+// SPDX-License-Identifier: GPL-2.0
/*
* Block multiqueue core code
*
void blk_freeze_queue_start(struct request_queue *q)
{
- int freeze_depth;
-
- freeze_depth = atomic_inc_return(&q->mq_freeze_depth);
- if (freeze_depth == 1) {
+ mutex_lock(&q->mq_freeze_lock);
+ if (++q->mq_freeze_depth == 1) {
percpu_ref_kill(&q->q_usage_counter);
+ mutex_unlock(&q->mq_freeze_lock);
if (queue_is_mq(q))
blk_mq_run_hw_queues(q, false);
+ } else {
+ mutex_unlock(&q->mq_freeze_lock);
}
}
EXPORT_SYMBOL_GPL(blk_freeze_queue_start);
void blk_mq_unfreeze_queue(struct request_queue *q)
{
- int freeze_depth;
-
- freeze_depth = atomic_dec_return(&q->mq_freeze_depth);
- WARN_ON_ONCE(freeze_depth < 0);
- if (!freeze_depth) {
+ mutex_lock(&q->mq_freeze_lock);
+ q->mq_freeze_depth--;
+ WARN_ON_ONCE(q->mq_freeze_depth < 0);
+ if (!q->mq_freeze_depth) {
percpu_ref_resurrect(&q->q_usage_counter);
wake_up_all(&q->mq_freeze_wq);
}
+ mutex_unlock(&q->mq_freeze_lock);
}
EXPORT_SYMBOL_GPL(blk_mq_unfreeze_queue);
struct elevator_queue *e = q->elevator;
struct request *rq;
unsigned int tag;
- bool put_ctx_on_error = false;
+ bool clear_ctx_on_error = false;
blk_queue_enter_live(q);
data->q = q;
if (likely(!data->ctx)) {
data->ctx = blk_mq_get_ctx(q);
- put_ctx_on_error = true;
+ clear_ctx_on_error = true;
}
if (likely(!data->hctx))
data->hctx = blk_mq_map_queue(q, data->cmd_flags,
tag = blk_mq_get_tag(data);
if (tag == BLK_MQ_TAG_FAIL) {
- if (put_ctx_on_error) {
- blk_mq_put_ctx(data->ctx);
+ if (clear_ctx_on_error)
data->ctx = NULL;
- }
blk_queue_exit(q);
return NULL;
}
if (!rq)
return ERR_PTR(-EWOULDBLOCK);
- blk_mq_put_ctx(alloc_data.ctx);
-
rq->__data_len = 0;
rq->__sector = (sector_t) -1;
rq->bio = rq->biotail = NULL;
}
}
-static void blk_mq_bio_to_request(struct request *rq, struct bio *bio)
+static void blk_mq_bio_to_request(struct request *rq, struct bio *bio,
+ unsigned int nr_segs)
{
- blk_init_request_from_bio(rq, bio);
+ if (bio->bi_opf & REQ_RAHEAD)
+ rq->cmd_flags |= REQ_FAILFAST_MASK;
+
+ rq->__sector = bio->bi_iter.bi_sector;
+ rq->write_hint = bio->bi_write_hint;
+ blk_rq_bio_prep(rq, bio, nr_segs);
blk_account_io_start(rq, true);
}
struct request *rq;
struct blk_plug *plug;
struct request *same_queue_rq = NULL;
+ unsigned int nr_segs;
blk_qc_t cookie;
blk_queue_bounce(q, &bio);
-
- blk_queue_split(q, &bio);
+ __blk_queue_split(q, &bio, &nr_segs);
if (!bio_integrity_prep(bio))
return BLK_QC_T_NONE;
if (!is_flush_fua && !blk_queue_nomerges(q) &&
- blk_attempt_plug_merge(q, bio, &same_queue_rq))
+ blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq))
return BLK_QC_T_NONE;
- if (blk_mq_sched_bio_merge(q, bio))
+ if (blk_mq_sched_bio_merge(q, bio, nr_segs))
return BLK_QC_T_NONE;
rq_qos_throttle(q, bio);
cookie = request_to_qc_t(data.hctx, rq);
+ blk_mq_bio_to_request(rq, bio, nr_segs);
+
plug = current->plug;
if (unlikely(is_flush_fua)) {
- blk_mq_put_ctx(data.ctx);
- blk_mq_bio_to_request(rq, bio);
-
/* bypass scheduler for flush rq */
blk_insert_flush(rq);
blk_mq_run_hw_queue(data.hctx, true);
unsigned int request_count = plug->rq_count;
struct request *last = NULL;
- blk_mq_put_ctx(data.ctx);
- blk_mq_bio_to_request(rq, bio);
-
if (!request_count)
trace_block_plug(q);
else
blk_add_rq_to_plug(plug, rq);
} else if (plug && !blk_queue_nomerges(q)) {
- blk_mq_bio_to_request(rq, bio);
-
/*
* We do limited plugging. If the bio can be merged, do that.
* Otherwise the existing request in the plug list will be
blk_add_rq_to_plug(plug, rq);
trace_block_plug(q);
- blk_mq_put_ctx(data.ctx);
-
if (same_queue_rq) {
data.hctx = same_queue_rq->mq_hctx;
trace_block_unplug(q, 1, true);
}
} else if ((q->nr_hw_queues > 1 && is_sync) || (!q->elevator &&
!data.hctx->dispatch_busy)) {
- blk_mq_put_ctx(data.ctx);
- blk_mq_bio_to_request(rq, bio);
blk_mq_try_issue_directly(data.hctx, rq, &cookie);
} else {
- blk_mq_put_ctx(data.ctx);
- blk_mq_bio_to_request(rq, bio);
blk_mq_sched_insert_request(rq, false, true, true);
}
list_del_init(&page->lru);
/*
* Remove kmemleak object previously allocated in
- * blk_mq_init_rq_map().
+ * blk_mq_alloc_rqs().
*/
kmemleak_free(page_address(page));
__free_pages(page, page->private);
if (set->ops->exit_hctx)
set->ops->exit_hctx(hctx, hctx_idx);
- if (hctx->flags & BLK_MQ_F_BLOCKING)
- cleanup_srcu_struct(hctx->srcu);
-
blk_mq_remove_cpuhp(hctx);
- blk_free_flush_queue(hctx->fq);
- sbitmap_free(&hctx->ctx_map);
+
+ spin_lock(&q->unused_hctx_lock);
+ list_add(&hctx->hctx_list, &q->unused_hctx_list);
+ spin_unlock(&q->unused_hctx_lock);
}
static void blk_mq_exit_hw_queues(struct request_queue *q,
}
}
+static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
+{
+ int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);
+
+ BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, srcu),
+ __alignof__(struct blk_mq_hw_ctx)) !=
+ sizeof(struct blk_mq_hw_ctx));
+
+ if (tag_set->flags & BLK_MQ_F_BLOCKING)
+ hw_ctx_size += sizeof(struct srcu_struct);
+
+ return hw_ctx_size;
+}
+
static int blk_mq_init_hctx(struct request_queue *q,
struct blk_mq_tag_set *set,
struct blk_mq_hw_ctx *hctx, unsigned hctx_idx)
{
- int node;
+ hctx->queue_num = hctx_idx;
- node = hctx->numa_node;
+ cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead);
+
+ hctx->tags = set->tags[hctx_idx];
+
+ if (set->ops->init_hctx &&
+ set->ops->init_hctx(hctx, set->driver_data, hctx_idx))
+ goto unregister_cpu_notifier;
+
+ if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx,
+ hctx->numa_node))
+ goto exit_hctx;
+ return 0;
+
+ exit_hctx:
+ if (set->ops->exit_hctx)
+ set->ops->exit_hctx(hctx, hctx_idx);
+ unregister_cpu_notifier:
+ blk_mq_remove_cpuhp(hctx);
+ return -1;
+}
+
+static struct blk_mq_hw_ctx *
+blk_mq_alloc_hctx(struct request_queue *q, struct blk_mq_tag_set *set,
+ int node)
+{
+ struct blk_mq_hw_ctx *hctx;
+ gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY;
+
+ hctx = kzalloc_node(blk_mq_hw_ctx_size(set), gfp, node);
+ if (!hctx)
+ goto fail_alloc_hctx;
+
+ if (!zalloc_cpumask_var_node(&hctx->cpumask, gfp, node))
+ goto free_hctx;
+
+ atomic_set(&hctx->nr_active, 0);
if (node == NUMA_NO_NODE)
- node = hctx->numa_node = set->numa_node;
+ node = set->numa_node;
+ hctx->numa_node = node;
INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn);
spin_lock_init(&hctx->lock);
hctx->queue = q;
hctx->flags = set->flags & ~BLK_MQ_F_TAG_SHARED;
- cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead);
-
- hctx->tags = set->tags[hctx_idx];
+ INIT_LIST_HEAD(&hctx->hctx_list);
/*
* Allocate space for all possible cpus to avoid allocation at
* runtime
*/
hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node);
+ gfp, node);
if (!hctx->ctxs)
- goto unregister_cpu_notifier;
+ goto free_cpumask;
if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node))
+ gfp, node))
goto free_ctxs;
-
hctx->nr_ctx = 0;
spin_lock_init(&hctx->dispatch_wait_lock);
init_waitqueue_func_entry(&hctx->dispatch_wait, blk_mq_dispatch_wake);
INIT_LIST_HEAD(&hctx->dispatch_wait.entry);
- if (set->ops->init_hctx &&
- set->ops->init_hctx(hctx, set->driver_data, hctx_idx))
- goto free_bitmap;
-
hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size,
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY);
+ gfp);
if (!hctx->fq)
- goto exit_hctx;
-
- if (blk_mq_init_request(set, hctx->fq->flush_rq, hctx_idx, node))
- goto free_fq;
+ goto free_bitmap;
if (hctx->flags & BLK_MQ_F_BLOCKING)
init_srcu_struct(hctx->srcu);
+ blk_mq_hctx_kobj_init(hctx);
- return 0;
+ return hctx;
- free_fq:
- blk_free_flush_queue(hctx->fq);
- exit_hctx:
- if (set->ops->exit_hctx)
- set->ops->exit_hctx(hctx, hctx_idx);
free_bitmap:
sbitmap_free(&hctx->ctx_map);
free_ctxs:
kfree(hctx->ctxs);
- unregister_cpu_notifier:
- blk_mq_remove_cpuhp(hctx);
- return -1;
+ free_cpumask:
+ free_cpumask_var(hctx->cpumask);
+ free_hctx:
+ kfree(hctx);
+ fail_alloc_hctx:
+ return NULL;
}
static void blk_mq_init_cpu_queues(struct request_queue *q,
*/
void blk_mq_release(struct request_queue *q)
{
- struct blk_mq_hw_ctx *hctx;
- unsigned int i;
+ struct blk_mq_hw_ctx *hctx, *next;
+ int i;
- /* hctx kobj stays in hctx */
- queue_for_each_hw_ctx(q, hctx, i) {
- if (!hctx)
- continue;
+ cancel_delayed_work_sync(&q->requeue_work);
+
+ queue_for_each_hw_ctx(q, hctx, i)
+ WARN_ON_ONCE(hctx && list_empty(&hctx->hctx_list));
+
+ /* all hctx are in .unused_hctx_list now */
+ list_for_each_entry_safe(hctx, next, &q->unused_hctx_list, hctx_list) {
+ list_del_init(&hctx->hctx_list);
kobject_put(&hctx->kobj);
}
}
EXPORT_SYMBOL(blk_mq_init_sq_queue);
-static int blk_mq_hw_ctx_size(struct blk_mq_tag_set *tag_set)
-{
- int hw_ctx_size = sizeof(struct blk_mq_hw_ctx);
-
- BUILD_BUG_ON(ALIGN(offsetof(struct blk_mq_hw_ctx, srcu),
- __alignof__(struct blk_mq_hw_ctx)) !=
- sizeof(struct blk_mq_hw_ctx));
-
- if (tag_set->flags & BLK_MQ_F_BLOCKING)
- hw_ctx_size += sizeof(struct srcu_struct);
-
- return hw_ctx_size;
-}
-
static struct blk_mq_hw_ctx *blk_mq_alloc_and_init_hctx(
struct blk_mq_tag_set *set, struct request_queue *q,
int hctx_idx, int node)
{
- struct blk_mq_hw_ctx *hctx;
-
- hctx = kzalloc_node(blk_mq_hw_ctx_size(set),
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
- node);
- if (!hctx)
- return NULL;
+ struct blk_mq_hw_ctx *hctx = NULL, *tmp;
- if (!zalloc_cpumask_var_node(&hctx->cpumask,
- GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
- node)) {
- kfree(hctx);
- return NULL;
+ /* reuse dead hctx first */
+ spin_lock(&q->unused_hctx_lock);
+ list_for_each_entry(tmp, &q->unused_hctx_list, hctx_list) {
+ if (tmp->numa_node == node) {
+ hctx = tmp;
+ break;
+ }
}
+ if (hctx)
+ list_del_init(&hctx->hctx_list);
+ spin_unlock(&q->unused_hctx_lock);
- atomic_set(&hctx->nr_active, 0);
- hctx->numa_node = node;
- hctx->queue_num = hctx_idx;
+ if (!hctx)
+ hctx = blk_mq_alloc_hctx(q, set, node);
+ if (!hctx)
+ goto fail;
- if (blk_mq_init_hctx(q, set, hctx, hctx_idx)) {
- free_cpumask_var(hctx->cpumask);
- kfree(hctx);
- return NULL;
- }
- blk_mq_hctx_kobj_init(hctx);
+ if (blk_mq_init_hctx(q, set, hctx, hctx_idx))
+ goto free_hctx;
return hctx;
+
+ free_hctx:
+ kobject_put(&hctx->kobj);
+ fail:
+ return NULL;
}
static void blk_mq_realloc_hw_ctxs(struct blk_mq_tag_set *set,
hctx = blk_mq_alloc_and_init_hctx(set, q, i, node);
if (hctx) {
- if (hctxs[i]) {
+ if (hctxs[i])
blk_mq_exit_hctx(q, set, hctxs[i], i);
- kobject_put(&hctxs[i]->kobj);
- }
hctxs[i] = hctx;
} else {
if (hctxs[i])
if (hctx->tags)
blk_mq_free_map_and_requests(set, j);
blk_mq_exit_hctx(q, set, hctx, j);
- kobject_put(&hctx->kobj);
hctxs[j] = NULL;
-
}
}
mutex_unlock(&q->sysfs_lock);
goto err_exit;
if (blk_mq_alloc_ctxs(q))
- goto err_exit;
+ goto err_poll;
/* init q->mq_kobj and sw queues' kobjects */
blk_mq_sysfs_init(q);
if (!q->queue_hw_ctx)
goto err_sys_init;
+ INIT_LIST_HEAD(&q->unused_hctx_list);
+ spin_lock_init(&q->unused_hctx_lock);
+
blk_mq_realloc_hw_ctxs(set, q);
if (!q->nr_hw_queues)
goto err_hctxs;
kfree(q->queue_hw_ctx);
err_sys_init:
blk_mq_sysfs_deinit(q);
+err_poll:
+ blk_stat_free_callback(q->poll_cb);
+ q->poll_cb = NULL;
err_exit:
q->mq_ops = NULL;
return ERR_PTR(-ENOMEM);
}
EXPORT_SYMBOL(blk_mq_init_allocated_queue);
-void blk_mq_free_queue(struct request_queue *q)
+/* tags can _not_ be used after returning from blk_mq_exit_queue */
+void blk_mq_exit_queue(struct request_queue *q)
{
struct blk_mq_tag_set *set = q->tag_set;