Having another indirect all in the fast path doesn't really help
in our post-spectre world. Also having too many queue type is just
going to create confusion, so I'd rather manage them centrally.
Note that the queue type naming and ordering changes a bit - the
first index now is the default queue for everything not explicitly
marked, the optional ones are read and poll queues.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
block/blk-mq-sysfs.c | 9 +++++-
block/blk-mq.h | 21 +++++++------
drivers/nvme/host/pci.c | 68 +++++++++++++++--------------------------
include/linux/blk-mq.h | 15 ++++-----
4 files changed, 51 insertions(+), 62 deletions(-)
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 6efef1f679f0..9c2df137256a 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -173,9 +173,16 @@ static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
return ret;
}
+static const char *const hctx_types[] = {
+ [HCTX_TYPE_DEFAULT] = "default",
+ [HCTX_TYPE_READ] = "read",
+ [HCTX_TYPE_POLL] = "poll",
+};
+
static ssize_t blk_mq_hw_sysfs_type_show(struct blk_mq_hw_ctx *hctx, char *page)
{
- return sprintf(page, "%u\n", hctx->type);
+ BUILD_BUG_ON(ARRAY_SIZE(hctx_types) != HCTX_MAX_TYPES);
+ return sprintf(page, "%s\n", hctx_types[hctx->type]);
}
static struct attribute *default_ctx_attrs[] = {
diff --git a/block/blk-mq.h b/block/blk-mq.h
index 7291e5379358..a664ea44ffd4 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -81,16 +81,14 @@ 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
- * @hctx_type: the hctx type index
+ * @type: the hctx type index
* @cpu: CPU
*/
static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
- unsigned int hctx_type,
+ enum hctx_type type,
unsigned int cpu)
{
- struct blk_mq_tag_set *set = q->tag_set;
-
- return q->queue_hw_ctx[set->map[hctx_type].mq_map[cpu]];
+ return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]];
}
/*
@@ -103,12 +101,17 @@ static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
unsigned int flags,
unsigned int cpu)
{
- int hctx_type = 0;
+ enum hctx_type type = HCTX_TYPE_DEFAULT;
+
+ if (q->tag_set->nr_maps > HCTX_TYPE_POLL &&
+ ((flags & REQ_HIPRI) && test_bit(QUEUE_FLAG_POLL, &q->queue_flags)))
+ type = HCTX_TYPE_POLL;
- if (q->mq_ops->rq_flags_to_type)
- hctx_type = q->mq_ops->rq_flags_to_type(q, flags);
+ else if (q->tag_set->nr_maps > HCTX_TYPE_READ &&
+ ((flags & REQ_OP_MASK) == REQ_OP_READ))
+ type = HCTX_TYPE_READ;
- return blk_mq_map_queue_type(q, hctx_type, cpu);
+ return blk_mq_map_queue_type(q, type, cpu);
}
/*
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 527907aa6903..a1bb4bb92e7f 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -95,13 +95,6 @@ struct nvme_queue;
static void nvme_dev_disable(struct nvme_dev *dev, bool shutdown);
-enum {
- NVMEQ_TYPE_READ,
- NVMEQ_TYPE_WRITE,
- NVMEQ_TYPE_POLL,
- NVMEQ_TYPE_NR,
-};
-
/*
* Represents an NVM Express device. Each nvme_dev is a PCI function.
*/
@@ -115,7 +108,7 @@ struct nvme_dev {
struct dma_pool *prp_small_pool;
unsigned online_queues;
unsigned max_qid;
- unsigned io_queues[NVMEQ_TYPE_NR];
+ unsigned io_queues[HCTX_MAX_TYPES];
unsigned int num_vecs;
int q_depth;
u32 db_stride;
@@ -499,10 +492,10 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
map->nr_queues = dev->io_queues[i];
if (!map->nr_queues) {
- BUG_ON(i == NVMEQ_TYPE_READ);
+ BUG_ON(i == HCTX_TYPE_DEFAULT);
/* shared set, resuse read set parameters */
- map->nr_queues = dev->io_queues[NVMEQ_TYPE_READ];
+ map->nr_queues = dev->io_queues[HCTX_TYPE_DEFAULT];
qoff = 0;
offset = queue_irq_offset(dev);
}
@@ -512,7 +505,7 @@ static int nvme_pci_map_queues(struct blk_mq_tag_set *set)
* affinity), so use the regular blk-mq cpu mapping
*/
map->queue_offset = qoff;
- if (i != NVMEQ_TYPE_POLL)
+ if (i != HCTX_TYPE_POLL)
blk_mq_pci_map_queues(map, to_pci_dev(dev->dev), offset);
else
blk_mq_map_queues(map);
@@ -961,16 +954,6 @@ static blk_status_t nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
return ret;
}
-static int nvme_rq_flags_to_type(struct request_queue *q, unsigned int flags)
-{
- if ((flags & REQ_HIPRI) && test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
- return NVMEQ_TYPE_POLL;
- if ((flags & REQ_OP_MASK) == REQ_OP_READ)
- return NVMEQ_TYPE_READ;
-
- return NVMEQ_TYPE_WRITE;
-}
-
static void nvme_pci_complete_rq(struct request *req)
{
struct nvme_iod *iod = blk_mq_rq_to_pdu(req);
@@ -1634,7 +1617,6 @@ static const struct blk_mq_ops nvme_mq_admin_ops = {
#define NVME_SHARED_MQ_OPS \
.queue_rq = nvme_queue_rq, \
.commit_rqs = nvme_commit_rqs, \
- .rq_flags_to_type = nvme_rq_flags_to_type, \
.complete = nvme_pci_complete_rq, \
.init_hctx = nvme_init_hctx, \
.init_request = nvme_init_request, \
@@ -1785,9 +1767,9 @@ static int nvme_create_io_queues(struct nvme_dev *dev)
}
max = min(dev->max_qid, dev->ctrl.queue_count - 1);
- if (max != 1 && dev->io_queues[NVMEQ_TYPE_POLL]) {
- rw_queues = dev->io_queues[NVMEQ_TYPE_READ] +
- dev->io_queues[NVMEQ_TYPE_WRITE];
+ if (max != 1 && dev->io_queues[HCTX_TYPE_POLL]) {
+ rw_queues = dev->io_queues[HCTX_TYPE_DEFAULT] +
+ dev->io_queues[HCTX_TYPE_READ];
} else {
rw_queues = max;
}
@@ -2076,9 +2058,9 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues)
* Setup read/write queue split
*/
if (nr_io_queues == 1) {
- dev->io_queues[NVMEQ_TYPE_READ] = 1;
- dev->io_queues[NVMEQ_TYPE_WRITE] = 0;
- dev->io_queues[NVMEQ_TYPE_POLL] = 0;
+ dev->io_queues[HCTX_TYPE_DEFAULT] = 1;
+ dev->io_queues[HCTX_TYPE_READ] = 0;
+ dev->io_queues[HCTX_TYPE_POLL] = 0;
return;
}
@@ -2095,10 +2077,10 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues)
this_p_queues = nr_io_queues - 1;
}
- dev->io_queues[NVMEQ_TYPE_POLL] = this_p_queues;
+ dev->io_queues[HCTX_TYPE_POLL] = this_p_queues;
nr_io_queues -= this_p_queues;
} else
- dev->io_queues[NVMEQ_TYPE_POLL] = 0;
+ dev->io_queues[HCTX_TYPE_POLL] = 0;
/*
* If 'write_queues' is set, ensure it leaves room for at least
@@ -2112,11 +2094,11 @@ static void nvme_calc_io_queues(struct nvme_dev *dev, unsigned int nr_io_queues)
* a queue set.
*/
if (!this_w_queues) {
- dev->io_queues[NVMEQ_TYPE_WRITE] = 0;
- dev->io_queues[NVMEQ_TYPE_READ] = nr_io_queues;
+ dev->io_queues[HCTX_TYPE_DEFAULT] = nr_io_queues;
+ dev->io_queues[HCTX_TYPE_READ] = 0;
} else {
- dev->io_queues[NVMEQ_TYPE_WRITE] = this_w_queues;
- dev->io_queues[NVMEQ_TYPE_READ] = nr_io_queues - this_w_queues;
+ dev->io_queues[HCTX_TYPE_DEFAULT] = this_w_queues;
+ dev->io_queues[HCTX_TYPE_READ] = nr_io_queues - this_w_queues;
}
}
@@ -2138,8 +2120,8 @@ static int nvme_setup_irqs(struct nvme_dev *dev, int nr_io_queues)
*/
do {
nvme_calc_io_queues(dev, nr_io_queues);
- irq_sets[0] = dev->io_queues[NVMEQ_TYPE_READ];
- irq_sets[1] = dev->io_queues[NVMEQ_TYPE_WRITE];
+ irq_sets[0] = dev->io_queues[HCTX_TYPE_DEFAULT];
+ irq_sets[1] = dev->io_queues[HCTX_TYPE_READ];
if (!irq_sets[1])
affd.nr_sets = 1;
@@ -2226,12 +2208,12 @@ static int nvme_setup_io_queues(struct nvme_dev *dev)
dev->num_vecs = result;
result = max(result - 1, 1);
- dev->max_qid = result + dev->io_queues[NVMEQ_TYPE_POLL];
+ dev->max_qid = result + dev->io_queues[HCTX_TYPE_POLL];
- dev_info(dev->ctrl.device, "%d/%d/%d read/write/poll queues\n",
- dev->io_queues[NVMEQ_TYPE_READ],
- dev->io_queues[NVMEQ_TYPE_WRITE],
- dev->io_queues[NVMEQ_TYPE_POLL]);
+ dev_info(dev->ctrl.device, "%d/%d/%d default/read/poll queues\n",
+ dev->io_queues[HCTX_TYPE_DEFAULT],
+ dev->io_queues[HCTX_TYPE_READ],
+ dev->io_queues[HCTX_TYPE_POLL]);
/*
* Should investigate if there's a performance win from allocating
@@ -2332,13 +2314,13 @@ static int nvme_dev_add(struct nvme_dev *dev)
int ret;
if (!dev->ctrl.tagset) {
- if (!dev->io_queues[NVMEQ_TYPE_POLL])
+ if (!dev->io_queues[HCTX_TYPE_POLL])
dev->tagset.ops = &nvme_mq_ops;
else
dev->tagset.ops = &nvme_mq_poll_noirq_ops;
dev->tagset.nr_hw_queues = dev->online_queues - 1;
- dev->tagset.nr_maps = NVMEQ_TYPE_NR;
+ dev->tagset.nr_maps = HCTX_MAX_TYPES;
dev->tagset.timeout = NVME_IO_TIMEOUT;
dev->tagset.numa_node = dev_to_node(dev->dev);
dev->tagset.queue_depth =
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 467f1dd21ccf..57eda7b20243 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -81,8 +81,12 @@ struct blk_mq_queue_map {
unsigned int queue_offset;
};
-enum {
- HCTX_MAX_TYPES = 3,
+enum hctx_type {
+ HCTX_TYPE_DEFAULT, /* all I/O not otherwise accounted for */
+ HCTX_TYPE_READ, /* just for READ I/O */
+ HCTX_TYPE_POLL, /* polled I/O of any kind */
+
+ HCTX_MAX_TYPES,
};
struct blk_mq_tag_set {
@@ -118,8 +122,6 @@ struct blk_mq_queue_data {
typedef blk_status_t (queue_rq_fn)(struct blk_mq_hw_ctx *,
const struct blk_mq_queue_data *);
typedef void (commit_rqs_fn)(struct blk_mq_hw_ctx *);
-/* takes rq->cmd_flags as input, returns a hardware type index */
-typedef int (rq_flags_to_type_fn)(struct request_queue *, unsigned int);
typedef bool (get_budget_fn)(struct blk_mq_hw_ctx *);
typedef void (put_budget_fn)(struct blk_mq_hw_ctx *);
typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool);
@@ -154,11 +156,6 @@ struct blk_mq_ops {
*/
commit_rqs_fn *commit_rqs;
- /*
- * Return a queue map type for the given request/bio flags
- */
- rq_flags_to_type_fn *rq_flags_to_type;
-
/*
* Reserve budget before queue request, once .queue_rq is
* run, it is driver's responsibility to release the
--
2.19.1
