rq->tag = -1;
rq->internal_tag = tag;
} else {
- if (blk_mq_tag_busy(data->hctx)) {
+ if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) {
rq->rq_flags = RQF_MQ_INFLIGHT;
atomic_inc(&data->hctx->nr_active);
}
*/
if (!op_is_flush(op) && e->type->ops.mq.limit_depth)
e->type->ops.mq.limit_depth(op, data);
+ } else {
+ blk_mq_tag_busy(data->hctx);
}
tag = blk_mq_get_tag(data);
put_cpu();
}
+static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx)
+{
+ if (!(hctx->flags & BLK_MQ_F_BLOCKING))
+ rcu_read_unlock();
+ else
+ srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx);
+}
+
+static void hctx_lock(struct blk_mq_hw_ctx *hctx, int *srcu_idx)
+{
+ if (!(hctx->flags & BLK_MQ_F_BLOCKING))
+ rcu_read_lock();
+ else
+ *srcu_idx = srcu_read_lock(hctx->queue_rq_srcu);
+}
+
/**
* blk_mq_complete_request - end I/O on a request
* @rq: the request being processed
spin_unlock_irq(&q->requeue_lock);
list_for_each_entry_safe(rq, next, &rq_list, queuelist) {
- if (!(rq->rq_flags & RQF_SOFTBARRIER))
+ if (!(rq->rq_flags & (RQF_SOFTBARRIER | RQF_DONTPREP)))
continue;
rq->rq_flags &= ~RQF_SOFTBARRIER;
list_del_init(&rq->queuelist);
- blk_mq_sched_insert_request(rq, true, false, false, true);
+ /*
+ * If RQF_DONTPREP, rq has contained some driver specific
+ * data, so insert it to hctx dispatch list to avoid any
+ * merge.
+ */
+ if (rq->rq_flags & RQF_DONTPREP)
+ blk_mq_request_bypass_insert(rq, false);
+ else
+ blk_mq_sched_insert_request(rq, true, false, false, true);
}
while (!list_empty(&rq_list)) {
.hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu),
.flags = wait ? 0 : BLK_MQ_REQ_NOWAIT,
};
+ bool shared;
might_sleep_if(wait);
if (blk_mq_tag_is_reserved(data.hctx->sched_tags, rq->internal_tag))
data.flags |= BLK_MQ_REQ_RESERVED;
+ shared = blk_mq_tag_busy(data.hctx);
rq->tag = blk_mq_get_tag(&data);
if (rq->tag >= 0) {
- if (blk_mq_tag_busy(data.hctx)) {
+ if (shared) {
rq->rq_flags |= RQF_MQ_INFLIGHT;
atomic_inc(&data.hctx->nr_active);
}
*/
WARN_ON_ONCE(in_interrupt());
- if (!(hctx->flags & BLK_MQ_F_BLOCKING)) {
- rcu_read_lock();
- blk_mq_sched_dispatch_requests(hctx);
- rcu_read_unlock();
- } else {
- might_sleep();
+ might_sleep_if(hctx->flags & BLK_MQ_F_BLOCKING);
- srcu_idx = srcu_read_lock(hctx->queue_rq_srcu);
- blk_mq_sched_dispatch_requests(hctx);
- srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx);
- }
+ hctx_lock(hctx, &srcu_idx);
+ blk_mq_sched_dispatch_requests(hctx);
+ hctx_unlock(hctx, srcu_idx);
}
static inline int blk_mq_first_mapped_cpu(struct blk_mq_hw_ctx *hctx)
bool blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
{
- if (blk_mq_hctx_has_pending(hctx)) {
+ int srcu_idx;
+ bool need_run;
+
+ /*
+ * When queue is quiesced, we may be switching io scheduler, or
+ * updating nr_hw_queues, or other things, and we can't run queue
+ * any more, even __blk_mq_hctx_has_pending() can't be called safely.
+ *
+ * And queue will be rerun in blk_mq_unquiesce_queue() if it is
+ * quiesced.
+ */
+ hctx_lock(hctx, &srcu_idx);
+ need_run = !blk_queue_quiesced(hctx->queue) &&
+ blk_mq_hctx_has_pending(hctx);
+ hctx_unlock(hctx, srcu_idx);
+
+ if (need_run) {
__blk_mq_delay_run_hw_queue(hctx, async, 0);
return true;
}
BUG_ON(!rq->q);
if (rq->mq_ctx != this_ctx) {
if (this_ctx) {
- trace_block_unplug(this_q, depth, from_schedule);
+ trace_block_unplug(this_q, depth, !from_schedule);
blk_mq_sched_insert_requests(this_q, this_ctx,
&ctx_list,
from_schedule);
* on 'ctx_list'. Do those.
*/
if (this_ctx) {
- trace_block_unplug(this_q, depth, from_schedule);
+ trace_block_unplug(this_q, depth, !from_schedule);
blk_mq_sched_insert_requests(this_q, this_ctx, &ctx_list,
from_schedule);
}
static void __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
struct request *rq,
- blk_qc_t *cookie, bool may_sleep)
+ blk_qc_t *cookie)
{
struct request_queue *q = rq->q;
struct blk_mq_queue_data bd = {
}
insert:
- blk_mq_sched_insert_request(rq, false, run_queue, false, may_sleep);
+ blk_mq_sched_insert_request(rq, false, run_queue, false,
+ hctx->flags & BLK_MQ_F_BLOCKING);
}
static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
struct request *rq, blk_qc_t *cookie)
{
- if (!(hctx->flags & BLK_MQ_F_BLOCKING)) {
- rcu_read_lock();
- __blk_mq_try_issue_directly(hctx, rq, cookie, false);
- rcu_read_unlock();
- } else {
- unsigned int srcu_idx;
+ int srcu_idx;
- might_sleep();
+ might_sleep_if(hctx->flags & BLK_MQ_F_BLOCKING);
- srcu_idx = srcu_read_lock(hctx->queue_rq_srcu);
- __blk_mq_try_issue_directly(hctx, rq, cookie, true);
- srcu_read_unlock(hctx->queue_rq_srcu, srcu_idx);
- }
+ hctx_lock(hctx, &srcu_idx);
+ __blk_mq_try_issue_directly(hctx, rq, cookie);
+ hctx_unlock(hctx, srcu_idx);
}
static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)
if (set->ops->exit_hctx)
set->ops->exit_hctx(hctx, hctx_idx);
- if (hctx->flags & BLK_MQ_F_BLOCKING)
- cleanup_srcu_struct(hctx->queue_rq_srcu);
-
blk_mq_remove_cpuhp(hctx);
- blk_free_flush_queue(hctx->fq);
- sbitmap_free(&hctx->ctx_map);
}
static void blk_mq_exit_hw_queues(struct request_queue *q,
* runtime
*/
hctx->ctxs = kmalloc_array_node(nr_cpu_ids, sizeof(void *),
- GFP_KERNEL, node);
+ GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node);
if (!hctx->ctxs)
goto unregister_cpu_notifier;
- if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8), GFP_KERNEL,
- node))
+ if (sbitmap_init_node(&hctx->ctx_map, nr_cpu_ids, ilog2(8),
+ GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY, node))
goto free_ctxs;
hctx->nr_ctx = 0;
if (blk_mq_sched_init_hctx(q, hctx, hctx_idx))
goto exit_hctx;
- hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size);
+ hctx->fq = blk_alloc_flush_queue(q, hctx->numa_node, set->cmd_size,
+ GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY);
if (!hctx->fq)
goto sched_exit_hctx;
return 0;
free_fq:
- kfree(hctx->fq);
+ blk_free_flush_queue(hctx->fq);
sched_exit_hctx:
blk_mq_sched_exit_hctx(q, hctx, hctx_idx);
exit_hctx:
mutex_lock(&set->tag_list_lock);
list_del_rcu(&q->tag_set_list);
- INIT_LIST_HEAD(&q->tag_set_list);
if (list_is_singular(&set->tag_list)) {
/* just transitioned to unshared */
set->flags &= ~BLK_MQ_F_TAG_SHARED;
blk_mq_update_tag_set_depth(set, false);
}
mutex_unlock(&set->tag_list_lock);
-
synchronize_rcu();
+ INIT_LIST_HEAD(&q->tag_set_list);
}
static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set,
node = blk_mq_hw_queue_to_node(q->mq_map, i);
hctxs[i] = kzalloc_node(blk_mq_hw_ctx_size(set),
- GFP_KERNEL, node);
+ GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
+ node);
if (!hctxs[i])
break;
- if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask, GFP_KERNEL,
- node)) {
+ if (!zalloc_cpumask_var_node(&hctxs[i]->cpumask,
+ GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY,
+ node)) {
kfree(hctxs[i]);
hctxs[i] = NULL;
break;
}
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;
if (!set)
return -EINVAL;
+ if (q->nr_requests == nr)
+ return 0;
+
blk_mq_freeze_queue(q);
+ blk_mq_quiesce_queue(q);
ret = 0;
queue_for_each_hw_ctx(q, hctx, i) {
if (!ret)
q->nr_requests = nr;
+ blk_mq_unquiesce_queue(q);
blk_mq_unfreeze_queue(q);
return ret;