summaryrefslogtreecommitdiffstats
path: root/block
diff options
context:
space:
mode:
Diffstat (limited to 'block')
-rw-r--r--block/bfq-cgroup.c116
-rw-r--r--block/bfq-iosched.c2
-rw-r--r--block/bfq-iosched.h23
-rw-r--r--block/bio-integrity.c3
-rw-r--r--block/blk-cgroup.c2
-rw-r--r--block/blk-core.c10
-rw-r--r--block/blk-mq.c54
-rw-r--r--block/blk-sysfs.c42
-rw-r--r--block/blk-throttle.c184
-rw-r--r--block/blk.h2
-rw-r--r--block/cfq-iosched.c17
-rw-r--r--block/partition-generic.c4
-rw-r--r--block/partitions/msdos.c2
13 files changed, 312 insertions, 149 deletions
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index c8a32fb345cf5..78b2e0db4fb2c 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -52,7 +52,7 @@ BFQG_FLAG_FNS(idling)
BFQG_FLAG_FNS(empty)
#undef BFQG_FLAG_FNS
-/* This should be called with the queue_lock held. */
+/* This should be called with the scheduler lock held. */
static void bfqg_stats_update_group_wait_time(struct bfqg_stats *stats)
{
unsigned long long now;
@@ -67,7 +67,7 @@ static void bfqg_stats_update_group_wait_time(struct bfqg_stats *stats)
bfqg_stats_clear_waiting(stats);
}
-/* This should be called with the queue_lock held. */
+/* This should be called with the scheduler lock held. */
static void bfqg_stats_set_start_group_wait_time(struct bfq_group *bfqg,
struct bfq_group *curr_bfqg)
{
@@ -81,7 +81,7 @@ static void bfqg_stats_set_start_group_wait_time(struct bfq_group *bfqg,
bfqg_stats_mark_waiting(stats);
}
-/* This should be called with the queue_lock held. */
+/* This should be called with the scheduler lock held. */
static void bfqg_stats_end_empty_time(struct bfqg_stats *stats)
{
unsigned long long now;
@@ -203,12 +203,30 @@ struct bfq_group *bfqq_group(struct bfq_queue *bfqq)
static void bfqg_get(struct bfq_group *bfqg)
{
- return blkg_get(bfqg_to_blkg(bfqg));
+ bfqg->ref++;
}
void bfqg_put(struct bfq_group *bfqg)
{
- return blkg_put(bfqg_to_blkg(bfqg));
+ bfqg->ref--;
+
+ if (bfqg->ref == 0)
+ kfree(bfqg);
+}
+
+static void bfqg_and_blkg_get(struct bfq_group *bfqg)
+{
+ /* see comments in bfq_bic_update_cgroup for why refcounting bfqg */
+ bfqg_get(bfqg);
+
+ blkg_get(bfqg_to_blkg(bfqg));
+}
+
+void bfqg_and_blkg_put(struct bfq_group *bfqg)
+{
+ bfqg_put(bfqg);
+
+ blkg_put(bfqg_to_blkg(bfqg));
}
void bfqg_stats_update_io_add(struct bfq_group *bfqg, struct bfq_queue *bfqq,
@@ -312,7 +330,11 @@ void bfq_init_entity(struct bfq_entity *entity, struct bfq_group *bfqg)
if (bfqq) {
bfqq->ioprio = bfqq->new_ioprio;
bfqq->ioprio_class = bfqq->new_ioprio_class;
- bfqg_get(bfqg);
+ /*
+ * Make sure that bfqg and its associated blkg do not
+ * disappear before entity.
+ */
+ bfqg_and_blkg_get(bfqg);
}
entity->parent = bfqg->my_entity; /* NULL for root group */
entity->sched_data = &bfqg->sched_data;
@@ -399,6 +421,8 @@ struct blkg_policy_data *bfq_pd_alloc(gfp_t gfp, int node)
return NULL;
}
+ /* see comments in bfq_bic_update_cgroup for why refcounting */
+ bfqg_get(bfqg);
return &bfqg->pd;
}
@@ -426,7 +450,7 @@ void bfq_pd_free(struct blkg_policy_data *pd)
struct bfq_group *bfqg = pd_to_bfqg(pd);
bfqg_stats_exit(&bfqg->stats);
- return kfree(bfqg);
+ bfqg_put(bfqg);
}
void bfq_pd_reset_stats(struct blkg_policy_data *pd)
@@ -496,9 +520,10 @@ struct bfq_group *bfq_find_set_group(struct bfq_data *bfqd,
* Move @bfqq to @bfqg, deactivating it from its old group and reactivating
* it on the new one. Avoid putting the entity on the old group idle tree.
*
- * Must be called under the queue lock; the cgroup owning @bfqg must
- * not disappear (by now this just means that we are called under
- * rcu_read_lock()).
+ * Must be called under the scheduler lock, to make sure that the blkg
+ * owning @bfqg does not disappear (see comments in
+ * bfq_bic_update_cgroup on guaranteeing the consistency of blkg
+ * objects).
*/
void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
struct bfq_group *bfqg)
@@ -519,16 +544,12 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bfq_deactivate_bfqq(bfqd, bfqq, false, false);
else if (entity->on_st)
bfq_put_idle_entity(bfq_entity_service_tree(entity), entity);
- bfqg_put(bfqq_group(bfqq));
+ bfqg_and_blkg_put(bfqq_group(bfqq));
- /*
- * Here we use a reference to bfqg. We don't need a refcounter
- * as the cgroup reference will not be dropped, so that its
- * destroy() callback will not be invoked.
- */
entity->parent = bfqg->my_entity;
entity->sched_data = &bfqg->sched_data;
- bfqg_get(bfqg);
+ /* pin down bfqg and its associated blkg */
+ bfqg_and_blkg_get(bfqg);
if (bfq_bfqq_busy(bfqq)) {
bfq_pos_tree_add_move(bfqd, bfqq);
@@ -545,8 +566,9 @@ void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq,
* @bic: the bic to move.
* @blkcg: the blk-cgroup to move to.
*
- * Move bic to blkcg, assuming that bfqd->queue is locked; the caller
- * has to make sure that the reference to cgroup is valid across the call.
+ * Move bic to blkcg, assuming that bfqd->lock is held; which makes
+ * sure that the reference to cgroup is valid across the call (see
+ * comments in bfq_bic_update_cgroup on this issue)
*
* NOTE: an alternative approach might have been to store the current
* cgroup in bfqq and getting a reference to it, reducing the lookup
@@ -604,6 +626,57 @@ void bfq_bic_update_cgroup(struct bfq_io_cq *bic, struct bio *bio)
goto out;
bfqg = __bfq_bic_change_cgroup(bfqd, bic, bio_blkcg(bio));
+ /*
+ * Update blkg_path for bfq_log_* functions. We cache this
+ * path, and update it here, for the following
+ * reasons. Operations on blkg objects in blk-cgroup are
+ * protected with the request_queue lock, and not with the
+ * lock that protects the instances of this scheduler
+ * (bfqd->lock). This exposes BFQ to the following sort of
+ * race.
+ *
+ * The blkg_lookup performed in bfq_get_queue, protected
+ * through rcu, may happen to return the address of a copy of
+ * the original blkg. If this is the case, then the
+ * bfqg_and_blkg_get performed in bfq_get_queue, to pin down
+ * the blkg, is useless: it does not prevent blk-cgroup code
+ * from destroying both the original blkg and all objects
+ * directly or indirectly referred by the copy of the
+ * blkg.
+ *
+ * On the bright side, destroy operations on a blkg invoke, as
+ * a first step, hooks of the scheduler associated with the
+ * blkg. And these hooks are executed with bfqd->lock held for
+ * BFQ. As a consequence, for any blkg associated with the
+ * request queue this instance of the scheduler is attached
+ * to, we are guaranteed that such a blkg is not destroyed, and
+ * that all the pointers it contains are consistent, while we
+ * are holding bfqd->lock. A blkg_lookup performed with
+ * bfqd->lock held then returns a fully consistent blkg, which
+ * remains consistent until this lock is held.
+ *
+ * Thanks to the last fact, and to the fact that: (1) bfqg has
+ * been obtained through a blkg_lookup in the above
+ * assignment, and (2) bfqd->lock is being held, here we can
+ * safely use the policy data for the involved blkg (i.e., the
+ * field bfqg->pd) to get to the blkg associated with bfqg,
+ * and then we can safely use any field of blkg. After we
+ * release bfqd->lock, even just getting blkg through this
+ * bfqg may cause dangling references to be traversed, as
+ * bfqg->pd may not exist any more.
+ *
+ * In view of the above facts, here we cache, in the bfqg, any
+ * blkg data we may need for this bic, and for its associated
+ * bfq_queue. As of now, we need to cache only the path of the
+ * blkg, which is used in the bfq_log_* functions.
+ *
+ * Finally, note that bfqg itself needs to be protected from
+ * destruction on the blkg_free of the original blkg (which
+ * invokes bfq_pd_free). We use an additional private
+ * refcounter for bfqg, to let it disappear only after no
+ * bfq_queue refers to it any longer.
+ */
+ blkg_path(bfqg_to_blkg(bfqg), bfqg->blkg_path, sizeof(bfqg->blkg_path));
bic->blkcg_serial_nr = serial_nr;
out:
rcu_read_unlock();
@@ -640,8 +713,6 @@ static void bfq_reparent_leaf_entity(struct bfq_data *bfqd,
* @bfqd: the device data structure with the root group.
* @bfqg: the group to move from.
* @st: the service tree with the entities.
- *
- * Needs queue_lock to be taken and reference to be valid over the call.
*/
static void bfq_reparent_active_entities(struct bfq_data *bfqd,
struct bfq_group *bfqg,
@@ -692,8 +763,7 @@ void bfq_pd_offline(struct blkg_policy_data *pd)
/*
* The idle tree may still contain bfq_queues belonging
* to exited task because they never migrated to a different
- * cgroup from the one being destroyed now. No one else
- * can access them so it's safe to act without any lock.
+ * cgroup from the one being destroyed now.
*/
bfq_flush_idle_tree(st);
diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 08ce450963505..ed93da2462abb 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -3665,7 +3665,7 @@ void bfq_put_queue(struct bfq_queue *bfqq)
kmem_cache_free(bfq_pool, bfqq);
#ifdef CONFIG_BFQ_GROUP_IOSCHED
- bfqg_put(bfqg);
+ bfqg_and_blkg_put(bfqg);
#endif
}
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index ae783c06dfd9c..5c3bf98614921 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -759,6 +759,12 @@ struct bfq_group {
/* must be the first member */
struct blkg_policy_data pd;
+ /* cached path for this blkg (see comments in bfq_bic_update_cgroup) */
+ char blkg_path[128];
+
+ /* reference counter (see comments in bfq_bic_update_cgroup) */
+ int ref;
+
struct bfq_entity entity;
struct bfq_sched_data sched_data;
@@ -838,7 +844,7 @@ struct bfq_group *bfq_find_set_group(struct bfq_data *bfqd,
struct blkcg_gq *bfqg_to_blkg(struct bfq_group *bfqg);
struct bfq_group *bfqq_group(struct bfq_queue *bfqq);
struct bfq_group *bfq_create_group_hierarchy(struct bfq_data *bfqd, int node);
-void bfqg_put(struct bfq_group *bfqg);
+void bfqg_and_blkg_put(struct bfq_group *bfqg);
#ifdef CONFIG_BFQ_GROUP_IOSCHED
extern struct cftype bfq_blkcg_legacy_files[];
@@ -910,20 +916,13 @@ void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq);
struct bfq_group *bfqq_group(struct bfq_queue *bfqq);
#define bfq_log_bfqq(bfqd, bfqq, fmt, args...) do { \
- char __pbuf[128]; \
- \
- blkg_path(bfqg_to_blkg(bfqq_group(bfqq)), __pbuf, sizeof(__pbuf)); \
- blk_add_trace_msg((bfqd)->queue, "bfq%d%c %s " fmt, (bfqq)->pid, \
+ blk_add_trace_msg((bfqd)->queue, "bfq%d%c %s " fmt, (bfqq)->pid,\
bfq_bfqq_sync((bfqq)) ? 'S' : 'A', \
- __pbuf, ##args); \
+ bfqq_group(bfqq)->blkg_path, ##args); \
} while (0)
-#define bfq_log_bfqg(bfqd, bfqg, fmt, args...) do { \
- char __pbuf[128]; \
- \
- blkg_path(bfqg_to_blkg(bfqg), __pbuf, sizeof(__pbuf)); \
- blk_add_trace_msg((bfqd)->queue, "%s " fmt, __pbuf, ##args); \
-} while (0)
+#define bfq_log_bfqg(bfqd, bfqg, fmt, args...) \
+ blk_add_trace_msg((bfqd)->queue, "%s " fmt, (bfqg)->blkg_path, ##args)
#else /* CONFIG_BFQ_GROUP_IOSCHED */
diff --git a/block/bio-integrity.c b/block/bio-integrity.c
index 5384713d48bc9..b5009a896a7fa 100644
--- a/block/bio-integrity.c
+++ b/block/bio-integrity.c
@@ -175,6 +175,9 @@ bool bio_integrity_enabled(struct bio *bio)
if (bio_op(bio) != REQ_OP_READ && bio_op(bio) != REQ_OP_WRITE)
return false;
+ if (!bio_sectors(bio))
+ return false;
+
/* Already protected? */
if (bio_integrity(bio))
return false;
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 7c2947128f581..0480892e97e50 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -74,7 +74,7 @@ static void blkg_free(struct blkcg_gq *blkg)
blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
if (blkg->blkcg != &blkcg_root)
- blk_exit_rl(&blkg->rl);
+ blk_exit_rl(blkg->q, &blkg->rl);
blkg_rwstat_exit(&blkg->stat_ios);
blkg_rwstat_exit(&blkg->stat_bytes);
diff --git a/block/blk-core.c b/block/blk-core.c
index c7068520794bd..a7421b772d0e0 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -648,13 +648,19 @@ int blk_init_rl(struct request_list *rl, struct request_queue *q,
if (!rl->rq_pool)
return -ENOMEM;
+ if (rl != &q->root_rl)
+ WARN_ON_ONCE(!blk_get_queue(q));
+
return 0;
}
-void blk_exit_rl(struct request_list *rl)
+void blk_exit_rl(struct request_queue *q, struct request_list *rl)
{
- if (rl->rq_pool)
+ if (rl->rq_pool) {
mempool_destroy(rl->rq_pool);
+ if (rl != &q->root_rl)
+ blk_put_queue(q);
+ }
}
struct request_queue *blk_alloc_queue(gfp_t gfp_mask)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index a69ad122ed66c..bb66c96850b18 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -628,25 +628,6 @@ void blk_mq_delay_kick_requeue_list(struct request_queue *q,
}
EXPORT_SYMBOL(blk_mq_delay_kick_requeue_list);
-void blk_mq_abort_requeue_list(struct request_queue *q)
-{
- unsigned long flags;
- LIST_HEAD(rq_list);
-
- spin_lock_irqsave(&q->requeue_lock, flags);
- list_splice_init(&q->requeue_list, &rq_list);
- spin_unlock_irqrestore(&q->requeue_lock, flags);
-
- while (!list_empty(&rq_list)) {
- struct request *rq;
-
- rq = list_first_entry(&rq_list, struct request, queuelist);
- list_del_init(&rq->queuelist);
- blk_mq_end_request(rq, -EIO);
- }
-}
-EXPORT_SYMBOL(blk_mq_abort_requeue_list);
-
struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag)
{
if (tag < tags->nr_tags) {
@@ -1480,22 +1461,28 @@ static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq)
return blk_tag_to_qc_t(rq->internal_tag, hctx->queue_num, true);
}
-static void __blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie,
- bool may_sleep)
+static void __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
+ struct request *rq,
+ blk_qc_t *cookie, bool may_sleep)
{
struct request_queue *q = rq->q;
struct blk_mq_queue_data bd = {
.rq = rq,
.last = true,
};
- struct blk_mq_hw_ctx *hctx;
blk_qc_t new_cookie;
int ret;
+ bool run_queue = true;
+
+ if (blk_mq_hctx_stopped(hctx)) {
+ run_queue = false;
+ goto insert;
+ }
if (q->elevator)
goto insert;
- if (!blk_mq_get_driver_tag(rq, &hctx, false))
+ if (!blk_mq_get_driver_tag(rq, NULL, false))
goto insert;
new_cookie = request_to_qc_t(hctx, rq);
@@ -1519,7 +1506,7 @@ static void __blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie,
__blk_mq_requeue_request(rq);
insert:
- blk_mq_sched_insert_request(rq, false, true, false, may_sleep);
+ blk_mq_sched_insert_request(rq, false, run_queue, false, may_sleep);
}
static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
@@ -1527,7 +1514,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
{
if (!(hctx->flags & BLK_MQ_F_BLOCKING)) {
rcu_read_lock();
- __blk_mq_try_issue_directly(rq, cookie, false);
+ __blk_mq_try_issue_directly(hctx, rq, cookie, false);
rcu_read_unlock();
} else {
unsigned int srcu_idx;
@@ -1535,7 +1522,7 @@ static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
might_sleep();
srcu_idx = srcu_read_lock(&hctx->queue_rq_srcu);
- __blk_mq_try_issue_directly(rq, cookie, true);
+ __blk_mq_try_issue_directly(hctx, rq, cookie, true);
srcu_read_unlock(&hctx->queue_rq_srcu, srcu_idx);
}
}
@@ -1638,9 +1625,12 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
blk_mq_put_ctx(data.ctx);
- if (same_queue_rq)
+ if (same_queue_rq) {
+ data.hctx = blk_mq_map_queue(q,
+ same_queue_rq->mq_ctx->cpu);
blk_mq_try_issue_directly(data.hctx, same_queue_rq,
&cookie);
+ }
} else if (q->nr_hw_queues > 1 && is_sync) {
blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio);
@@ -2660,7 +2650,8 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
return ret;
}
-void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues)
+static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set,
+ int nr_hw_queues)
{
struct request_queue *q;
@@ -2684,6 +2675,13 @@ void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues)
list_for_each_entry(q, &set->tag_list, tag_set_list)
blk_mq_unfreeze_queue(q);
}
+
+void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues)
+{
+ mutex_lock(&set->tag_list_lock);
+ __blk_mq_update_nr_hw_queues(set, nr_hw_queues);
+ mutex_unlock(&set->tag_list_lock);
+}
EXPORT_SYMBOL_GPL(blk_mq_update_nr_hw_queues);
/* Enable polling stats and return whether they were already enabled. */
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 504fee9400523..27aceab1cc314 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -777,24 +777,25 @@ static void blk_free_queue_rcu(struct rcu_head *rcu_head)
}
/**
- * blk_release_queue: - release a &struct request_queue when it is no longer needed
- * @kobj: the kobj belonging to the request queue to be released
+ * __blk_release_queue - release a request queue when it is no longer needed
+ * @work: pointer to the release_work member of the request queue to be released
*
* Description:
- * blk_release_queue is the pair to blk_init_queue() or
- * blk_queue_make_request(). It should be called when a request queue is
- * being released; typically when a block device is being de-registered.
- * Currently, its primary task it to free all the &struct request
- * structures that were allocated to the queue and the queue itself.
+ * blk_release_queue is the counterpart of blk_init_queue(). It should be
+ * called when a request queue is being released; typically when a block
+ * device is being de-registered. Its primary task it to free the queue
+ * itself.
*
- * Note:
+ * Notes:
* The low level driver must have finished any outstanding requests first
* via blk_cleanup_queue().
- **/
-static void blk_release_queue(struct kobject *kobj)
+ *
+ * Although blk_release_queue() may be called with preemption disabled,
+ * __blk_release_queue() may sleep.
+ */
+static void __blk_release_queue(struct work_struct *work)
{
- struct request_queue *q =
- container_of(kobj, struct request_queue, kobj);
+ struct request_queue *q = container_of(work, typeof(*q), release_work);
if (test_bit(QUEUE_FLAG_POLL_STATS, &q->queue_flags))
blk_stat_remove_callback(q, q->poll_cb);
@@ -809,7 +810,7 @@ static void blk_release_queue(struct kobject *kobj)
blk_free_queue_stats(q->stats);
- blk_exit_rl(&q->root_rl);
+ blk_exit_rl(q, &q->root_rl);
if (q->queue_tags)
__blk_queue_free_tags(q);
@@ -834,6 +835,15 @@ static void blk_release_queue(struct kobject *kobj)
call_rcu(&q->rcu_head, blk_free_queue_rcu);
}
+static void blk_release_queue(struct kobject *kobj)
+{
+ struct request_queue *q =
+ container_of(kobj, struct request_queue, kobj);
+
+ INIT_WORK(&q->release_work, __blk_release_queue);
+ schedule_work(&q->release_work);
+}
+
static const struct sysfs_ops queue_sysfs_ops = {
.show = queue_attr_show,
.store = queue_attr_store,
@@ -887,10 +897,10 @@ int blk_register_queue(struct gendisk *disk)
goto unlock;
}
- if (q->mq_ops)
+ if (q->mq_ops) {
__blk_mq_register_dev(dev, q);
-
- blk_mq_debugfs_register(q);
+ blk_mq_debugfs_register(q);
+ }
kobject_uevent(&q->kobj, KOBJ_ADD);
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index b78db2e5fdff1..a7285bf2831c7 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -22,11 +22,18 @@ static int throtl_quantum = 32;
#define DFL_THROTL_SLICE_HD (HZ / 10)
#define DFL_THROTL_SLICE_SSD (HZ / 50)
#define MAX_THROTL_SLICE (HZ)
-#define DFL_IDLE_THRESHOLD_SSD (1000L) /* 1 ms */
-#define DFL_IDLE_THRESHOLD_HD (100L * 1000) /* 100 ms */
#define MAX_IDLE_TIME (5L * 1000 * 1000) /* 5 s */
-/* default latency target is 0, eg, guarantee IO latency by default */
-#define DFL_LATENCY_TARGET (0)
+#define MIN_THROTL_BPS (320 * 1024)
+#define MIN_THROTL_IOPS (10)
+#define DFL_LATENCY_TARGET (-1L)
+#define DFL_IDLE_THRESHOLD (0)
+#define DFL_HD_BASELINE_LATENCY (4000L) /* 4ms */
+#define LATENCY_FILTERED_SSD (0)
+/*
+ * For HD, very small latency comes from sequential IO. Such IO is helpless to
+ * help determine if its IO is impacted by others, hence we ignore the IO
+ */
+#define LATENCY_FILTERED_HD (1000L) /* 1ms */
#define SKIP_LATENCY (((u64)1) << BLK_STAT_RES_SHIFT)
@@ -157,6 +164,7 @@ struct throtl_grp {
unsigned long last_check_time;
unsigned long latency_target; /* us */
+ unsigned long latency_target_conf; /* us */
/* When did we start a new slice */
unsigned long slice_start[2];
unsigned long slice_end[2];
@@ -165,6 +173,7 @@ struct throtl_grp {
unsigned long checked_last_finish_time; /* ns / 1024 */
unsigned long avg_idletime; /* ns / 1024 */
unsigned long idletime_threshold; /* us */
+ unsigned long idletime_threshold_conf; /* us */
unsigned int bio_cnt; /* total bios */
unsigned int bad_bio_cnt; /* bios exceeding latency threshold */
@@ -201,8 +210,6 @@ struct throtl_data
unsigned int limit_index;
bool limit_valid[LIMIT_CNT];
- unsigned long dft_idletime_threshold; /* us */
-
unsigned long low_upgrade_time;
unsigned long low_downgrade_time;
@@ -212,6 +219,7 @@ struct throtl_data
struct avg_latency_bucket avg_buckets[LATENCY_BUCKET_SIZE];
struct latency_bucket __percpu *latency_buckets;
unsigned long last_calculate_time;
+ unsigned long filtered_latency;
bool track_bio_latency;
};
@@ -294,8 +302,14 @@ static uint64_t tg_bps_limit(struct throtl_grp *tg, int rw)
td = tg->td;
ret = tg->bps[rw][td->limit_index];
- if (ret == 0 && td->limit_index == LIMIT_LOW)
- return tg->bps[rw][LIMIT_MAX];
+ if (ret == 0 && td->limit_index == LIMIT_LOW) {
+ /* intermediate node or iops isn't 0 */
+ if (!list_empty(&blkg->blkcg->css.children) ||
+ tg->iops[rw][td->limit_index])
+ return U64_MAX;
+ else
+ return MIN_THROTL_BPS;
+ }
if (td->limit_index == LIMIT_MAX && tg->bps[rw][LIMIT_LOW] &&
tg->bps[rw][LIMIT_LOW] != tg->bps[rw][LIMIT_MAX]) {
@@ -315,10 +329,17 @@ static unsigned int tg_iops_limit(struct throtl_grp *tg, int rw)
if (cgroup_subsys_on_dfl(io_cgrp_subsys) && !blkg->parent)
return UINT_MAX;
+
td = tg->td;
ret = tg->iops[rw][td->limit_index];
- if (ret == 0 && tg->td->limit_index == LIMIT_LOW)
- return tg->iops[rw][LIMIT_MAX];
+ if (ret == 0 && tg->td->limit_index == LIMIT_LOW) {
+ /* intermediate node or bps isn't 0 */
+ if (!list_empty(&blkg->blkcg->css.children) ||
+ tg->bps[rw][td->limit_index])
+ return UINT_MAX;
+ else
+ return MIN_THROTL_IOPS;
+ }
if (td->limit_index == LIMIT_MAX && tg->iops[rw][LIMIT_LOW] &&
tg->iops[rw][LIMIT_LOW] != tg->iops[rw][LIMIT_MAX]) {
@@ -482,6 +503,9 @@ static struct blkg_policy_data *throtl_pd_alloc(gfp_t gfp, int node)
/* LIMIT_LOW will have default value 0 */
tg->latency_target = DFL_LATENCY_TARGET;
+ tg->latency_target_conf = DFL_LATENCY_TARGET;
+ tg->idletime_threshold = DFL_IDLE_THRESHOLD;
+ tg->idletime_threshold_conf = DFL_IDLE_THRESHOLD;
return &tg->pd;
}
@@ -510,8 +534,6 @@ static void throtl_pd_init(struct blkg_policy_data *pd)
if (cgroup_subsys_on_dfl(io_cgrp_subsys) && blkg->parent)
sq->parent_sq = &blkg_to_tg(blkg->parent)->service_queue;
tg->td = td;
-
- tg->idletime_threshold = td->dft_idletime_threshold;
}
/*
@@ -684,7 +706,7 @@ static void throtl_dequeue_tg(struct throtl_grp *tg)
static void throtl_schedule_pending_timer(struct throtl_service_queue *sq,
unsigned long expires)
{
- unsigned long max_expire = jiffies + 8 * sq_to_tg(sq)->td->throtl_slice;
+ unsigned long max_expire = jiffies + 8 * sq_to_td(sq)->throtl_slice;
/*
* Since we are adjusting the throttle limit dynamically, the sleep
@@ -1349,7 +1371,7 @@ static int tg_print_conf_uint(struct seq_file *sf, void *v)
return 0;
}
-static void tg_conf_updated(struct throtl_grp *tg)
+static void tg_conf_updated(struct throtl_grp *tg, bool global)
{
struct throtl_service_queue *sq = &tg->service_queue;
struct cgroup_subsys_state *pos_css;
@@ -1367,8 +1389,26 @@ static void tg_conf_updated(struct throtl_grp *tg)
* restrictions in the whole hierarchy and allows them to bypass
* blk-throttle.
*/
- blkg_for_each_descendant_pre(blkg, pos_css, tg_to_blkg(tg))
- tg_update_has_rules(blkg_to_tg(blkg));
+ blkg_for_each_descendant_pre(blkg, pos_css,
+ global ? tg->td->queue->root_blkg : tg_to_blkg(tg)) {
+ struct throtl_grp *this_tg = blkg_to_tg(blkg);
+ struct throtl_grp *parent_tg;
+
+ tg_update_has_rules(this_tg);
+ /* ignore root/second level */
+ if (!cgroup_subsys_on_dfl(io_cgrp_subsys) || !blkg->parent ||
+ !blkg->parent->parent)
+ continue;
+ parent_tg = blkg_to_tg(blkg->parent);
+ /*
+ * make sure all children has lower idle time threshold and
+ * higher latency target
+ */
+ this_tg->idletime_threshold = min(this_tg->idletime_threshold,
+ parent_tg->idletime_threshold);
+ this_tg->latency_target = max(this_tg->latency_target,
+ parent_tg->latency_target);
+ }
/*
* We're already holding queue_lock and know @tg is valid. Let's
@@ -1413,7 +1453,7 @@ static ssize_t tg_set_conf(struct kernfs_open_file *of,
else
*(unsigned int *)((void *)tg + of_cft(of)->private) = v;
- tg_conf_updated(tg);
+ tg_conf_updated(tg, false);
ret = 0;
out_finish:
blkg_conf_finish(&ctx);
@@ -1497,34 +1537,34 @@ static u64 tg_prfill_limit(struct seq_file *sf, struct blkg_policy_data *pd,
tg->iops_conf[READ][off] == iops_dft &&
tg->iops_conf[WRITE][off] == iops_dft &&
(off != LIMIT_LOW ||
- (tg->idletime_threshold == tg->td->dft_idletime_threshold &&
- tg->latency_target == DFL_LATENCY_TARGET)))
+ (tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD &&
+ tg->latency_target_conf == DFL_LATENCY_TARGET)))
return 0;
- if (tg->bps_conf[READ][off] != bps_dft)
+ if (tg->bps_conf[READ][off] != U64_MAX)
snprintf(bufs[0], sizeof(bufs[0]), "%llu",
tg->bps_conf[READ][off]);
- if (tg->bps_conf[WRITE][off] != bps_dft)
+ if (tg->bps_conf[WRITE][off] != U64_MAX)
snprintf(bufs[1], sizeof(bufs[1]), "%llu",
tg->bps_conf[WRITE][off]);
- if (tg->iops_conf[READ][off] != iops_dft)
+ if (tg->iops_conf[READ][off] != UINT_MAX)
snprintf(bufs[2], sizeof(bufs[2]), "%u",
tg->iops_conf[READ][off]);
- if (tg->iops_conf[WRITE][off] != iops_dft)
+ if (tg->iops_conf[WRITE][off] != UINT_MAX)
snprintf(bufs[3], sizeof(bufs[3]), "%u",
tg->iops_conf[WRITE][off]);
if (off == LIMIT_LOW) {
- if (tg->idletime_threshold == ULONG_MAX)
+ if (tg->idletime_threshold_conf == ULONG_MAX)
strcpy(idle_time, " idle=max");
else
snprintf(idle_time, sizeof(idle_time), " idle=%lu",
- tg->idletime_threshold);
+ tg->idletime_threshold_conf);
- if (tg->latency_target == ULONG_MAX)
+ if (tg->latency_target_conf == ULONG_MAX)
strcpy(latency_time, " latency=max");
else
snprintf(latency_time, sizeof(latency_time),
- " latency=%lu", tg->latency_target);
+ " latency=%lu", tg->latency_target_conf);
}
seq_printf(sf, "%s rbps=%s wbps=%s riops=%s wiops=%s%s%s\n",
@@ -1563,8 +1603,8 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of,
v[2] = tg->iops_conf[READ][index];
v[3] = tg->iops_conf[WRITE][index];
- idle_time = tg->idletime_threshold;
- latency_time = tg->latency_target;
+ idle_time = tg->idletime_threshold_conf;
+ latency_time = tg->latency_target_conf;
while (true) {
char tok[27]; /* wiops=18446744073709551616 */
char *p;
@@ -1623,17 +1663,33 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of,
tg->iops_conf[READ][LIMIT_MAX]);
tg->iops[WRITE][LIMIT_LOW] = min(tg->iops_conf[WRITE][LIMIT_LOW],
tg->iops_conf[WRITE][LIMIT_MAX]);
+ tg->idletime_threshold_conf = idle_time;
+ tg->latency_target_conf = latency_time;
+
+ /* force user to configure all settings for low limit */
+ if (!(tg->bps[READ][LIMIT_LOW] || tg->iops[READ][LIMIT_LOW] ||
+ tg->bps[WRITE][LIMIT_LOW] || tg->iops[WRITE][LIMIT_LOW]) ||
+ tg->idletime_threshold_conf == DFL_IDLE_THRESHOLD ||
+ tg->latency_target_conf == DFL_LATENCY_TARGET) {
+ tg->bps[READ][LIMIT_LOW] = 0;
+ tg->bps[WRITE][LIMIT_LOW] = 0;
+ tg->iops[READ][LIMIT_LOW] = 0;
+ tg->iops[WRITE][LIMIT_LOW] = 0;
+ tg->idletime_threshold = DFL_IDLE_THRESHOLD;
+ tg->latency_target = DFL_LATENCY_TARGET;
+ } else if (index == LIMIT_LOW) {
+ tg->idletime_threshold = tg->idletime_threshold_conf;
+ tg->latency_target = tg->latency_target_conf;
+ }
- if (index == LIMIT_LOW) {
- blk_throtl_update_limit_valid(tg->td);
- if (tg->td->limit_valid[LIMIT_LOW])
+ blk_throtl_update_limit_valid(tg->td);
+ if (tg->td->limit_valid[LIMIT_LOW]) {
+ if (index == LIMIT_LOW)
tg->td->limit_index = LIMIT_LOW;
- tg->idletime_threshold = (idle_time == ULONG_MAX) ?
- ULONG_MAX : idle_time;
- tg->latency_target = (latency_time == ULONG_MAX) ?
- ULONG_MAX : latency_time;
- }
- tg_conf_updated(tg);
+ } else
+ tg->td->limit_index = LIMIT_MAX;
+ tg_conf_updated(tg, index == LIMIT_LOW &&
+ tg->td->limit_valid[LIMIT_LOW]);
ret = 0;
out_finish:
blkg_conf_finish(&ctx);
@@ -1722,17 +1778,25 @@ static bool throtl_tg_is_idle(struct throtl_grp *tg)
/*
* cgroup is idle if:
* - single idle is too long, longer than a fixed value (in case user
- * configure a too big threshold) or 4 times of slice
+ * configure a too big threshold) or 4 times of idletime threshold
* - average think time is more than threshold
* - IO latency is largely below threshold
*/
- unsigned long time = jiffies_to_usecs(4 * tg->td->throtl_slice);
-
- time = min_t(unsigned long, MAX_IDLE_TIME, time);
- return (ktime_get_ns() >> 10) - tg->last_finish_time > time ||
- tg->avg_idletime > tg->idletime_threshold ||
- (tg->latency_target && tg->bio_cnt &&
+ unsigned long time;
+ bool ret;
+
+ time = min_t(unsigned long, MAX_IDLE_TIME, 4 * tg->idletime_threshold);
+ ret = tg->latency_target == DFL_LATENCY_TARGET ||
+ tg->idletime_threshold == DFL_IDLE_THRESHOLD ||
+ (ktime_get_ns() >> 10) - tg->last_finish_time > time ||
+ tg->avg_idletime > tg->idletime_threshold ||
+ (tg->latency_target && tg->bio_cnt &&
tg->bad_bio_cnt * 5 < tg->bio_cnt);
+ throtl_log(&tg->service_queue,
+ "avg_idle=%ld, idle_threshold=%ld, bad_bio=%d, total_bio=%d, is_idle=%d, scale=%d",
+ tg->avg_idletime, tg->idletime_threshold, tg->bad_bio_cnt,
+ tg->bio_cnt, ret, tg->td->scale);
+ return ret;
}
static bool throtl_tg_can_upgrade(struct throtl_grp *tg)
@@ -1828,6 +1892,7 @@ static void throtl_upgrade_state(struct throtl_data *td)
struct cgroup_subsys_state *pos_css;
struct blkcg_gq *blkg;
+ throtl_log(&td->service_queue, "upgrade to max");
td->limit_index = LIMIT_MAX;
td->low_upgrade_time = jiffies;
td->scale = 0;
@@ -1850,6 +1915,7 @@ static void throtl_downgrade_state(struct throtl_data *td, int new)
{
td->scale /= 2;
+ throtl_log(&td->service_queue, "downgrade, scale %d", td->scale);
if (td->scale) {
td->low_upgrade_time = jiffies - td->scale * td->throtl_slice;
return;
@@ -2023,6 +2089,11 @@ static void throtl_update_latency_buckets(struct throtl_data *td)
td->avg_buckets[i].valid = true;
last_latency = td->avg_buckets[i].latency;
}
+
+ for (i = 0; i < LATENCY_BUCKET_SIZE; i++)
+ throtl_log(&td->service_queue,
+ "Latency bucket %d: latency=%ld, valid=%d", i,
+ td->avg_buckets[i].latency, td->avg_buckets[i].valid);
}
#else
static inline void throtl_update_latency_buckets(struct throtl_data *td)
@@ -2218,7 +2289,7 @@ void blk_throtl_bio_endio(struct bio *bio)
throtl_track_latency(tg->td, blk_stat_size(&bio->bi_issue_stat),
bio_op(bio), lat);
- if (tg->latency_target) {
+ if (tg->latency_target && lat >= tg->td->filtered_latency) {
int bucket;
unsigned int threshold;
@@ -2354,18 +2425,19 @@ void blk_throtl_exit(struct request_queue *q)
void blk_throtl_register_queue(struct request_queue *q)
{
struct throtl_data *td;
- struct cgroup_subsys_state *pos_css;
- struct blkcg_gq *blkg;
+ int i;
td = q->td;
BUG_ON(!td);
if (blk_queue_nonrot(q)) {
td->throtl_slice = DFL_THROTL_SLICE_SSD;
- td->dft_idletime_threshold = DFL_IDLE_THRESHOLD_SSD;
+ td->filtered_latency = LATENCY_FILTERED_SSD;
} else {
td->throtl_slice = DFL_THROTL_SLICE_HD;
- td->dft_idletime_threshold = DFL_IDLE_THRESHOLD_HD;
+ td->filtered_latency = LATENCY_FILTERED_HD;
+ for (i = 0; i < LATENCY_BUCKET_SIZE; i++)
+ td->avg_buckets[i].latency = DFL_HD_BASELINE_LATENCY;
}
#ifndef CONFIG_BLK_DEV_THROTTLING_LOW
/* if no low limit, use previous default */
@@ -2375,18 +2447,6 @@ void blk_throtl_register_queue(struct request_queue *q)
td->track_bio_latency = !q->mq_ops && !q->request_fn;
if (!td->track_bio_latency)
blk_stat_enable_accounting(q);
-
- /*
- * some tg are created before queue is fully initialized, eg, nonrot
- * isn't initialized yet
- */
- rcu_read_lock();
- blkg_for_each_descendant_post(blkg, pos_css, q->root_blkg) {
- struct throtl_grp *tg = blkg_to_tg(blkg);
-
- tg->idletime_threshold = td->dft_idletime_threshold;
- }
- rcu_read_unlock();
}
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
diff --git a/block/blk.h b/block/blk.h
index 2ed70228e44fc..83c8e1100525f 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -59,7 +59,7 @@ void blk_free_flush_queue(struct blk_flush_queue *q);
int blk_init_rl(struct request_list *rl, struct request_queue *q,
gfp_t gfp_mask);
-void blk_exit_rl(struct request_list *rl);
+void blk_exit_rl(struct request_queue *q, struct request_list *rl);
void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
struct bio *bio);
void blk_queue_bypass_start(struct request_queue *q);
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index da69b079725fb..b7e9c7feeab2a 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -38,9 +38,13 @@ static const u64 cfq_target_latency = (u64)NSEC_PER_SEC * 3/10; /* 300 ms */
static const int cfq_hist_divisor = 4;
/*
- * offset from end of service tree
+ * offset from end of queue service tree for idle class
*/
#define CFQ_IDLE_DELAY (NSEC_PER_SEC / 5)
+/* offset from end of group service tree under time slice mode */
+#define CFQ_SLICE_MODE_GROUP_DELAY (NSEC_PER_SEC / 5)
+/* offset from end of group service under IOPS mode */
+#define CFQ_IOPS_MODE_GROUP_DELAY (HZ / 5)
/*
* below this threshold, we consider thinktime immediate
@@ -1362,6 +1366,14 @@ cfq_group_service_tree_add(struct cfq_rb_root *st, struct cfq_group *cfqg)
cfqg->vfraction = max_t(unsigned, vfr, 1);
}
+static inline u64 cfq_get_cfqg_vdisktime_delay(struct cfq_data *cfqd)
+{
+ if (!iops_mode(cfqd))
+ return CFQ_SLICE_MODE_GROUP_DELAY;
+ else
+ return CFQ_IOPS_MODE_GROUP_DELAY;
+}
+
static void
cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
{
@@ -1381,7 +1393,8 @@ cfq_group_notify_queue_add(struct cfq_data *cfqd, struct cfq_group *cfqg)
n = rb_last(&st->rb);
if (n) {
__cfqg = rb_entry_cfqg(n);
- cfqg->vdisktime = __cfqg->vdisktime + CFQ_IDLE_DELAY;
+ cfqg->vdisktime = __cfqg->vdisktime +
+ cfq_get_cfqg_vdisktime_delay(cfqd);
} else
cfqg->vdisktime = st->min_vdisktime;
cfq_group_service_tree_add(st, cfqg);
diff --git a/block/partition-generic.c b/block/partition-generic.c
index ff07b9143ca45..c5ec8246e25e1 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -320,8 +320,10 @@ struct hd_struct *add_partition(struct gendisk *disk, int partno,
if (info) {
struct partition_meta_info *pinfo = alloc_part_info(disk);
- if (!pinfo)
+ if (!pinfo) {
+ err = -ENOMEM;
goto out_free_stats;
+ }
memcpy(pinfo, info, sizeof(*info));
p->info = pinfo;
}
diff --git a/block/partitions/msdos.c b/block/partitions/msdos.c
index 93e7c1b32eddd..5610cd537da78 100644
--- a/block/partitions/msdos.c
+++ b/block/partitions/msdos.c
@@ -300,6 +300,8 @@ static void parse_bsd(struct parsed_partitions *state,
continue;
bsd_start = le32_to_cpu(p->p_offset);
bsd_size = le32_to_cpu(p->p_size);
+ if (memcmp(flavour, "bsd\0", 4) == 0)
+ bsd_start += offset;
if (offset == bsd_start && size == bsd_size)
/* full parent partition, we have it already */
continue;
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-30 11:43:49 +0000