[lustre-devel] [PATCH 486/622] lustre: lmv: share object alloc QoS code with LMV
James Simmons
jsimmons at infradead.org
Thu Feb 27 13:15:54 PST 2020
From: Lai Siyao <lai.siyao at whamcloud.com>
Move object alloc QoS code to obdclass, so that LMV and LOD
can share the same code.
WC-bug-id: https://jira.whamcloud.com/browse/LU-11213
Lustre-commit: d3090bb2b486 ("LU-11213 lod: share object alloc QoS code with LMV")
Signed-off-by: Lai Siyao <lai.siyao at whamcloud.com>
Reviewed-on: https://review.whamcloud.com/35219
Reviewed-by: Hongchao Zhang <hongchao at whamcloud.com>
Reviewed-by: Andreas Dilger <adilger at whamcloud.com>
Reviewed-by: Oleg Drokin <green at whamcloud.com>
Signed-off-by: James Simmons <jsimmons at infradead.org>
---
fs/lustre/include/lu_object.h | 7 +
fs/lustre/lmv/Makefile | 2 +-
fs/lustre/lmv/lmv_internal.h | 4 -
fs/lustre/lmv/lmv_obd.c | 87 +++++++++
fs/lustre/lmv/lmv_qos.c | 411 ------------------------------------------
fs/lustre/obdclass/lu_qos.c | 303 +++++++++++++++++++++++++++++++
6 files changed, 398 insertions(+), 416 deletions(-)
delete mode 100644 fs/lustre/lmv/lmv_qos.c
diff --git a/fs/lustre/include/lu_object.h b/fs/lustre/include/lu_object.h
index c30c06d..eaf20ea 100644
--- a/fs/lustre/include/lu_object.h
+++ b/fs/lustre/include/lu_object.h
@@ -1442,6 +1442,13 @@ struct lu_qos {
void lu_qos_rr_init(struct lu_qos_rr *lqr);
int lqos_add_tgt(struct lu_qos *qos, struct lu_tgt_desc *ltd);
int lqos_del_tgt(struct lu_qos *qos, struct lu_tgt_desc *ltd);
+bool lqos_is_usable(struct lu_qos *qos, u32 active_tgt_nr);
+int lqos_calc_penalties(struct lu_qos *qos, struct lu_tgt_descs *ltd,
+ u32 active_tgt_nr, u32 maxage, bool is_mdt);
+void lqos_calc_weight(struct lu_tgt_desc *tgt);
+int lqos_recalc_weight(struct lu_qos *qos, struct lu_tgt_descs *ltd,
+ struct lu_tgt_desc *tgt, u32 active_tgt_nr,
+ u64 *total_wt);
u64 lu_prandom_u64_max(u64 ep_ro);
int lu_tgt_descs_init(struct lu_tgt_descs *ltd);
diff --git a/fs/lustre/lmv/Makefile b/fs/lustre/lmv/Makefile
index 6f9a19c..ad470bf 100644
--- a/fs/lustre/lmv/Makefile
+++ b/fs/lustre/lmv/Makefile
@@ -1,4 +1,4 @@
ccflags-y += -I$(srctree)/$(src)/../include
obj-$(CONFIG_LUSTRE_FS) += lmv.o
-lmv-y := lmv_obd.o lmv_intent.o lmv_fld.o lproc_lmv.o lmv_qos.o
+lmv-y := lmv_obd.o lmv_intent.o lmv_fld.o lproc_lmv.o
diff --git a/fs/lustre/lmv/lmv_internal.h b/fs/lustre/lmv/lmv_internal.h
index e0c3ba0..d95fa3f 100644
--- a/fs/lustre/lmv/lmv_internal.h
+++ b/fs/lustre/lmv/lmv_internal.h
@@ -218,10 +218,6 @@ static inline bool lmv_dir_retry_check_update(struct md_op_data *op_data)
struct lmv_tgt_desc *lmv_locate_tgt(struct lmv_obd *lmv,
struct md_op_data *op_data);
-/* lmv_qos.c */
-struct lu_tgt_desc *lmv_locate_tgt_qos(struct lmv_obd *lmv, u32 *mdt);
-struct lu_tgt_desc *lmv_locate_tgt_rr(struct lmv_obd *lmv, u32 *mdt);
-
/* lproc_lmv.c */
int lmv_tunables_init(struct obd_device *obd);
diff --git a/fs/lustre/lmv/lmv_obd.c b/fs/lustre/lmv/lmv_obd.c
index 8d682b4..2959b18 100644
--- a/fs/lustre/lmv/lmv_obd.c
+++ b/fs/lustre/lmv/lmv_obd.c
@@ -1518,6 +1518,93 @@ static int lmv_close(struct obd_export *exp, struct md_op_data *op_data,
return md_close(tgt->ltd_exp, op_data, mod, request);
}
+static struct lu_tgt_desc *lmv_locate_tgt_qos(struct lmv_obd *lmv, u32 *mdt)
+{
+ struct lu_tgt_desc *tgt;
+ u64 total_weight = 0;
+ u64 cur_weight = 0;
+ u64 rand;
+ int rc;
+
+ if (!lqos_is_usable(&lmv->lmv_qos, lmv->desc.ld_active_tgt_count))
+ return ERR_PTR(-EAGAIN);
+
+ down_write(&lmv->lmv_qos.lq_rw_sem);
+
+ if (!lqos_is_usable(&lmv->lmv_qos, lmv->desc.ld_active_tgt_count)) {
+ tgt = ERR_PTR(-EAGAIN);
+ goto unlock;
+ }
+
+ rc = lqos_calc_penalties(&lmv->lmv_qos, &lmv->lmv_mdt_descs,
+ lmv->desc.ld_active_tgt_count,
+ lmv->desc.ld_qos_maxage, true);
+ if (rc) {
+ tgt = ERR_PTR(rc);
+ goto unlock;
+ }
+
+ lmv_foreach_tgt(lmv, tgt) {
+ tgt->ltd_qos.ltq_usable = 0;
+ if (!tgt->ltd_exp || !tgt->ltd_active)
+ continue;
+
+ tgt->ltd_qos.ltq_usable = 1;
+ lqos_calc_weight(tgt);
+ total_weight += tgt->ltd_qos.ltq_weight;
+ }
+
+ rand = lu_prandom_u64_max(total_weight);
+
+ lmv_foreach_connected_tgt(lmv, tgt) {
+ if (!tgt->ltd_qos.ltq_usable)
+ continue;
+
+ cur_weight += tgt->ltd_qos.ltq_weight;
+ if (cur_weight < rand)
+ continue;
+
+ *mdt = tgt->ltd_index;
+ lqos_recalc_weight(&lmv->lmv_qos, &lmv->lmv_mdt_descs, tgt,
+ lmv->desc.ld_active_tgt_count,
+ &total_weight);
+ rc = 0;
+ goto unlock;
+ }
+
+ /* no proper target found */
+ tgt = ERR_PTR(-EAGAIN);
+ goto unlock;
+unlock:
+ up_write(&lmv->lmv_qos.lq_rw_sem);
+
+ return tgt;
+}
+
+static struct lu_tgt_desc *lmv_locate_tgt_rr(struct lmv_obd *lmv, u32 *mdt)
+{
+ struct lu_tgt_desc *tgt;
+ int i;
+ int index;
+
+ spin_lock(&lmv->lmv_qos.lq_rr.lqr_alloc);
+ for (i = 0; i < lmv->desc.ld_tgt_count; i++) {
+ index = (i + lmv->lmv_qos_rr_index) % lmv->desc.ld_tgt_count;
+ tgt = lmv_tgt(lmv, index);
+ if (!tgt || !tgt->ltd_exp || !tgt->ltd_active)
+ continue;
+
+ *mdt = tgt->ltd_index;
+ lmv->lmv_qos_rr_index = (*mdt + 1) % lmv->desc.ld_tgt_count;
+ spin_unlock(&lmv->lmv_qos.lq_rr.lqr_alloc);
+
+ return tgt;
+ }
+ spin_unlock(&lmv->lmv_qos.lq_rr.lqr_alloc);
+
+ return ERR_PTR(-ENODEV);
+}
+
static struct lmv_tgt_desc *
lmv_locate_tgt_by_name(struct lmv_obd *lmv, struct lmv_stripe_md *lsm,
const char *name, int namelen, struct lu_fid *fid,
diff --git a/fs/lustre/lmv/lmv_qos.c b/fs/lustre/lmv/lmv_qos.c
deleted file mode 100644
index 0bee7c0..0000000
--- a/fs/lustre/lmv/lmv_qos.c
+++ /dev/null
@@ -1,411 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * GPL HEADER START
- *
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * 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 LICENSE file that accompanied this code).
- *
- * You should have received a copy of the GNU General Public License
- * version 2 along with this program; If not, see
- * http://www.gnu.org/licenses/gpl-2.0.html
- *
- * GPL HEADER END
- */
-/*
- * This file is part of Lustre, http://www.lustre.org/
- *
- * lustre/lmv/lmv_qos.c
- *
- * LMV QoS.
- * These are the only exported functions, they provide some generic
- * infrastructure for object allocation QoS
- *
- */
-
-#define DEBUG_SUBSYSTEM S_LMV
-
-#include <asm/div64.h>
-#include <uapi/linux/lustre/lustre_idl.h>
-#include <lustre_swab.h>
-#include <obd_class.h>
-
-#include "lmv_internal.h"
-
-static inline u64 tgt_statfs_bavail(struct lu_tgt_desc *tgt)
-{
- struct obd_statfs *statfs = &tgt->ltd_statfs;
-
- return statfs->os_bavail * statfs->os_bsize;
-}
-
-static inline u64 tgt_statfs_iavail(struct lu_tgt_desc *tgt)
-{
- return tgt->ltd_statfs.os_ffree;
-}
-
-/**
- * Calculate penalties per-tgt and per-server
- *
- * Re-calculate penalties when the configuration changes, active targets
- * change and after statfs refresh (all these are reflected by lq_dirty flag).
- * On every MDT and MDS: 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 MDS/MDTs under light load.
- * See lmv_qos_calc_weight() for how penalties are factored into the weight.
- *
- * @lmv LMV device
- *
- * Return: 0 on success
- * -EAGAIN if the number of MDTs isn't enough or all
- * MDT spaces are almost the same
- */
-static int lmv_qos_calc_ppts(struct lmv_obd *lmv)
-{
- struct lu_qos *qos = &lmv->lmv_qos;
- struct lu_tgt_desc *tgt;
- struct lu_svr_qos *svr;
- u64 ba_max, ba_min, ba;
- u64 ia_max, ia_min, ia;
- u32 num_active;
- int prio_wide;
- time64_t now, age;
- u32 maxage = lmv->desc.ld_qos_maxage;
- int rc = 0;
-
-
- if (!qos->lq_dirty)
- goto out;
-
- num_active = lmv->desc.ld_active_tgt_count;
- if (num_active < 2) {
- rc = -EAGAIN;
- goto out;
- }
-
- /* find bavail on each server */
- list_for_each_entry(svr, &qos->lq_svr_list, lsq_svr_list) {
- svr->lsq_bavail = 0;
- svr->lsq_iavail = 0;
- }
- qos->lq_active_svr_count = 0;
-
- /*
- * How badly user wants to select targets "widely" (not recently chosen
- * and not on recent MDS's). As opposed to "freely" (free space avail.)
- * 0-256
- */
- prio_wide = 256 - qos->lq_prio_free;
-
- ba_min = (u64)(-1);
- ba_max = 0;
- ia_min = (u64)(-1);
- ia_max = 0;
- now = ktime_get_real_seconds();
-
- /* Calculate server penalty per object */
- lmv_foreach_tgt(lmv, tgt) {
- if (!tgt->ltd_exp || !tgt->ltd_active)
- continue;
-
- /* bavail >> 16 to avoid overflow */
- ba = tgt_statfs_bavail(tgt) >> 16;
- if (!ba)
- continue;
-
- ba_min = min(ba, ba_min);
- ba_max = max(ba, ba_max);
-
- /* iavail >> 8 to avoid overflow */
- ia = tgt_statfs_iavail(tgt) >> 8;
- if (!ia)
- continue;
-
- ia_min = min(ia, ia_min);
- ia_max = max(ia, ia_max);
-
- /* Count the number of usable MDS's */
- if (tgt->ltd_qos.ltq_svr->lsq_bavail == 0)
- qos->lq_active_svr_count++;
- tgt->ltd_qos.ltq_svr->lsq_bavail += ba;
- tgt->ltd_qos.ltq_svr->lsq_iavail += ia;
-
- /*
- * per-MDT penalty is
- * prio * bavail * iavail / (num_tgt - 1) / 2
- */
- tgt->ltd_qos.ltq_penalty_per_obj = prio_wide * ba * ia;
- do_div(tgt->ltd_qos.ltq_penalty_per_obj, num_active - 1);
- tgt->ltd_qos.ltq_penalty_per_obj >>= 1;
-
- age = (now - tgt->ltd_qos.ltq_used) >> 3;
- if (qos->lq_reset || age > 32 * maxage)
- tgt->ltd_qos.ltq_penalty = 0;
- else if (age > maxage)
- /* Decay tgt penalty. */
- tgt->ltd_qos.ltq_penalty >>= (age / maxage);
- }
-
- num_active = qos->lq_active_svr_count;
- if (num_active < 2) {
- /*
- * If there's only 1 MDS, we can't penalize it, so instead
- * we have to double the MDT penalty
- */
- num_active = 2;
- lmv_foreach_tgt(lmv, tgt) {
- if (!tgt->ltd_exp || !tgt->ltd_active)
- continue;
-
- tgt->ltd_qos.ltq_penalty_per_obj <<= 1;
- }
- }
-
- /*
- * Per-MDS penalty is
- * prio * bavail * iavail / server_tgts / (num_svr - 1) / 2
- */
- list_for_each_entry(svr, &qos->lq_svr_list, lsq_svr_list) {
- ba = svr->lsq_bavail;
- ia = svr->lsq_iavail;
- svr->lsq_penalty_per_obj = prio_wide * ba * ia;
- do_div(ba, svr->lsq_tgt_count * (num_active - 1));
- svr->lsq_penalty_per_obj >>= 1;
-
- age = (now - svr->lsq_used) >> 3;
- if (qos->lq_reset || age > 32 * maxage)
- svr->lsq_penalty = 0;
- else if (age > maxage)
- /* Decay server penalty. */
- svr->lsq_penalty >>= age / maxage;
- }
-
- qos->lq_dirty = 0;
- qos->lq_reset = 0;
-
- /*
- * If each MDT has almost same free space, do rr allocation for better
- * creation performance
- */
- qos->lq_same_space = 0;
- if ((ba_max * (256 - qos->lq_threshold_rr)) >> 8 < ba_min &&
- (ia_max * (256 - qos->lq_threshold_rr)) >> 8 < ia_min) {
- qos->lq_same_space = 1;
- /* Reset weights for the next time we enter qos mode */
- qos->lq_reset = 1;
- }
- rc = 0;
-
-out:
- if (!rc && qos->lq_same_space)
- return -EAGAIN;
-
- return rc;
-}
-
-static inline bool lmv_qos_is_usable(struct lmv_obd *lmv)
-{
- if (!lmv->lmv_qos.lq_dirty && lmv->lmv_qos.lq_same_space)
- return false;
-
- if (lmv->desc.ld_active_tgt_count < 2)
- return false;
-
- return true;
-}
-
-/**
- * Calculate weight for a given MDT.
- *
- * The final MDT weight is bavail >> 16 * iavail >> 8 minus the MDT and MDS
- * penalties. See lmv_qos_calc_ppts() for how penalties are calculated.
- *
- * \param[in] tgt MDT target descriptor
- */
-static void lmv_qos_calc_weight(struct lu_tgt_desc *tgt)
-{
- struct lu_tgt_qos *ltq = &tgt->ltd_qos;
- u64 temp, temp2;
-
- temp = (tgt_statfs_bavail(tgt) >> 16) * (tgt_statfs_iavail(tgt) >> 8);
- temp2 = ltq->ltq_penalty + ltq->ltq_svr->lsq_penalty;
- if (temp < temp2)
- ltq->ltq_weight = 0;
- else
- ltq->ltq_weight = temp - temp2;
-}
-
-/**
- * Re-calculate weights.
- *
- * The function is called when some 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] lmv LMV device
- * \param[in] tgt target where a new object was placed
- * \param[out] total_wt new total weight for the pool
- *
- * \retval 0
- */
-static int lmv_qos_used(struct lmv_obd *lmv, struct lu_tgt_desc *tgt,
- u64 *total_wt)
-{
- struct lu_tgt_qos *ltq;
- struct lu_svr_qos *svr;
-
- ltq = &tgt->ltd_qos;
- LASSERT(ltq);
-
- /* Don't allocate on this device anymore, until the next alloc_qos */
- ltq->ltq_usable = 0;
-
- svr = ltq->ltq_svr;
-
- /*
- * Decay old penalty by half (we're adding max penalty, and don't
- * want it to run away.)
- */
- ltq->ltq_penalty >>= 1;
- svr->lsq_penalty >>= 1;
-
- /* mark the MDS and MDT as recently used */
- ltq->ltq_used = svr->lsq_used = ktime_get_real_seconds();
-
- /* Set max penalties for this MDT and MDS */
- ltq->ltq_penalty += ltq->ltq_penalty_per_obj *
- lmv->desc.ld_active_tgt_count;
- svr->lsq_penalty += svr->lsq_penalty_per_obj *
- lmv->lmv_qos.lq_active_svr_count;
-
- /* Decrease all MDS penalties */
- list_for_each_entry(svr, &lmv->lmv_qos.lq_svr_list, lsq_svr_list) {
- if (svr->lsq_penalty < svr->lsq_penalty_per_obj)
- svr->lsq_penalty = 0;
- else
- svr->lsq_penalty -= svr->lsq_penalty_per_obj;
- }
-
- *total_wt = 0;
- /* Decrease all MDT penalties */
- lmv_foreach_tgt(lmv, tgt) {
- if (!tgt->ltd_exp || !tgt->ltd_active)
- continue;
-
- if (ltq->ltq_penalty < ltq->ltq_penalty_per_obj)
- ltq->ltq_penalty = 0;
- else
- ltq->ltq_penalty -= ltq->ltq_penalty_per_obj;
-
- lmv_qos_calc_weight(tgt);
-
- /* Recalc the total weight of usable osts */
- if (ltq->ltq_usable)
- *total_wt += ltq->ltq_weight;
-
- CDEBUG(D_OTHER,
- "recalc tgt %d usable=%d avail=%llu tgtppo=%llu tgtp=%llu svrppo=%llu svrp=%llu wt=%llu\n",
- tgt->ltd_index, ltq->ltq_usable,
- tgt_statfs_bavail(tgt) >> 10,
- ltq->ltq_penalty_per_obj >> 10,
- ltq->ltq_penalty >> 10,
- ltq->ltq_svr->lsq_penalty_per_obj >> 10,
- ltq->ltq_svr->lsq_penalty >> 10,
- ltq->ltq_weight >> 10);
- }
-
- return 0;
-}
-
-struct lu_tgt_desc *lmv_locate_tgt_qos(struct lmv_obd *lmv, u32 *mdt)
-{
- struct lu_tgt_desc *tgt;
- u64 total_weight = 0;
- u64 cur_weight = 0;
- u64 rand;
- int rc;
-
- if (!lmv_qos_is_usable(lmv))
- return ERR_PTR(-EAGAIN);
-
- down_write(&lmv->lmv_qos.lq_rw_sem);
-
- if (!lmv_qos_is_usable(lmv)) {
- tgt = ERR_PTR(-EAGAIN);
- goto unlock;
- }
-
- rc = lmv_qos_calc_ppts(lmv);
- if (rc) {
- tgt = ERR_PTR(rc);
- goto unlock;
- }
-
- lmv_foreach_tgt(lmv, tgt) {
- tgt->ltd_qos.ltq_usable = 0;
- if (!tgt->ltd_exp || !tgt->ltd_active)
- continue;
-
- tgt->ltd_qos.ltq_usable = 1;
- lmv_qos_calc_weight(tgt);
- total_weight += tgt->ltd_qos.ltq_weight;
- }
-
- rand = lu_prandom_u64_max(total_weight);
-
- lmv_foreach_tgt(lmv, tgt) {
- if (!tgt->ltd_qos.ltq_usable)
- continue;
-
- cur_weight += tgt->ltd_qos.ltq_weight;
- if (cur_weight < rand)
- continue;
-
- *mdt = tgt->ltd_index;
- lmv_qos_used(lmv, tgt, &total_weight);
- rc = 0;
- goto unlock;
- }
-
- /* no proper target found */
- tgt = ERR_PTR(-EAGAIN);
- goto unlock;
-unlock:
- up_write(&lmv->lmv_qos.lq_rw_sem);
-
- return tgt;
-}
-
-struct lu_tgt_desc *lmv_locate_tgt_rr(struct lmv_obd *lmv, u32 *mdt)
-{
- struct lu_tgt_desc *tgt;
- int i;
-
- spin_lock(&lmv->lmv_qos.lq_rr.lqr_alloc);
- for (i = 0; i < lmv->desc.ld_tgt_count; i++) {
- tgt = lmv_tgt(lmv,
- (i + lmv->lmv_qos_rr_index) % lmv->desc.ld_tgt_count);
- if (!tgt || !tgt->ltd_exp || !tgt->ltd_active)
- continue;
-
- *mdt = tgt->ltd_index;
- lmv->lmv_qos_rr_index =
- (i + lmv->lmv_qos_rr_index + 1) %
- lmv->desc.ld_tgt_count;
- spin_unlock(&lmv->lmv_qos.lq_rr.lqr_alloc);
-
- return tgt;
- }
- spin_unlock(&lmv->lmv_qos.lq_rr.lqr_alloc);
-
- return ERR_PTR(-ENODEV);
-}
diff --git a/fs/lustre/obdclass/lu_qos.c b/fs/lustre/obdclass/lu_qos.c
index d4803e8..e77e81d 100644
--- a/fs/lustre/obdclass/lu_qos.c
+++ b/fs/lustre/obdclass/lu_qos.c
@@ -207,3 +207,306 @@ u64 lu_prandom_u64_max(u64 ep_ro)
return rand;
}
EXPORT_SYMBOL(lu_prandom_u64_max);
+
+static inline u64 tgt_statfs_bavail(struct lu_tgt_desc *tgt)
+{
+ struct obd_statfs *statfs = &tgt->ltd_statfs;
+
+ return statfs->os_bavail * statfs->os_bsize;
+}
+
+static inline u64 tgt_statfs_iavail(struct lu_tgt_desc *tgt)
+{
+ return tgt->ltd_statfs.os_ffree;
+}
+
+/**
+ * Calculate penalties per-tgt and per-server
+ *
+ * Re-calculate penalties when the configuration changes, active targets
+ * change and after statfs refresh (all these are reflected by lq_dirty flag).
+ * On every tgt and server: 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 server/tgt under light load.
+ * See lqos_calc_weight() for how penalties are factored into the weight.
+ *
+ * @qos lu_qos
+ * @ltd lu_tgt_descs
+ * @active_tgt_nr active tgt number
+ * @ maxage qos max age
+ * @is_mdt MDT will count inode usage
+ *
+ * Return: 0 on success
+ * -EAGAIN the number of tgt isn't enough or all
+ * tgt spaces are almost the same
+ */
+int lqos_calc_penalties(struct lu_qos *qos, struct lu_tgt_descs *ltd,
+ u32 active_tgt_nr, u32 maxage, bool is_mdt)
+{
+ struct lu_tgt_desc *tgt;
+ struct lu_svr_qos *svr;
+ u64 ba_max, ba_min, ba;
+ u64 ia_max, ia_min, ia = 1;
+ u32 num_active;
+ int prio_wide;
+ time64_t now, age;
+ int rc;
+
+ if (!qos->lq_dirty) {
+ rc = 0;
+ goto out;
+ }
+
+ num_active = active_tgt_nr - 1;
+ if (num_active < 1) {
+ rc = -EAGAIN;
+ goto out;
+ }
+
+ /* find bavail on each server */
+ list_for_each_entry(svr, &qos->lq_svr_list, lsq_svr_list) {
+ svr->lsq_bavail = 0;
+ /* if inode is not counted, set to 1 to ignore */
+ svr->lsq_iavail = is_mdt ? 0 : 1;
+ }
+ qos->lq_active_svr_count = 0;
+
+ /*
+ * How badly user wants to select targets "widely" (not recently chosen
+ * and not on recent MDS's). As opposed to "freely" (free space avail.)
+ * 0-256
+ */
+ prio_wide = 256 - qos->lq_prio_free;
+
+ ba_min = (u64)(-1);
+ ba_max = 0;
+ ia_min = (u64)(-1);
+ ia_max = 0;
+ now = ktime_get_real_seconds();
+
+ /* Calculate server penalty per object */
+ ltd_foreach_tgt(ltd, tgt) {
+ if (!tgt->ltd_active)
+ continue;
+
+ /* when inode is counted, bavail >> 16 to avoid overflow */
+ ba = tgt_statfs_bavail(tgt);
+ if (is_mdt)
+ ba >>= 16;
+ else
+ ba >>= 8;
+ if (!ba)
+ continue;
+
+ ba_min = min(ba, ba_min);
+ ba_max = max(ba, ba_max);
+
+ /* Count the number of usable servers */
+ if (tgt->ltd_qos.ltq_svr->lsq_bavail == 0)
+ qos->lq_active_svr_count++;
+ tgt->ltd_qos.ltq_svr->lsq_bavail += ba;
+
+ if (is_mdt) {
+ /* iavail >> 8 to avoid overflow */
+ ia = tgt_statfs_iavail(tgt) >> 8;
+ if (!ia)
+ continue;
+
+ ia_min = min(ia, ia_min);
+ ia_max = max(ia, ia_max);
+
+ tgt->ltd_qos.ltq_svr->lsq_iavail += ia;
+ }
+
+ /*
+ * per-tgt penalty is
+ * prio * bavail * iavail / (num_tgt - 1) / 2
+ */
+ tgt->ltd_qos.ltq_penalty_per_obj = prio_wide * ba * ia;
+ do_div(tgt->ltd_qos.ltq_penalty_per_obj, num_active);
+ tgt->ltd_qos.ltq_penalty_per_obj >>= 1;
+
+ age = (now - tgt->ltd_qos.ltq_used) >> 3;
+ if (qos->lq_reset || age > 32 * maxage)
+ tgt->ltd_qos.ltq_penalty = 0;
+ else if (age > maxage)
+ /* Decay tgt penalty. */
+ tgt->ltd_qos.ltq_penalty >>= (age / maxage);
+ }
+
+ num_active = qos->lq_active_svr_count - 1;
+ if (num_active < 1) {
+ /*
+ * If there's only 1 server, we can't penalize it, so instead
+ * we have to double the tgt penalty
+ */
+ num_active = 1;
+ ltd_foreach_tgt(ltd, tgt) {
+ if (!tgt->ltd_active)
+ continue;
+
+ tgt->ltd_qos.ltq_penalty_per_obj <<= 1;
+ }
+ }
+
+ /*
+ * Per-server penalty is
+ * prio * bavail * iavail / server_tgts / (num_svr - 1) / 2
+ */
+ list_for_each_entry(svr, &qos->lq_svr_list, lsq_svr_list) {
+ ba = svr->lsq_bavail;
+ ia = svr->lsq_iavail;
+ svr->lsq_penalty_per_obj = prio_wide * ba * ia;
+ do_div(ba, svr->lsq_tgt_count * num_active);
+ svr->lsq_penalty_per_obj >>= 1;
+
+ age = (now - svr->lsq_used) >> 3;
+ if (qos->lq_reset || age > 32 * maxage)
+ svr->lsq_penalty = 0;
+ else if (age > maxage)
+ /* Decay server penalty. */
+ svr->lsq_penalty >>= age / maxage;
+ }
+
+ qos->lq_dirty = 0;
+ qos->lq_reset = 0;
+
+ /*
+ * If each tgt has almost same free space, do rr allocation for better
+ * creation performance
+ */
+ qos->lq_same_space = 0;
+ if ((ba_max * (256 - qos->lq_threshold_rr)) >> 8 < ba_min &&
+ (ia_max * (256 - qos->lq_threshold_rr)) >> 8 < ia_min) {
+ qos->lq_same_space = 1;
+ /* Reset weights for the next time we enter qos mode */
+ qos->lq_reset = 1;
+ }
+ rc = 0;
+
+out:
+ if (!rc && qos->lq_same_space)
+ return -EAGAIN;
+
+ return rc;
+}
+EXPORT_SYMBOL(lqos_calc_penalties);
+
+bool lqos_is_usable(struct lu_qos *qos, u32 active_tgt_nr)
+{
+ if (!qos->lq_dirty && qos->lq_same_space)
+ return false;
+
+ if (active_tgt_nr < 2)
+ return false;
+
+ return true;
+}
+EXPORT_SYMBOL(lqos_is_usable);
+
+/**
+ * Calculate weight for a given tgt.
+ *
+ * The final tgt weight is bavail >> 16 * iavail >> 8 minus the tgt and server
+ * penalties. See lqos_calc_ppts() for how penalties are calculated.
+ *
+ * @tgt target descriptor
+ */
+void lqos_calc_weight(struct lu_tgt_desc *tgt)
+{
+ struct lu_tgt_qos *ltq = &tgt->ltd_qos;
+ u64 temp, temp2;
+
+ temp = (tgt_statfs_bavail(tgt) >> 16) * (tgt_statfs_iavail(tgt) >> 8);
+ temp2 = ltq->ltq_penalty + ltq->ltq_svr->lsq_penalty;
+ if (temp < temp2)
+ ltq->ltq_weight = 0;
+ else
+ ltq->ltq_weight = temp - temp2;
+}
+EXPORT_SYMBOL(lqos_calc_weight);
+
+/**
+ * Re-calculate weights.
+ *
+ * The function is called when some target was used for a new object. In
+ * this case we should re-calculate all the weights to keep new allocations
+ * balanced well.
+ *
+ * @qos lu_qos
+ * @ltd lu_tgt_descs
+ * @tgt target where a new object was placed
+ * @active_tgt_nr active tgt number
+ * @total_wt new total weight for the pool
+ *
+ * Return: 0
+ */
+int lqos_recalc_weight(struct lu_qos *qos, struct lu_tgt_descs *ltd,
+ struct lu_tgt_desc *tgt, u32 active_tgt_nr,
+ u64 *total_wt)
+{
+ struct lu_tgt_qos *ltq;
+ struct lu_svr_qos *svr;
+
+ ltq = &tgt->ltd_qos;
+ LASSERT(ltq);
+
+ /* Don't allocate on this device anymore, until the next alloc_qos */
+ ltq->ltq_usable = 0;
+
+ svr = ltq->ltq_svr;
+
+ /*
+ * Decay old penalty by half (we're adding max penalty, and don't
+ * want it to run away.)
+ */
+ ltq->ltq_penalty >>= 1;
+ svr->lsq_penalty >>= 1;
+
+ /* mark the server and tgt as recently used */
+ ltq->ltq_used = svr->lsq_used = ktime_get_real_seconds();
+
+ /* Set max penalties for this tgt and server */
+ ltq->ltq_penalty += ltq->ltq_penalty_per_obj * active_tgt_nr;
+ svr->lsq_penalty += svr->lsq_penalty_per_obj * active_tgt_nr;
+
+ /* Decrease all MDS penalties */
+ list_for_each_entry(svr, &qos->lq_svr_list, lsq_svr_list) {
+ if (svr->lsq_penalty < svr->lsq_penalty_per_obj)
+ svr->lsq_penalty = 0;
+ else
+ svr->lsq_penalty -= svr->lsq_penalty_per_obj;
+ }
+
+ *total_wt = 0;
+ /* Decrease all tgt penalties */
+ ltd_foreach_tgt(ltd, tgt) {
+ if (!tgt->ltd_active)
+ continue;
+
+ if (ltq->ltq_penalty < ltq->ltq_penalty_per_obj)
+ ltq->ltq_penalty = 0;
+ else
+ ltq->ltq_penalty -= ltq->ltq_penalty_per_obj;
+
+ lqos_calc_weight(tgt);
+
+ /* Recalc the total weight of usable osts */
+ if (ltq->ltq_usable)
+ *total_wt += ltq->ltq_weight;
+
+ CDEBUG(D_OTHER,
+ "recalc tgt %d usable=%d avail=%llu tgtppo=%llu tgtp=%llu svrppo=%llu svrp=%llu wt=%llu\n",
+ tgt->ltd_index, ltq->ltq_usable,
+ tgt_statfs_bavail(tgt) >> 10,
+ ltq->ltq_penalty_per_obj >> 10,
+ ltq->ltq_penalty >> 10,
+ ltq->ltq_svr->lsq_penalty_per_obj >> 10,
+ ltq->ltq_svr->lsq_penalty >> 10,
+ ltq->ltq_weight >> 10);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(lqos_recalc_weight);
--
1.8.3.1
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