* 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
* Copyright 2009 Sun Microsystems, Inc. All rights reserved
* Use is subject to license terms.
*
- * Copyright (c) 2011, 2012, Whamcloud, Inc.
+ * Copyright (c) 2012, 2015, Intel Corporation.
*/
/*
* This file is part of Lustre, http://www.lustre.org/
*
* lustre/lod/lod_qos.c
*
+ * Implementation of different allocation algorithm used
+ * to distribute objects and data among OSTs.
*/
#define DEBUG_SUBSYSTEM S_LOV
+#include <asm/div64.h>
#include <libcfs/libcfs.h>
-#include <obd_class.h>
-#include <obd_lov.h>
#include <lustre/lustre_idl.h>
+#include <lustre_swab.h>
+#include <obd_class.h>
+
#include "lod_internal.h"
/*
#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++;
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++;
/* 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);
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);
}
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 == 0 && ((sfs->os_state & OS_STATE_ENOSPC) ||
+ (sfs->os_state & OS_STATE_ENOINO && sfs->os_fprecreated == 0)))
+ RETURN(-ENOSPC);
+
+ 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_lock);
+ if (ost->ltd_active) {
+ ost->ltd_active = 0;
+ if (rc == -ENOTCONN)
+ ost->ltd_connecting = 1;
+
+ 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_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_lock);
+ if (ost->ltd_active == 0) {
+ ost->ltd_active = 1;
+ ost->ltd_connecting = 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 active\n",
+ ost->ltd_exp->exp_obd->obd_name);
+ }
+ spin_unlock(&d->lod_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=%llu"
+ " ostppo=%llu ostp=%llu ossppo=%llu"
+ " ossp=%llu wt=%llu\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);
+}
+
+void lod_qos_rr_init(struct lod_qos_rr *lqr)
+{
+ spin_lock_init(&lqr->lqr_alloc);
+ lqr->lqr_dirty = 1;
+}
+
+
+#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
+
+/**
+ * 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;
+}
+
+static int lod_check_and_reserve_ost(const struct lu_env *env,
+ struct lod_device *m,
+ struct obd_statfs *sfs, __u32 ost_idx,
+ __u32 speed, __u32 *s_idx,
+ struct dt_object **stripe,
+ struct thandle *th)
+{
+ struct dt_object *o;
+ __u32 stripe_idx = *s_idx;
+ int rc;
+
+ rc = lod_statfs_and_check(env, m, ost_idx, sfs);
+ if (rc) {
+ /* this OSP doesn't feel well */
+ goto out_return;
+ }
+
+ /*
+ * 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);
+ goto out_return;
+ }
+
+ /*
+ * 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);
+ goto out_return;
+ }
+
+ /*
+ * do not put >1 objects on a single OST
+ */
+ if (lod_qos_is_ost_used(env, ost_idx, stripe_idx))
+ goto out_return;
+
+ 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);
+ goto out_return;
+ }
+
+ /*
+ * We've successfully declared (reserved) an object
+ */
+ lod_qos_ost_in_use(env, stripe_idx, ost_idx);
+ stripe[stripe_idx] = o;
+ OBD_FAIL_TIMEOUT(OBD_FAIL_MDS_LOV_CREATE_RACE, 2);
+ stripe_idx++;
+ *s_idx = stripe_idx;
+
+out_return:
+ return rc;
+}
+
+/**
+ * Allocate a striping using round-robin algorithm.
+ *
+ * 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;
+ unsigned int i, array_idx;
+ int rc;
+ __u32 ost_start_idx_temp;
+ int speed = 0;
+ int ost_connecting = 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);
+
+ down_read(&m->lod_qos.lq_rw_sem);
+ spin_lock(&lqr->lqr_alloc);
+ 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;
+ }
+ ost_start_idx_temp = lqr->lqr_start_idx;
+
+repeat_find:
+
+ QOS_DEBUG("pool '%s' want %d startidx %d startcnt %d offset %d "
+ "active %d count %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);
+
+ for (i = 0; i < osts->op_count && stripe_idx < lo->ldo_stripenr; i++) {
+ array_idx = (lqr->lqr_start_idx + lqr->lqr_offset_idx) %
+ 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;
+
+ spin_unlock(&lqr->lqr_alloc);
+ rc = lod_check_and_reserve_ost(env, m, sfs, ost_idx, speed,
+ &stripe_idx, stripe, th);
+ spin_lock(&lqr->lqr_alloc);
+
+ if (rc != 0 && OST_TGT(m, ost_idx)->ltd_connecting)
+ ost_connecting = 1;
+ }
+ if ((speed < 2) && (stripe_idx < stripe_cnt_min)) {
+ /* Try again, allowing slower OSCs */
+ speed++;
+ lqr->lqr_start_idx = ost_start_idx_temp;
+
+ ost_connecting = 0;
+ goto repeat_find;
+ }
+
+ spin_unlock(&lqr->lqr_alloc);
+ 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 */
+ if (ost_connecting)
+ rc = -EINPROGRESS;
+ else
+ 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_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_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 successfully 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 layout starting from OST index in lo->ldo_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 cannot be met, then the
+ * function returns an error 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 -ENOSPC if no OST objects are available at all
+ * \retval -EFBIG if not enough OST objects are found
+ * \retval -EINVAL requested offset is invalid
+ * \retval negative errno on failure
+ */
+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_stripe_offset) {
+ array_idx = i;
+ break;
+ }
+ }
+ if (i == ost_count) {
+ CERROR("Start index %d not found in pool '%s'\n",
+ lo->ldo_stripe_offset, 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 successfully 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).
+ */
+ CERROR("can't lstripe objid "DFID": have %d want %u\n",
+ PFID(lu_object_fid(lod2lu_obj(lo))), stripe_num,
+ lo->ldo_stripenr);
+ rc = stripe_num == 0 ? -ENOSPC : -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
+ * fewer than 3/4 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 calculate their
+ * weights, then select the OSTs with their 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 -EAGAIN not enough OSTs are found for specified stripe count
+ * \retval -EINVAL requested OST index is invalid
+ * \retval negative errno on failure
+ */
+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 *lod = 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;
+ __u32 nfound, good_osts;
+ __u32 stripe_cnt = lo->ldo_stripenr;
+ __u32 stripe_cnt_min;
+ struct pool_desc *pool = NULL;
+ struct ost_pool *osts;
+ unsigned int i;
+ int rc = 0;
+ 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(lod, lo->ldo_pool);
+
+ if (pool != NULL) {
+ down_read(&pool_tgt_rw_sem(pool));
+ osts = &(pool->pool_obds);
+ } else {
+ osts = &(lod->lod_pool_info);
+ }
+
+ /* Detect -EAGAIN early, before expensive lock is taken. */
+ if (!lod_qos_is_usable(lod))
+ GOTO(out_nolock, rc = -EAGAIN);
+
+ /* Do actual allocation, use write lock here. */
+ down_write(&lod->lod_qos.lq_rw_sem);
+
+ /*
+ * Check again, while we were sleeping on @lq_rw_sem things could
+ * change.
+ */
+ if (!lod_qos_is_usable(lod))
+ GOTO(out, rc = -EAGAIN);
+
+ rc = lod_qos_calc_ppo(lod);
+ 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(lod->lod_ost_bitmap, osts->op_array[i]))
+ continue;
+
+ ost = OST_TGT(lod, osts->op_array[i]);
+ ost->ltd_qos.ltq_usable = 0;
+
+ rc = lod_statfs_and_check(env, lod, osts->op_array[i], sfs);
+ if (rc) {
+ /* this OSP doesn't feel well */
+ continue;
+ }
+
+ if (sfs->os_state & OS_STATE_DEGRADED)
+ 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->ltd_qos.ltq_usable = 1;
+ lod_qos_calc_weight(lod, 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(lod->lod_ost_bitmap, idx))
+ continue;
+
+ ost = OST_TGT(lod, idx);
+
+ if (!ost->ltd_qos.ltq_usable)
+ continue;
+
+ cur_weight += ost->ltd_qos.ltq_weight;
+ QOS_DEBUG("stripe_cnt=%d nfound=%d cur_weight=%llu"
+ " rand=%llu total_weight=%llu\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, lod, 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(lod, 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
+ */
+ QOS_DEBUG("%s: wanted %d objects, found only %d\n",
+ lod2obd(lod)->obd_name, 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 */
+ lod->lod_qos.lq_dirty = 1;
+ lod->lod_qos.lq_same_space = 0;
+
+ rc = -EAGAIN;
+ }
+
+out:
+ up_write(&lod->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_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_stripe_offset != LOV_OFFSET_DEFAULT) {
+ rc = lod_check_index_in_pool(
+ lo->ldo_stripe_offset, pool);
+ if (rc < 0) {
+ lod_pool_putref(pool);
+ CERROR("%s: invalid offset, %u\n",
+ lod2obd(d)->obd_name,
+ lo->ldo_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_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);
}
git://git.whamcloud.com / fs / lustre-release.git / blobdiff