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  * Copyright (C) 2002, 2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of the Lustre file system, http://www.lustre.org
   7  *   Lustre is a trademark of Cluster File Systems, Inc.
   8  *
   9  *   You may have signed or agreed to another license before downloading
  10  *   this software.  If so, you are bound by the terms and conditions
  11  *   of that agreement, and the following does not apply to you.  See the
  12  *   LICENSE file included with this distribution for more information.
  13  *
  14  *   If you did not agree to a different license, then this copy of Lustre
  15  *   is open source software; you can redistribute it and/or modify it
  16  *   under the terms of version 2 of the GNU General Public License as
  17  *   published by the Free Software Foundation.
  18  *
  19  *   In either case, Lustre is distributed in the hope that it will be
  20  *   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  21  *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  *   license text for more details.
  23  */
  24
  25 #ifndef EXPORT_SYMTAB
  26 # define EXPORT_SYMTAB
  27 #endif
  28 #define DEBUG_SUBSYSTEM S_LOV
  29
  30 #ifdef __KERNEL__
  31 #else
  32 #include <liblustre.h>
  33 #endif
  34
  35 #include <linux/obd_class.h>
  36 #include <linux/obd_lov.h>
  37
  38 #include "lov_internal.h"
  39
  40 void qos_shrink_lsm(struct lov_request_set *set)
  41 {
  42         struct lov_stripe_md *lsm = set->set_md, *lsm_new;
  43         /* XXX LOV STACKING call into osc for sizes */
  44         unsigned oldsize, newsize;
  45
  46         if (set->set_oti && set->set_cookies && set->set_cookie_sent) {
  47                 struct llog_cookie *cookies;
  48                 oldsize = lsm->lsm_stripe_count * sizeof(*cookies);
  49                 newsize = set->set_count * sizeof(*cookies);
  50
  51                 cookies = set->set_cookies;
  52                 oti_alloc_cookies(set->set_oti, set->set_count);
  53                 if (set->set_oti->oti_logcookies) {
  54                         memcpy(set->set_oti->oti_logcookies, cookies, newsize);
  55                         OBD_FREE(cookies, oldsize);
  56                         set->set_cookies = set->set_oti->oti_logcookies;
  57                 } else {
  58                         CWARN("'leaking' %d bytes\n", oldsize - newsize);
  59                 }
  60         }
  61
  62         CWARN("using fewer stripes for object "LPX64": old %u new %u\n",
  63               lsm->lsm_object_id, lsm->lsm_stripe_count, set->set_count);
  64
  65         oldsize = lov_stripe_md_size(lsm->lsm_stripe_count);
  66         newsize = lov_stripe_md_size(set->set_count);
  67         OBD_ALLOC(lsm_new, newsize);
  68         if (lsm_new != NULL) {
  69                 memcpy(lsm_new, lsm, newsize);
  70                 lsm_new->lsm_stripe_count = set->set_count;
  71                 OBD_FREE(lsm, oldsize);
  72                 set->set_md = lsm_new;
  73         } else {
  74                 CWARN("'leaking' %d bytes\n", oldsize - newsize);
  75         }
  76 }
  77
  78 int qos_remedy_create(struct lov_request_set *set, struct lov_request *req)
  79 {
  80         struct lov_stripe_md *lsm = set->set_md;
  81         struct lov_obd *lov = &set->set_exp->exp_obd->u.lov;
  82         unsigned ost_idx, ost_count = lov->desc.ld_tgt_count;
  83         int stripe, i, rc = -EIO;
  84         ENTRY;
  85
  86         ost_idx = (req->rq_idx + 1) % ost_count;
  87         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
  88                 if (lov->tgts[ost_idx].active == 0) {
  89                         CDEBUG(D_HA, "lov idx %d inactive\n", ost_idx);
  90                         continue;
  91                 }
  92                 /* check if objects has been created on this ost */
  93                 for (stripe = req->rq_stripe; stripe >= 0; stripe--) {
  94                         if (ost_idx == lsm->lsm_oinfo[stripe].loi_ost_idx)
  95                                 break;
  96                 }
  97
  98                 if (stripe < 0) {
  99                         req->rq_idx = ost_idx;
 100                         rc = obd_create(lov->tgts[ost_idx].ltd_exp, req->rq_oa,
 101                                         &req->rq_md, set->set_oti);
 102                         if (!rc)
 103                                 break;
 104                 }
 105         }
 106         RETURN(rc);
 107 }
 108
 109 #define LOV_CREATE_RESEED_MULT 4
 110 #define LOV_CREATE_RESEED_MIN  1000
 111 /* FIXME use real qos data to prepare the lov create request */
 112 int qos_prep_create(struct lov_obd *lov, struct lov_request_set *set, int newea)
 113 {
 114         static int ost_start_idx, ost_start_count;
 115         unsigned ost_idx, ost_count = lov->desc.ld_tgt_count;
 116         unsigned ost_active_count = lov->desc.ld_active_tgt_count;
 117         struct lov_stripe_md *lsm = set->set_md;
 118         struct obdo *src_oa = set->set_oa;
 119         int i, rc = 0;
 120         ENTRY;
 121
 122         LASSERT(src_oa->o_valid & OBD_MD_FLID);
 123
 124         lsm->lsm_object_id = src_oa->o_id;
 125         if (!lsm->lsm_stripe_size)
 126                 lsm->lsm_stripe_size = lov->desc.ld_default_stripe_size;
 127         if (!lsm->lsm_pattern) {
 128                 lsm->lsm_pattern = lov->desc.ld_pattern ?
 129                         lov->desc.ld_pattern : LOV_PATTERN_RAID0;
 130         }
 131
 132         if (newea || lsm->lsm_oinfo[0].loi_ost_idx >= ost_count) {
 133                 if (--ost_start_count <= 0) {
 134                         ost_start_idx = ll_insecure_random_int();
 135                         ost_start_count =
 136                           (LOV_CREATE_RESEED_MIN / max(ost_active_count, 1U) +
 137                            LOV_CREATE_RESEED_MULT) * max(ost_active_count, 1U);
 138                 } else if (lsm->lsm_stripe_count >= ost_active_count) {
 139                         /* If we allocate from all of the stripes, make the
 140                          * next file start on the next OST. */
 141                         ++ost_start_idx;
 142                 }
 143                 ost_idx = ost_start_idx % ost_count;
 144         } else {
 145                 ost_idx = lsm->lsm_oinfo[0].loi_ost_idx;
 146         }
 147
 148         CDEBUG(D_INODE, "allocating %d subobjs for objid "LPX64" at idx %d\n",
 149                lsm->lsm_stripe_count, lsm->lsm_object_id, ost_idx);
 150
 151         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
 152                 struct lov_request *req;
 153
 154                 ++ost_start_idx;
 155                 if (lov->tgts[ost_idx].active == 0) {
 156                         CDEBUG(D_HA, "lov idx %d inactive\n", ost_idx);
 157                         continue;
 158                 }
 159
 160                 OBD_ALLOC(req, sizeof(*req));
 161                 if (req == NULL)
 162                         GOTO(out, rc = -ENOMEM);
 163
 164                 req->rq_buflen = sizeof(*req->rq_md);
 165                 OBD_ALLOC(req->rq_md, req->rq_buflen);
 166                 if (req->rq_md == NULL)
 167                         GOTO(out, rc = -ENOMEM);
 168
 169                 req->rq_oa = obdo_alloc();
 170                 if (req->rq_oa == NULL)
 171                         GOTO(out, rc = -ENOMEM);
 172
 173                 req->rq_idx = ost_idx;
 174                 req->rq_stripe = i;
 175                 /* create data objects with "parent" OA */
 176                 memcpy(req->rq_oa, src_oa, sizeof(*req->rq_oa));
 177
 178                 /* XXX When we start creating objects on demand, we need to
 179                  *     make sure that we always create the object on the
 180                  *     stripe which holds the existing file size.
 181                  */
 182                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
 183                         if (lov_stripe_offset(lsm, src_oa->o_size, i,
 184                                               &req->rq_oa->o_size) < 0 &&
 185                             req->rq_oa->o_size)
 186                                 req->rq_oa->o_size--;
 187
 188                         CDEBUG(D_INODE, "stripe %d has size "LPU64"/"LPU64"\n",
 189                                i, req->rq_oa->o_size, src_oa->o_size);
 190                 }
 191
 192                 lov_set_add_req(req, set);
 193
 194                 /* If we have allocated enough objects, we are OK */
 195                 if (set->set_count == lsm->lsm_stripe_count)
 196                         GOTO(out, rc = 0);
 197         }
 198
 199         if (set->set_count == 0)
 200                 GOTO(out, rc = -EIO);
 201
 202         /* If we were passed specific striping params, then a failure to
 203          * meet those requirements is an error, since we can't reallocate
 204          * that memory (it might be part of a larger array or something).
 205          *
 206          * We can only get here if lsm_stripe_count was originally > 1.
 207          */
 208         if (!newea) {
 209                 CERROR("can't lstripe objid "LPX64": have %u want %u, rc %d\n",
 210                        lsm->lsm_object_id, set->set_count,
 211                        lsm->lsm_stripe_count, rc);
 212                 rc = rc ? rc : -EFBIG;
 213         } else {
 214                 qos_shrink_lsm(set);
 215                 rc = 0;
 216         }
 217 out:
 218         RETURN(rc);
 219 }