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(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(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(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 = 0, 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; i < ost_count; i++, ost_idx = osts->op_array[i]) {
 550                         rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 551                                                          set->set_oti);
 552                         if (rc == 0)
 553                                 break;
 554                 }
 555                 cfs_up_read(&pool_tgt_rw_sem(pool));
 556                 lov_pool_putref(pool);
 557                 RETURN(rc);
 558         }
 559
 560         ost_count = lov->desc.ld_tgt_count;
 561         /* Then check whether we can create the objects on other OSTs */
 562         ost_idx = (req->rq_idx + lsm->lsm_stripe_count) % ost_count;
 563         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
 564                 rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 565                                                  set->set_oti);
 566
 567                 if (rc == 0)
 568                         break;
 569         }
 570
 571         RETURN(rc);
 572 }
 573
 574 static int min_stripe_count(int stripe_cnt, int flags)
 575 {
 576         return (flags & LOV_USES_DEFAULT_STRIPE ?
 577                 stripe_cnt - (stripe_cnt / 4) : stripe_cnt);
 578 }
 579
 580 #define LOV_CREATE_RESEED_MULT 4
 581 #define LOV_CREATE_RESEED_MIN  1000
 582 /* Allocate objects on osts with round-robin algorithm */
 583 static int alloc_rr(struct lov_obd *lov, int *idx_arr, int *stripe_cnt,
 584                     char *poolname, int flags)
 585 {
 586         unsigned array_idx;
 587         int i, rc, *idx_pos;
 588         __u32 ost_idx;
 589         int ost_start_idx_temp;
 590         int speed = 0;
 591         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 592         struct pool_desc *pool;
 593         struct ost_pool *osts;
 594         struct lov_qos_rr *lqr;
 595         ENTRY;
 596
 597         pool = lov_find_pool(lov, poolname);
 598         if (pool == NULL) {
 599                 osts = &(lov->lov_packed);
 600                 lqr = &(lov->lov_qos.lq_rr);
 601         } else {
 602                 cfs_down_read(&pool_tgt_rw_sem(pool));
 603                 osts = &(pool->pool_obds);
 604                 lqr = &(pool->pool_rr);
 605         }
 606
 607         rc = qos_calc_rr(lov, osts, lqr);
 608         if (rc)
 609                 GOTO(out, rc);
 610
 611         if (--lqr->lqr_start_count <= 0) {
 612                 lqr->lqr_start_idx = cfs_rand() % osts->op_count;
 613                 lqr->lqr_start_count =
 614                         (LOV_CREATE_RESEED_MIN / max(osts->op_count, 1U) +
 615                          LOV_CREATE_RESEED_MULT) * max(osts->op_count, 1U);
 616         } else if (stripe_cnt_min >= osts->op_count ||
 617                    lqr->lqr_start_idx > osts->op_count) {
 618                 /* If we have allocated from all of the OSTs, slowly
 619                  * precess the next start if the OST/stripe count isn't
 620                  * already doing this for us. */
 621                 lqr->lqr_start_idx %= osts->op_count;
 622                 if (*stripe_cnt > 1 && (osts->op_count % (*stripe_cnt)) != 1)
 623                         ++lqr->lqr_offset_idx;
 624         }
 625         cfs_down_read(&lov->lov_qos.lq_rw_sem);
 626         ost_start_idx_temp = lqr->lqr_start_idx;
 627
 628 repeat_find:
 629         array_idx = (lqr->lqr_start_idx + lqr->lqr_offset_idx) % osts->op_count;
 630         idx_pos = idx_arr;
 631 #ifdef QOS_DEBUG
 632         CDEBUG(D_QOS, "pool '%s' want %d startidx %d startcnt %d offset %d "
 633                "active %d count %d arrayidx %d\n", poolname,
 634                *stripe_cnt, lqr->lqr_start_idx, lqr->lqr_start_count,
 635                lqr->lqr_offset_idx, osts->op_count, osts->op_count, array_idx);
 636 #endif
 637
 638         for (i = 0; i < osts->op_count;
 639                     i++, array_idx=(array_idx + 1) % osts->op_count) {
 640                 ++lqr->lqr_start_idx;
 641                 ost_idx = lqr->lqr_pool.op_array[array_idx];
 642 #ifdef QOS_DEBUG
 643                 CDEBUG(D_QOS, "#%d strt %d act %d strp %d ary %d idx %d\n",
 644                        i, lqr->lqr_start_idx,
 645                        ((ost_idx != LOV_QOS_EMPTY) && lov->lov_tgts[ost_idx]) ?
 646                        lov->lov_tgts[ost_idx]->ltd_active : 0,
 647                        idx_pos - idx_arr, array_idx, ost_idx);
 648 #endif
 649                 if ((ost_idx == LOV_QOS_EMPTY) || !lov->lov_tgts[ost_idx] ||
 650                     !lov->lov_tgts[ost_idx]->ltd_active)
 651                         continue;
 652
 653                 /* Fail Check before osc_precreate() is called
 654                    so we can only 'fail' single OSC. */
 655                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 656                         continue;
 657
 658                 /* Drop slow OSCs if we can */
 659                 if (obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed)
 660                         continue;
 661
 662                 *idx_pos = ost_idx;
 663                 idx_pos++;
 664                 /* We have enough stripes */
 665                 if (idx_pos - idx_arr == *stripe_cnt)
 666                         break;
 667         }
 668         if ((speed < 2) && (idx_pos - idx_arr < stripe_cnt_min)) {
 669                 /* Try again, allowing slower OSCs */
 670                 speed++;
 671                 lqr->lqr_start_idx = ost_start_idx_temp;
 672                 goto repeat_find;
 673         }
 674
 675         cfs_up_read(&lov->lov_qos.lq_rw_sem);
 676
 677         *stripe_cnt = idx_pos - idx_arr;
 678 out:
 679         if (pool != NULL) {
 680                 cfs_up_read(&pool_tgt_rw_sem(pool));
 681                 /* put back ref got by lov_find_pool() */
 682                 lov_pool_putref(pool);
 683         }
 684
 685         RETURN(rc);
 686 }
 687
 688 /* alloc objects on osts with specific stripe offset */
 689 static int alloc_specific(struct lov_obd *lov, struct lov_stripe_md *lsm,
 690                           int *idx_arr)
 691 {
 692         unsigned ost_idx, array_idx, ost_count;
 693         int i, rc, *idx_pos;
 694         int speed = 0;
 695         struct pool_desc *pool;
 696         struct ost_pool *osts;
 697         ENTRY;
 698
 699         pool = lov_find_pool(lov, lsm->lsm_pool_name);
 700         if (pool == NULL) {
 701                 osts = &(lov->lov_packed);
 702         } else {
 703                 cfs_down_read(&pool_tgt_rw_sem(pool));
 704                 osts = &(pool->pool_obds);
 705         }
 706
 707         ost_count = osts->op_count;
 708
 709 repeat_find:
 710         /* search loi_ost_idx in ost array */
 711         array_idx = 0;
 712         for (i = 0; i < ost_count; i++) {
 713                 if (osts->op_array[i] == lsm->lsm_oinfo[0]->loi_ost_idx) {
 714                         array_idx = i;
 715                         break;
 716                 }
 717         }
 718         if (i == ost_count) {
 719                 CERROR("Start index %d not found in pool '%s'\n",
 720                        lsm->lsm_oinfo[0]->loi_ost_idx, lsm->lsm_pool_name);
 721                 GOTO(out, rc = -EINVAL);
 722         }
 723
 724         idx_pos = idx_arr;
 725         for (i = 0; i < ost_count;
 726              i++, array_idx = (array_idx + 1) % ost_count) {
 727                 ost_idx = osts->op_array[array_idx];
 728
 729                 if (!lov->lov_tgts[ost_idx] ||
 730                     !lov->lov_tgts[ost_idx]->ltd_active) {
 731                         continue;
 732                 }
 733
 734                 /* Fail Check before osc_precreate() is called
 735                    so we can only 'fail' single OSC. */
 736                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 737                         continue;
 738
 739                 /* Drop slow OSCs if we can, but not for requested start idx.
 740                  *
 741                  * This means "if OSC is slow and it is not the requested
 742                  * start OST, then it can be skipped, otherwise skip it only
 743                  * if it is inactive/recovering/out-of-space." */
 744                 if ((obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed) &&
 745                     (i != 0 || speed >= 2))
 746                         continue;
 747
 748                 *idx_pos = ost_idx;
 749                 idx_pos++;
 750                 /* We have enough stripes */
 751                 if (idx_pos - idx_arr == lsm->lsm_stripe_count)
 752                         GOTO(out, rc = 0);
 753         }
 754         if (speed < 2) {
 755                 /* Try again, allowing slower OSCs */
 756                 speed++;
 757                 goto repeat_find;
 758         }
 759
 760         /* If we were passed specific striping params, then a failure to
 761          * meet those requirements is an error, since we can't reallocate
 762          * that memory (it might be part of a larger array or something).
 763          *
 764          * We can only get here if lsm_stripe_count was originally > 1.
 765          */
 766         CERROR("can't lstripe objid "LPX64": have %d want %u\n",
 767                lsm->lsm_object_id, (int)(idx_pos - idx_arr),
 768                lsm->lsm_stripe_count);
 769         rc = -EFBIG;
 770 out:
 771         if (pool != NULL) {
 772                 cfs_up_read(&pool_tgt_rw_sem(pool));
 773                 /* put back ref got by lov_find_pool() */
 774                 lov_pool_putref(pool);
 775         }
 776
 777         RETURN(rc);
 778 }
 779
 780 /* Alloc objects on osts with optimization based on:
 781    - free space
 782    - network resources (shared OSS's)
 783 */
 784 static int alloc_qos(struct obd_export *exp, int *idx_arr, int *stripe_cnt,
 785                      char *poolname, int flags)
 786 {
 787         struct lov_obd *lov = &exp->exp_obd->u.lov;
 788         __u64 total_weight = 0;
 789         int nfound, good_osts, i, rc = 0;
 790         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 791         struct pool_desc *pool;
 792         struct ost_pool *osts;
 793         struct lov_qos_rr *lqr;
 794         ENTRY;
 795
 796         if (stripe_cnt_min < 1)
 797                 RETURN(-EINVAL);
 798
 799         pool = lov_find_pool(lov, poolname);
 800         if (pool == NULL) {
 801                 osts = &(lov->lov_packed);
 802                 lqr = &(lov->lov_qos.lq_rr);
 803         } else {
 804                 cfs_down_read(&pool_tgt_rw_sem(pool));
 805                 osts = &(pool->pool_obds);
 806                 lqr = &(pool->pool_rr);
 807         }
 808
 809         obd_getref(exp->exp_obd);
 810
 811         /* wait for fresh statfs info if needed, the rpcs are sent in
 812          * lov_create() */
 813         qos_statfs_update(exp->exp_obd,
 814                           cfs_time_shift_64(-2 * lov->desc.ld_qos_maxage), 1);
 815
 816         /* Detect -EAGAIN early, before expensive lock is taken. */
 817         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 818                 GOTO(out_nolock, rc = -EAGAIN);
 819
 820         /* Do actual allocation, use write lock here. */
 821         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 822
 823         /*
 824          * Check again, while we were sleeping on @lq_rw_sem things could
 825          * change.
 826          */
 827         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 828                 GOTO(out, rc = -EAGAIN);
 829
 830         if (lov->desc.ld_active_tgt_count < 2)
 831                 GOTO(out, rc = -EAGAIN);
 832
 833         rc = qos_calc_ppo(exp->exp_obd);
 834         if (rc)
 835                 GOTO(out, rc);
 836
 837         good_osts = 0;
 838         /* Find all the OSTs that are valid stripe candidates */
 839         for (i = 0; i < osts->op_count; i++) {
 840                 if (!lov->lov_tgts[osts->op_array[i]] ||
 841                     !lov->lov_tgts[osts->op_array[i]]->ltd_active)
 842                         continue;
 843
 844                 /* Fail Check before osc_precreate() is called
 845                    so we can only 'fail' single OSC. */
 846                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && osts->op_array[i] == 0)
 847                         continue;
 848
 849                 if (obd_precreate(lov->lov_tgts[osts->op_array[i]]->ltd_exp) > 2)
 850                         continue;
 851
 852                 lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable = 1;
 853                 qos_calc_weight(lov, osts->op_array[i]);
 854                 total_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 855
 856                 good_osts++;
 857         }
 858
 859 #ifdef QOS_DEBUG
 860         CDEBUG(D_QOS, "found %d good osts\n", good_osts);
 861 #endif
 862
 863         if (good_osts < stripe_cnt_min)
 864                 GOTO(out, rc = -EAGAIN);
 865
 866         /* We have enough osts */
 867         if (good_osts < *stripe_cnt)
 868                 *stripe_cnt = good_osts;
 869
 870         if (!*stripe_cnt)
 871                 GOTO(out, rc = -EAGAIN);
 872
 873         /* Find enough OSTs with weighted random allocation. */
 874         nfound = 0;
 875         while (nfound < *stripe_cnt) {
 876                 __u64 rand, cur_weight;
 877
 878                 cur_weight = 0;
 879                 rc = -ENODEV;
 880
 881                 if (total_weight) {
 882 #if BITS_PER_LONG == 32
 883                         rand = cfs_rand() % (unsigned)total_weight;
 884                         /* If total_weight > 32-bit, first generate the high
 885                          * 32 bits of the random number, then add in the low
 886                          * 32 bits (truncated to the upper limit, if needed) */
 887                         if (total_weight > 0xffffffffULL)
 888                                 rand = (__u64)(cfs_rand() %
 889                                           (unsigned)(total_weight >> 32)) << 32;
 890                         else
 891                                 rand = 0;
 892
 893                         if (rand == (total_weight & 0xffffffff00000000ULL))
 894                                 rand |= cfs_rand() % (unsigned)total_weight;
 895                         else
 896                                 rand |= cfs_rand();
 897
 898 #else
 899                         rand = ((__u64)cfs_rand() << 32 | cfs_rand()) %
 900                                 total_weight;
 901 #endif
 902                 } else {
 903                         rand = 0;
 904                 }
 905
 906                 /* On average, this will hit larger-weighted osts more often.
 907                    0-weight osts will always get used last (only when rand=0).*/
 908                 for (i = 0; i < osts->op_count; i++) {
 909                         if (!lov->lov_tgts[osts->op_array[i]] ||
 910                             !lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable)
 911                                 continue;
 912
 913                         cur_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 914 #ifdef QOS_DEBUG
 915                         CDEBUG(D_QOS, "stripe_cnt=%d nfound=%d cur_weight="LPU64
 916                                       " rand="LPU64" total_weight="LPU64"\n",
 917                                *stripe_cnt, nfound, cur_weight, rand, total_weight);
 918 #endif
 919                         if (cur_weight >= rand) {
 920 #ifdef QOS_DEBUG
 921                                 CDEBUG(D_QOS, "assigned stripe=%d to idx=%d\n",
 922                                        nfound, osts->op_array[i]);
 923 #endif
 924                                 idx_arr[nfound++] = osts->op_array[i];
 925                                 qos_used(lov, osts, osts->op_array[i], &total_weight);
 926                                 rc = 0;
 927                                 break;
 928                         }
 929                 }
 930                 /* should never satisfy below condition */
 931                 if (rc) {
 932                         CERROR("Didn't find any OSTs?\n");
 933                         break;
 934                 }
 935         }
 936         LASSERT(nfound == *stripe_cnt);
 937
 938 out:
 939         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 940
 941 out_nolock:
 942         if (pool != NULL) {
 943                 cfs_up_read(&pool_tgt_rw_sem(pool));
 944                 /* put back ref got by lov_find_pool() */
 945                 lov_pool_putref(pool);
 946         }
 947
 948         if (rc == -EAGAIN)
 949                 rc = alloc_rr(lov, idx_arr, stripe_cnt, poolname, flags);
 950
 951         obd_putref(exp->exp_obd);
 952         RETURN(rc);
 953 }
 954
 955 /* return new alloced stripe count on success */
 956 static int alloc_idx_array(struct obd_export *exp, struct lov_stripe_md *lsm,
 957                            int newea, int **idx_arr, int *arr_cnt, int flags)
 958 {
 959         struct lov_obd *lov = &exp->exp_obd->u.lov;
 960         int stripe_cnt = lsm->lsm_stripe_count;
 961         int i, rc = 0;
 962         int *tmp_arr = NULL;
 963         ENTRY;
 964
 965         *arr_cnt = stripe_cnt;
 966         OBD_ALLOC(tmp_arr, *arr_cnt * sizeof(int));
 967         if (tmp_arr == NULL)
 968                 RETURN(-ENOMEM);
 969         for (i = 0; i < *arr_cnt; i++)
 970                 tmp_arr[i] = -1;
 971
 972         if (newea ||
 973             lsm->lsm_oinfo[0]->loi_ost_idx >= lov->desc.ld_tgt_count)
 974                 rc = alloc_qos(exp, tmp_arr, &stripe_cnt,
 975                                lsm->lsm_pool_name, flags);
 976         else
 977                 rc = alloc_specific(lov, lsm, tmp_arr);
 978
 979         if (rc)
 980                 GOTO(out_arr, rc);
 981
 982         *idx_arr = tmp_arr;
 983         RETURN(stripe_cnt);
 984 out_arr:
 985         OBD_FREE(tmp_arr, *arr_cnt * sizeof(int));
 986         *arr_cnt = 0;
 987         RETURN(rc);
 988 }
 989
 990 static void free_idx_array(int *idx_arr, int arr_cnt)
 991 {
 992         if (arr_cnt)
 993                 OBD_FREE(idx_arr, arr_cnt * sizeof(int));
 994 }
 995
 996 int qos_prep_create(struct obd_export *exp, struct lov_request_set *set)
 997 {
 998         struct lov_obd *lov = &exp->exp_obd->u.lov;
 999         struct lov_stripe_md *lsm;
1000         struct obdo *src_oa = set->set_oi->oi_oa;
1001         struct obd_trans_info *oti = set->set_oti;
1002         int i, stripes, rc = 0, newea = 0;
1003         int flag = LOV_USES_ASSIGNED_STRIPE;
1004         int *idx_arr = NULL, idx_cnt = 0;
1005         ENTRY;
1006
1007         LASSERT(src_oa->o_valid & OBD_MD_FLID);
1008         LASSERT(src_oa->o_valid & OBD_MD_FLGROUP);
1009
1010         if (set->set_oi->oi_md == NULL) {
1011                 int stripes_def = lov_get_stripecnt(lov, 0);
1012
1013                 /* If the MDS file was truncated up to some size, stripe over
1014                  * enough OSTs to allow the file to be created at that size.
1015                  * This may mean we use more than the default # of stripes. */
1016                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
1017                         obd_size min_bavail = LUSTRE_STRIPE_MAXBYTES;
1018
1019                         /* Find a small number of stripes we can use
1020                            (up to # of active osts). */
1021                         stripes = 1;
1022                         for (i = 0; i < lov->desc.ld_tgt_count; i++) {
1023                                 if (!lov->lov_tgts[i] ||
1024                                     !lov->lov_tgts[i]->ltd_active)
1025                                         continue;
1026                                 min_bavail = min(min_bavail, TGT_BAVAIL(i));
1027                                 if (min_bavail * stripes > src_oa->o_size)
1028                                         break;
1029                                 stripes++;
1030                         }
1031
1032                         if (stripes < stripes_def)
1033                                 stripes = stripes_def;
1034                 } else {
1035                          flag = LOV_USES_DEFAULT_STRIPE;
1036                          stripes = stripes_def;
1037                 }
1038
1039                 rc = lov_alloc_memmd(&set->set_oi->oi_md, stripes,
1040                                      lov->desc.ld_pattern ?
1041                                      lov->desc.ld_pattern : LOV_PATTERN_RAID0,
1042                                      LOV_MAGIC);
1043                 if (rc < 0)
1044                         GOTO(out_err, rc);
1045                 newea = 1;
1046                 rc = 0;
1047         }
1048
1049         lsm = set->set_oi->oi_md;
1050         lsm->lsm_object_id = src_oa->o_id;
1051         lsm->lsm_object_seq = src_oa->o_seq;
1052
1053         if (!lsm->lsm_stripe_size)
1054                 lsm->lsm_stripe_size = lov->desc.ld_default_stripe_size;
1055         if (!lsm->lsm_pattern) {
1056                 LASSERT(lov->desc.ld_pattern);
1057                 lsm->lsm_pattern = lov->desc.ld_pattern;
1058         }
1059
1060         stripes = alloc_idx_array(exp, lsm, newea, &idx_arr, &idx_cnt, flag);
1061         if (stripes <= 0)
1062                 GOTO(out_err, rc = stripes ? stripes : -EIO);
1063         LASSERTF(stripes <= lsm->lsm_stripe_count,"requested %d allocated %d\n",
1064                  lsm->lsm_stripe_count, stripes);
1065
1066         for (i = 0; i < stripes; i++) {
1067                 struct lov_request *req;
1068                 int ost_idx = idx_arr[i];
1069                 LASSERT(ost_idx >= 0);
1070
1071                 OBD_ALLOC(req, sizeof(*req));
1072                 if (req == NULL)
1073                         GOTO(out_err, rc = -ENOMEM);
1074                 lov_set_add_req(req, set);
1075
1076                 req->rq_buflen = sizeof(*req->rq_oi.oi_md);
1077                 OBD_ALLOC(req->rq_oi.oi_md, req->rq_buflen);
1078                 if (req->rq_oi.oi_md == NULL)
1079                         GOTO(out_err, rc = -ENOMEM);
1080
1081                 OBDO_ALLOC(req->rq_oi.oi_oa);
1082                 if (req->rq_oi.oi_oa == NULL)
1083                         GOTO(out_err, rc = -ENOMEM);
1084
1085                 req->rq_idx = ost_idx;
1086                 req->rq_stripe = i;
1087                 /* create data objects with "parent" OA */
1088                 memcpy(req->rq_oi.oi_oa, src_oa, sizeof(*req->rq_oi.oi_oa));
1089                 req->rq_oi.oi_cb_up = cb_create_update;
1090
1091                 /* XXX When we start creating objects on demand, we need to
1092                  *     make sure that we always create the object on the
1093                  *     stripe which holds the existing file size.
1094                  */
1095                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
1096                         req->rq_oi.oi_oa->o_size =
1097                                 lov_size_to_stripe(lsm, src_oa->o_size, i);
1098
1099                         CDEBUG(D_INODE, "stripe %d has size "LPU64"/"LPU64"\n",
1100                                i, req->rq_oi.oi_oa->o_size, src_oa->o_size);
1101                 }
1102         }
1103         LASSERT(set->set_count == stripes);
1104
1105         if (stripes < lsm->lsm_stripe_count)
1106                 qos_shrink_lsm(set);
1107         if (OBD_FAIL_CHECK(OBD_FAIL_MDS_LOV_PREP_CREATE)) {
1108                 qos_shrink_lsm(set);
1109                 rc = -EIO;
1110         }
1111
1112         if (oti && (src_oa->o_valid & OBD_MD_FLCOOKIE)) {
1113                 oti_alloc_cookies(oti, set->set_count);
1114                 if (!oti->oti_logcookies)
1115                         GOTO(out_err, rc = -ENOMEM);
1116                 set->set_cookies = oti->oti_logcookies;
1117         }
1118 out_err:
1119         if (newea && rc)
1120                 obd_free_memmd(exp, &set->set_oi->oi_md);
1121         if (idx_arr)
1122                 free_idx_array(idx_arr, idx_cnt);
1123         EXIT;
1124         return rc;
1125 }
1126
1127 void qos_update(struct lov_obd *lov)
1128 {
1129         ENTRY;
1130         lov->lov_qos.lq_dirty = 1;
1131 }
1132
1133 void qos_statfs_done(struct lov_obd *lov)
1134 {
1135         LASSERT(lov->lov_qos.lq_statfs_in_progress);
1136         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1137         lov->lov_qos.lq_statfs_in_progress = 0;
1138         /* wake up any threads waiting for the statfs rpcs to complete */
1139         cfs_waitq_signal(&lov->lov_qos.lq_statfs_waitq);
1140         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1141 }
1142
1143 static int qos_statfs_ready(struct obd_device *obd, __u64 max_age)
1144 {
1145         struct lov_obd         *lov = &obd->u.lov;
1146         int rc;
1147         ENTRY;
1148         cfs_down_read(&lov->lov_qos.lq_rw_sem);
1149         rc = lov->lov_qos.lq_statfs_in_progress == 0 ||
1150              cfs_time_beforeq_64(max_age, obd->obd_osfs_age);
1151         cfs_up_read(&lov->lov_qos.lq_rw_sem);
1152         RETURN(rc);
1153 }
1154
1155 /*
1156  * Update statfs data if the current osfs age is older than max_age.
1157  * If wait is not set, it means that we are called from lov_create()
1158  * and we should just issue the rpcs without waiting for them to complete.
1159  * If wait is set, we are called from alloc_qos() and we just have
1160  * to wait for the request set to complete.
1161  */
1162 void qos_statfs_update(struct obd_device *obd, __u64 max_age, int wait)
1163 {
1164         struct lov_obd         *lov = &obd->u.lov;
1165         struct obd_info        *oinfo;
1166         int                     rc = 0;
1167         struct ptlrpc_request_set *set = NULL;
1168         ENTRY;
1169
1170         if (cfs_time_beforeq_64(max_age, obd->obd_osfs_age))
1171                 /* statfs data are quite recent, don't need to refresh it */
1172                 RETURN_EXIT;
1173
1174         if (!wait && lov->lov_qos.lq_statfs_in_progress)
1175                 /* statfs already in progress */
1176                 RETURN_EXIT;
1177
1178         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1179         if (lov->lov_qos.lq_statfs_in_progress) {
1180                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
1181                 GOTO(out, rc = 0);
1182         }
1183         /* no statfs in flight, send rpcs */
1184         lov->lov_qos.lq_statfs_in_progress = 1;
1185         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1186
1187         if (wait)
1188                 CDEBUG(D_QOS, "%s: did not manage to get fresh statfs data "
1189                        "in a timely manner (osfs age "LPU64", max age "LPU64")"
1190                        ", sending new statfs rpcs\n",
1191                        obd_uuid2str(&lov->desc.ld_uuid), obd->obd_osfs_age,
1192                        max_age);
1193
1194         /* need to send statfs rpcs */
1195         CDEBUG(D_QOS, "sending new statfs requests\n");
1196         memset(lov->lov_qos.lq_statfs_data, 0,
1197                sizeof(*lov->lov_qos.lq_statfs_data));
1198         oinfo = &lov->lov_qos.lq_statfs_data->lsd_oi;
1199         oinfo->oi_osfs = &lov->lov_qos.lq_statfs_data->lsd_statfs;
1200         oinfo->oi_flags = OBD_STATFS_NODELAY;
1201         set = ptlrpc_prep_set();
1202         if (!set)
1203                 GOTO(out_failed, rc = -ENOMEM);
1204
1205         rc = obd_statfs_async(obd, oinfo, max_age, set);
1206         if (rc || cfs_list_empty(&set->set_requests)) {
1207                 if (rc)
1208                         CWARN("statfs failed with %d\n", rc);
1209                 GOTO(out_failed, rc);
1210         }
1211         /* send requests via ptlrpcd */
1212         oinfo->oi_flags |= OBD_STATFS_PTLRPCD;
1213         ptlrpcd_add_rqset(set);
1214         GOTO(out, rc);
1215
1216 out_failed:
1217         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1218         lov->lov_qos.lq_statfs_in_progress = 0;
1219         /* wake up any threads waiting for the statfs rpcs to complete */
1220         cfs_waitq_signal(&lov->lov_qos.lq_statfs_waitq);
1221         cfs_up_write(&lov->lov_qos.lq_rw_sem);
1222         wait = 0;
1223 out:
1224         if (set)
1225                 ptlrpc_set_destroy(set);
1226         if (wait) {
1227                 struct l_wait_info lwi = { 0 };
1228                 CDEBUG(D_QOS, "waiting for statfs requests to complete\n");
1229                 l_wait_event(lov->lov_qos.lq_statfs_waitq,
1230                              qos_statfs_ready(obd, max_age), &lwi);
1231                 if (cfs_time_before_64(obd->obd_osfs_age, max_age))
1232                         CDEBUG(D_QOS, "%s: still no fresh statfs data after "
1233                                       "waiting (osfs age "LPU64", max age "
1234                                       LPU64")\n",
1235                                       obd_uuid2str(&lov->desc.ld_uuid),
1236                                       obd->obd_osfs_age, max_age);
1237         }
1238 }