 745                 if ((obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed) &&
 746                     (i != 0 || speed >= 2))
 747                         continue;
 748
 749                 *idx_pos = ost_idx;
 750                 idx_pos++;
 751                 /* We have enough stripes */
 752                 if (idx_pos - idx_arr == lsm->lsm_stripe_count)
 753                         GOTO(out, rc = 0);
 754         }
 755         if (speed < 2) {
 756                 /* Try again, allowing slower OSCs */
 757                 speed++;
 758                 goto repeat_find;
 759         }
 760
 761         /* If we were passed specific striping params, then a failure to
 762          * meet those requirements is an error, since we can't reallocate
 763          * that memory (it might be part of a larger array or something).
 764          *
 765          * We can only get here if lsm_stripe_count was originally > 1.
 766          */
 767         CERROR("can't lstripe objid "LPX64": have %d want %u\n",
 768                lsm->lsm_object_id, (int)(idx_pos - idx_arr),
 769                lsm->lsm_stripe_count);
 770         rc = -EFBIG;
 771 out:
 772         if (pool != NULL) {
 773                 cfs_up_read(&pool_tgt_rw_sem(pool));
 774                 /* put back ref got by lov_find_pool() */
 775                 lov_pool_putref(pool);
 776         }
 777
 778         RETURN(rc);
 779 }
 780
 781 /* Alloc objects on osts with optimization based on:
 782    - free space
 783    - network resources (shared OSS's)
 784 */
 785 static int alloc_qos(struct obd_export *exp, int *idx_arr, int *stripe_cnt,
 786                      char *poolname, int flags)
 787 {
 788         struct lov_obd *lov = &exp->exp_obd->u.lov;
 789         __u64 total_weight = 0;
 790         int nfound, good_osts, i, rc = 0;
 791         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 792         struct pool_desc *pool;
 793         struct ost_pool *osts;
 794         struct lov_qos_rr *lqr;
 795         ENTRY;
 796
 797         if (stripe_cnt_min < 1)
 798                 RETURN(-EINVAL);
 799
 800         pool = lov_find_pool(lov, poolname);
 801         if (pool == NULL) {
 802                 osts = &(lov->lov_packed);
 803                 lqr = &(lov->lov_qos.lq_rr);
 804         } else {
 805                 cfs_down_read(&pool_tgt_rw_sem(pool));
 806                 osts = &(pool->pool_obds);
 807                 lqr = &(pool->pool_rr);
 808         }
 809
 810         obd_getref(exp->exp_obd);
 811
 812         /* wait for fresh statfs info if needed, the rpcs are sent in
 813          * lov_create() */
 814         qos_statfs_update(exp->exp_obd,
 815                           cfs_time_shift_64(-2 * lov->desc.ld_qos_maxage), 1);
 816
 817         /* Detect -EAGAIN early, before expensive lock is taken. */
 818         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 819                 GOTO(out_nolock, rc = -EAGAIN);
 820
 821         /* Do actual allocation, use write lock here. */
 822         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 823
 824         /*
 825          * Check again, while we were sleeping on @lq_rw_sem things could
 826          * change.
 827          */
 828         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 829                 GOTO(out, rc = -EAGAIN);
 830
 831         if (lov->desc.ld_active_tgt_count < 2)
 832                 GOTO(out, rc = -EAGAIN);
 833
 834         rc = qos_calc_ppo(exp->exp_obd);
 835         if (rc)
 836                 GOTO(out, rc);
 837
 838         good_osts = 0;
 839         /* Find all the OSTs that are valid stripe candidates */
 840         for (i = 0; i < osts->op_count; i++) {
 841                 if (!lov->lov_tgts[osts->op_array[i]] ||
 842                     !lov->lov_tgts[osts->op_array[i]]->ltd_active)
 843                         continue;
 844
 845                 /* Fail Check before osc_precreate() is called
 846                    so we can only 'fail' single OSC. */
 847                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && osts->op_array[i] == 0)
 848                         continue;
 849
 850                 if (obd_precreate(lov->lov_tgts[osts->op_array[i]]->ltd_exp) > 2)
 851                         continue;
 852
 853                 lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable = 1;
 854                 qos_calc_weight(lov, osts->op_array[i]);
 855                 total_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 856
 857                 good_osts++;
 858         }
 859
 860 #ifdef QOS_DEBUG
 861         CDEBUG(D_QOS, "found %d good osts\n", good_osts);
 862 #endif
 863
 864         if (good_osts < stripe_cnt_min)
 865                 GOTO(out, rc = -EAGAIN);
 866
 867         /* We have enough osts */
 868         if (good_osts < *stripe_cnt)
 869                 *stripe_cnt = good_osts;
 870
 871         if (!*stripe_cnt)
 872                 GOTO(out, rc = -EAGAIN);
 873
 874         /* Find enough OSTs with weighted random allocation. */
 875         nfound = 0;
 876         while (nfound < *stripe_cnt) {
 877                 __u64 rand, cur_weight;
 878
 879                 cur_weight = 0;
 880                 rc = -ENODEV;
 881
 882                 if (total_weight) {
 883 #if BITS_PER_LONG == 32
 884                         rand = cfs_rand() % (unsigned)total_weight;
 885                         /* If total_weight > 32-bit, first generate the high
 886                          * 32 bits of the random number, then add in the low
 887                          * 32 bits (truncated to the upper limit, if needed) */
 888                         if (total_weight > 0xffffffffULL)
 889                                 rand = (__u64)(cfs_rand() %
 890                                           (unsigned)(total_weight >> 32)) << 32;
 891                         else
 892                                 rand = 0;
 893
 894                         if (rand == (total_weight & 0xffffffff00000000ULL))
 895                                 rand |= cfs_rand() % (unsigned)total_weight;
 896                         else
 897                                 rand |= cfs_rand();
 898
 899 #else
 900                         rand = ((__u64)cfs_rand() << 32 | cfs_rand()) %
 901                                 total_weight;
 902 #endif
 903                 } else {
 904                         rand = 0;
 905                 }
 906
 907                 /* On average, this will hit larger-weighted osts more often.
 908                    0-weight osts will always get used last (only when rand=0).*/
 909                 for (i = 0; i < osts->op_count; i++) {
 910                         if (!lov->lov_tgts[osts->op_array[i]] ||
 911                             !lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable)
 912                                 continue;
 913
 914                         cur_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 915 #ifdef QOS_DEBUG
 916                         CDEBUG(D_QOS, "stripe_cnt=%d nfound=%d cur_weight="LPU64
 917                                       " rand="LPU64" total_weight="LPU64"\n",
 918                                *stripe_cnt, nfound, cur_weight, rand, total_weight);
 919 #endif
 920                         if (cur_weight >= rand) {
 921 #ifdef QOS_DEBUG
 922                                 CDEBUG(D_QOS, "assigned stripe=%d to idx=%d\n",
 923                                        nfound, osts->op_array[i]);
 924 #endif
 925                                 idx_arr[nfound++] = osts->op_array[i];
 926                                 qos_used(lov, osts, osts->op_array[i], &total_weight);
 927                                 rc = 0;
 928                                 break;
 929                         }
 930                 }
 931                 /* should never satisfy below condition */
 932                 if (rc) {
 933                         CERROR("Didn't find any OSTs?\n");
 934                         break;
 935                 }
 936         }
 937         LASSERT(nfound == *stripe_cnt);
 938
 939 out:
 940         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 941
 942 out_nolock:
 943         if (pool != NULL) {
 944                 cfs_up_read(&pool_tgt_rw_sem(pool));
 945                 /* put back ref got by lov_find_pool() */
 946                 lov_pool_putref(pool);
 947         }
 948
 949         if (rc == -EAGAIN)
 950                 rc = alloc_rr(lov, idx_arr, stripe_cnt, poolname, flags);
 951
 952         obd_putref(exp->exp_obd);
 953         RETURN(rc);
 954 }
 955
 956 /* return new alloced stripe count on success */
 957 static int alloc_idx_array(struct obd_export *exp, struct lov_stripe_md *lsm,
 958                            int newea, int **idx_arr, int *arr_cnt, int flags)
 959 {
 960         struct lov_obd *lov = &exp->exp_obd->u.lov;
 961         int stripe_cnt = lsm->lsm_stripe_count;
 962         int i, rc = 0;
 963         int *tmp_arr = NULL;
 964         ENTRY;
 965
 966         *arr_cnt = stripe_cnt;
 967         OBD_ALLOC(tmp_arr, *arr_cnt * sizeof(int));
 968         if (tmp_arr == NULL)
 969                 RETURN(-ENOMEM);
 970         for (i = 0; i < *arr_cnt; i++)
 971                 tmp_arr[i] = -1;
 972
 973         if (newea ||
 974             lsm->lsm_oinfo[0]->loi_ost_idx >= lov->desc.ld_tgt_count)
 975                 rc = alloc_qos(exp, tmp_arr, &stripe_cnt,
 976                                lsm->lsm_pool_name, flags);
 977         else
 978                 rc = alloc_specific(lov, lsm, tmp_arr);
 979
 980         if (rc)
 981                 GOTO(out_arr, rc);
 982
 983         *idx_arr = tmp_arr;
 984         RETURN(stripe_cnt);
 985 out_arr:
 986         OBD_FREE(tmp_arr, *arr_cnt * sizeof(int));
 987         *arr_cnt = 0;
 988         RETURN(rc);
 989 }
 990
 991 static void free_idx_array(int *idx_arr, int arr_cnt)
 992 {
 993         if (arr_cnt)
 994                 OBD_FREE(idx_arr, arr_cnt * sizeof(int));
 995 }
 996
 997 int qos_prep_create(struct obd_export *exp, struct lov_request_set *set)
 998 {
 999         struct lov_obd *lov = &exp->exp_obd->u.lov;
1000         struct lov_stripe_md *lsm;
1001         struct obdo *src_oa = set->set_oi->oi_oa;
1002         struct obd_trans_info *oti = set->set_oti;
1003         int i, stripes, rc = 0, newea = 0;
1004         int flag = LOV_USES_ASSIGNED_STRIPE;
1005         int *idx_arr = NULL, idx_cnt = 0;
1006         ENTRY;
1007
1008         LASSERT(src_oa->o_valid & OBD_MD_FLID);
1009         LASSERT(src_oa->o_valid & OBD_MD_FLGROUP);
1010
1011         if (set->set_oi->oi_md == NULL) {
1012                 int stripes_def = lov_get_stripecnt(lov, 0);
1013
1014                 /* If the MDS file was truncated up to some size, stripe over
1015                  * enough OSTs to allow the file to be created at that size.
1016                  * This may mean we use more than the default # of stripes. */
1017                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
1018                         obd_size min_bavail = LUSTRE_STRIPE_MAXBYTES;
1019
1020                         /* Find a small number of stripes we can use
1021                            (up to # of active osts). */
1022                         stripes = 1;
1023                         for (i = 0; i < lov->desc.ld_tgt_count; i++) {
1024                                 if (!lov->lov_tgts[i] ||
1025                                     !lov->lov_tgts[i]->ltd_active)
1026                                         continue;
1027                                 min_bavail = min(min_bavail, TGT_BAVAIL(i));
1028                                 if (min_bavail * stripes > src_oa->o_size)
1029                                         break;
1030                                 stripes++;
1031                         }
1032
1033                         if (stripes < stripes_def)
1034                                 stripes = stripes_def;
1035                 } else {
1036                          flag = LOV_USES_DEFAULT_STRIPE;
1037                          stripes = stripes_def;
1038                 }
1039
1040                 rc = lov_alloc_memmd(&set->set_oi->oi_md, stripes,
1041                                      lov->desc.ld_pattern ?
1042                                      lov->desc.ld_pattern : LOV_PATTERN_RAID0,
1043                                      LOV_MAGIC);
1044                 if (rc < 0)
1045                         GOTO(out_err, rc);
1046                 newea = 1;
1047                 rc = 0;
1048         }
1049
1050         lsm = set->set_oi->oi_md;
1051         lsm->lsm_object_id = src_oa->o_id;
1052         lsm->lsm_object_seq = src_oa->o_seq;
1053
1054         if (!lsm->lsm_stripe_size)
1055                 lsm->lsm_stripe_size = lov->desc.ld_default_stripe_size;
1056         if (!lsm->lsm_pattern) {
1057                 LASSERT(lov->desc.ld_pattern);
1058                 lsm->lsm_pattern = lov->desc.ld_pattern;
1059         }
1060
1061         stripes = alloc_idx_array(exp, lsm, newea, &idx_arr, &idx_cnt, flag);
1062         if (stripes <= 0)
1063                 GOTO(out_err, rc = stripes ? stripes : -EIO);
1064         LASSERTF(stripes <= lsm->lsm_stripe_count,"requested %d allocated %d\n",
1065                  lsm->lsm_stripe_count, stripes);
1066
1067         for (i = 0; i < stripes; i++) {
1068                 struct lov_request *req;
1069                 int ost_idx = idx_arr[i];
1070                 LASSERT(ost_idx >= 0);
1071
1072                 OBD_ALLOC(req, sizeof(*req));
1073                 if (req == NULL)
1074                         GOTO(out_err, rc = -ENOMEM);
1075                 lov_set_add_req(req, set);
1076
1077                 req->rq_buflen = sizeof(*req->rq_oi.oi_md);
1078                 OBD_ALLOC_LARGE(req->rq_oi.oi_md, req->rq_buflen);
1079                 if (req->rq_oi.oi_md == NULL)
1080                         GOTO(out_err, rc = -ENOMEM);
1081
1082                 OBDO_ALLOC(req->rq_oi.oi_oa);
1083                 if (req->rq_oi.oi_oa == NULL)
1084                         GOTO(out_err, rc = -ENOMEM);
1085
1086                 req->rq_idx = ost_idx;
1087                 req->rq_stripe = i;
1088                 /* create data objects with "parent" OA */
1089                 memcpy(req->rq_oi.oi_oa, src_oa, sizeof(*req->rq_oi.oi_oa));
1090                 req->rq_oi.oi_cb_up = cb_create_update;
1091
1092                 /* XXX When we start creating objects on demand, we need to
1093                  *     make sure that we always create the object on the
1094                  *     stripe which holds the existing file size.
1095                  */
1096                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
1097                         req->rq_oi.oi_oa->o_size =
1098                                 lov_size_to_stripe(lsm, src_oa->o_size, i);
1099
1100                         CDEBUG(D_INODE, "stripe %d has size "LPU64"/"LPU64"\n",
1101                                i, req->rq_oi.oi_oa->o_size, src_oa->o_size);
1102                 }
1103         }
1104         LASSERT(set->set_count == stripes);
1105
1106         if (stripes < lsm->lsm_stripe_count)
1107                 qos_shrink_lsm(set);
1108         if (OBD_FAIL_CHECK(OBD_FAIL_MDS_LOV_PREP_CREATE)) {
1109                 qos_shrink_lsm(set);
1110                 rc = -EIO;
1111         }
1112
1113         if (oti && (src_oa->o_valid & OBD_MD_FLCOOKIE)) {
1114                 oti_alloc_cookies(oti, set->set_count);
1115                 if (!oti->oti_logcookies)
1116                         GOTO(out_err, rc = -ENOMEM);
1117                 set->set_cookies = oti->oti_logcookies;
1118         }
1119 out_err:
1120         if (newea && rc)
1121                 obd_free_memmd(exp, &set->set_oi->oi_md);
1122         if (idx_arr)
1123                 free_idx_array(idx_arr, idx_cnt);
1124         EXIT;
1125         return rc;
1126 }
1127
1128 void qos_update(struct lov_obd *lov)
1129 {
1130         ENTRY;
1131         lov->lov_qos.lq_dirty = 1;
1132 }
1133
1134 void qos_statfs_done(struct lov_obd *lov)
1135 {
1136         LASSERT(lov->lov_qos.lq_statfs_in_progress);
1137         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1138         lov->lov_qos.lq_statfs_in_progress = 0;
1139         /* wake up any threads waiting for the statfs rpcs to complete */
1140         cfs_waitq_signal(&lov->lov_qos.lq_statfs_waitq);
1141         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1142 }
1143
1144 static int qos_statfs_ready(struct obd_device *obd, __u64 max_age)
1145 {
1146         struct lov_obd         *lov = &obd->u.lov;
1147         int rc;
1148         ENTRY;
1149         cfs_down_read(&lov->lov_qos.lq_rw_sem);
1150         rc = lov->lov_qos.lq_statfs_in_progress == 0 ||
1151              cfs_time_beforeq_64(max_age, obd->obd_osfs_age);
1152         cfs_up_read(&lov->lov_qos.lq_rw_sem);
1153         RETURN(rc);
1154 }
1155
1156 /*
1157  * Update statfs data if the current osfs age is older than max_age.
1158  * If wait is not set, it means that we are called from lov_create()
1159  * and we should just issue the rpcs without waiting for them to complete.
1160  * If wait is set, we are called from alloc_qos() and we just have
1161  * to wait for the request set to complete.
1162  */
1163 void qos_statfs_update(struct obd_device *obd, __u64 max_age, int wait)
1164 {
1165         struct lov_obd         *lov = &obd->u.lov;
1166         struct obd_info        *oinfo;
1167         int                     rc = 0;
1168         struct ptlrpc_request_set *set = NULL;
1169         ENTRY;
1170
1171         if (cfs_time_beforeq_64(max_age, obd->obd_osfs_age))
1172                 /* statfs data are quite recent, don't need to refresh it */
1173                 RETURN_EXIT;
1174
1175         if (!wait && lov->lov_qos.lq_statfs_in_progress)
1176                 /* statfs already in progress */
1177                 RETURN_EXIT;
1178
1179         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1180         if (lov->lov_qos.lq_statfs_in_progress) {
1181                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
1182                 GOTO(out, rc = 0);
1183         }
1184         /* no statfs in flight, send rpcs */
1185         lov->lov_qos.lq_statfs_in_progress = 1;
1186         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1187
1188         if (wait)
1189                 CDEBUG(D_QOS, "%s: did not manage to get fresh statfs data "
1190                        "in a timely manner (osfs age "LPU64", max age "LPU64")"
1191                        ", sending new statfs rpcs\n",
1192                        obd_uuid2str(&lov->desc.ld_uuid), obd->obd_osfs_age,
1193                        max_age);
1194
1195         /* need to send statfs rpcs */
1196         CDEBUG(D_QOS, "sending new statfs requests\n");
1197         memset(lov->lov_qos.lq_statfs_data, 0,
1198                sizeof(*lov->lov_qos.lq_statfs_data));
1199         oinfo = &lov->lov_qos.lq_statfs_data->lsd_oi;
1200         oinfo->oi_osfs = &lov->lov_qos.lq_statfs_data->lsd_statfs;
1201         oinfo->oi_flags = OBD_STATFS_NODELAY;
1202         set = ptlrpc_prep_set();
1203         if (!set)
1204                 GOTO(out_failed, rc = -ENOMEM);
1205
1206         rc = obd_statfs_async(obd, oinfo, max_age, set);
1207         if (rc || cfs_list_empty(&set->set_requests)) {
1208                 if (rc)
1209                         CWARN("statfs failed with %d\n", rc);
1210                 GOTO(out_failed, rc);
1211         }
1212         /* send requests via ptlrpcd */
1213         oinfo->oi_flags |= OBD_STATFS_PTLRPCD;
1214         ptlrpcd_add_rqset(set);
1215         GOTO(out, rc);
1216
1217 out_failed:
1218         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1219         lov->lov_qos.lq_statfs_in_progress = 0;
1220         /* wake up any threads waiting for the statfs rpcs to complete */
1221         cfs_waitq_signal(&lov->lov_qos.lq_statfs_waitq);
1222         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1223         wait = 0;
1224 out:
1225         if (set)
1226                 ptlrpc_set_destroy(set);
1227         if (wait) {
1228                 struct l_wait_info lwi = { 0 };
1229                 CDEBUG(D_QOS, "waiting for statfs requests to complete\n");
1230                 l_wait_event(lov->lov_qos.lq_statfs_waitq,
1231                              qos_statfs_ready(obd, max_age), &lwi);
1232                 if (cfs_time_before_64(obd->obd_osfs_age, max_age))
1233                         CDEBUG(D_QOS, "%s: still no fresh statfs data after "
1234                                       "waiting (osfs age "LPU64", max age "
1235                                       LPU64")\n",
1236                                       obd_uuid2str(&lov->desc.ld_uuid),
1237                                       obd->obd_osfs_age, max_age);
1238         }
1239 }