summaryrefslogtreecommitdiffstats
path: root/block/blk-mq.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /block/blk-mq.h
parentInitial commit. (diff)
downloadlinux-upstream/5.10.209.tar.xz
linux-upstream/5.10.209.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'block/blk-mq.h')
-rw-r--r--block/blk-mq.h327
1 files changed, 327 insertions, 0 deletions
diff --git a/block/blk-mq.h b/block/blk-mq.h
new file mode 100644
index 000000000..f792a0920
--- /dev/null
+++ b/block/blk-mq.h
@@ -0,0 +1,327 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef INT_BLK_MQ_H
+#define INT_BLK_MQ_H
+
+#include "blk-stat.h"
+#include "blk-mq-tag.h"
+
+struct blk_mq_tag_set;
+
+struct blk_mq_ctxs {
+ struct kobject kobj;
+ struct blk_mq_ctx __percpu *queue_ctx;
+};
+
+/**
+ * struct blk_mq_ctx - State for a software queue facing the submitting CPUs
+ */
+struct blk_mq_ctx {
+ struct {
+ spinlock_t lock;
+ struct list_head rq_lists[HCTX_MAX_TYPES];
+ } ____cacheline_aligned_in_smp;
+
+ unsigned int cpu;
+ unsigned short index_hw[HCTX_MAX_TYPES];
+ struct blk_mq_hw_ctx *hctxs[HCTX_MAX_TYPES];
+
+ /* incremented at dispatch time */
+ unsigned long rq_dispatched[2];
+ unsigned long rq_merged;
+
+ /* incremented at completion time */
+ unsigned long ____cacheline_aligned_in_smp rq_completed[2];
+
+ struct request_queue *queue;
+ struct blk_mq_ctxs *ctxs;
+ struct kobject kobj;
+} ____cacheline_aligned_in_smp;
+
+void blk_mq_exit_queue(struct request_queue *q);
+int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
+void blk_mq_wake_waiters(struct request_queue *q);
+bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *,
+ unsigned int);
+void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
+ bool kick_requeue_list);
+void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
+struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *start);
+void blk_mq_put_rq_ref(struct request *rq);
+
+/*
+ * Internal helpers for allocating/freeing the request map
+ */
+void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
+ unsigned int hctx_idx);
+void blk_mq_free_rq_map(struct blk_mq_tags *tags, unsigned int flags);
+struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
+ unsigned int hctx_idx,
+ unsigned int nr_tags,
+ unsigned int reserved_tags,
+ unsigned int flags);
+int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
+ unsigned int hctx_idx, unsigned int depth);
+
+/*
+ * Internal helpers for request insertion into sw queues
+ */
+void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
+ bool at_head);
+void blk_mq_request_bypass_insert(struct request *rq, bool at_head,
+ bool run_queue);
+void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
+ struct list_head *list);
+
+/* Used by blk_insert_cloned_request() to issue request directly */
+blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last);
+void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
+ struct list_head *list);
+
+/*
+ * CPU -> queue mappings
+ */
+extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
+
+/*
+ * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
+ * @q: request queue
+ * @type: the hctx type index
+ * @cpu: CPU
+ */
+static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
+ enum hctx_type type,
+ unsigned int cpu)
+{
+ return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]];
+}
+
+/*
+ * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
+ * @q: request queue
+ * @flags: request command flags
+ * @cpu: cpu ctx
+ */
+static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
+ unsigned int flags,
+ struct blk_mq_ctx *ctx)
+{
+ enum hctx_type type = HCTX_TYPE_DEFAULT;
+
+ /*
+ * The caller ensure that if REQ_HIPRI, poll must be enabled.
+ */
+ if (flags & REQ_HIPRI)
+ type = HCTX_TYPE_POLL;
+ else if ((flags & REQ_OP_MASK) == REQ_OP_READ)
+ type = HCTX_TYPE_READ;
+
+ return ctx->hctxs[type];
+}
+
+/*
+ * sysfs helpers
+ */
+extern void blk_mq_sysfs_init(struct request_queue *q);
+extern void blk_mq_sysfs_deinit(struct request_queue *q);
+extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
+extern int blk_mq_sysfs_register(struct request_queue *q);
+extern void blk_mq_sysfs_unregister(struct request_queue *q);
+extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
+
+void blk_mq_release(struct request_queue *q);
+
+static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
+ unsigned int cpu)
+{
+ return per_cpu_ptr(q->queue_ctx, cpu);
+}
+
+/*
+ * This assumes per-cpu software queueing queues. They could be per-node
+ * as well, for instance. For now this is hardcoded as-is. Note that we don't
+ * care about preemption, since we know the ctx's are persistent. This does
+ * mean that we can't rely on ctx always matching the currently running CPU.
+ */
+static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
+{
+ return __blk_mq_get_ctx(q, raw_smp_processor_id());
+}
+
+struct blk_mq_alloc_data {
+ /* input parameter */
+ struct request_queue *q;
+ blk_mq_req_flags_t flags;
+ unsigned int shallow_depth;
+ unsigned int cmd_flags;
+
+ /* input & output parameter */
+ struct blk_mq_ctx *ctx;
+ struct blk_mq_hw_ctx *hctx;
+};
+
+static inline bool blk_mq_is_sbitmap_shared(unsigned int flags)
+{
+ return flags & BLK_MQ_F_TAG_HCTX_SHARED;
+}
+
+static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
+{
+ if (data->q->elevator)
+ return data->hctx->sched_tags;
+
+ return data->hctx->tags;
+}
+
+static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
+{
+ return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
+}
+
+static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
+{
+ return hctx->nr_ctx && hctx->tags;
+}
+
+unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
+void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2]);
+
+static inline void blk_mq_put_dispatch_budget(struct request_queue *q)
+{
+ if (q->mq_ops->put_budget)
+ q->mq_ops->put_budget(q);
+}
+
+static inline bool blk_mq_get_dispatch_budget(struct request_queue *q)
+{
+ if (q->mq_ops->get_budget)
+ return q->mq_ops->get_budget(q);
+ return true;
+}
+
+static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx)
+{
+ if (blk_mq_is_sbitmap_shared(hctx->flags))
+ atomic_inc(&hctx->queue->nr_active_requests_shared_sbitmap);
+ else
+ atomic_inc(&hctx->nr_active);
+}
+
+static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx)
+{
+ if (blk_mq_is_sbitmap_shared(hctx->flags))
+ atomic_dec(&hctx->queue->nr_active_requests_shared_sbitmap);
+ else
+ atomic_dec(&hctx->nr_active);
+}
+
+static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx)
+{
+ if (blk_mq_is_sbitmap_shared(hctx->flags))
+ return atomic_read(&hctx->queue->nr_active_requests_shared_sbitmap);
+ return atomic_read(&hctx->nr_active);
+}
+static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
+ struct request *rq)
+{
+ blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
+ rq->tag = BLK_MQ_NO_TAG;
+
+ if (rq->rq_flags & RQF_MQ_INFLIGHT) {
+ rq->rq_flags &= ~RQF_MQ_INFLIGHT;
+ __blk_mq_dec_active_requests(hctx);
+ }
+}
+
+static inline void blk_mq_put_driver_tag(struct request *rq)
+{
+ if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
+ return;
+
+ __blk_mq_put_driver_tag(rq->mq_hctx, rq);
+}
+
+static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ qmap->mq_map[cpu] = 0;
+}
+
+/*
+ * blk_mq_plug() - Get caller context plug
+ * @q: request queue
+ * @bio : the bio being submitted by the caller context
+ *
+ * Plugging, by design, may delay the insertion of BIOs into the elevator in
+ * order to increase BIO merging opportunities. This however can cause BIO
+ * insertion order to change from the order in which submit_bio() is being
+ * executed in the case of multiple contexts concurrently issuing BIOs to a
+ * device, even if these context are synchronized to tightly control BIO issuing
+ * order. While this is not a problem with regular block devices, this ordering
+ * change can cause write BIO failures with zoned block devices as these
+ * require sequential write patterns to zones. Prevent this from happening by
+ * ignoring the plug state of a BIO issuing context if the target request queue
+ * is for a zoned block device and the BIO to plug is a write operation.
+ *
+ * Return current->plug if the bio can be plugged and NULL otherwise
+ */
+static inline struct blk_plug *blk_mq_plug(struct request_queue *q,
+ struct bio *bio)
+{
+ /*
+ * For regular block devices or read operations, use the context plug
+ * which may be NULL if blk_start_plug() was not executed.
+ */
+ if (!blk_queue_is_zoned(q) || !op_is_write(bio_op(bio)))
+ return current->plug;
+
+ /* Zoned block device write operation case: do not plug the BIO */
+ return NULL;
+}
+
+/*
+ * For shared tag users, we track the number of currently active users
+ * and attempt to provide a fair share of the tag depth for each of them.
+ */
+static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
+ struct sbitmap_queue *bt)
+{
+ unsigned int depth, users;
+
+ if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED))
+ return true;
+
+ /*
+ * Don't try dividing an ant
+ */
+ if (bt->sb.depth == 1)
+ return true;
+
+ if (blk_mq_is_sbitmap_shared(hctx->flags)) {
+ struct request_queue *q = hctx->queue;
+ struct blk_mq_tag_set *set = q->tag_set;
+
+ if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags))
+ return true;
+ users = atomic_read(&set->active_queues_shared_sbitmap);
+ } else {
+ if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
+ return true;
+ users = atomic_read(&hctx->tags->active_queues);
+ }
+
+ if (!users)
+ return true;
+
+ /*
+ * Allow at least some tags
+ */
+ depth = max((bt->sb.depth + users - 1) / users, 4U);
+ return __blk_mq_active_requests(hctx) < depth;
+}
+
+
+#endif