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 Lustre, http://www.lustre.org.
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #ifndef EXPORT_SYMTAB
  23 # define EXPORT_SYMTAB
  24 #endif
  25 #define DEBUG_SUBSYSTEM S_LOV
  26
  27 #ifdef __KERNEL__
  28 #else
  29 #include <liblustre.h>
  30 #endif
  31
  32 #include <linux/obd_class.h>
  33 #include <linux/obd_lov.h>
  34
  35 #include "lov_internal.h"
  36
  37 void qos_shrink_lsm(struct lov_request_set *set)
  38 {
  39         struct lov_stripe_md *lsm = set->set_md;
  40         struct lov_stripe_md *lsm_new;
  41         /* XXX LOV STACKING call into osc for sizes */
  42         unsigned oldsize, newsize;
  43
  44         if (set->set_oti && set->set_cookies && set->set_cookie_sent) {
  45                 struct llog_cookie *cookies;
  46                 oldsize = lsm->lsm_stripe_count * sizeof(*cookies);
  47                 newsize = set->set_count * sizeof(*cookies);
  48
  49                 cookies = set->set_cookies;
  50                 oti_alloc_cookies(set->set_oti, set->set_count);
  51                 if (set->set_oti->oti_logcookies) {
  52                         memcpy(set->set_oti->oti_logcookies, cookies, newsize);
  53                         OBD_FREE(cookies, oldsize);
  54                         set->set_cookies = set->set_oti->oti_logcookies;
  55                 } else {
  56                         CWARN("'leaking' %d bytes\n", oldsize - newsize);
  57                 }
  58         }
  59
  60         CWARN("using fewer stripes for object "LPX64": old %u new %u\n",
  61               lsm->lsm_object_id, lsm->lsm_stripe_count, set->set_count);
  62
  63         oldsize = lov_stripe_md_size(lsm->lsm_stripe_count);
  64         newsize = lov_stripe_md_size(set->set_count);
  65         OBD_ALLOC(lsm_new, newsize);
  66         if (lsm_new != NULL) {
  67                 memcpy(lsm_new, lsm, newsize);
  68                 lsm_new->lsm_stripe_count = set->set_count;
  69                 OBD_FREE(lsm, oldsize);
  70                 set->set_md = lsm_new;
  71         } else {
  72                 CWARN("'leaking' %d bytes\n", oldsize - newsize);
  73         }
  74 }
  75
  76 #define LOV_CREATE_RESEED_INTERVAL 1000
  77 /* FIXME use real qos data to prepare the lov create request */
  78 int qos_prep_create(struct lov_obd *lov, struct lov_request_set *set, int newea)
  79 {
  80         static int ost_start_idx, ost_start_count;
  81         unsigned ost_idx, ost_count = lov->desc.ld_tgt_count;
  82         struct lov_stripe_md *lsm = set->set_md;
  83         struct obdo *src_oa = set->set_oa;
  84         int i, rc = 0;
  85         ENTRY;
  86
  87         LASSERT(src_oa->o_valid & OBD_MD_FLID);
  88
  89         lsm->lsm_object_id = src_oa->o_id;
  90         lsm->lsm_object_gr = src_oa->o_gr;
  91         if (!lsm->lsm_stripe_size)
  92                 lsm->lsm_stripe_size = lov->desc.ld_default_stripe_size;
  93         if (!lsm->lsm_pattern) {
  94                 lsm->lsm_pattern = lov->desc.ld_pattern ?
  95                         lov->desc.ld_pattern : LOV_PATTERN_RAID0;
  96         }
  97
  98         if (newea || lsm->lsm_oinfo[0].loi_ost_idx >= ost_count) {
  99                 if (--ost_start_count <= 0) {
 100                         ost_start_idx = ll_insecure_random_int();
 101                         ost_start_count = LOV_CREATE_RESEED_INTERVAL;
 102                 } else if (lsm->lsm_stripe_count >=
 103                            lov->desc.ld_active_tgt_count) {
 104                         /* If we allocate from all of the stripes, make the
 105                          * next file start on the next OST. */
 106                         ++ost_start_idx;
 107                 }
 108                 ost_idx = ost_start_idx % ost_count;
 109         } else {
 110                 ost_idx = lsm->lsm_oinfo[0].loi_ost_idx;
 111         }
 112
 113         CDEBUG(D_INODE, "allocating %d subobjs for objid "LPX64" at idx %d\n",
 114                lsm->lsm_stripe_count, lsm->lsm_object_id, ost_idx);
 115
 116         for (i = 0; i < ost_count; i++, ost_idx = (ost_idx + 1) % ost_count) {
 117                 struct lov_tgt_desc *tgt = lov->tgts + ost_idx;
 118                 struct lov_request *req;
 119
 120                 ++ost_start_idx;
 121                 if (!lov_tgt_active(lov, tgt, 0)) {
 122                         CDEBUG(D_HA, "lov idx %d inactive\n", ost_idx);
 123                         continue;
 124                 }
 125
 126                 OBD_ALLOC(req, sizeof(*req));
 127                 if (req == NULL) {
 128                         lov_tgt_decref(lov, tgt);
 129                         GOTO(out, rc = -ENOMEM);
 130                 }
 131
 132                 req->rq_buflen = sizeof(*req->rq_md);
 133                 OBD_ALLOC(req->rq_md, req->rq_buflen);
 134                 if (req->rq_md == NULL) {
 135                         OBD_FREE(req, sizeof(*req));
 136                         lov_tgt_decref(lov, tgt);
 137                         GOTO(out, rc = -ENOMEM);
 138                 }
 139
 140                 req->rq_oa = obdo_alloc();
 141                 if (req->rq_oa == NULL) {
 142                         OBD_FREE(req->rq_md, sizeof(*req->rq_md));
 143                         OBD_FREE(req, sizeof(*req));
 144                         lov_tgt_decref(lov, tgt);
 145                         GOTO(out, rc = -ENOMEM);
 146                 }
 147
 148                 req->rq_idx = ost_idx;
 149                 req->rq_gen = tgt->ltd_gen;
 150                 req->rq_stripe = i;
 151                 /* create data objects with "parent" OA */
 152                 memcpy(req->rq_oa, src_oa, sizeof(*req->rq_oa));
 153
 154                 /* XXX When we start creating objects on demand, we need to
 155                  *     make sure that we always create the object on the
 156                  *     stripe which holds the existing file size.
 157                  */
 158                 if (src_oa->o_valid & OBD_MD_FLSIZE) {
 159                         if (lov_stripe_offset(lsm, src_oa->o_size, i,
 160                                               &req->rq_oa->o_size) < 0 &&
 161                             req->rq_oa->o_size)
 162                                 req->rq_oa->o_size--;
 163
 164                         CDEBUG(D_INODE, "stripe %d has size "LPU64"/"LPU64"\n",
 165                                i, req->rq_oa->o_size, src_oa->o_size);
 166                 }
 167
 168                 lov_set_add_req(req, set);
 169
 170                 /* If we have allocated enough objects, we are OK */
 171                 if (set->set_count == lsm->lsm_stripe_count)
 172                         GOTO(out, rc = 0);
 173         }
 174
 175         if (set->set_count == 0)
 176                 GOTO(out, rc = -EIO);
 177
 178         /* If we were passed specific striping params, then a failure to
 179          * meet those requirements is an error, since we can't reallocate
 180          * that memory (it might be part of a larger array or something).
 181          *
 182          * We can only get here if lsm_stripe_count was originally > 1.
 183          */
 184         if (!newea) {
 185                 CERROR("can't lstripe objid "LPX64": have %u want %u, rc %d\n",
 186                        lsm->lsm_object_id, set->set_count,
 187                        lsm->lsm_stripe_count, rc);
 188                 rc = rc ? rc : -EFBIG;
 189         } else {
 190                 qos_shrink_lsm(set);
 191                 rc = 0;
 192         }
 193 out:
 194         RETURN(rc);
 195 }