X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Flod%2Flod_qos.c;h=7ee3d332814d5fbbb69e11096933197e06ffe9d0;hb=38b68e47e5e240fd8d394a944737ecdbcf2fb70f;hp=fbc72995c1a651230d4e39a7dcb0971761a3e903;hpb=976cbeb5ff1d32e7cac54478e6ff249cffe45116;p=fs%2Flustre-release.git diff --git a/lustre/lod/lod_qos.c b/lustre/lod/lod_qos.c index fbc7299..7ee3d33 100644 --- a/lustre/lod/lod_qos.c +++ b/lustre/lod/lod_qos.c @@ -6,13 +6,13 @@ * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 only, * as published by the Free Software Foundation. - + * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License version 2 for more details. A copy is * included in the COPYING file that accompanied this code. - + * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA @@ -23,7 +23,7 @@ * Copyright 2009 Sun Microsystems, Inc. All rights reserved * Use is subject to license terms. * - * Copyright (c) 2011, 2012, Whamcloud, Inc. + * Copyright (c) 2012, 2014, Intel Corporation. */ /* * This file is part of Lustre, http://www.lustre.org/ @@ -31,13 +31,15 @@ * * lustre/lod/lod_qos.c * + * Implementation of different allocation algorithm used + * to distribute objects and data among OSTs. */ #define DEBUG_SUBSYSTEM S_LOV +#include #include #include -#include #include #include "lod_internal.h" @@ -48,32 +50,40 @@ #define D_QOS D_OTHER -#if 0 -#define QOS_DEBUG(fmt, ...) CDEBUG(D_OTHER, fmt, ## __VA_ARGS__) -#define QOS_CONSOLE(fmt, ...) LCONSOLE(D_OTHER, fmt, ## __VA_ARGS__) -#else -#define QOS_DEBUG(fmt, ...) -#define QOS_CONSOLE(fmt, ...) -#endif +#define QOS_DEBUG(fmt, ...) CDEBUG(D_QOS, fmt, ## __VA_ARGS__) +#define QOS_CONSOLE(fmt, ...) LCONSOLE(D_QOS, fmt, ## __VA_ARGS__) #define TGT_BAVAIL(i) (OST_TGT(lod,i)->ltd_statfs.os_bavail * \ OST_TGT(lod,i)->ltd_statfs.os_bsize) -int qos_add_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) +/** + * Add a new target to Quality of Service (QoS) target table. + * + * Add a new OST target to the structure representing an OSS. Resort the list + * of known OSSs by the number of OSTs attached to each OSS. The OSS list is + * protected internally and no external locking is required. + * + * \param[in] lod LOD device + * \param[in] ost_desc OST description + * + * \retval 0 on success + * \retval -ENOMEM on error + */ +int qos_add_tgt(struct lod_device *lod, struct lod_tgt_desc *ost_desc) { - struct lov_qos_oss *oss = NULL, *temposs; + struct lod_qos_oss *oss = NULL, *temposs; struct obd_export *exp = ost_desc->ltd_exp; int rc = 0, found = 0; - cfs_list_t *list; + struct list_head *list; ENTRY; - cfs_down_write(&lod->lod_qos.lq_rw_sem); + down_write(&lod->lod_qos.lq_rw_sem); /* * a bit hacky approach to learn NID of corresponding connection * but there is no official API to access information like this * with OSD API. */ - cfs_list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) { + list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) { if (obd_uuid_equals(&oss->lqo_uuid, &exp->exp_connection->c_remote_uuid)) { found++; @@ -89,7 +99,7 @@ int qos_add_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) sizeof(oss->lqo_uuid)); } else { /* Assume we have to move this one */ - cfs_list_del(&oss->lqo_oss_list); + list_del(&oss->lqo_oss_list); } oss->lqo_ost_count++; @@ -102,29 +112,41 @@ int qos_add_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) /* Add sorted by # of OSTs. Find the first entry that we're bigger than... */ list = &lod->lod_qos.lq_oss_list; - cfs_list_for_each_entry(temposs, list, lqo_oss_list) { + list_for_each_entry(temposs, list, lqo_oss_list) { if (oss->lqo_ost_count > temposs->lqo_ost_count) break; } /* ...and add before it. If we're the first or smallest, temposs points to the list head, and we add to the end. */ - cfs_list_add_tail(&oss->lqo_oss_list, &temposs->lqo_oss_list); + list_add_tail(&oss->lqo_oss_list, &temposs->lqo_oss_list); lod->lod_qos.lq_dirty = 1; lod->lod_qos.lq_rr.lqr_dirty = 1; out: - cfs_up_write(&lod->lod_qos.lq_rw_sem); + up_write(&lod->lod_qos.lq_rw_sem); RETURN(rc); } -int qos_del_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) +/** + * Remove OST target from QoS table. + * + * Removes given OST target from QoS table and releases related OSS structure + * if no OSTs remain on the OSS. + * + * \param[in] lod LOD device + * \param[in] ost_desc OST description + * + * \retval 0 on success + * \retval -ENOENT if no OSS was found + */ +int qos_del_tgt(struct lod_device *lod, struct lod_tgt_desc *ost_desc) { - struct lov_qos_oss *oss; + struct lod_qos_oss *oss; int rc = 0; ENTRY; - cfs_down_write(&lod->lod_qos.lq_rw_sem); + down_write(&lod->lod_qos.lq_rw_sem); oss = ost_desc->ltd_qos.ltq_oss; if (!oss) GOTO(out, rc = -ENOENT); @@ -133,7 +155,7 @@ int qos_del_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) if (oss->lqo_ost_count == 0) { CDEBUG(D_QOS, "removing OSS %s\n", obd_uuid2str(&oss->lqo_uuid)); - cfs_list_del(&oss->lqo_oss_list); + list_del(&oss->lqo_oss_list); ost_desc->ltd_qos.ltq_oss = NULL; OBD_FREE_PTR(oss); } @@ -141,7 +163,1753 @@ int qos_del_tgt(struct lod_device *lod, struct lod_ost_desc *ost_desc) lod->lod_qos.lq_dirty = 1; lod->lod_qos.lq_rr.lqr_dirty = 1; out: - cfs_up_write(&lod->lod_qos.lq_rw_sem); + up_write(&lod->lod_qos.lq_rw_sem); + RETURN(rc); +} + +/** + * Check whether the target is available for new OST objects. + * + * Request statfs data from the given target and verify it's active and not + * read-only. If so, then it can be used to place new OST objects. This + * function also maintains the number of active/inactive targets and sets + * dirty flags if those numbers change so others can run re-balance procedures. + * No external locking is required. + * + * \param[in] env execution environment for this thread + * \param[in] d LOD device + * \param[in] index index of OST target to check + * \param[out] sfs buffer for statfs data + * + * \retval 0 if the target is good + * \retval negative negated errno on error + + */ +static int lod_statfs_and_check(const struct lu_env *env, struct lod_device *d, + int index, struct obd_statfs *sfs) +{ + struct lod_tgt_desc *ost; + int rc; + ENTRY; + + LASSERT(d); + ost = OST_TGT(d,index); + LASSERT(ost); + + rc = dt_statfs(env, ost->ltd_ost, sfs); + if (rc && rc != -ENOTCONN) + CERROR("%s: statfs: rc = %d\n", lod2obd(d)->obd_name, rc); + + /* If the OST is readonly then we can't allocate objects there */ + if (sfs->os_state & OS_STATE_READONLY) + rc = -EROFS; + + /* check whether device has changed state (active, inactive) */ + if (rc != 0 && ost->ltd_active) { + /* turned inactive? */ + spin_lock(&d->lod_desc_lock); + if (ost->ltd_active) { + ost->ltd_active = 0; + LASSERT(d->lod_desc.ld_active_tgt_count > 0); + d->lod_desc.ld_active_tgt_count--; + d->lod_qos.lq_dirty = 1; + d->lod_qos.lq_rr.lqr_dirty = 1; + CDEBUG(D_CONFIG, "%s: turns inactive\n", + ost->ltd_exp->exp_obd->obd_name); + } + spin_unlock(&d->lod_desc_lock); + } else if (rc == 0 && ost->ltd_active == 0) { + /* turned active? */ + LASSERTF(d->lod_desc.ld_active_tgt_count < d->lod_ostnr, + "active tgt count %d, ost nr %d\n", + d->lod_desc.ld_active_tgt_count, d->lod_ostnr); + spin_lock(&d->lod_desc_lock); + if (ost->ltd_active == 0) { + ost->ltd_active = 1; + d->lod_desc.ld_active_tgt_count++; + d->lod_qos.lq_dirty = 1; + d->lod_qos.lq_rr.lqr_dirty = 1; + CDEBUG(D_CONFIG, "%s: turns active\n", + ost->ltd_exp->exp_obd->obd_name); + } + spin_unlock(&d->lod_desc_lock); + } + + RETURN(rc); +} + +/** + * Maintain per-target statfs data. + * + * The function refreshes statfs data for all the targets every N seconds. + * The actual N is controlled via procfs and set to LOV_DESC_QOS_MAXAGE_DEFAULT + * initially. + * + * \param[in] env execution environment for this thread + * \param[in] lod LOD device + */ +static void lod_qos_statfs_update(const struct lu_env *env, + struct lod_device *lod) +{ + struct obd_device *obd = lod2obd(lod); + struct ost_pool *osts = &(lod->lod_pool_info); + unsigned int i; + int idx; + __u64 max_age, avail; + ENTRY; + + max_age = cfs_time_shift_64(-2 * lod->lod_desc.ld_qos_maxage); + + if (cfs_time_beforeq_64(max_age, obd->obd_osfs_age)) + /* statfs data are quite recent, don't need to refresh it */ + RETURN_EXIT; + + down_write(&lod->lod_qos.lq_rw_sem); + if (cfs_time_beforeq_64(max_age, obd->obd_osfs_age)) + goto out; + + for (i = 0; i < osts->op_count; i++) { + idx = osts->op_array[i]; + avail = OST_TGT(lod,idx)->ltd_statfs.os_bavail; + if (lod_statfs_and_check(env, lod, idx, + &OST_TGT(lod, idx)->ltd_statfs)) + continue; + if (OST_TGT(lod,idx)->ltd_statfs.os_bavail != avail) + /* recalculate weigths */ + lod->lod_qos.lq_dirty = 1; + } + obd->obd_osfs_age = cfs_time_current_64(); + +out: + up_write(&lod->lod_qos.lq_rw_sem); + EXIT; +} + +/** + * Calculate per-OST and per-OSS penalties + * + * Re-calculate penalties when the configuration changes, active targets + * change and after statfs refresh (all these are reflected by lq_dirty flag). + * On every OST and OSS: decay the penalty by half for every 8x the update + * interval that the device has been idle. That gives lots of time for the + * statfs information to be updated (which the penalty is only a proxy for), + * and avoids penalizing OSS/OSTs under light load. + * See lod_qos_calc_weight() for how penalties are factored into the weight. + * + * \param[in] lod LOD device + * + * \retval 0 on success + * \retval -EAGAIN the number of OSTs isn't enough + */ +static int lod_qos_calc_ppo(struct lod_device *lod) +{ + struct lod_qos_oss *oss; + __u64 ba_max, ba_min, temp; + __u32 num_active; + unsigned int i; + int rc, prio_wide; + time_t now, age; + ENTRY; + + if (!lod->lod_qos.lq_dirty) + GOTO(out, rc = 0); + + num_active = lod->lod_desc.ld_active_tgt_count - 1; + if (num_active < 1) + GOTO(out, rc = -EAGAIN); + + /* find bavail on each OSS */ + list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) + oss->lqo_bavail = 0; + lod->lod_qos.lq_active_oss_count = 0; + + /* + * How badly user wants to select OSTs "widely" (not recently chosen + * and not on recent OSS's). As opposed to "freely" (free space + * avail.) 0-256 + */ + prio_wide = 256 - lod->lod_qos.lq_prio_free; + + ba_min = (__u64)(-1); + ba_max = 0; + now = cfs_time_current_sec(); + /* Calculate OST penalty per object + * (lod ref taken in lod_qos_prep_create()) */ + cfs_foreach_bit(lod->lod_ost_bitmap, i) { + LASSERT(OST_TGT(lod,i)); + temp = TGT_BAVAIL(i); + if (!temp) + continue; + ba_min = min(temp, ba_min); + ba_max = max(temp, ba_max); + + /* Count the number of usable OSS's */ + if (OST_TGT(lod,i)->ltd_qos.ltq_oss->lqo_bavail == 0) + lod->lod_qos.lq_active_oss_count++; + OST_TGT(lod,i)->ltd_qos.ltq_oss->lqo_bavail += temp; + + /* per-OST penalty is prio * TGT_bavail / (num_ost - 1) / 2 */ + temp >>= 1; + do_div(temp, num_active); + OST_TGT(lod,i)->ltd_qos.ltq_penalty_per_obj = + (temp * prio_wide) >> 8; + + age = (now - OST_TGT(lod,i)->ltd_qos.ltq_used) >> 3; + if (lod->lod_qos.lq_reset || + age > 32 * lod->lod_desc.ld_qos_maxage) + OST_TGT(lod,i)->ltd_qos.ltq_penalty = 0; + else if (age > lod->lod_desc.ld_qos_maxage) + /* Decay OST penalty. */ + OST_TGT(lod,i)->ltd_qos.ltq_penalty >>= + (age / lod->lod_desc.ld_qos_maxage); + } + + num_active = lod->lod_qos.lq_active_oss_count - 1; + if (num_active < 1) { + /* If there's only 1 OSS, we can't penalize it, so instead + we have to double the OST penalty */ + num_active = 1; + cfs_foreach_bit(lod->lod_ost_bitmap, i) + OST_TGT(lod,i)->ltd_qos.ltq_penalty_per_obj <<= 1; + } + + /* Per-OSS penalty is prio * oss_avail / oss_osts / (num_oss - 1) / 2 */ + list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) { + temp = oss->lqo_bavail >> 1; + do_div(temp, oss->lqo_ost_count * num_active); + oss->lqo_penalty_per_obj = (temp * prio_wide) >> 8; + + age = (now - oss->lqo_used) >> 3; + if (lod->lod_qos.lq_reset || + age > 32 * lod->lod_desc.ld_qos_maxage) + oss->lqo_penalty = 0; + else if (age > lod->lod_desc.ld_qos_maxage) + /* Decay OSS penalty. */ + oss->lqo_penalty >>= age / lod->lod_desc.ld_qos_maxage; + } + + lod->lod_qos.lq_dirty = 0; + lod->lod_qos.lq_reset = 0; + + /* If each ost has almost same free space, + * do rr allocation for better creation performance */ + lod->lod_qos.lq_same_space = 0; + if ((ba_max * (256 - lod->lod_qos.lq_threshold_rr)) >> 8 < ba_min) { + lod->lod_qos.lq_same_space = 1; + /* Reset weights for the next time we enter qos mode */ + lod->lod_qos.lq_reset = 1; + } + rc = 0; + +out: +#ifndef FORCE_QOS + if (!rc && lod->lod_qos.lq_same_space) + RETURN(-EAGAIN); +#endif + RETURN(rc); +} + +/** + * Calculate weight for a given OST target. + * + * The final OST weight is the number of bytes available minus the OST and + * OSS penalties. See lod_qos_calc_ppo() for how penalties are calculated. + * + * \param[in] lod LOD device, where OST targets are listed + * \param[in] i OST target index + * + * \retval 0 + */ +static int lod_qos_calc_weight(struct lod_device *lod, int i) +{ + __u64 temp, temp2; + + temp = TGT_BAVAIL(i); + temp2 = OST_TGT(lod,i)->ltd_qos.ltq_penalty + + OST_TGT(lod,i)->ltd_qos.ltq_oss->lqo_penalty; + if (temp < temp2) + OST_TGT(lod,i)->ltd_qos.ltq_weight = 0; + else + OST_TGT(lod,i)->ltd_qos.ltq_weight = temp - temp2; + return 0; +} + +/** + * Re-calculate weights. + * + * The function is called when some OST target was used for a new object. In + * this case we should re-calculate all the weights to keep new allocations + * balanced well. + * + * \param[in] lod LOD device + * \param[in] osts OST pool where a new object was placed + * \param[in] index OST target where a new object was placed + * \param[out] total_wt new total weight for the pool + * + * \retval 0 + */ +static int lod_qos_used(struct lod_device *lod, struct ost_pool *osts, + __u32 index, __u64 *total_wt) +{ + struct lod_tgt_desc *ost; + struct lod_qos_oss *oss; + unsigned int j; + ENTRY; + + ost = OST_TGT(lod,index); + LASSERT(ost); + + /* Don't allocate on this devuce anymore, until the next alloc_qos */ + ost->ltd_qos.ltq_usable = 0; + + oss = ost->ltd_qos.ltq_oss; + + /* Decay old penalty by half (we're adding max penalty, and don't + want it to run away.) */ + ost->ltd_qos.ltq_penalty >>= 1; + oss->lqo_penalty >>= 1; + + /* mark the OSS and OST as recently used */ + ost->ltd_qos.ltq_used = oss->lqo_used = cfs_time_current_sec(); + + /* Set max penalties for this OST and OSS */ + ost->ltd_qos.ltq_penalty += + ost->ltd_qos.ltq_penalty_per_obj * lod->lod_ostnr; + oss->lqo_penalty += oss->lqo_penalty_per_obj * + lod->lod_qos.lq_active_oss_count; + + /* Decrease all OSS penalties */ + list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) { + if (oss->lqo_penalty < oss->lqo_penalty_per_obj) + oss->lqo_penalty = 0; + else + oss->lqo_penalty -= oss->lqo_penalty_per_obj; + } + + *total_wt = 0; + /* Decrease all OST penalties */ + for (j = 0; j < osts->op_count; j++) { + int i; + + i = osts->op_array[j]; + if (!cfs_bitmap_check(lod->lod_ost_bitmap, i)) + continue; + + ost = OST_TGT(lod,i); + LASSERT(ost); + + if (ost->ltd_qos.ltq_penalty < + ost->ltd_qos.ltq_penalty_per_obj) + ost->ltd_qos.ltq_penalty = 0; + else + ost->ltd_qos.ltq_penalty -= + ost->ltd_qos.ltq_penalty_per_obj; + + lod_qos_calc_weight(lod, i); + + /* Recalc the total weight of usable osts */ + if (ost->ltd_qos.ltq_usable) + *total_wt += ost->ltd_qos.ltq_weight; + + QOS_DEBUG("recalc tgt %d usable=%d avail="LPU64 + " ostppo="LPU64" ostp="LPU64" ossppo="LPU64 + " ossp="LPU64" wt="LPU64"\n", + i, ost->ltd_qos.ltq_usable, TGT_BAVAIL(i) >> 10, + ost->ltd_qos.ltq_penalty_per_obj >> 10, + ost->ltd_qos.ltq_penalty >> 10, + ost->ltd_qos.ltq_oss->lqo_penalty_per_obj >> 10, + ost->ltd_qos.ltq_oss->lqo_penalty >> 10, + ost->ltd_qos.ltq_weight >> 10); + } + + RETURN(0); +} + +#define LOV_QOS_EMPTY ((__u32)-1) + +/** + * Calculate optimal round-robin order with regard to OSSes. + * + * Place all the OSTs from pool \a src_pool in a special array to be used for + * round-robin (RR) stripe allocation. The placement algorithm interleaves + * OSTs from the different OSSs so that RR allocation can balance OSSs evenly. + * Resorts the targets when the number of active targets changes (because of + * a new target or activation/deactivation). + * + * \param[in] lod LOD device + * \param[in] src_pool OST pool + * \param[in] lqr round-robin list + * + * \retval 0 on success + * \retval -ENOMEM fails to allocate the array + */ +static int lod_qos_calc_rr(struct lod_device *lod, struct ost_pool *src_pool, + struct lod_qos_rr *lqr) +{ + struct lod_qos_oss *oss; + struct lod_tgt_desc *ost; + unsigned placed, real_count; + unsigned int i; + int rc; + ENTRY; + + if (!lqr->lqr_dirty) { + LASSERT(lqr->lqr_pool.op_size); + RETURN(0); + } + + /* Do actual allocation. */ + down_write(&lod->lod_qos.lq_rw_sem); + + /* + * Check again. While we were sleeping on @lq_rw_sem something could + * change. + */ + if (!lqr->lqr_dirty) { + LASSERT(lqr->lqr_pool.op_size); + up_write(&lod->lod_qos.lq_rw_sem); + RETURN(0); + } + + real_count = src_pool->op_count; + + /* Zero the pool array */ + /* alloc_rr is holding a read lock on the pool, so nobody is adding/ + deleting from the pool. The lq_rw_sem insures that nobody else + is reading. */ + lqr->lqr_pool.op_count = real_count; + rc = lod_ost_pool_extend(&lqr->lqr_pool, real_count); + if (rc) { + up_write(&lod->lod_qos.lq_rw_sem); + RETURN(rc); + } + for (i = 0; i < lqr->lqr_pool.op_count; i++) + lqr->lqr_pool.op_array[i] = LOV_QOS_EMPTY; + + /* Place all the OSTs from 1 OSS at the same time. */ + placed = 0; + list_for_each_entry(oss, &lod->lod_qos.lq_oss_list, lqo_oss_list) { + int j = 0; + + for (i = 0; i < lqr->lqr_pool.op_count; i++) { + int next; + + if (!cfs_bitmap_check(lod->lod_ost_bitmap, + src_pool->op_array[i])) + continue; + + ost = OST_TGT(lod,src_pool->op_array[i]); + LASSERT(ost && ost->ltd_ost); + if (ost->ltd_qos.ltq_oss != oss) + continue; + + /* Evenly space these OSTs across arrayspace */ + next = j * lqr->lqr_pool.op_count / oss->lqo_ost_count; + while (lqr->lqr_pool.op_array[next] != LOV_QOS_EMPTY) + next = (next + 1) % lqr->lqr_pool.op_count; + + lqr->lqr_pool.op_array[next] = src_pool->op_array[i]; + j++; + placed++; + } + } + + lqr->lqr_dirty = 0; + up_write(&lod->lod_qos.lq_rw_sem); + + if (placed != real_count) { + /* This should never happen */ + LCONSOLE_ERROR_MSG(0x14e, "Failed to place all OSTs in the " + "round-robin list (%d of %d).\n", + placed, real_count); + for (i = 0; i < lqr->lqr_pool.op_count; i++) { + LCONSOLE(D_WARNING, "rr #%d ost idx=%d\n", i, + lqr->lqr_pool.op_array[i]); + } + lqr->lqr_dirty = 1; + RETURN(-EAGAIN); + } + +#if 0 + for (i = 0; i < lqr->lqr_pool.op_count; i++) + QOS_CONSOLE("rr #%d ost idx=%d\n", i, lqr->lqr_pool.op_array[i]); +#endif + + RETURN(0); +} + +/** + * Instantiate and declare creation of a new object. + * + * The function instantiates LU representation for a new object on the + * specified device. Also it declares an intention to create that + * object on the storage target. + * + * Note lu_object_anon() is used which is a trick with regard to LU/OSD + * infrastructure - in the existing precreation framework we can't assign FID + * at this moment, we do this later once a transaction is started. So the + * special method instantiates FID-less object in the cache and later it + * will get a FID and proper placement in LU cache. + * + * \param[in] env execution environment for this thread + * \param[in] d LOD device + * \param[in] ost_idx OST target index where the object is being created + * \param[in] th transaction handle + * + * \retval object ptr on success, ERR_PTR() otherwise + */ +static struct dt_object *lod_qos_declare_object_on(const struct lu_env *env, + struct lod_device *d, + __u32 ost_idx, + struct thandle *th) +{ + struct lod_tgt_desc *ost; + struct lu_object *o, *n; + struct lu_device *nd; + struct dt_object *dt; + int rc; + ENTRY; + + LASSERT(d); + LASSERT(ost_idx < d->lod_osts_size); + ost = OST_TGT(d,ost_idx); + LASSERT(ost); + LASSERT(ost->ltd_ost); + + nd = &ost->ltd_ost->dd_lu_dev; + + /* + * allocate anonymous object with zero fid, real fid + * will be assigned by OSP within transaction + * XXX: to be fixed with fully-functional OST fids + */ + o = lu_object_anon(env, nd, NULL); + if (IS_ERR(o)) + GOTO(out, dt = ERR_PTR(PTR_ERR(o))); + + n = lu_object_locate(o->lo_header, nd->ld_type); + if (unlikely(n == NULL)) { + CERROR("can't find slice\n"); + lu_object_put(env, o); + GOTO(out, dt = ERR_PTR(-EINVAL)); + } + + dt = container_of(n, struct dt_object, do_lu); + + rc = lod_sub_object_declare_create(env, dt, NULL, NULL, NULL, th); + if (rc < 0) { + CDEBUG(D_OTHER, "can't declare creation on #%u: %d\n", + ost_idx, rc); + lu_object_put(env, o); + dt = ERR_PTR(rc); + } + +out: + RETURN(dt); +} + +/** + * Calculate a minimum acceptable stripe count. + * + * Return an acceptable stripe count depending on flag LOV_USES_DEFAULT_STRIPE: + * all stripes or 3/4 of stripes. + * + * \param[in] stripe_cnt number of stripes requested + * \param[in] flags 0 or LOV_USES_DEFAULT_STRIPE + * + * \retval acceptable stripecount + */ +static int min_stripe_count(__u32 stripe_cnt, int flags) +{ + return (flags & LOV_USES_DEFAULT_STRIPE ? + stripe_cnt - (stripe_cnt / 4) : stripe_cnt); +} + +#define LOV_CREATE_RESEED_MULT 30 +#define LOV_CREATE_RESEED_MIN 2000 + +/** + * Check if an OST is full. + * + * Check whether an OST should be considered full based + * on the given statfs data. + * + * \param[in] msfs statfs data + * + * \retval false not full + * \retval true full + */ +static int inline lod_qos_dev_is_full(struct obd_statfs *msfs) +{ + __u64 used; + int bs = msfs->os_bsize; + + LASSERT(((bs - 1) & bs) == 0); + + /* the minimum of 0.1% used blocks and 1GB bytes. */ + used = min_t(__u64, (msfs->os_blocks - msfs->os_bfree) >> 10, + 1 << (31 - ffs(bs))); + return (msfs->os_bavail < used); +} + +/** + * Initialize temporary OST-in-use array. + * + * Allocate or extend the array used to mark targets already assigned to a new + * striping so they are not used more than once. + * + * \param[in] env execution environment for this thread + * \param[in] stripes number of items needed in the array + * + * \retval 0 on success + * \retval -ENOMEM on error + */ +static inline int lod_qos_ost_in_use_clear(const struct lu_env *env, + __u32 stripes) +{ + struct lod_thread_info *info = lod_env_info(env); + + if (info->lti_ea_store_size < sizeof(int) * stripes) + lod_ea_store_resize(info, stripes * sizeof(int)); + if (info->lti_ea_store_size < sizeof(int) * stripes) { + CERROR("can't allocate memory for ost-in-use array\n"); + return -ENOMEM; + } + memset(info->lti_ea_store, -1, sizeof(int) * stripes); + return 0; +} + +/** + * Remember a target in the array of used targets. + * + * Mark the given target as used for a new striping being created. The status + * of an OST in a striping can be checked with lod_qos_is_ost_used(). + * + * \param[in] env execution environment for this thread + * \param[in] idx index in the array + * \param[in] ost OST target index to mark as used + */ +static inline void lod_qos_ost_in_use(const struct lu_env *env, + int idx, int ost) +{ + struct lod_thread_info *info = lod_env_info(env); + int *osts = info->lti_ea_store; + + LASSERT(info->lti_ea_store_size >= idx * sizeof(int)); + osts[idx] = ost; +} + +/** + * Check is OST used in a striping. + * + * Checks whether OST with the given index is marked as used in the temporary + * array (see lod_qos_ost_in_use()). + * + * \param[in] env execution environment for this thread + * \param[in] ost OST target index to check + * \param[in] stripes the number of items used in the array already + * + * \retval 0 not used + * \retval 1 used + */ +static int lod_qos_is_ost_used(const struct lu_env *env, int ost, __u32 stripes) +{ + struct lod_thread_info *info = lod_env_info(env); + int *osts = info->lti_ea_store; + __u32 j; + + for (j = 0; j < stripes; j++) { + if (osts[j] == ost) + return 1; + } + return 0; +} + +/** + * Allocate a striping using round-robin algorigthm. + * + * Allocates a new striping using round-robin algorithm. The function refreshes + * all the internal structures (statfs cache, array of available OSTs sorted + * with regard to OSS, etc). The number of stripes required is taken from the + * object (must be prepared by the caller), but can change if the flag + * LOV_USES_DEFAULT_STRIPE is supplied. The caller should ensure nobody else + * is trying to create a striping on the object in parallel. All the internal + * structures (like pools, etc) are protected and no additional locking is + * required. The function succeeds even if a single stripe is allocated. To save + * time we give priority to targets which already have objects precreated. + * Full OSTs are skipped (see lod_qos_dev_is_full() for the details). + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[out] stripe striping created + * \param[in] flags allocation flags (0 or LOV_USES_DEFAULT_STRIPE) + * \param[in] th transaction handle + * + * \retval 0 on success + * \retval -ENOSPC if not enough OSTs are found + * \retval negative negated errno for other failures + */ +static int lod_alloc_rr(const struct lu_env *env, struct lod_object *lo, + struct dt_object **stripe, int flags, + struct thandle *th) +{ + struct lod_device *m = lu2lod_dev(lo->ldo_obj.do_lu.lo_dev); + struct obd_statfs *sfs = &lod_env_info(env)->lti_osfs; + struct pool_desc *pool = NULL; + struct ost_pool *osts; + struct lod_qos_rr *lqr; + struct dt_object *o; + unsigned int i, array_idx; + int rc; + __u32 ost_start_idx_temp; + int speed = 0; + __u32 stripe_idx = 0; + __u32 stripe_cnt = lo->ldo_stripenr; + __u32 stripe_cnt_min = min_stripe_count(stripe_cnt, flags); + __u32 ost_idx; + ENTRY; + + if (lo->ldo_pool) + pool = lod_find_pool(m, lo->ldo_pool); + + if (pool != NULL) { + down_read(&pool_tgt_rw_sem(pool)); + osts = &(pool->pool_obds); + lqr = &(pool->pool_rr); + } else { + osts = &(m->lod_pool_info); + lqr = &(m->lod_qos.lq_rr); + } + + rc = lod_qos_calc_rr(m, osts, lqr); + if (rc) + GOTO(out, rc); + + rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr); + if (rc) + GOTO(out, rc); + + if (--lqr->lqr_start_count <= 0) { + lqr->lqr_start_idx = cfs_rand() % osts->op_count; + lqr->lqr_start_count = + (LOV_CREATE_RESEED_MIN / max(osts->op_count, 1U) + + LOV_CREATE_RESEED_MULT) * max(osts->op_count, 1U); + } else if (stripe_cnt_min >= osts->op_count || + lqr->lqr_start_idx > osts->op_count) { + /* If we have allocated from all of the OSTs, slowly + * precess the next start if the OST/stripe count isn't + * already doing this for us. */ + lqr->lqr_start_idx %= osts->op_count; + if (stripe_cnt > 1 && (osts->op_count % stripe_cnt) != 1) + ++lqr->lqr_offset_idx; + } + down_read(&m->lod_qos.lq_rw_sem); + ost_start_idx_temp = lqr->lqr_start_idx; + +repeat_find: + array_idx = (lqr->lqr_start_idx + lqr->lqr_offset_idx) % + osts->op_count; + + QOS_DEBUG("pool '%s' want %d startidx %d startcnt %d offset %d " + "active %d count %d arrayidx %d\n", + lo->ldo_pool ? lo->ldo_pool : "", + stripe_cnt, lqr->lqr_start_idx, lqr->lqr_start_count, + lqr->lqr_offset_idx, osts->op_count, osts->op_count, + array_idx); + + for (i = 0; i < osts->op_count && stripe_idx < lo->ldo_stripenr; + i++, array_idx = (array_idx + 1) % osts->op_count) { + ++lqr->lqr_start_idx; + ost_idx = lqr->lqr_pool.op_array[array_idx]; + + QOS_DEBUG("#%d strt %d act %d strp %d ary %d idx %d\n", + i, lqr->lqr_start_idx, /* XXX: active*/ 0, + stripe_idx, array_idx, ost_idx); + + if ((ost_idx == LOV_QOS_EMPTY) || + !cfs_bitmap_check(m->lod_ost_bitmap, ost_idx)) + continue; + + /* Fail Check before osc_precreate() is called + so we can only 'fail' single OSC. */ + if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0) + continue; + + rc = lod_statfs_and_check(env, m, ost_idx, sfs); + if (rc) { + /* this OSP doesn't feel well */ + continue; + } + + /* + * skip full devices + */ + if (lod_qos_dev_is_full(sfs)) { + QOS_DEBUG("#%d is full\n", ost_idx); + continue; + } + + /* + * We expect number of precreated objects in f_ffree at + * the first iteration, skip OSPs with no objects ready + */ + if (sfs->os_fprecreated == 0 && speed == 0) { + QOS_DEBUG("#%d: precreation is empty\n", ost_idx); + continue; + } + + /* + * try to use another OSP if this one is degraded + */ + if (sfs->os_state & OS_STATE_DEGRADED && speed < 2) { + QOS_DEBUG("#%d: degraded\n", ost_idx); + continue; + } + + /* + * do not put >1 objects on a single OST + */ + if (speed && lod_qos_is_ost_used(env, ost_idx, stripe_idx)) + continue; + + o = lod_qos_declare_object_on(env, m, ost_idx, th); + if (IS_ERR(o)) { + CDEBUG(D_OTHER, "can't declare new object on #%u: %d\n", + ost_idx, (int) PTR_ERR(o)); + rc = PTR_ERR(o); + continue; + } + + /* + * We've successfuly declared (reserved) an object + */ + lod_qos_ost_in_use(env, stripe_idx, ost_idx); + stripe[stripe_idx] = o; + stripe_idx++; + + } + if ((speed < 2) && (stripe_idx < stripe_cnt_min)) { + /* Try again, allowing slower OSCs */ + speed++; + lqr->lqr_start_idx = ost_start_idx_temp; + goto repeat_find; + } + + up_read(&m->lod_qos.lq_rw_sem); + + if (stripe_idx) { + lo->ldo_stripenr = stripe_idx; + /* at least one stripe is allocated */ + rc = 0; + } else { + /* nobody provided us with a single object */ + rc = -ENOSPC; + } + +out: + if (pool != NULL) { + up_read(&pool_tgt_rw_sem(pool)); + /* put back ref got by lod_find_pool() */ + lod_pool_putref(pool); + } + + RETURN(rc); +} + +/** + * Allocate a specific striping layout on a user defined set of OSTs. + * + * Allocates new striping using the OST index range provided by the data from + * the lmm_obejcts contained in the lov_user_md passed to this method. Full + * OSTs are not considered. The exact order of OSTs requested by the user + * is respected as much as possible depending on OST status. The number of + * stripes needed and stripe offset are taken from the object. If that number + * can not be met, then the function returns a failure and then it's the + * caller's responsibility to release the stripes allocated. All the internal + * structures are protected, but no concurrent allocation is allowed on the + * same objects. + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[out] stripe striping created + * \param[in] lum stripe md to specify list of OSTs + * \param[in] th transaction handle + * + * \retval 0 on success + * \retval -ENODEV OST index does not exist on file system + * \retval -EINVAL requested OST index is invalid + * \retval negative negated errno on error + */ +static int lod_alloc_ost_list(const struct lu_env *env, + struct lod_object *lo, struct dt_object **stripe, + struct lov_user_md *lum, struct thandle *th) +{ + struct lod_device *m = lu2lod_dev(lo->ldo_obj.do_lu.lo_dev); + struct obd_statfs *sfs = &lod_env_info(env)->lti_osfs; + struct dt_object *o; + struct lov_user_md_v3 *v3; + unsigned int array_idx = 0; + int stripe_count = 0; + int i; + int rc; + ENTRY; + + /* for specific OSTs layout */ + LASSERT(lum != NULL && lum->lmm_magic == LOV_USER_MAGIC_SPECIFIC); + lustre_print_user_md(D_OTHER, lum, __func__); + + rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr); + if (rc < 0) + RETURN(rc); + + v3 = (struct lov_user_md_v3 *)lum; + for (i = 0; i < lo->ldo_stripenr; i++) { + if (v3->lmm_objects[i].l_ost_idx == lo->ldo_def_stripe_offset) { + array_idx = i; + break; + } + } + if (i == lo->ldo_stripenr) { + CDEBUG(D_OTHER, + "%s: start index %d not in the specified list of OSTs\n", + lod2obd(m)->obd_name, lo->ldo_def_stripe_offset); + RETURN(-EINVAL); + } + + for (i = 0; i < lo->ldo_stripenr; + i++, array_idx = (array_idx + 1) % lo->ldo_stripenr) { + __u32 ost_idx = v3->lmm_objects[array_idx].l_ost_idx; + + if (!cfs_bitmap_check(m->lod_ost_bitmap, ost_idx)) { + rc = -ENODEV; + break; + } + + /* + * do not put >1 objects on a single OST + */ + if (lod_qos_is_ost_used(env, ost_idx, stripe_count)) { + rc = -EINVAL; + break; + } + + rc = lod_statfs_and_check(env, m, ost_idx, sfs); + if (rc < 0) /* this OSP doesn't feel well */ + break; + + o = lod_qos_declare_object_on(env, m, ost_idx, th); + if (IS_ERR(o)) { + rc = PTR_ERR(o); + CDEBUG(D_OTHER, + "%s: can't declare new object on #%u: %d\n", + lod2obd(m)->obd_name, ost_idx, rc); + break; + } + + /* + * We've successfuly declared (reserved) an object + */ + lod_qos_ost_in_use(env, stripe_count, ost_idx); + stripe[stripe_count] = o; + stripe_count++; + } + + RETURN(rc); +} + +/** + * Allocate a striping on a predefined set of OSTs. + * + * Allocates new striping starting from OST provided lo->ldo_def_stripe_offset. + * Full OSTs are not considered. The exact order of OSTs is not important and + * varies depending on OST status. The allocation procedure prefers the targets + * with precreated objects ready. The number of stripes needed and stripe + * offset are taken from the object. If that number can not be met, then the + * function returns a failure and then it's the caller's responsibility to + * release the stripes allocated. All the internal structures are protected, + * but no concurrent allocation is allowed on the same objects. + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[out] stripe striping created + * \param[in] flags not used + * \param[in] th transaction handle + * + * \retval 0 on success + * \retval -E2BIG if no enough OSTs are found + * \retval -EINVAL requested offset is invalid + * \retval negative negated errno on error + */ +static int lod_alloc_specific(const struct lu_env *env, struct lod_object *lo, + struct dt_object **stripe, int flags, + struct thandle *th) +{ + struct lod_device *m = lu2lod_dev(lo->ldo_obj.do_lu.lo_dev); + struct obd_statfs *sfs = &lod_env_info(env)->lti_osfs; + struct dt_object *o; + __u32 ost_idx; + unsigned int i, array_idx, ost_count; + int rc, stripe_num = 0; + int speed = 0; + struct pool_desc *pool = NULL; + struct ost_pool *osts; + ENTRY; + + rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr); + if (rc) + GOTO(out, rc); + + if (lo->ldo_pool) + pool = lod_find_pool(m, lo->ldo_pool); + + if (pool != NULL) { + down_read(&pool_tgt_rw_sem(pool)); + osts = &(pool->pool_obds); + } else { + osts = &(m->lod_pool_info); + } + + ost_count = osts->op_count; + +repeat_find: + /* search loi_ost_idx in ost array */ + array_idx = 0; + for (i = 0; i < ost_count; i++) { + if (osts->op_array[i] == lo->ldo_def_stripe_offset) { + array_idx = i; + break; + } + } + if (i == ost_count) { + CERROR("Start index %d not found in pool '%s'\n", + lo->ldo_def_stripe_offset, + lo->ldo_pool ? lo->ldo_pool : ""); + GOTO(out, rc = -EINVAL); + } + + for (i = 0; i < ost_count; + i++, array_idx = (array_idx + 1) % ost_count) { + ost_idx = osts->op_array[array_idx]; + + if (!cfs_bitmap_check(m->lod_ost_bitmap, ost_idx)) + continue; + + /* Fail Check before osc_precreate() is called + so we can only 'fail' single OSC. */ + if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && ost_idx == 0) + continue; + + /* + * do not put >1 objects on a single OST + */ + if (lod_qos_is_ost_used(env, ost_idx, stripe_num)) + continue; + + /* Drop slow OSCs if we can, but not for requested start idx. + * + * This means "if OSC is slow and it is not the requested + * start OST, then it can be skipped, otherwise skip it only + * if it is inactive/recovering/out-of-space." */ + + rc = lod_statfs_and_check(env, m, ost_idx, sfs); + if (rc) { + /* this OSP doesn't feel well */ + continue; + } + + /* + * We expect number of precreated objects in f_ffree at + * the first iteration, skip OSPs with no objects ready + * don't apply this logic to OST specified with stripe_offset + */ + if (i != 0 && sfs->os_fprecreated == 0 && speed == 0) + continue; + + o = lod_qos_declare_object_on(env, m, ost_idx, th); + if (IS_ERR(o)) { + CDEBUG(D_OTHER, "can't declare new object on #%u: %d\n", + ost_idx, (int) PTR_ERR(o)); + continue; + } + + /* + * We've successfuly declared (reserved) an object + */ + lod_qos_ost_in_use(env, stripe_num, ost_idx); + stripe[stripe_num] = o; + stripe_num++; + + /* We have enough stripes */ + if (stripe_num == lo->ldo_stripenr) + GOTO(out, rc = 0); + } + if (speed < 2) { + /* Try again, allowing slower OSCs */ + speed++; + goto repeat_find; + } + + /* If we were passed specific striping params, then a failure to + * meet those requirements is an error, since we can't reallocate + * that memory (it might be part of a larger array or something). + * + * We can only get here if lsm_stripe_count was originally > 1. + */ + CERROR("can't lstripe objid "DFID": have %d want %u\n", + PFID(lu_object_fid(lod2lu_obj(lo))), stripe_num, + lo->ldo_stripenr); + rc = -EFBIG; +out: + if (pool != NULL) { + up_read(&pool_tgt_rw_sem(pool)); + /* put back ref got by lod_find_pool() */ + lod_pool_putref(pool); + } + + RETURN(rc); +} + +/** + * Check whether QoS allocation should be used. + * + * A simple helper to decide when QoS allocation should be used: + * if it's just a single available target or the used space is + * evenly distributed among the targets at the moment, then QoS + * allocation algorithm should not be used. + * + * \param[in] lod LOD device + * + * \retval 0 should not be used + * \retval 1 should be used + */ +static inline int lod_qos_is_usable(struct lod_device *lod) +{ +#ifdef FORCE_QOS + /* to be able to debug QoS code */ + return 1; +#endif + + /* Detect -EAGAIN early, before expensive lock is taken. */ + if (!lod->lod_qos.lq_dirty && lod->lod_qos.lq_same_space) + return 0; + + if (lod->lod_desc.ld_active_tgt_count < 2) + return 0; + + return 1; +} + +/** + * Allocate a striping using an algorithm with weights. + * + * The function allocates OST objects to create a striping. The algorithm + * used is based on weights (currently only using the free space), and it's + * trying to ensure the space is used evenly by OSTs and OSSs. The striping + * configuration (# of stripes, offset, + * pool) is taken from the object and is prepared by the caller. + * If LOV_USES_DEFAULT_STRIPE is not passed and prepared configuration can't + * be met due to too few OSTs, then allocation fails. If the flag is + * passed and less than 75% of the requested number of stripes can be + * allocated, then allocation fails. + * No concurrent allocation is allowed on the object and this must be + * ensured by the caller. All the internal structures are protected by the + * function. + * The algorithm has two steps: find available OSTs and calucate their weights, + * then select the OSTs the weights used as the probability. An OST with a + * higher weight is proportionately more likely to be selected than one with + * a lower weight. + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[out] stripe striping created + * \param[in] flags 0 or LOV_USES_DEFAULT_STRIPE + * \param[in] th transaction handle + * + * \retval 0 on success + * \retval -E2BIG if no enough OSTs are found + * \retval -EINVAL requested offset is invalid + * \retval negative negated errno on error + */ +static int lod_alloc_qos(const struct lu_env *env, struct lod_object *lo, + struct dt_object **stripe, int flags, + struct thandle *th) +{ + struct lod_device *m = lu2lod_dev(lo->ldo_obj.do_lu.lo_dev); + struct obd_statfs *sfs = &lod_env_info(env)->lti_osfs; + struct lod_tgt_desc *ost; + struct dt_object *o; + __u64 total_weight = 0; + unsigned int i; + int rc = 0; + __u32 nfound, good_osts; + __u32 stripe_cnt = lo->ldo_stripenr; + __u32 stripe_cnt_min; + struct pool_desc *pool = NULL; + struct ost_pool *osts; + ENTRY; + + stripe_cnt_min = min_stripe_count(stripe_cnt, flags); + if (stripe_cnt_min < 1) + RETURN(-EINVAL); + + if (lo->ldo_pool) + pool = lod_find_pool(m, lo->ldo_pool); + + if (pool != NULL) { + down_read(&pool_tgt_rw_sem(pool)); + osts = &(pool->pool_obds); + } else { + osts = &(m->lod_pool_info); + } + + /* Detect -EAGAIN early, before expensive lock is taken. */ + if (!lod_qos_is_usable(m)) + GOTO(out_nolock, rc = -EAGAIN); + + /* Do actual allocation, use write lock here. */ + down_write(&m->lod_qos.lq_rw_sem); + + /* + * Check again, while we were sleeping on @lq_rw_sem things could + * change. + */ + if (!lod_qos_is_usable(m)) + GOTO(out, rc = -EAGAIN); + + rc = lod_qos_calc_ppo(m); + if (rc) + GOTO(out, rc); + + rc = lod_qos_ost_in_use_clear(env, lo->ldo_stripenr); + if (rc) + GOTO(out, rc); + + good_osts = 0; + /* Find all the OSTs that are valid stripe candidates */ + for (i = 0; i < osts->op_count; i++) { + if (!cfs_bitmap_check(m->lod_ost_bitmap, osts->op_array[i])) + continue; + + rc = lod_statfs_and_check(env, m, osts->op_array[i], sfs); + if (rc) { + /* this OSP doesn't feel well */ + continue; + } + + /* + * skip full devices + */ + if (lod_qos_dev_is_full(sfs)) + continue; + + /* Fail Check before osc_precreate() is called + so we can only 'fail' single OSC. */ + if (OBD_FAIL_CHECK(OBD_FAIL_MDS_OSC_PRECREATE) && + osts->op_array[i] == 0) + continue; + + ost = OST_TGT(m,osts->op_array[i]); + ost->ltd_qos.ltq_usable = 1; + lod_qos_calc_weight(m, osts->op_array[i]); + total_weight += ost->ltd_qos.ltq_weight; + + good_osts++; + } + + QOS_DEBUG("found %d good osts\n", good_osts); + + if (good_osts < stripe_cnt_min) + GOTO(out, rc = -EAGAIN); + + /* We have enough osts */ + if (good_osts < stripe_cnt) + stripe_cnt = good_osts; + + /* Find enough OSTs with weighted random allocation. */ + nfound = 0; + while (nfound < stripe_cnt) { + __u64 rand, cur_weight; + + cur_weight = 0; + rc = -ENOSPC; + + if (total_weight) { +#if BITS_PER_LONG == 32 + rand = cfs_rand() % (unsigned)total_weight; + /* If total_weight > 32-bit, first generate the high + * 32 bits of the random number, then add in the low + * 32 bits (truncated to the upper limit, if needed) */ + if (total_weight > 0xffffffffULL) + rand = (__u64)(cfs_rand() % + (unsigned)(total_weight >> 32)) << 32; + else + rand = 0; + + if (rand == (total_weight & 0xffffffff00000000ULL)) + rand |= cfs_rand() % (unsigned)total_weight; + else + rand |= cfs_rand(); + +#else + rand = ((__u64)cfs_rand() << 32 | cfs_rand()) % + total_weight; +#endif + } else { + rand = 0; + } + + /* On average, this will hit larger-weighted osts more often. + 0-weight osts will always get used last (only when rand=0) */ + for (i = 0; i < osts->op_count; i++) { + __u32 idx = osts->op_array[i]; + + if (!cfs_bitmap_check(m->lod_ost_bitmap, idx)) + continue; + + ost = OST_TGT(m,idx); + + if (!ost->ltd_qos.ltq_usable) + continue; + + cur_weight += ost->ltd_qos.ltq_weight; + QOS_DEBUG("stripe_cnt=%d nfound=%d cur_weight="LPU64 + " rand="LPU64" total_weight="LPU64"\n", + stripe_cnt, nfound, cur_weight, rand, + total_weight); + + if (cur_weight < rand) + continue; + + QOS_DEBUG("stripe=%d to idx=%d\n", nfound, idx); + + /* + * do not put >1 objects on a single OST + */ + if (lod_qos_is_ost_used(env, idx, nfound)) + continue; + lod_qos_ost_in_use(env, nfound, idx); + + o = lod_qos_declare_object_on(env, m, idx, th); + if (IS_ERR(o)) { + QOS_DEBUG("can't declare object on #%u: %d\n", + idx, (int) PTR_ERR(o)); + continue; + } + stripe[nfound++] = o; + lod_qos_used(m, osts, idx, &total_weight); + rc = 0; + break; + } + + if (rc) { + /* no OST found on this iteration, give up */ + break; + } + } + + if (unlikely(nfound != stripe_cnt)) { + /* + * when the decision to use weighted algorithm was made + * we had enough appropriate OSPs, but this state can + * change anytime (no space on OST, broken connection, etc) + * so it's possible OSP won't be able to provide us with + * an object due to just changed state + */ + LCONSOLE_INFO("wanted %d, found %d\n", stripe_cnt, nfound); + for (i = 0; i < nfound; i++) { + LASSERT(stripe[i] != NULL); + lu_object_put(env, &stripe[i]->do_lu); + stripe[i] = NULL; + } + + /* makes sense to rebalance next time */ + m->lod_qos.lq_dirty = 1; + m->lod_qos.lq_same_space = 0; + + rc = -EAGAIN; + } + +out: + up_write(&m->lod_qos.lq_rw_sem); + +out_nolock: + if (pool != NULL) { + up_read(&pool_tgt_rw_sem(pool)); + /* put back ref got by lod_find_pool() */ + lod_pool_putref(pool); + } + + RETURN(rc); +} + +/** + * Find largest stripe count the caller can use. + * + * Find the maximal possible stripe count not greater than \a stripe_count. + * Sometimes suggested stripecount can't be reached for a number of reasons: + * lack of enough active OSTs or the backend does not support EAs that large. + * If the passed one is 0, then the filesystem's default one is used. + * + * \param[in] lod LOD device + * \param[in] magic the format if striping + * \param[in] stripe_count count the caller would like to use + * + * \retval the maximum usable stripe count + */ +static __u16 lod_get_stripecnt(struct lod_device *lod, __u32 magic, + __u16 stripe_count) +{ + __u32 max_stripes = LOV_MAX_STRIPE_COUNT_OLD; + + if (!stripe_count) + stripe_count = lod->lod_desc.ld_default_stripe_count; + if (stripe_count > lod->lod_desc.ld_active_tgt_count) + stripe_count = lod->lod_desc.ld_active_tgt_count; + if (!stripe_count) + stripe_count = 1; + + /* stripe count is based on whether OSD can handle larger EA sizes */ + if (lod->lod_osd_max_easize > 0) + max_stripes = lov_mds_md_max_stripe_count( + lod->lod_osd_max_easize, magic); + + return (stripe_count < max_stripes) ? stripe_count : max_stripes; +} + +/** + * Create in-core respresentation for a fully-defined striping + * + * When the caller passes a fully-defined striping (i.e. everything including + * OST object FIDs are defined), then we still need to instantiate LU-cache + * with the objects representing the stripes defined. This function completes + * that task. + * + * \param[in] env execution environment for this thread + * \param[in] mo LOD object + * \param[in] buf buffer containing the striping + * + * \retval 0 on success + * \retval negative negated errno on error + */ +static int lod_use_defined_striping(const struct lu_env *env, + struct lod_object *mo, + const struct lu_buf *buf) +{ + struct lov_mds_md_v1 *v1 = buf->lb_buf; + struct lov_mds_md_v3 *v3 = buf->lb_buf; + struct lov_ost_data_v1 *objs; + __u32 magic; + int rc = 0; + ENTRY; + + magic = le32_to_cpu(v1->lmm_magic); + if (magic == LOV_MAGIC_V1_DEF) { + magic = LOV_MAGIC_V1; + objs = &v1->lmm_objects[0]; + } else if (magic == LOV_MAGIC_V3_DEF) { + magic = LOV_MAGIC_V3; + objs = &v3->lmm_objects[0]; + lod_object_set_pool(mo, v3->lmm_pool_name); + } else { + GOTO(out, rc = -EINVAL); + } + + mo->ldo_pattern = le32_to_cpu(v1->lmm_pattern); + mo->ldo_stripe_size = le32_to_cpu(v1->lmm_stripe_size); + mo->ldo_stripenr = le16_to_cpu(v1->lmm_stripe_count); + mo->ldo_layout_gen = le16_to_cpu(v1->lmm_layout_gen); + + /* fixup for released file before object initialization */ + if (mo->ldo_pattern & LOV_PATTERN_F_RELEASED) { + mo->ldo_released_stripenr = mo->ldo_stripenr; + mo->ldo_stripenr = 0; + } + + LASSERT(buf->lb_len >= lov_mds_md_size(mo->ldo_stripenr, magic)); + + if (mo->ldo_stripenr > 0) + rc = lod_initialize_objects(env, mo, objs); + +out: + RETURN(rc); +} + +/** + * Parse suggested striping configuration. + * + * The caller gets a suggested striping configuration from a number of sources + * including per-directory default and applications. Then it needs to verify + * the suggested striping is valid, apply missing bits and store the resulting + * configuration in the object to be used by the allocator later. Must not be + * called concurrently against the same object. It's OK to provide a + * fully-defined striping. + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[in] buf buffer containing the striping + * + * \retval 0 on success + * \retval negative negated errno on error + */ +static int lod_qos_parse_config(const struct lu_env *env, + struct lod_object *lo, + const struct lu_buf *buf) +{ + struct lod_device *d = lu2lod_dev(lod2lu_obj(lo)->lo_dev); + struct lov_user_md_v1 *v1 = NULL; + struct lov_user_md_v3 *v3 = NULL; + char *pool_name = NULL; + __u32 magic; + int rc; + unsigned int size; + ENTRY; + + if (buf == NULL || buf->lb_buf == NULL || buf->lb_len == 0) + RETURN(0); + + v3 = buf->lb_buf; + v1 = buf->lb_buf; + magic = v1->lmm_magic; + + if (unlikely(magic == LOV_MAGIC_V1_DEF || magic == LOV_MAGIC_V3_DEF)) { + /* try to use as fully defined striping */ + rc = lod_use_defined_striping(env, lo, buf); + RETURN(rc); + } + + switch (magic) { + case __swab32(LOV_USER_MAGIC_V1): + lustre_swab_lov_user_md_v1(v1); + magic = v1->lmm_magic; + /* fall through */ + case LOV_USER_MAGIC_V1: + size = sizeof(*v1); + break; + + case __swab32(LOV_USER_MAGIC_V3): + lustre_swab_lov_user_md_v3(v3); + magic = v3->lmm_magic; + /* fall through */ + case LOV_USER_MAGIC_V3: + size = sizeof(*v3); + pool_name = v3->lmm_pool_name; + break; + + case __swab32(LOV_USER_MAGIC_SPECIFIC): + lustre_swab_lov_user_md_v3(v3); + lustre_swab_lov_user_md_objects(v3->lmm_objects, + v3->lmm_stripe_count); + magic = v3->lmm_magic; + /* fall through */ + case LOV_USER_MAGIC_SPECIFIC: + if (v3->lmm_stripe_offset == LOV_OFFSET_DEFAULT) + v3->lmm_stripe_offset = v3->lmm_objects[0].l_ost_idx; + if (v3->lmm_pool_name[0] != '\0') + pool_name = v3->lmm_pool_name; + size = lov_user_md_size(v3->lmm_stripe_count, + LOV_USER_MAGIC_SPECIFIC); + break; + + default: + CERROR("%s: unrecognized magic %X\n", + lod2obd(d)->obd_name, magic); + RETURN(-EINVAL); + } + + if (unlikely(buf->lb_len < size)) { + CERROR("%s: wrong size: %zd, expect: %u\n", + lod2obd(d)->obd_name, buf->lb_len, size); + RETURN(-EINVAL); + } + + lustre_print_user_md(D_OTHER, v1, "parse config"); + + v1->lmm_magic = magic; + if (v1->lmm_pattern == 0) + v1->lmm_pattern = LOV_PATTERN_RAID0; + if (lov_pattern(v1->lmm_pattern) != LOV_PATTERN_RAID0) { + CERROR("%s: invalid pattern: %x\n", + lod2obd(d)->obd_name, v1->lmm_pattern); + RETURN(-EINVAL); + } + lo->ldo_pattern = v1->lmm_pattern; + + if (v1->lmm_stripe_size > 0) + lo->ldo_stripe_size = v1->lmm_stripe_size; + + if (lo->ldo_stripe_size & (LOV_MIN_STRIPE_SIZE - 1)) + lo->ldo_stripe_size = LOV_MIN_STRIPE_SIZE; + + if (v1->lmm_stripe_count > 0) + lo->ldo_stripenr = v1->lmm_stripe_count; + + lo->ldo_def_stripe_offset = v1->lmm_stripe_offset; + + lod_object_set_pool(lo, NULL); + if (pool_name != NULL) { + struct pool_desc *pool; + + /* In the function below, .hs_keycmp resolves to + * pool_hashkey_keycmp() */ + /* coverity[overrun-buffer-val] */ + pool = lod_find_pool(d, pool_name); + if (pool != NULL) { + if (lo->ldo_def_stripe_offset != LOV_OFFSET_DEFAULT) { + rc = lod_check_index_in_pool( + lo->ldo_def_stripe_offset, pool); + if (rc < 0) { + lod_pool_putref(pool); + CERROR("%s: invalid offset, %u\n", + lod2obd(d)->obd_name, + lo->ldo_def_stripe_offset); + RETURN(-EINVAL); + } + } + + if (lo->ldo_stripenr > pool_tgt_count(pool)) + lo->ldo_stripenr = pool_tgt_count(pool); + + lod_pool_putref(pool); + } + + lod_object_set_pool(lo, pool_name); + } + + /* fixup for released file */ + if (lo->ldo_pattern & LOV_PATTERN_F_RELEASED) { + lo->ldo_released_stripenr = lo->ldo_stripenr; + lo->ldo_stripenr = 0; + } + + RETURN(0); +} + +/** + * Create a striping for an obejct. + * + * The function creates a new striping for the object. A buffer containing + * configuration hints can be provided optionally. The function tries QoS + * algorithm first unless free space is distributed evenly among OSTs, but + * by default RR algorithm is preferred due to internal concurrency (QoS is + * serialized). The caller must ensure no concurrent calls to the function + * are made against the same object. + * + * \param[in] env execution environment for this thread + * \param[in] lo LOD object + * \param[in] attr attributes OST objects will be declared with + * \param[in] buf suggested striping configuration or NULL + * \param[in] th transaction handle + * + * \retval 0 on success + * \retval negative negated errno on error + */ +int lod_qos_prep_create(const struct lu_env *env, struct lod_object *lo, + struct lu_attr *attr, const struct lu_buf *buf, + struct thandle *th) +{ + struct lod_device *d = lu2lod_dev(lod2lu_obj(lo)->lo_dev); + struct dt_object **stripe; + int stripe_len; + int flag = LOV_USES_ASSIGNED_STRIPE; + int i, rc; + ENTRY; + + LASSERT(lo); + + /* no OST available */ + /* XXX: should we be waiting a bit to prevent failures during + * cluster initialization? */ + if (d->lod_ostnr == 0) + GOTO(out, rc = -EIO); + + /* + * by this time, the object's ldo_stripenr and ldo_stripe_size + * contain default value for striping: taken from the parent + * or from filesystem defaults + * + * in case the caller is passing lovea with new striping config, + * we may need to parse lovea and apply new configuration + */ + rc = lod_qos_parse_config(env, lo, buf); + if (rc) + GOTO(out, rc); + + /* A released file is being created */ + if (lo->ldo_stripenr == 0) + GOTO(out, rc = 0); + + if (likely(lo->ldo_stripe == NULL)) { + struct lov_user_md *lum = NULL; + + /* + * no striping has been created so far + */ + LASSERT(lo->ldo_stripenr > 0); + /* + * statfs and check OST targets now, since ld_active_tgt_count + * could be changed if some OSTs are [de]activated manually. + */ + lod_qos_statfs_update(env, d); + lo->ldo_stripenr = lod_get_stripecnt(d, LOV_MAGIC, + lo->ldo_stripenr); + + stripe_len = lo->ldo_stripenr; + OBD_ALLOC(stripe, sizeof(stripe[0]) * stripe_len); + if (stripe == NULL) + GOTO(out, rc = -ENOMEM); + + lod_getref(&d->lod_ost_descs); + /* XXX: support for non-0 files w/o objects */ + CDEBUG(D_OTHER, "tgt_count %d stripenr %d\n", + d->lod_desc.ld_tgt_count, stripe_len); + + if (buf != NULL && buf->lb_buf != NULL) + lum = buf->lb_buf; + + if (lum != NULL && lum->lmm_magic == LOV_USER_MAGIC_SPECIFIC) { + rc = lod_alloc_ost_list(env, lo, stripe, lum, th); + } else if (lo->ldo_def_stripe_offset == LOV_OFFSET_DEFAULT) { + rc = lod_alloc_qos(env, lo, stripe, flag, th); + if (rc == -EAGAIN) + rc = lod_alloc_rr(env, lo, stripe, flag, th); + } else { + rc = lod_alloc_specific(env, lo, stripe, flag, th); + } + lod_putref(d, &d->lod_ost_descs); + + if (rc < 0) { + for (i = 0; i < stripe_len; i++) + if (stripe[i] != NULL) + lu_object_put(env, &stripe[i]->do_lu); + + OBD_FREE(stripe, sizeof(stripe[0]) * stripe_len); + lo->ldo_stripenr = 0; + } else { + lo->ldo_stripe = stripe; + lo->ldo_stripes_allocated = stripe_len; + } + } else { + /* + * lod_qos_parse_config() found supplied buf as a predefined + * striping (not a hint), so it allocated all the object + * now we need to create them + */ + for (i = 0; i < lo->ldo_stripenr; i++) { + struct dt_object *o; + + o = lo->ldo_stripe[i]; + LASSERT(o); + + rc = lod_sub_object_declare_create(env, o, attr, NULL, + NULL, th); + if (rc < 0) { + CERROR("can't declare create: %d\n", rc); + break; + } + } + } + +out: RETURN(rc); }