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,
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  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  * Copyright (c) 2011, 2012, Whamcloud, Inc.
  33  */
  34 /*
  35  * This file is part of Lustre, http://www.lustre.org/
  36  * Lustre is a trademark of Sun Microsystems, Inc.
  37  */
  38
  39 #ifndef EXPORT_SYMTAB
  40 # define EXPORT_SYMTAB
  41 #endif
  42 #define DEBUG_SUBSYSTEM S_LOV
  43
  44 #ifdef __KERNEL__
  45 #include <libcfs/libcfs.h>
  46 #else
  47 #include <liblustre.h>
  48 #endif
  49
  50 #include <obd_class.h>
  51 #include <obd_lov.h>
  52 #include <lustre/lustre_idl.h>
  53 #include "lov_internal.h"
  54
  55 /* #define QOS_DEBUG 1 */
  56 #define D_QOS D_OTHER
  57
  58 #define TGT_BAVAIL(i) (lov->lov_tgts[i]->ltd_exp->exp_obd->obd_osfs.os_bavail *\
  59                        lov->lov_tgts[i]->ltd_exp->exp_obd->obd_osfs.os_bsize)
  60
  61
  62 int qos_add_tgt(struct obd_device *obd, __u32 index)
  63 {
  64         struct lov_obd *lov = &obd->u.lov;
  65         struct lov_qos_oss *oss, *temposs;
  66         struct obd_export *exp = lov->lov_tgts[index]->ltd_exp;
  67         int rc = 0, found = 0;
  68         ENTRY;
  69
  70         /* We only need this QOS struct on MDT, not clients - but we may not
  71          * have registered the LOV's observer yet, so there's no way to know */
  72         if (!exp || !exp->exp_connection) {
  73                 CERROR("Missing connection\n");
  74                 RETURN(-ENOTCONN);
  75         }
  76
  77         cfs_down_write(&lov->lov_qos.lq_rw_sem);
  78         cfs_mutex_down(&lov->lov_lock);
  79         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
  80                 if (obd_uuid_equals(&oss->lqo_uuid,
  81                                     &exp->exp_connection->c_remote_uuid)) {
  82                         found++;
  83                         break;
  84                 }
  85         }
  86
  87         if (!found) {
  88                 OBD_ALLOC_PTR(oss);
  89                 if (!oss)
  90                         GOTO(out, rc = -ENOMEM);
  91                 memcpy(&oss->lqo_uuid,
  92                        &exp->exp_connection->c_remote_uuid,
  93                        sizeof(oss->lqo_uuid));
  94         } else {
  95                 /* Assume we have to move this one */
  96                 cfs_list_del(&oss->lqo_oss_list);
  97         }
  98
  99         oss->lqo_ost_count++;
 100         lov->lov_tgts[index]->ltd_qos.ltq_oss = oss;
 101
 102         /* Add sorted by # of OSTs.  Find the first entry that we're
 103            bigger than... */
 104         cfs_list_for_each_entry(temposs, &lov->lov_qos.lq_oss_list,
 105                                 lqo_oss_list) {
 106                 if (oss->lqo_ost_count > temposs->lqo_ost_count)
 107                         break;
 108         }
 109         /* ...and add before it.  If we're the first or smallest, temposs
 110            points to the list head, and we add to the end. */
 111         cfs_list_add_tail(&oss->lqo_oss_list, &temposs->lqo_oss_list);
 112
 113         lov->lov_qos.lq_dirty = 1;
 114         lov->lov_qos.lq_rr.lqr_dirty = 1;
 115
 116         CDEBUG(D_QOS, "add tgt %s to OSS %s (%d OSTs)\n",
 117                obd_uuid2str(&lov->lov_tgts[index]->ltd_uuid),
 118                obd_uuid2str(&oss->lqo_uuid),
 119                oss->lqo_ost_count);
 120
 121 out:
 122         cfs_mutex_up(&lov->lov_lock);
 123         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 124         RETURN(rc);
 125 }
 126
 127 int qos_del_tgt(struct obd_device *obd, struct lov_tgt_desc *tgt)
 128 {
 129         struct lov_obd *lov = &obd->u.lov;
 130         struct lov_qos_oss *oss;
 131         int rc = 0;
 132         ENTRY;
 133
 134         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 135
 136         oss = tgt->ltd_qos.ltq_oss;
 137         if (!oss)
 138                 GOTO(out, rc = -ENOENT);
 139
 140         oss->lqo_ost_count--;
 141         if (oss->lqo_ost_count == 0) {
 142                 CDEBUG(D_QOS, "removing OSS %s\n",
 143                        obd_uuid2str(&oss->lqo_uuid));
 144                 cfs_list_del(&oss->lqo_oss_list);
 145                 OBD_FREE_PTR(oss);
 146         }
 147
 148         lov->lov_qos.lq_dirty = 1;
 149         lov->lov_qos.lq_rr.lqr_dirty = 1;
 150 out:
 151         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 152         RETURN(rc);
 153 }
 154
 155 /* Recalculate per-object penalties for OSSs and OSTs,
 156    depends on size of each ost in an oss */
 157 static int qos_calc_ppo(struct obd_device *obd)
 158 {
 159         struct lov_obd *lov = &obd->u.lov;
 160         struct lov_qos_oss *oss;
 161         __u64 ba_max, ba_min, temp;
 162         __u32 num_active;
 163         int rc, i, prio_wide;
 164         time_t now, age;
 165         ENTRY;
 166
 167         if (!lov->lov_qos.lq_dirty)
 168                 GOTO(out, rc = 0);
 169
 170         num_active = lov->desc.ld_active_tgt_count - 1;
 171         if (num_active < 1)
 172                 GOTO(out, rc = -EAGAIN);
 173
 174         /* find bavail on each OSS */
 175         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 176                 oss->lqo_bavail = 0;
 177         }
 178         lov->lov_qos.lq_active_oss_count = 0;
 179
 180         /* How badly user wants to select osts "widely" (not recently chosen
 181            and not on recent oss's).  As opposed to "freely" (free space
 182            avail.) 0-256. */
 183         prio_wide = 256 - lov->lov_qos.lq_prio_free;
 184
 185         ba_min = (__u64)(-1);
 186         ba_max = 0;
 187         now = cfs_time_current_sec();
 188         /* Calculate OST penalty per object */
 189         /* (lov ref taken in alloc_qos) */
 190         for (i = 0; i < lov->desc.ld_tgt_count; i++) {
 191                 if (!lov->lov_tgts[i] || !lov->lov_tgts[i]->ltd_active)
 192                         continue;
 193                 temp = TGT_BAVAIL(i);
 194                 if (!temp)
 195                         continue;
 196                 ba_min = min(temp, ba_min);
 197                 ba_max = max(temp, ba_max);
 198
 199                 /* Count the number of usable OSS's */
 200                 if (lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_bavail == 0)
 201                         lov->lov_qos.lq_active_oss_count++;
 202                 lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_bavail += temp;
 203
 204                 /* per-OST penalty is prio * TGT_bavail / (num_ost - 1) / 2 */
 205                 temp >>= 1;
 206                 do_div(temp, num_active);
 207                 lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj =
 208                         (temp * prio_wide) >> 8;
 209
 210                 age = (now - lov->lov_tgts[i]->ltd_qos.ltq_used) >> 3;
 211                 if (lov->lov_qos.lq_reset || age > 32 * lov->desc.ld_qos_maxage)
 212                         lov->lov_tgts[i]->ltd_qos.ltq_penalty = 0;
 213                 else if (age > lov->desc.ld_qos_maxage)
 214                         /* Decay the penalty by half for every 8x the update
 215                          * interval that the device has been idle.  That gives
 216                          * lots of time for the statfs information to be
 217                          * updated (which the penalty is only a proxy for),
 218                          * and avoids penalizing OSS/OSTs under light load. */
 219                         lov->lov_tgts[i]->ltd_qos.ltq_penalty >>=
 220                                 (age / lov->desc.ld_qos_maxage);
 221         }
 222
 223         num_active = lov->lov_qos.lq_active_oss_count - 1;
 224         if (num_active < 1) {
 225                 /* If there's only 1 OSS, we can't penalize it, so instead
 226                    we have to double the OST penalty */
 227                 num_active = 1;
 228                 for (i = 0; i < lov->desc.ld_tgt_count; i++) {
 229                         if (lov->lov_tgts[i] == NULL)
 230                                 continue;
 231                         lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj <<= 1;
 232                 }
 233         }
 234
 235         /* Per-OSS penalty is prio * oss_avail / oss_osts / (num_oss - 1) / 2 */
 236         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 237                 temp = oss->lqo_bavail >> 1;
 238                 do_div(temp, oss->lqo_ost_count * num_active);
 239                 oss->lqo_penalty_per_obj = (temp * prio_wide) >> 8;
 240
 241                 age = (now - oss->lqo_used) >> 3;
 242                 if (lov->lov_qos.lq_reset || age > 32 * lov->desc.ld_qos_maxage)
 243                         oss->lqo_penalty = 0;
 244                 else if (age > lov->desc.ld_qos_maxage)
 245                         /* Decay the penalty by half for every 8x the update
 246                          * interval that the device has been idle.  That gives
 247                          * lots of time for the statfs information to be
 248                          * updated (which the penalty is only a proxy for),
 249                          * and avoids penalizing OSS/OSTs under light load. */
 250                         oss->lqo_penalty >>= (age / lov->desc.ld_qos_maxage);
 251         }
 252
 253         lov->lov_qos.lq_dirty = 0;
 254         lov->lov_qos.lq_reset = 0;
 255
 256         /* If each ost has almost same free space,
 257          * do rr allocation for better creation performance */
 258         lov->lov_qos.lq_same_space = 0;
 259         if ((ba_max * (256 - lov->lov_qos.lq_threshold_rr)) >> 8 < ba_min) {
 260                 lov->lov_qos.lq_same_space = 1;
 261                 /* Reset weights for the next time we enter qos mode */
 262                 lov->lov_qos.lq_reset = 1;
 263         }
 264         rc = 0;
 265
 266 out:
 267         if (!rc && lov->lov_qos.lq_same_space)
 268                 RETURN(-EAGAIN);
 269         RETURN(rc);
 270 }
 271
 272 static int qos_calc_weight(struct lov_obd *lov, int i)
 273 {
 274         __u64 temp, temp2;
 275
 276         /* Final ost weight = TGT_BAVAIL - ost_penalty - oss_penalty */
 277         temp = TGT_BAVAIL(i);
 278         temp2 = lov->lov_tgts[i]->ltd_qos.ltq_penalty +
 279                 lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty;
 280         if (temp < temp2)
 281                 lov->lov_tgts[i]->ltd_qos.ltq_weight = 0;
 282         else
 283                 lov->lov_tgts[i]->ltd_qos.ltq_weight = temp - temp2;
 284         return 0;
 285 }
 286
 287 /* We just used this index for a stripe; adjust everyone's weights */
 288 static int qos_used(struct lov_obd *lov, struct ost_pool *osts,
 289                     __u32 index, __u64 *total_wt)
 290 {
 291         struct lov_qos_oss *oss;
 292         int j;
 293         ENTRY;
 294
 295         /* Don't allocate from this stripe anymore, until the next alloc_qos */
 296         lov->lov_tgts[index]->ltd_qos.ltq_usable = 0;
 297
 298         oss = lov->lov_tgts[index]->ltd_qos.ltq_oss;
 299
 300         /* Decay old penalty by half (we're adding max penalty, and don't
 301            want it to run away.) */
 302         lov->lov_tgts[index]->ltd_qos.ltq_penalty >>= 1;
 303         oss->lqo_penalty >>= 1;
 304
 305         /* mark the OSS and OST as recently used */
 306         lov->lov_tgts[index]->ltd_qos.ltq_used =
 307                 oss->lqo_used = cfs_time_current_sec();
 308
 309         /* Set max penalties for this OST and OSS */
 310         lov->lov_tgts[index]->ltd_qos.ltq_penalty +=
 311                 lov->lov_tgts[index]->ltd_qos.ltq_penalty_per_obj *
 312                 lov->desc.ld_active_tgt_count;
 313         oss->lqo_penalty += oss->lqo_penalty_per_obj *
 314                 lov->lov_qos.lq_active_oss_count;
 315
 316         /* Decrease all OSS penalties */
 317         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 318                 if (oss->lqo_penalty < oss->lqo_penalty_per_obj)
 319                         oss->lqo_penalty = 0;
 320                 else
 321                         oss->lqo_penalty -= oss->lqo_penalty_per_obj;
 322         }
 323
 324         *total_wt = 0;
 325         /* Decrease all OST penalties */
 326         for (j = 0; j < osts->op_count; j++) {
 327                 int i;
 328
 329                 i = osts->op_array[j];
 330                 if (!lov->lov_tgts[i] || !lov->lov_tgts[i]->ltd_active)
 331                         continue;
 332                 if (lov->lov_tgts[i]->ltd_qos.ltq_penalty <
 333                     lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj)
 334                         lov->lov_tgts[i]->ltd_qos.ltq_penalty = 0;
 335                 else
 336                         lov->lov_tgts[i]->ltd_qos.ltq_penalty -=
 337                         lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj;
 338
 339                 qos_calc_weight(lov, i);
 340
 341                 /* Recalc the total weight of usable osts */
 342                 if (lov->lov_tgts[i]->ltd_qos.ltq_usable)
 343                         *total_wt += lov->lov_tgts[i]->ltd_qos.ltq_weight;
 344
 345 #ifdef QOS_DEBUG
 346                 CDEBUG(D_QOS, "recalc tgt %d usable=%d avail="LPU64
 347                        " ostppo="LPU64" ostp="LPU64" ossppo="LPU64
 348                        " ossp="LPU64" wt="LPU64"\n",
 349                        i, lov->lov_tgts[i]->ltd_qos.ltq_usable,
 350                        TGT_BAVAIL(i) >> 10,
 351                        lov->lov_tgts[i]->ltd_qos.ltq_penalty_per_obj >> 10,
 352                        lov->lov_tgts[i]->ltd_qos.ltq_penalty >> 10,
 353                        lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty_per_obj>>10,
 354                        lov->lov_tgts[i]->ltd_qos.ltq_oss->lqo_penalty >> 10,
 355                        lov->lov_tgts[i]->ltd_qos.ltq_weight >> 10);
 356 #endif
 357         }
 358
 359         RETURN(0);
 360 }
 361
 362 #define LOV_QOS_EMPTY ((__u32)-1)
 363 /* compute optimal round-robin order, based on OSTs per OSS */
 364 static int qos_calc_rr(struct lov_obd *lov, struct ost_pool *src_pool,
 365                        struct lov_qos_rr *lqr)
 366 {
 367         struct lov_qos_oss *oss;
 368         unsigned placed, real_count;
 369         int i, rc;
 370         ENTRY;
 371
 372         if (!lqr->lqr_dirty) {
 373                 LASSERT(lqr->lqr_pool.op_size);
 374                 RETURN(0);
 375         }
 376
 377         /* Do actual allocation. */
 378         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 379
 380         /*
 381          * Check again. While we were sleeping on @lq_rw_sem something could
 382          * change.
 383          */
 384         if (!lqr->lqr_dirty) {
 385                 LASSERT(lqr->lqr_pool.op_size);
 386                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
 387                 RETURN(0);
 388         }
 389
 390         real_count = src_pool->op_count;
 391
 392         /* Zero the pool array */
 393         /* alloc_rr is holding a read lock on the pool, so nobody is adding/
 394            deleting from the pool. The lq_rw_sem insures that nobody else
 395            is reading. */
 396         lqr->lqr_pool.op_count = real_count;
 397         rc = lov_ost_pool_extend(&lqr->lqr_pool, real_count);
 398         if (rc) {
 399                 cfs_up_write(&lov->lov_qos.lq_rw_sem);
 400                 RETURN(rc);
 401         }
 402         for (i = 0; i < lqr->lqr_pool.op_count; i++)
 403                 lqr->lqr_pool.op_array[i] = LOV_QOS_EMPTY;
 404
 405         /* Place all the OSTs from 1 OSS at the same time. */
 406         placed = 0;
 407         cfs_list_for_each_entry(oss, &lov->lov_qos.lq_oss_list, lqo_oss_list) {
 408                 int j = 0;
 409                 for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 410                         if (lov->lov_tgts[src_pool->op_array[i]] &&
 411                             (lov->lov_tgts[src_pool->op_array[i]]->ltd_qos.ltq_oss == oss)) {
 412                               /* Evenly space these OSTs across arrayspace */
 413                               int next = j * lqr->lqr_pool.op_count / oss->lqo_ost_count;
 414                               while (lqr->lqr_pool.op_array[next] !=
 415                                      LOV_QOS_EMPTY)
 416                                         next = (next + 1) % lqr->lqr_pool.op_count;
 417                               lqr->lqr_pool.op_array[next] = src_pool->op_array[i];
 418                               j++;
 419                               placed++;
 420                         }
 421                 }
 422         }
 423
 424         lqr->lqr_dirty = 0;
 425         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 426
 427         if (placed != real_count) {
 428                 /* This should never happen */
 429                 LCONSOLE_ERROR_MSG(0x14e, "Failed to place all OSTs in the "
 430                                    "round-robin list (%d of %d).\n",
 431                                    placed, real_count);
 432                 for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 433                         LCONSOLE(D_WARNING, "rr #%d ost idx=%d\n", i,
 434                                  lqr->lqr_pool.op_array[i]);
 435                 }
 436                 lqr->lqr_dirty = 1;
 437                 RETURN(-EAGAIN);
 438         }
 439
 440 #ifdef QOS_DEBUG
 441         for (i = 0; i < lqr->lqr_pool.op_count; i++) {
 442                 LCONSOLE(D_QOS, "rr #%d ost idx=%d\n", i,
 443                          lqr->lqr_pool.op_array[i]);
 444         }
 445 #endif
 446
 447         RETURN(0);
 448 }
 449
 450
 451 void qos_shrink_lsm(struct lov_request_set *set)
 452 {
 453         struct lov_stripe_md *lsm = set->set_oi->oi_md, *lsm_new;
 454         /* XXX LOV STACKING call into osc for sizes */
 455         unsigned oldsize, newsize;
 456
 457         if (set->set_oti && set->set_cookies && set->set_cookie_sent) {
 458                 struct llog_cookie *cookies;
 459                 oldsize = lsm->lsm_stripe_count * sizeof(*cookies);
 460                 newsize = set->set_count * sizeof(*cookies);
 461
 462                 cookies = set->set_cookies;
 463                 oti_alloc_cookies(set->set_oti, set->set_count);
 464                 if (set->set_oti->oti_logcookies) {
 465                         memcpy(set->set_oti->oti_logcookies, cookies, newsize);
 466                         OBD_FREE_LARGE(cookies, oldsize);
 467                         set->set_cookies = set->set_oti->oti_logcookies;
 468                 } else {
 469                         CWARN("'leaking' %d bytes\n", oldsize - newsize);
 470                 }
 471         }
 472
 473         CWARN("using fewer stripes for object "LPU64": old %u new %u\n",
 474               lsm->lsm_object_id, lsm->lsm_stripe_count, set->set_count);
 475         LASSERT(lsm->lsm_stripe_count >= set->set_count);
 476
 477         newsize = lov_stripe_md_size(set->set_count);
 478         OBD_ALLOC_LARGE(lsm_new, newsize);
 479         if (lsm_new != NULL) {
 480                 int i;
 481                 memcpy(lsm_new, lsm, sizeof(*lsm));
 482                 for (i = 0; i < lsm->lsm_stripe_count; i++) {
 483                         if (i < set->set_count) {
 484                                 lsm_new->lsm_oinfo[i] = lsm->lsm_oinfo[i];
 485                                 continue;
 486                         }
 487                         OBD_SLAB_FREE(lsm->lsm_oinfo[i], lov_oinfo_slab,
 488                                       sizeof(struct lov_oinfo));
 489                 }
 490                 lsm_new->lsm_stripe_count = set->set_count;
 491                 OBD_FREE_LARGE(lsm, sizeof(struct lov_stripe_md) +
 492                                lsm->lsm_stripe_count*sizeof(struct lov_oinfo*));
 493                 set->set_oi->oi_md = lsm_new;
 494         } else {
 495                 CWARN("'leaking' few bytes\n");
 496         }
 497 }
 498
 499 /**
 500  * Check whether we can create the object on the OST(refered by ost_idx)
 501  * \retval:
 502  *          0: create the object.
 503  *          other value: did not create the object.
 504  */
 505 static int lov_check_and_create_object(struct lov_obd *lov, int ost_idx,
 506                                        struct lov_stripe_md *lsm,
 507                                        struct lov_request *req,
 508                                        struct obd_trans_info *oti)
 509 {
 510         __u16 stripe;
 511         int rc = -EIO;
 512         ENTRY;
 513
 514         CDEBUG(D_QOS, "Check and create on idx %d \n", ost_idx);
 515         if (!lov->lov_tgts[ost_idx] ||
 516             !lov->lov_tgts[ost_idx]->ltd_active)
 517                 RETURN(rc);
 518
 519         /* check if objects has been created on this ost */
 520         for (stripe = 0; stripe < lsm->lsm_stripe_count; stripe++) {
 521                 /* already have object at this stripe */
 522                 if (ost_idx == lsm->lsm_oinfo[stripe]->loi_ost_idx)
 523                         break;
 524         }
 525
 526         if (stripe >= lsm->lsm_stripe_count) {
 527                 req->rq_idx = ost_idx;
 528                 rc = obd_create(lov->lov_tgts[ost_idx]->ltd_exp,
 529                                 req->rq_oi.oi_oa, &req->rq_oi.oi_md,
 530                                 oti);
 531         }
 532         RETURN(rc);
 533 }
 534
 535 int qos_remedy_create(struct lov_request_set *set, struct lov_request *req)
 536 {
 537         struct lov_stripe_md *lsm = set->set_oi->oi_md;
 538         struct lov_obd *lov = &set->set_exp->exp_obd->u.lov;
 539         unsigned ost_idx = 0, ost_count;
 540         struct pool_desc *pool;
 541         struct ost_pool *osts = NULL;
 542         int i, rc = -EIO;
 543         ENTRY;
 544
 545         /* First check whether we can create the objects on the pool */
 546         pool = lov_find_pool(lov, lsm->lsm_pool_name);
 547         if (pool != NULL) {
 548                 cfs_down_read(&pool_tgt_rw_sem(pool));
 549                 osts = &(pool->pool_obds);
 550                 ost_count = osts->op_count;
 551                 for (i = 0; i < ost_count; i++, ost_idx = osts->op_array[i]) {
 552                         rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 553                                                          set->set_oti);
 554                         if (rc == 0)
 555                                 break;
 556                 }
 557                 cfs_up_read(&pool_tgt_rw_sem(pool));
 558                 lov_pool_putref(pool);
 559                 RETURN(rc);
 560         }
 561
 562         ost_count = lov->desc.ld_tgt_count;
 563         /* Then check whether we can create the objects on other OSTs */
 564         ost_idx = (req->rq_idx + lsm->lsm_stripe_count) % ost_count;
 565         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
 566                 rc = lov_check_and_create_object(lov, ost_idx, lsm, req,
 567                                                  set->set_oti);
 568
 569                 if (rc == 0)
 570                         break;
 571         }
 572
 573         RETURN(rc);
 574 }
 575
 576 static int min_stripe_count(int stripe_cnt, int flags)
 577 {
 578         return (flags & LOV_USES_DEFAULT_STRIPE ?
 579                 stripe_cnt - (stripe_cnt / 4) : stripe_cnt);
 580 }
 581
 582 #define LOV_CREATE_RESEED_MULT 30
 583 #define LOV_CREATE_RESEED_MIN  2000
 584 /* Allocate objects on osts with round-robin algorithm */
 585 static int alloc_rr(struct lov_obd *lov, int *idx_arr, int *stripe_cnt,
 586                     char *poolname, int flags)
 587 {
 588         unsigned array_idx;
 589         int i, rc, *idx_pos;
 590         __u32 ost_idx;
 591         int ost_start_idx_temp;
 592         int speed = 0;
 593         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 594         struct pool_desc *pool;
 595         struct ost_pool *osts;
 596         struct lov_qos_rr *lqr;
 597         ENTRY;
 598
 599         pool = lov_find_pool(lov, poolname);
 600         if (pool == NULL) {
 601                 osts = &(lov->lov_packed);
 602                 lqr = &(lov->lov_qos.lq_rr);
 603         } else {
 604                 cfs_down_read(&pool_tgt_rw_sem(pool));
 605                 osts = &(pool->pool_obds);
 606                 lqr = &(pool->pool_rr);
 607         }
 608
 609         rc = qos_calc_rr(lov, osts, lqr);
 610         if (rc)
 611                 GOTO(out, rc);
 612
 613         if (--lqr->lqr_start_count <= 0) {
 614                 lqr->lqr_start_idx = cfs_rand() % osts->op_count;
 615                 lqr->lqr_start_count =
 616                         (LOV_CREATE_RESEED_MIN / max(osts->op_count, 1U) +
 617                          LOV_CREATE_RESEED_MULT) * max(osts->op_count, 1U);
 618         } else if (stripe_cnt_min >= osts->op_count ||
 619                    lqr->lqr_start_idx > osts->op_count) {
 620                 /* If we have allocated from all of the OSTs, slowly
 621                  * precess the next start if the OST/stripe count isn't
 622                  * already doing this for us. */
 623                 lqr->lqr_start_idx %= osts->op_count;
 624                 if (*stripe_cnt > 1 && (osts->op_count % (*stripe_cnt)) != 1)
 625                         ++lqr->lqr_offset_idx;
 626         }
 627         cfs_down_read(&lov->lov_qos.lq_rw_sem);
 628         ost_start_idx_temp = lqr->lqr_start_idx;
 629
 630 repeat_find:
 631         array_idx = (lqr->lqr_start_idx + lqr->lqr_offset_idx) % osts->op_count;
 632         idx_pos = idx_arr;
 633 #ifdef QOS_DEBUG
 634         CDEBUG(D_QOS, "pool '%s' want %d startidx %d startcnt %d offset %d "
 635                "active %d count %d arrayidx %d\n", poolname,
 636                *stripe_cnt, lqr->lqr_start_idx, lqr->lqr_start_count,
 637                lqr->lqr_offset_idx, osts->op_count, osts->op_count, array_idx);
 638 #endif
 639
 640         for (i = 0; i < osts->op_count;
 641                     i++, array_idx=(array_idx + 1) % osts->op_count) {
 642                 ++lqr->lqr_start_idx;
 643                 ost_idx = lqr->lqr_pool.op_array[array_idx];
 644 #ifdef QOS_DEBUG
 645                 CDEBUG(D_QOS, "#%d strt %d act %d strp %d ary %d idx %d\n",
 646                        i, lqr->lqr_start_idx,
 647                        ((ost_idx != LOV_QOS_EMPTY) && lov->lov_tgts[ost_idx]) ?
 648                        lov->lov_tgts[ost_idx]->ltd_active : 0,
 649                        idx_pos - idx_arr, array_idx, ost_idx);
 650 #endif
 651                 if ((ost_idx == LOV_QOS_EMPTY) || !lov->lov_tgts[ost_idx] ||
 652                     !lov->lov_tgts[ost_idx]->ltd_active)
 653                         continue;
 654
 655                 /* Fail Check before osc_precreate() is called
 656                    so we can only 'fail' single OSC. */
 657                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 658                         continue;
 659
 660                 /* Drop slow OSCs if we can */
 661                 if (obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed)
 662                         continue;
 663
 664                 *idx_pos = ost_idx;
 665                 idx_pos++;
 666                 /* We have enough stripes */
 667                 if (idx_pos - idx_arr == *stripe_cnt)
 668                         break;
 669         }
 670         if ((speed < 2) && (idx_pos - idx_arr < stripe_cnt_min)) {
 671                 /* Try again, allowing slower OSCs */
 672                 speed++;
 673                 lqr->lqr_start_idx = ost_start_idx_temp;
 674                 goto repeat_find;
 675         }
 676
 677         cfs_up_read(&lov->lov_qos.lq_rw_sem);
 678
 679         *stripe_cnt = idx_pos - idx_arr;
 680 out:
 681         if (pool != NULL) {
 682                 cfs_up_read(&pool_tgt_rw_sem(pool));
 683                 /* put back ref got by lov_find_pool() */
 684                 lov_pool_putref(pool);
 685         }
 686
 687         RETURN(rc);
 688 }
 689
 690 /* alloc objects on osts with specific stripe offset */
 691 static int alloc_specific(struct lov_obd *lov, struct lov_stripe_md *lsm,
 692                           int *idx_arr)
 693 {
 694         unsigned ost_idx, array_idx, ost_count;
 695         int i, rc, *idx_pos;
 696         int speed = 0;
 697         struct pool_desc *pool;
 698         struct ost_pool *osts;
 699         ENTRY;
 700
 701         pool = lov_find_pool(lov, lsm->lsm_pool_name);
 702         if (pool == NULL) {
 703                 osts = &(lov->lov_packed);
 704         } else {
 705                 cfs_down_read(&pool_tgt_rw_sem(pool));
 706                 osts = &(pool->pool_obds);
 707         }
 708
 709         ost_count = osts->op_count;
 710
 711 repeat_find:
 712         /* search loi_ost_idx in ost array */
 713         array_idx = 0;
 714         for (i = 0; i < ost_count; i++) {
 715                 if (osts->op_array[i] == lsm->lsm_oinfo[0]->loi_ost_idx) {
 716                         array_idx = i;
 717                         break;
 718                 }
 719         }
 720         if (i == ost_count) {
 721                 CERROR("Start index %d not found in pool '%s'\n",
 722                        lsm->lsm_oinfo[0]->loi_ost_idx, lsm->lsm_pool_name);
 723                 GOTO(out, rc = -EINVAL);
 724         }
 725
 726         idx_pos = idx_arr;
 727         for (i = 0; i < ost_count;
 728              i++, array_idx = (array_idx + 1) % ost_count) {
 729                 ost_idx = osts->op_array[array_idx];
 730
 731                 if (!lov->lov_tgts[ost_idx] ||
 732                     !lov->lov_tgts[ost_idx]->ltd_active) {
 733                         continue;
 734                 }
 735
 736                 /* Fail Check before osc_precreate() is called
 737                    so we can only 'fail' single OSC. */
 738                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0)
 739                         continue;
 740
 741                 /* Drop slow OSCs if we can, but not for requested start idx.
 742                  *
 743                  * This means "if OSC is slow and it is not the requested
 744                  * start OST, then it can be skipped, otherwise skip it only
 745                  * if it is inactive/recovering/out-of-space." */
 746                 if ((obd_precreate(lov->lov_tgts[ost_idx]->ltd_exp) > speed) &&
 747                     (i != 0 || speed >= 2))
 748                         continue;
 749
 750                 *idx_pos = ost_idx;
 751                 idx_pos++;
 752                 /* We have enough stripes */
 753                 if (idx_pos - idx_arr == lsm->lsm_stripe_count)
 754                         GOTO(out, rc = 0);
 755         }
 756         if (speed < 2) {
 757                 /* Try again, allowing slower OSCs */
 758                 speed++;
 759                 goto repeat_find;
 760         }
 761
 762         /* If we were passed specific striping params, then a failure to
 763          * meet those requirements is an error, since we can't reallocate
 764          * that memory (it might be part of a larger array or something).
 765          *
 766          * We can only get here if lsm_stripe_count was originally > 1.
 767          */
 768         CERROR("can't lstripe objid "LPX64": have %d want %u\n",
 769                lsm->lsm_object_id, (int)(idx_pos - idx_arr),
 770                lsm->lsm_stripe_count);
 771         rc = -EFBIG;
 772 out:
 773         if (pool != NULL) {
 774                 cfs_up_read(&pool_tgt_rw_sem(pool));
 775                 /* put back ref got by lov_find_pool() */
 776                 lov_pool_putref(pool);
 777         }
 778
 779         RETURN(rc);
 780 }
 781
 782 /* Alloc objects on osts with optimization based on:
 783    - free space
 784    - network resources (shared OSS's)
 785 */
 786 static int alloc_qos(struct obd_export *exp, int *idx_arr, int *stripe_cnt,
 787                      char *poolname, int flags)
 788 {
 789         struct lov_obd *lov = &exp->exp_obd->u.lov;
 790         __u64 total_weight = 0;
 791         int nfound, good_osts, i, rc = 0;
 792         int stripe_cnt_min = min_stripe_count(*stripe_cnt, flags);
 793         struct pool_desc *pool;
 794         struct ost_pool *osts;
 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         } else {
 804                 cfs_down_read(&pool_tgt_rw_sem(pool));
 805                 osts = &(pool->pool_obds);
 806         }
 807
 808         obd_getref(exp->exp_obd);
 809
 810         /* wait for fresh statfs info if needed, the rpcs are sent in
 811          * lov_create() */
 812         qos_statfs_update(exp->exp_obd,
 813                           cfs_time_shift_64(-2 * lov->desc.ld_qos_maxage), 1);
 814
 815         /* Detect -EAGAIN early, before expensive lock is taken. */
 816         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 817                 GOTO(out_nolock, rc = -EAGAIN);
 818
 819         /* Do actual allocation, use write lock here. */
 820         cfs_down_write(&lov->lov_qos.lq_rw_sem);
 821
 822         /*
 823          * Check again, while we were sleeping on @lq_rw_sem things could
 824          * change.
 825          */
 826         if (!lov->lov_qos.lq_dirty && lov->lov_qos.lq_same_space)
 827                 GOTO(out, rc = -EAGAIN);
 828
 829         if (lov->desc.ld_active_tgt_count < 2)
 830                 GOTO(out, rc = -EAGAIN);
 831
 832         rc = qos_calc_ppo(exp->exp_obd);
 833         if (rc)
 834                 GOTO(out, rc);
 835
 836         good_osts = 0;
 837         /* Find all the OSTs that are valid stripe candidates */
 838         for (i = 0; i < osts->op_count; i++) {
 839                 if (!lov->lov_tgts[osts->op_array[i]] ||
 840                     !lov->lov_tgts[osts->op_array[i]]->ltd_active)
 841                         continue;
 842
 843                 /* Fail Check before osc_precreate() is called
 844                    so we can only 'fail' single OSC. */
 845                 if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && osts->op_array[i] == 0)
 846                         continue;
 847
 848                 if (obd_precreate(lov->lov_tgts[osts->op_array[i]]->ltd_exp) > 2)
 849                         continue;
 850
 851                 lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable = 1;
 852                 qos_calc_weight(lov, osts->op_array[i]);
 853                 total_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 854
 855                 good_osts++;
 856         }
 857
 858 #ifdef QOS_DEBUG
 859         CDEBUG(D_QOS, "found %d good osts\n", good_osts);
 860 #endif
 861
 862         if (good_osts < stripe_cnt_min)
 863                 GOTO(out, rc = -EAGAIN);
 864
 865         /* We have enough osts */
 866         if (good_osts < *stripe_cnt)
 867                 *stripe_cnt = good_osts;
 868
 869         if (!*stripe_cnt)
 870                 GOTO(out, rc = -EAGAIN);
 871
 872         /* Find enough OSTs with weighted random allocation. */
 873         nfound = 0;
 874         while (nfound < *stripe_cnt) {
 875                 __u64 rand, cur_weight;
 876
 877                 cur_weight = 0;
 878                 rc = -ENODEV;
 879
 880                 if (total_weight) {
 881 #if BITS_PER_LONG == 32
 882                         rand = cfs_rand() % (unsigned)total_weight;
 883                         /* If total_weight > 32-bit, first generate the high
 884                          * 32 bits of the random number, then add in the low
 885                          * 32 bits (truncated to the upper limit, if needed) */
 886                         if (total_weight > 0xffffffffULL)
 887                                 rand = (__u64)(cfs_rand() %
 888                                           (unsigned)(total_weight >> 32)) << 32;
 889                         else
 890                                 rand = 0;
 891
 892                         if (rand == (total_weight & 0xffffffff00000000ULL))
 893                                 rand |= cfs_rand() % (unsigned)total_weight;
 894                         else
 895                                 rand |= cfs_rand();
 896
 897 #else
 898                         rand = ((__u64)cfs_rand() << 32 | cfs_rand()) %
 899                                 total_weight;
 900 #endif
 901                 } else {
 902                         rand = 0;
 903                 }
 904
 905                 /* On average, this will hit larger-weighted osts more often.
 906                    0-weight osts will always get used last (only when rand=0).*/
 907                 for (i = 0; i < osts->op_count; i++) {
 908                         if (!lov->lov_tgts[osts->op_array[i]] ||
 909                             !lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_usable)
 910                                 continue;
 911
 912                         cur_weight += lov->lov_tgts[osts->op_array[i]]->ltd_qos.ltq_weight;
 913 #ifdef QOS_DEBUG
 914                         CDEBUG(D_QOS, "stripe_cnt=%d nfound=%d cur_weight="LPU64
 915                                       " rand="LPU64" total_weight="LPU64"\n",
 916                                *stripe_cnt, nfound, cur_weight, rand, total_weight);
 917 #endif
 918                         if (cur_weight >= rand) {
 919 #ifdef QOS_DEBUG
 920                                 CDEBUG(D_QOS, "assigned stripe=%d to idx=%d\n",
 921                                        nfound, osts->op_array[i]);
 922 #endif
 923                                 idx_arr[nfound++] = osts->op_array[i];
 924                                 qos_used(lov, osts, osts->op_array[i], &total_weight);
 925                                 rc = 0;
 926                                 break;
 927                         }
 928                 }
 929                 /* should never satisfy below condition */
 930                 if (rc) {
 931                         CERROR("Didn't find any OSTs?\n");
 932                         break;
 933                 }
 934         }
 935         LASSERT(nfound == *stripe_cnt);
 936
 937 out:
 938         cfs_up_write(&lov->lov_qos.lq_rw_sem);
 939
 940 out_nolock:
 941         if (pool != NULL) {
 942                 cfs_up_read(&pool_tgt_rw_sem(pool));
 943                 /* put back ref got by lov_find_pool() */
 944                 lov_pool_putref(pool);
 945         }
 946
 947         if (rc == -EAGAIN)
 948                 rc = alloc_rr(lov, idx_arr, stripe_cnt, poolname, flags);
 949
 950         obd_putref(exp->exp_obd);
 951         RETURN(rc);
 952 }
 953
 954 /* return new alloced stripe count on success */
 955 static int alloc_idx_array(struct obd_export *exp, struct lov_stripe_md *lsm,
 956                            int newea, int **idx_arr, int *arr_cnt, int flags)
 957 {
 958         struct lov_obd *lov = &exp->exp_obd->u.lov;
 959         int stripe_cnt = lsm->lsm_stripe_count;
 960         int i, rc = 0;
 961         int *tmp_arr = NULL;
 962         ENTRY;
 963
 964         *arr_cnt = stripe_cnt;
 965         OBD_ALLOC(tmp_arr, *arr_cnt * sizeof(int));
 966         if (tmp_arr == NULL)
 967                 RETURN(-ENOMEM);
 968         for (i = 0; i < *arr_cnt; i++)
 969                 tmp_arr[i] = -1;
 970
 971         if (newea ||
 972             lsm->lsm_oinfo[0]->loi_ost_idx >= lov->desc.ld_tgt_count)
 973                 rc = alloc_qos(exp, tmp_arr, &stripe_cnt,
 974                                lsm->lsm_pool_name, flags);
 975         else
 976                 rc = alloc_specific(lov, lsm, tmp_arr);
 977
 978         if (rc)
 979                 GOTO(out_arr, rc);
 980
 981         *idx_arr = tmp_arr;
 982         RETURN(stripe_cnt);
 983 out_arr:
 984         OBD_FREE(tmp_arr, *arr_cnt * sizeof(int));
 985         *arr_cnt = 0;
 986         RETURN(rc);
 987 }
 988
 989 static void free_idx_array(int *idx_arr, int arr_cnt)
 990 {
 991         if (arr_cnt)
 992                 OBD_FREE(idx_arr, arr_cnt * sizeof(int));
 993 }
 994
 995 int qos_prep_create(struct obd_export *exp, struct lov_request_set *set)
 996 {
 997         struct lov_obd *lov = &exp->exp_obd->u.lov;
 998         struct lov_stripe_md *lsm;
 999         struct obdo *src_oa = set->set_oi->oi_oa;
1000         struct obd_trans_info *oti = set->set_oti;
1001         int i, stripes, rc = 0, newea = 0;
1002         int flag = LOV_USES_ASSIGNED_STRIPE;
1003         int *idx_arr = NULL, idx_cnt = 0;
1004         ENTRY;
1005
1006         LASSERT(src_oa->o_valid & OBD_MD_FLID);
1007         LASSERT(src_oa->o_valid & OBD_MD_FLGROUP);
1008
1009         if (set->set_oi->oi_md == NULL) {
1010                 __u16 stripes_def = lov_get_stripecnt(lov, LOV_MAGIC, 0);
1011
1012                 /* If the MDS file was truncated up to some size, stripe over
1013                  * enough OSTs to allow the file to be created at that size.
1014                  * This may mean we use more than the default # of stripes. */
1015                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
1016                         obd_size min_bavail = LUSTRE_STRIPE_MAXBYTES;
1017
1018                         /* Find a small number of stripes we can use
1019                            (up to # of active osts). */
1020                         stripes = 1;
1021                         for (i = 0; i < lov->desc.ld_tgt_count; i++) {
1022                                 if (!lov->lov_tgts[i] ||
1023                                     !lov->lov_tgts[i]->ltd_active)
1024                                         continue;
1025                                 min_bavail = min(min_bavail, TGT_BAVAIL(i));
1026                                 if (min_bavail * stripes > src_oa->o_size)
1027                                         break;
1028                                 stripes++;
1029                         }
1030
1031                         if (stripes < stripes_def)
1032                                 stripes = stripes_def;
1033                 } else {
1034                         flag = LOV_USES_DEFAULT_STRIPE;
1035                         stripes = stripes_def;
1036                 }
1037
1038                 rc = lov_alloc_memmd(&set->set_oi->oi_md, stripes,
1039                                      lov->desc.ld_pattern ?
1040                                      lov->desc.ld_pattern : LOV_PATTERN_RAID0,
1041                                      LOV_MAGIC);
1042                 if (rc < 0)
1043                         GOTO(out_err, rc);
1044                 newea = 1;
1045                 rc = 0;
1046         }
1047
1048         lsm = set->set_oi->oi_md;
1049         lsm->lsm_object_id = src_oa->o_id;
1050         lsm->lsm_object_seq = src_oa->o_seq;
1051         lsm->lsm_layout_gen = 0; /* actual generation set in mdd_lov_create() */
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_LARGE(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         cfs_down_write(&lov->lov_qos.lq_rw_sem);
1136         if (lov->lov_qos.lq_statfs_in_progress) {
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         }
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 }