#include "blk-mq-sched.h"
#include "blk-rq-qos.h"
-static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie);
static void blk_mq_poll_stats_start(struct request_queue *q);
static void blk_mq_poll_stats_fn(struct blk_stat_callback *cb);
static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx)
{
- if (!sbitmap_test_bit(&hctx->ctx_map, ctx->index_hw))
- sbitmap_set_bit(&hctx->ctx_map, ctx->index_hw);
+ const int bit = ctx->index_hw[hctx->type];
+
+ if (!sbitmap_test_bit(&hctx->ctx_map, bit))
+ sbitmap_set_bit(&hctx->ctx_map, bit);
}
static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx)
{
- sbitmap_clear_bit(&hctx->ctx_map, ctx->index_hw);
+ const int bit = ctx->index_hw[hctx->type];
+
+ sbitmap_clear_bit(&hctx->ctx_map, bit);
}
struct mq_inflight {
unsigned int *inflight;
};
-static void blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
+static bool blk_mq_check_inflight(struct blk_mq_hw_ctx *hctx,
struct request *rq, void *priv,
bool reserved)
{
struct mq_inflight *mi = priv;
/*
- * index[0] counts the specific partition that was asked for. index[1]
- * counts the ones that are active on the whole device, so increment
- * that if mi->part is indeed a partition, and not a whole device.
+ * index[0] counts the specific partition that was asked for.
*/
if (rq->part == mi->part)
mi->inflight[0]++;
- if (mi->part->partno)
- mi->inflight[1]++;
+
+ return true;
}
-void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
- unsigned int inflight[2])
+unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
{
+ unsigned inflight[2];
struct mq_inflight mi = { .part = part, .inflight = inflight, };
inflight[0] = inflight[1] = 0;
blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi);
+
+ return inflight[0];
}
-static void blk_mq_check_inflight_rw(struct blk_mq_hw_ctx *hctx,
+static bool blk_mq_check_inflight_rw(struct blk_mq_hw_ctx *hctx,
struct request *rq, void *priv,
bool reserved)
{
if (rq->part == mi->part)
mi->inflight[rq_data_dir(rq)]++;
+
+ return true;
}
void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
freeze_depth = atomic_inc_return(&q->mq_freeze_depth);
if (freeze_depth == 1) {
percpu_ref_kill(&q->q_usage_counter);
- if (q->mq_ops)
+ if (queue_is_mq(q))
blk_mq_run_hw_queues(q, false);
}
}
* exported to drivers as the only user for unfreeze is blk_mq.
*/
blk_freeze_queue_start(q);
- if (!q->mq_ops)
- blk_drain_queue(q);
blk_mq_freeze_queue_wait(q);
}
}
EXPORT_SYMBOL(blk_mq_can_queue);
+/*
+ * Only need start/end time stamping if we have stats enabled, or using
+ * an IO scheduler.
+ */
+static inline bool blk_mq_need_time_stamp(struct request *rq)
+{
+ return (rq->rq_flags & RQF_IO_STAT) || rq->q->elevator;
+}
+
static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data,
unsigned int tag, unsigned int op)
{
/* csd/requeue_work/fifo_time is initialized before use */
rq->q = data->q;
rq->mq_ctx = data->ctx;
+ rq->mq_hctx = data->hctx;
rq->rq_flags = rq_flags;
- rq->cpu = -1;
rq->cmd_flags = op;
if (data->flags & BLK_MQ_REQ_PREEMPT)
rq->rq_flags |= RQF_PREEMPT;
RB_CLEAR_NODE(&rq->rb_node);
rq->rq_disk = NULL;
rq->part = NULL;
- rq->start_time_ns = ktime_get_ns();
+ if (blk_mq_need_time_stamp(rq))
+ rq->start_time_ns = ktime_get_ns();
+ else
+ rq->start_time_ns = 0;
rq->io_start_time_ns = 0;
rq->nr_phys_segments = 0;
#if defined(CONFIG_BLK_DEV_INTEGRITY)
rq->special = NULL;
/* tag was already set */
rq->extra_len = 0;
- rq->__deadline = 0;
+ WRITE_ONCE(rq->deadline, 0);
- INIT_LIST_HEAD(&rq->timeout_list);
rq->timeout = 0;
rq->end_io = NULL;
rq->end_io_data = NULL;
rq->next_rq = NULL;
-#ifdef CONFIG_BLK_CGROUP
- rq->rl = NULL;
-#endif
-
data->ctx->rq_dispatched[op_is_sync(op)]++;
refcount_set(&rq->ref, 1);
return rq;
}
static struct request *blk_mq_get_request(struct request_queue *q,
- struct bio *bio, unsigned int op,
- struct blk_mq_alloc_data *data)
+ struct bio *bio,
+ struct blk_mq_alloc_data *data)
{
struct elevator_queue *e = q->elevator;
struct request *rq;
put_ctx_on_error = true;
}
if (likely(!data->hctx))
- data->hctx = blk_mq_map_queue(q, data->ctx->cpu);
- if (op & REQ_NOWAIT)
+ data->hctx = blk_mq_map_queue(q, data->cmd_flags,
+ data->ctx->cpu);
+ if (data->cmd_flags & REQ_NOWAIT)
data->flags |= BLK_MQ_REQ_NOWAIT;
if (e) {
* dispatch list. Don't include reserved tags in the
* limiting, as it isn't useful.
*/
- if (!op_is_flush(op) && e->type->ops.mq.limit_depth &&
+ if (!op_is_flush(data->cmd_flags) &&
+ e->type->ops.limit_depth &&
!(data->flags & BLK_MQ_REQ_RESERVED))
- e->type->ops.mq.limit_depth(op, data);
+ e->type->ops.limit_depth(data->cmd_flags, data);
} else {
blk_mq_tag_busy(data->hctx);
}
return NULL;
}
- rq = blk_mq_rq_ctx_init(data, tag, op);
- if (!op_is_flush(op)) {
+ rq = blk_mq_rq_ctx_init(data, tag, data->cmd_flags);
+ if (!op_is_flush(data->cmd_flags)) {
rq->elv.icq = NULL;
- if (e && e->type->ops.mq.prepare_request) {
- if (e->type->icq_cache && rq_ioc(bio))
- blk_mq_sched_assign_ioc(rq, bio);
+ if (e && e->type->ops.prepare_request) {
+ if (e->type->icq_cache)
+ blk_mq_sched_assign_ioc(rq);
- e->type->ops.mq.prepare_request(rq, bio);
+ e->type->ops.prepare_request(rq, bio);
rq->rq_flags |= RQF_ELVPRIV;
}
}
struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op,
blk_mq_req_flags_t flags)
{
- struct blk_mq_alloc_data alloc_data = { .flags = flags };
+ struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op };
struct request *rq;
int ret;
if (ret)
return ERR_PTR(ret);
- rq = blk_mq_get_request(q, NULL, op, &alloc_data);
+ rq = blk_mq_get_request(q, NULL, &alloc_data);
blk_queue_exit(q);
if (!rq)
struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
unsigned int op, blk_mq_req_flags_t flags, unsigned int hctx_idx)
{
- struct blk_mq_alloc_data alloc_data = { .flags = flags };
+ struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op };
struct request *rq;
unsigned int cpu;
int ret;
cpu = cpumask_first_and(alloc_data.hctx->cpumask, cpu_online_mask);
alloc_data.ctx = __blk_mq_get_ctx(q, cpu);
- rq = blk_mq_get_request(q, NULL, op, &alloc_data);
+ rq = blk_mq_get_request(q, NULL, &alloc_data);
blk_queue_exit(q);
if (!rq)
{
struct request_queue *q = rq->q;
struct blk_mq_ctx *ctx = rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
+ struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
const int sched_tag = rq->internal_tag;
blk_pm_mark_last_busy(rq);
+ rq->mq_hctx = NULL;
if (rq->tag != -1)
blk_mq_put_tag(hctx, hctx->tags, ctx, rq->tag);
if (sched_tag != -1)
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
struct blk_mq_ctx *ctx = rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
+ struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
if (rq->rq_flags & RQF_ELVPRIV) {
- if (e && e->type->ops.mq.finish_request)
- e->type->ops.mq.finish_request(rq);
+ if (e && e->type->ops.finish_request)
+ e->type->ops.finish_request(rq);
if (rq->elv.icq) {
put_io_context(rq->elv.icq->ioc);
rq->elv.icq = NULL;
rq_qos_done(q, rq);
- if (blk_rq_rl(rq))
- blk_put_rl(blk_rq_rl(rq));
-
WRITE_ONCE(rq->state, MQ_RQ_IDLE);
if (refcount_dec_and_test(&rq->ref))
__blk_mq_free_request(rq);
inline void __blk_mq_end_request(struct request *rq, blk_status_t error)
{
- u64 now = ktime_get_ns();
+ u64 now = 0;
+
+ if (blk_mq_need_time_stamp(rq))
+ now = ktime_get_ns();
if (rq->rq_flags & RQF_STATS) {
blk_mq_poll_stats_start(rq->q);
static void __blk_mq_complete_request_remote(void *data)
{
struct request *rq = data;
+ struct request_queue *q = rq->q;
- rq->q->softirq_done_fn(rq);
+ q->mq_ops->complete(rq);
}
static void __blk_mq_complete_request(struct request *rq)
{
struct blk_mq_ctx *ctx = rq->mq_ctx;
+ struct request_queue *q = rq->q;
bool shared = false;
int cpu;
- if (!blk_mq_mark_complete(rq))
- return;
-
+ WRITE_ONCE(rq->state, MQ_RQ_COMPLETE);
/*
* Most of single queue controllers, there is only one irq vector
* for handling IO completion, and the only irq's affinity is set
* So complete IO reqeust in softirq context in case of single queue
* for not degrading IO performance by irqsoff latency.
*/
- if (rq->q->nr_hw_queues == 1) {
+ if (q->nr_hw_queues == 1) {
__blk_complete_request(rq);
return;
}
- if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) {
- rq->q->softirq_done_fn(rq);
+ /*
+ * For a polled request, always complete locallly, it's pointless
+ * to redirect the completion.
+ */
+ if ((rq->cmd_flags & REQ_HIPRI) ||
+ !test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags)) {
+ q->mq_ops->complete(rq);
return;
}
cpu = get_cpu();
- if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags))
+ if (!test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags))
shared = cpus_share_cache(cpu, ctx->cpu);
if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) {
rq->csd.flags = 0;
smp_call_function_single_async(ctx->cpu, &rq->csd);
} else {
- rq->q->softirq_done_fn(rq);
+ q->mq_ops->complete(rq);
}
put_cpu();
}
* Ends all I/O on a request. It does not handle partial completions.
* The actual completion happens out-of-order, through a IPI handler.
**/
-void blk_mq_complete_request(struct request *rq)
+bool blk_mq_complete_request(struct request *rq)
{
if (unlikely(blk_should_fake_timeout(rq->q)))
- return;
+ return false;
__blk_mq_complete_request(rq);
+ return true;
}
EXPORT_SYMBOL(blk_mq_complete_request);
/* this request will be re-inserted to io scheduler queue */
blk_mq_sched_requeue_request(rq);
- BUG_ON(blk_queued_rq(rq));
+ BUG_ON(!list_empty(&rq->queuelist));
blk_mq_add_to_requeue_list(rq, true, kick_requeue_list);
}
EXPORT_SYMBOL(blk_mq_requeue_request);
}
EXPORT_SYMBOL(blk_mq_tag_to_rq);
+static bool blk_mq_rq_inflight(struct blk_mq_hw_ctx *hctx, struct request *rq,
+ void *priv, bool reserved)
+{
+ /*
+ * If we find a request that is inflight and the queue matches,
+ * we know the queue is busy. Return false to stop the iteration.
+ */
+ if (rq->state == MQ_RQ_IN_FLIGHT && rq->q == hctx->queue) {
+ bool *busy = priv;
+
+ *busy = true;
+ return false;
+ }
+
+ return true;
+}
+
+bool blk_mq_queue_inflight(struct request_queue *q)
+{
+ bool busy = false;
+
+ blk_mq_queue_tag_busy_iter(q, blk_mq_rq_inflight, &busy);
+ return busy;
+}
+EXPORT_SYMBOL_GPL(blk_mq_queue_inflight);
+
static void blk_mq_rq_timed_out(struct request *req, bool reserved)
{
req->rq_flags |= RQF_TIMED_OUT;
if (rq->rq_flags & RQF_TIMED_OUT)
return false;
- deadline = blk_rq_deadline(rq);
+ deadline = READ_ONCE(rq->deadline);
if (time_after_eq(jiffies, deadline))
return true;
return false;
}
-static void blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
+static bool blk_mq_check_expired(struct blk_mq_hw_ctx *hctx,
struct request *rq, void *priv, bool reserved)
{
unsigned long *next = priv;
* so we're not unnecessarilly synchronizing across CPUs.
*/
if (!blk_mq_req_expired(rq, next))
- return;
+ return true;
/*
* We have reason to believe the request may be expired. Take a
* timeout handler to posting a natural completion.
*/
if (!refcount_inc_not_zero(&rq->ref))
- return;
+ return true;
/*
* The request is now locked and cannot be reallocated underneath the
blk_mq_rq_timed_out(rq, reserved);
if (refcount_dec_and_test(&rq->ref))
__blk_mq_free_request(rq);
+
+ return true;
}
static void blk_mq_timeout_work(struct work_struct *work)
struct flush_busy_ctx_data *flush_data = data;
struct blk_mq_hw_ctx *hctx = flush_data->hctx;
struct blk_mq_ctx *ctx = hctx->ctxs[bitnr];
+ enum hctx_type type = hctx->type;
spin_lock(&ctx->lock);
- list_splice_tail_init(&ctx->rq_list, flush_data->list);
+ list_splice_tail_init(&ctx->rq_lists[type], flush_data->list);
sbitmap_clear_bit(sb, bitnr);
spin_unlock(&ctx->lock);
return true;
struct dispatch_rq_data *dispatch_data = data;
struct blk_mq_hw_ctx *hctx = dispatch_data->hctx;
struct blk_mq_ctx *ctx = hctx->ctxs[bitnr];
+ enum hctx_type type = hctx->type;
spin_lock(&ctx->lock);
- if (!list_empty(&ctx->rq_list)) {
- dispatch_data->rq = list_entry_rq(ctx->rq_list.next);
+ if (!list_empty(&ctx->rq_lists[type])) {
+ dispatch_data->rq = list_entry_rq(ctx->rq_lists[type].next);
list_del_init(&dispatch_data->rq->queuelist);
- if (list_empty(&ctx->rq_list))
+ if (list_empty(&ctx->rq_lists[type]))
sbitmap_clear_bit(sb, bitnr);
}
spin_unlock(&ctx->lock);
struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *start)
{
- unsigned off = start ? start->index_hw : 0;
+ unsigned off = start ? start->index_hw[hctx->type] : 0;
struct dispatch_rq_data data = {
.hctx = hctx,
.rq = NULL,
{
struct blk_mq_alloc_data data = {
.q = rq->q,
- .hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu),
+ .hctx = rq->mq_hctx,
.flags = BLK_MQ_REQ_NOWAIT,
+ .cmd_flags = rq->cmd_flags,
};
bool shared;
rq = list_first_entry(list, struct request, queuelist);
- hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
+ hctx = rq->mq_hctx;
if (!got_budget && !blk_mq_get_dispatch_budget(hctx))
break;
if (!list_empty(list)) {
bool needs_restart;
+ /*
+ * If we didn't flush the entire list, we could have told
+ * the driver there was more coming, but that turned out to
+ * be a lie.
+ */
+ if (q->mq_ops->commit_rqs)
+ q->mq_ops->commit_rqs(hctx);
+
spin_lock(&hctx->lock);
list_splice_init(list, &hctx->dispatch);
spin_unlock(&hctx->lock);
bool at_head)
{
struct blk_mq_ctx *ctx = rq->mq_ctx;
+ enum hctx_type type = hctx->type;
lockdep_assert_held(&ctx->lock);
trace_block_rq_insert(hctx->queue, rq);
if (at_head)
- list_add(&rq->queuelist, &ctx->rq_list);
+ list_add(&rq->queuelist, &ctx->rq_lists[type]);
else
- list_add_tail(&rq->queuelist, &ctx->rq_list);
+ list_add_tail(&rq->queuelist, &ctx->rq_lists[type]);
}
void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
*/
void blk_mq_request_bypass_insert(struct request *rq, bool run_queue)
{
- struct blk_mq_ctx *ctx = rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(rq->q, ctx->cpu);
+ struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
spin_lock(&hctx->lock);
list_add_tail(&rq->queuelist, &hctx->dispatch);
{
struct request *rq;
+ enum hctx_type type = hctx->type;
/*
* preemption doesn't flush plug list, so it's possible ctx->cpu is
}
spin_lock(&ctx->lock);
- list_splice_tail_init(list, &ctx->rq_list);
+ list_splice_tail_init(list, &ctx->rq_lists[type]);
blk_mq_hctx_mark_pending(hctx, ctx);
spin_unlock(&ctx->lock);
}
-static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b)
{
struct request *rqa = container_of(a, struct request, queuelist);
struct request *rqb = container_of(b, struct request, queuelist);
- return !(rqa->mq_ctx < rqb->mq_ctx ||
- (rqa->mq_ctx == rqb->mq_ctx &&
- blk_rq_pos(rqa) < blk_rq_pos(rqb)));
+ if (rqa->mq_ctx < rqb->mq_ctx)
+ return -1;
+ else if (rqa->mq_ctx > rqb->mq_ctx)
+ return 1;
+ else if (rqa->mq_hctx < rqb->mq_hctx)
+ return -1;
+ else if (rqa->mq_hctx > rqb->mq_hctx)
+ return 1;
+
+ return blk_rq_pos(rqa) > blk_rq_pos(rqb);
}
void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
{
+ struct blk_mq_hw_ctx *this_hctx;
struct blk_mq_ctx *this_ctx;
struct request_queue *this_q;
struct request *rq;
LIST_HEAD(list);
- LIST_HEAD(ctx_list);
+ LIST_HEAD(rq_list);
unsigned int depth;
list_splice_init(&plug->mq_list, &list);
+ plug->rq_count = 0;
- list_sort(NULL, &list, plug_ctx_cmp);
+ if (plug->rq_count > 2 && plug->multiple_queues)
+ list_sort(NULL, &list, plug_rq_cmp);
this_q = NULL;
+ this_hctx = NULL;
this_ctx = NULL;
depth = 0;
rq = list_entry_rq(list.next);
list_del_init(&rq->queuelist);
BUG_ON(!rq->q);
- if (rq->mq_ctx != this_ctx) {
- if (this_ctx) {
+ if (rq->mq_hctx != this_hctx || rq->mq_ctx != this_ctx) {
+ if (this_hctx) {
trace_block_unplug(this_q, depth, !from_schedule);
- blk_mq_sched_insert_requests(this_q, this_ctx,
- &ctx_list,
+ blk_mq_sched_insert_requests(this_hctx, this_ctx,
+ &rq_list,
from_schedule);
}
- this_ctx = rq->mq_ctx;
this_q = rq->q;
+ this_ctx = rq->mq_ctx;
+ this_hctx = rq->mq_hctx;
depth = 0;
}
depth++;
- list_add_tail(&rq->queuelist, &ctx_list);
+ list_add_tail(&rq->queuelist, &rq_list);
}
/*
- * If 'this_ctx' is set, we know we have entries to complete
- * on 'ctx_list'. Do those.
+ * If 'this_hctx' is set, we know we have entries to complete
+ * on 'rq_list'. Do those.
*/
- if (this_ctx) {
+ if (this_hctx) {
trace_block_unplug(this_q, depth, !from_schedule);
- blk_mq_sched_insert_requests(this_q, this_ctx, &ctx_list,
+ blk_mq_sched_insert_requests(this_hctx, this_ctx, &rq_list,
from_schedule);
}
}
{
blk_init_request_from_bio(rq, bio);
- blk_rq_set_rl(rq, blk_get_rl(rq->q, bio));
-
blk_account_io_start(rq, true);
}
-static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq)
-{
- if (rq->tag != -1)
- return blk_tag_to_qc_t(rq->tag, hctx->queue_num, false);
-
- return blk_tag_to_qc_t(rq->internal_tag, hctx->queue_num, true);
-}
-
static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx,
struct request *rq,
- blk_qc_t *cookie)
+ blk_qc_t *cookie, bool last)
{
struct request_queue *q = rq->q;
struct blk_mq_queue_data bd = {
.rq = rq,
- .last = true,
+ .last = last,
};
blk_qc_t new_cookie;
blk_status_t ret;
return ret;
}
-static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
+blk_status_t blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
struct request *rq,
blk_qc_t *cookie,
- bool bypass_insert)
+ bool bypass, bool last)
{
struct request_queue *q = rq->q;
bool run_queue = true;
+ blk_status_t ret = BLK_STS_RESOURCE;
+ int srcu_idx;
+ bool force = false;
+ hctx_lock(hctx, &srcu_idx);
/*
- * RCU or SRCU read lock is needed before checking quiesced flag.
+ * hctx_lock is needed before checking quiesced flag.
*
- * When queue is stopped or quiesced, ignore 'bypass_insert' from
- * blk_mq_request_issue_directly(), and return BLK_STS_OK to caller,
- * and avoid driver to try to dispatch again.
+ * When queue is stopped or quiesced, ignore 'bypass', insert
+ * and return BLK_STS_OK to caller, and avoid driver to try to
+ * dispatch again.
*/
- if (blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q)) {
+ if (unlikely(blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q))) {
run_queue = false;
- bypass_insert = false;
- goto insert;
+ bypass = false;
+ goto out_unlock;
}
- if (q->elevator && !bypass_insert)
- goto insert;
+ if (unlikely(q->elevator && !bypass))
+ goto out_unlock;
if (!blk_mq_get_dispatch_budget(hctx))
- goto insert;
+ goto out_unlock;
if (!blk_mq_get_driver_tag(rq)) {
blk_mq_put_dispatch_budget(hctx);
- goto insert;
+ goto out_unlock;
}
- return __blk_mq_issue_directly(hctx, rq, cookie);
-insert:
- if (bypass_insert)
- return BLK_STS_RESOURCE;
-
- blk_mq_sched_insert_request(rq, false, run_queue, false);
- return BLK_STS_OK;
-}
-
-static void blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
- struct request *rq, blk_qc_t *cookie)
-{
- blk_status_t ret;
- int srcu_idx;
-
- might_sleep_if(hctx->flags & BLK_MQ_F_BLOCKING);
-
- hctx_lock(hctx, &srcu_idx);
-
- ret = __blk_mq_try_issue_directly(hctx, rq, cookie, false);
- if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE)
- blk_mq_sched_insert_request(rq, false, true, false);
- else if (ret != BLK_STS_OK)
- blk_mq_end_request(rq, ret);
-
- hctx_unlock(hctx, srcu_idx);
-}
-
-blk_status_t blk_mq_request_issue_directly(struct request *rq)
-{
- blk_status_t ret;
- int srcu_idx;
- blk_qc_t unused_cookie;
- struct blk_mq_ctx *ctx = rq->mq_ctx;
- struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(rq->q, ctx->cpu);
-
- hctx_lock(hctx, &srcu_idx);
- ret = __blk_mq_try_issue_directly(hctx, rq, &unused_cookie, true);
+ /*
+ * Always add a request that has been through
+ *.queue_rq() to the hardware dispatch list.
+ */
+ force = true;
+ ret = __blk_mq_issue_directly(hctx, rq, cookie, last);
+out_unlock:
hctx_unlock(hctx, srcu_idx);
+ switch (ret) {
+ case BLK_STS_OK:
+ break;
+ case BLK_STS_DEV_RESOURCE:
+ case BLK_STS_RESOURCE:
+ if (force) {
+ blk_mq_request_bypass_insert(rq, run_queue);
+ /*
+ * We have to return BLK_STS_OK for the DM
+ * to avoid livelock. Otherwise, we return
+ * the real result to indicate whether the
+ * request is direct-issued successfully.
+ */
+ ret = bypass ? BLK_STS_OK : ret;
+ } else if (!bypass) {
+ blk_mq_sched_insert_request(rq, false,
+ run_queue, false);
+ }
+ break;
+ default:
+ if (!bypass)
+ blk_mq_end_request(rq, ret);
+ break;
+ }
return ret;
}
void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
struct list_head *list)
{
+ blk_qc_t unused;
+ blk_status_t ret = BLK_STS_OK;
+
while (!list_empty(list)) {
- blk_status_t ret;
struct request *rq = list_first_entry(list, struct request,
queuelist);
list_del_init(&rq->queuelist);
- ret = blk_mq_request_issue_directly(rq);
- if (ret != BLK_STS_OK) {
- if (ret == BLK_STS_RESOURCE ||
- ret == BLK_STS_DEV_RESOURCE) {
- list_add(&rq->queuelist, list);
- break;
- }
- blk_mq_end_request(rq, ret);
- }
+ if (ret == BLK_STS_OK)
+ ret = blk_mq_try_issue_directly(hctx, rq, &unused,
+ false,
+ list_empty(list));
+ else
+ blk_mq_sched_insert_request(rq, false, true, false);
+ }
+
+ /*
+ * If we didn't flush the entire list, we could have told
+ * the driver there was more coming, but that turned out to
+ * be a lie.
+ */
+ if (ret != BLK_STS_OK && hctx->queue->mq_ops->commit_rqs)
+ hctx->queue->mq_ops->commit_rqs(hctx);
+}
+
+static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq)
+{
+ list_add_tail(&rq->queuelist, &plug->mq_list);
+ plug->rq_count++;
+ if (!plug->multiple_queues && !list_is_singular(&plug->mq_list)) {
+ struct request *tmp;
+
+ tmp = list_first_entry(&plug->mq_list, struct request,
+ queuelist);
+ if (tmp->q != rq->q)
+ plug->multiple_queues = true;
}
}
{
const int is_sync = op_is_sync(bio->bi_opf);
const int is_flush_fua = op_is_flush(bio->bi_opf);
- struct blk_mq_alloc_data data = { .flags = 0 };
+ struct blk_mq_alloc_data data = { .flags = 0, .cmd_flags = bio->bi_opf };
struct request *rq;
- unsigned int request_count = 0;
struct blk_plug *plug;
struct request *same_queue_rq = NULL;
blk_qc_t cookie;
return BLK_QC_T_NONE;
if (!is_flush_fua && !blk_queue_nomerges(q) &&
- blk_attempt_plug_merge(q, bio, &request_count, &same_queue_rq))
+ blk_attempt_plug_merge(q, bio, &same_queue_rq))
return BLK_QC_T_NONE;
if (blk_mq_sched_bio_merge(q, bio))
return BLK_QC_T_NONE;
- rq_qos_throttle(q, bio, NULL);
+ rq_qos_throttle(q, bio);
- rq = blk_mq_get_request(q, bio, bio->bi_opf, &data);
+ rq = blk_mq_get_request(q, bio, &data);
if (unlikely(!rq)) {
rq_qos_cleanup(q, bio);
if (bio->bi_opf & REQ_NOWAIT)
/* bypass scheduler for flush rq */
blk_insert_flush(rq);
blk_mq_run_hw_queue(data.hctx, true);
- } else if (plug && q->nr_hw_queues == 1) {
+ } else if (plug && (q->nr_hw_queues == 1 || q->mq_ops->commit_rqs)) {
+ /*
+ * Use plugging if we have a ->commit_rqs() hook as well, as
+ * we know the driver uses bd->last in a smart fashion.
+ */
+ unsigned int request_count = plug->rq_count;
struct request *last = NULL;
blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio);
- /*
- * @request_count may become stale because of schedule
- * out, so check the list again.
- */
- if (list_empty(&plug->mq_list))
- request_count = 0;
- else if (blk_queue_nomerges(q))
- request_count = blk_plug_queued_count(q);
-
if (!request_count)
trace_block_plug(q);
else
trace_block_plug(q);
}
- list_add_tail(&rq->queuelist, &plug->mq_list);
+ blk_add_rq_to_plug(plug, rq);
} else if (plug && !blk_queue_nomerges(q)) {
blk_mq_bio_to_request(rq, bio);
*/
if (list_empty(&plug->mq_list))
same_queue_rq = NULL;
- if (same_queue_rq)
+ if (same_queue_rq) {
list_del_init(&same_queue_rq->queuelist);
- list_add_tail(&rq->queuelist, &plug->mq_list);
+ plug->rq_count--;
+ }
+ blk_add_rq_to_plug(plug, rq);
blk_mq_put_ctx(data.ctx);
if (same_queue_rq) {
- data.hctx = blk_mq_map_queue(q,
- same_queue_rq->mq_ctx->cpu);
+ data.hctx = same_queue_rq->mq_hctx;
blk_mq_try_issue_directly(data.hctx, same_queue_rq,
- &cookie);
+ &cookie, false, 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);
+ blk_mq_try_issue_directly(data.hctx, rq, &cookie, false, true);
} else {
blk_mq_put_ctx(data.ctx);
blk_mq_bio_to_request(rq, bio);
struct blk_mq_tags *tags;
int node;
- node = blk_mq_hw_queue_to_node(set->mq_map, hctx_idx);
+ node = blk_mq_hw_queue_to_node(&set->map[0], hctx_idx);
if (node == NUMA_NO_NODE)
node = set->numa_node;
size_t rq_size, left;
int node;
- node = blk_mq_hw_queue_to_node(set->mq_map, hctx_idx);
+ node = blk_mq_hw_queue_to_node(&set->map[0], hctx_idx);
if (node == NUMA_NO_NODE)
node = set->numa_node;
struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
LIST_HEAD(tmp);
+ enum hctx_type type;
hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead);
ctx = __blk_mq_get_ctx(hctx->queue, cpu);
+ type = hctx->type;
spin_lock(&ctx->lock);
- if (!list_empty(&ctx->rq_list)) {
- list_splice_init(&ctx->rq_list, &tmp);
+ if (!list_empty(&ctx->rq_lists[type])) {
+ list_splice_init(&ctx->rq_lists[type], &tmp);
blk_mq_hctx_clear_pending(hctx, ctx);
}
spin_unlock(&ctx->lock);
static void blk_mq_init_cpu_queues(struct request_queue *q,
unsigned int nr_hw_queues)
{
- unsigned int i;
+ struct blk_mq_tag_set *set = q->tag_set;
+ unsigned int i, j;
for_each_possible_cpu(i) {
struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i);
struct blk_mq_hw_ctx *hctx;
+ int k;
__ctx->cpu = i;
spin_lock_init(&__ctx->lock);
- INIT_LIST_HEAD(&__ctx->rq_list);
+ for (k = HCTX_TYPE_DEFAULT; k < HCTX_MAX_TYPES; k++)
+ INIT_LIST_HEAD(&__ctx->rq_lists[k]);
+
__ctx->queue = q;
/*
* Set local node, IFF we have more than one hw queue. If
* not, we remain on the home node of the device
*/
- hctx = blk_mq_map_queue(q, i);
- if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE)
- hctx->numa_node = local_memory_node(cpu_to_node(i));
+ for (j = 0; j < set->nr_maps; j++) {
+ hctx = blk_mq_map_queue_type(q, j, i);
+ if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE)
+ hctx->numa_node = local_memory_node(cpu_to_node(i));
+ }
}
}
static void blk_mq_free_map_and_requests(struct blk_mq_tag_set *set,
unsigned int hctx_idx)
{
- if (set->tags[hctx_idx]) {
+ if (set->tags && set->tags[hctx_idx]) {
blk_mq_free_rqs(set, set->tags[hctx_idx], hctx_idx);
blk_mq_free_rq_map(set->tags[hctx_idx]);
set->tags[hctx_idx] = NULL;
static void blk_mq_map_swqueue(struct request_queue *q)
{
- unsigned int i, hctx_idx;
+ unsigned int i, j, hctx_idx;
struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
struct blk_mq_tag_set *set = q->tag_set;
* If the cpu isn't present, the cpu is mapped to first hctx.
*/
for_each_possible_cpu(i) {
- hctx_idx = q->mq_map[i];
+ hctx_idx = set->map[0].mq_map[i];
/* unmapped hw queue can be remapped after CPU topo changed */
if (!set->tags[hctx_idx] &&
!__blk_mq_alloc_rq_map(set, hctx_idx)) {
* case, remap the current ctx to hctx[0] which
* is guaranteed to always have tags allocated
*/
- q->mq_map[i] = 0;
+ set->map[0].mq_map[i] = 0;
}
ctx = per_cpu_ptr(q->queue_ctx, i);
- hctx = blk_mq_map_queue(q, i);
+ for (j = 0; j < set->nr_maps; j++) {
+ if (!set->map[j].nr_queues)
+ continue;
+
+ hctx = blk_mq_map_queue_type(q, j, i);
+
+ /*
+ * If the CPU is already set in the mask, then we've
+ * mapped this one already. This can happen if
+ * devices share queues across queue maps.
+ */
+ if (cpumask_test_cpu(i, hctx->cpumask))
+ continue;
+
+ cpumask_set_cpu(i, hctx->cpumask);
+ hctx->type = j;
+ ctx->index_hw[hctx->type] = hctx->nr_ctx;
+ hctx->ctxs[hctx->nr_ctx++] = ctx;
- cpumask_set_cpu(i, hctx->cpumask);
- ctx->index_hw = hctx->nr_ctx;
- hctx->ctxs[hctx->nr_ctx++] = ctx;
+ /*
+ * If the nr_ctx type overflows, we have exceeded the
+ * amount of sw queues we can support.
+ */
+ BUG_ON(!hctx->nr_ctx);
+ }
}
mutex_unlock(&q->sysfs_lock);
static void blk_mq_add_queue_tag_set(struct blk_mq_tag_set *set,
struct request_queue *q)
{
- q->tag_set = set;
-
mutex_lock(&set->tag_list_lock);
/*
mutex_unlock(&set->tag_list_lock);
}
+/* All allocations will be freed in release handler of q->mq_kobj */
+static int blk_mq_alloc_ctxs(struct request_queue *q)
+{
+ struct blk_mq_ctxs *ctxs;
+ int cpu;
+
+ ctxs = kzalloc(sizeof(*ctxs), GFP_KERNEL);
+ if (!ctxs)
+ return -ENOMEM;
+
+ ctxs->queue_ctx = alloc_percpu(struct blk_mq_ctx);
+ if (!ctxs->queue_ctx)
+ goto fail;
+
+ for_each_possible_cpu(cpu) {
+ struct blk_mq_ctx *ctx = per_cpu_ptr(ctxs->queue_ctx, cpu);
+ ctx->ctxs = ctxs;
+ }
+
+ q->mq_kobj = &ctxs->kobj;
+ q->queue_ctx = ctxs->queue_ctx;
+
+ return 0;
+ fail:
+ kfree(ctxs);
+ return -ENOMEM;
+}
+
/*
* It is the actual release handler for mq, but we do it from
* request queue's release handler for avoiding use-after-free
kobject_put(&hctx->kobj);
}
- q->mq_map = NULL;
-
kfree(q->queue_hw_ctx);
/*
* both share lifetime with request queue.
*/
blk_mq_sysfs_deinit(q);
-
- free_percpu(q->queue_ctx);
}
struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
{
struct request_queue *uninit_q, *q;
- uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node, NULL);
+ uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node);
if (!uninit_q)
return ERR_PTR(-ENOMEM);
memset(set, 0, sizeof(*set));
set->ops = ops;
set->nr_hw_queues = 1;
+ set->nr_maps = 1;
set->queue_depth = queue_depth;
set->numa_node = NUMA_NO_NODE;
set->flags = set_flags;
int node;
struct blk_mq_hw_ctx *hctx;
- node = blk_mq_hw_queue_to_node(q->mq_map, i);
+ node = blk_mq_hw_queue_to_node(&set->map[0], i);
/*
* If the hw queue has been mapped to another numa node,
* we need to realloc the hctx. If allocation fails, fallback
mutex_unlock(&q->sysfs_lock);
}
+/*
+ * Maximum number of hardware queues we support. For single sets, we'll never
+ * have more than the CPUs (software queues). For multiple sets, the tag_set
+ * user may have set ->nr_hw_queues larger.
+ */
+static unsigned int nr_hw_queues(struct blk_mq_tag_set *set)
+{
+ if (set->nr_maps == 1)
+ return nr_cpu_ids;
+
+ return max(set->nr_hw_queues, nr_cpu_ids);
+}
+
struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
struct request_queue *q)
{
if (!q->poll_cb)
goto err_exit;
- q->queue_ctx = alloc_percpu(struct blk_mq_ctx);
- if (!q->queue_ctx)
+ if (blk_mq_alloc_ctxs(q))
goto err_exit;
/* init q->mq_kobj and sw queues' kobjects */
blk_mq_sysfs_init(q);
- q->queue_hw_ctx = kcalloc_node(nr_cpu_ids, sizeof(*(q->queue_hw_ctx)),
+ q->nr_queues = nr_hw_queues(set);
+ q->queue_hw_ctx = kcalloc_node(q->nr_queues, sizeof(*(q->queue_hw_ctx)),
GFP_KERNEL, set->numa_node);
if (!q->queue_hw_ctx)
- goto err_percpu;
-
- q->mq_map = set->mq_map;
+ goto err_sys_init;
blk_mq_realloc_hw_ctxs(set, q);
if (!q->nr_hw_queues)
INIT_WORK(&q->timeout_work, blk_mq_timeout_work);
blk_queue_rq_timeout(q, set->timeout ? set->timeout : 30 * HZ);
- q->nr_queues = nr_cpu_ids;
+ q->tag_set = set;
q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT;
+ if (set->nr_maps > HCTX_TYPE_POLL &&
+ set->map[HCTX_TYPE_POLL].nr_queues)
+ blk_queue_flag_set(QUEUE_FLAG_POLL, q);
if (!(set->flags & BLK_MQ_F_SG_MERGE))
- queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
+ blk_queue_flag_set(QUEUE_FLAG_NO_SG_MERGE, q);
q->sg_reserved_size = INT_MAX;
spin_lock_init(&q->requeue_lock);
blk_queue_make_request(q, blk_mq_make_request);
- if (q->mq_ops->poll)
- q->poll_fn = blk_mq_poll;
/*
* Do this after blk_queue_make_request() overrides it...
*/
q->poll_nsec = -1;
- if (set->ops->complete)
- blk_queue_softirq_done(q, set->ops->complete);
-
blk_mq_init_cpu_queues(q, set->nr_hw_queues);
blk_mq_add_queue_tag_set(set, q);
blk_mq_map_swqueue(q);
err_hctxs:
kfree(q->queue_hw_ctx);
-err_percpu:
- free_percpu(q->queue_ctx);
+err_sys_init:
+ blk_mq_sysfs_deinit(q);
err_exit:
q->mq_ops = NULL;
return ERR_PTR(-ENOMEM);
static int blk_mq_update_queue_map(struct blk_mq_tag_set *set)
{
- if (set->ops->map_queues) {
+ if (set->ops->map_queues && !is_kdump_kernel()) {
+ int i;
+
/*
* transport .map_queues is usually done in the following
* way:
* for (queue = 0; queue < set->nr_hw_queues; queue++) {
* mask = get_cpu_mask(queue)
* for_each_cpu(cpu, mask)
- * set->mq_map[cpu] = queue;
+ * set->map[x].mq_map[cpu] = queue;
* }
*
* When we need to remap, the table has to be cleared for
* killing stale mapping since one CPU may not be mapped
* to any hw queue.
*/
- blk_mq_clear_mq_map(set);
+ for (i = 0; i < set->nr_maps; i++)
+ blk_mq_clear_mq_map(&set->map[i]);
return set->ops->map_queues(set);
- } else
- return blk_mq_map_queues(set);
+ } else {
+ BUG_ON(set->nr_maps > 1);
+ return blk_mq_map_queues(&set->map[0]);
+ }
}
/*
*/
int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
{
- int ret;
+ int i, ret;
BUILD_BUG_ON(BLK_MQ_MAX_DEPTH > 1 << BLK_MQ_UNIQUE_TAG_BITS);
set->queue_depth = BLK_MQ_MAX_DEPTH;
}
+ if (!set->nr_maps)
+ set->nr_maps = 1;
+ else if (set->nr_maps > HCTX_MAX_TYPES)
+ return -EINVAL;
+
/*
* If a crashdump is active, then we are potentially in a very
* memory constrained environment. Limit us to 1 queue and
*/
if (is_kdump_kernel()) {
set->nr_hw_queues = 1;
+ set->nr_maps = 1;
set->queue_depth = min(64U, set->queue_depth);
}
/*
- * There is no use for more h/w queues than cpus.
+ * There is no use for more h/w queues than cpus if we just have
+ * a single map
*/
- if (set->nr_hw_queues > nr_cpu_ids)
+ if (set->nr_maps == 1 && set->nr_hw_queues > nr_cpu_ids)
set->nr_hw_queues = nr_cpu_ids;
- set->tags = kcalloc_node(nr_cpu_ids, sizeof(struct blk_mq_tags *),
+ set->tags = kcalloc_node(nr_hw_queues(set), sizeof(struct blk_mq_tags *),
GFP_KERNEL, set->numa_node);
if (!set->tags)
return -ENOMEM;
ret = -ENOMEM;
- set->mq_map = kcalloc_node(nr_cpu_ids, sizeof(*set->mq_map),
- GFP_KERNEL, set->numa_node);
- if (!set->mq_map)
- goto out_free_tags;
+ for (i = 0; i < set->nr_maps; i++) {
+ set->map[i].mq_map = kcalloc_node(nr_cpu_ids,
+ sizeof(set->map[i].mq_map[0]),
+ GFP_KERNEL, set->numa_node);
+ if (!set->map[i].mq_map)
+ goto out_free_mq_map;
+ set->map[i].nr_queues = is_kdump_kernel() ? 1 : set->nr_hw_queues;
+ }
ret = blk_mq_update_queue_map(set);
if (ret)
return 0;
out_free_mq_map:
- kfree(set->mq_map);
- set->mq_map = NULL;
-out_free_tags:
+ for (i = 0; i < set->nr_maps; i++) {
+ kfree(set->map[i].mq_map);
+ set->map[i].mq_map = NULL;
+ }
kfree(set->tags);
set->tags = NULL;
return ret;
void blk_mq_free_tag_set(struct blk_mq_tag_set *set)
{
- int i;
+ int i, j;
- for (i = 0; i < nr_cpu_ids; i++)
+ for (i = 0; i < nr_hw_queues(set); i++)
blk_mq_free_map_and_requests(set, i);
- kfree(set->mq_map);
- set->mq_map = NULL;
+ for (j = 0; j < set->nr_maps; j++) {
+ kfree(set->map[j].mq_map);
+ set->map[j].mq_map = NULL;
+ }
kfree(set->tags);
set->tags = NULL;
lockdep_assert_held(&set->tag_list_lock);
- if (nr_hw_queues > nr_cpu_ids)
+ if (set->nr_maps == 1 && nr_hw_queues > nr_cpu_ids)
nr_hw_queues = nr_cpu_ids;
if (nr_hw_queues < 1 || nr_hw_queues == set->nr_hw_queues)
return;
pr_warn("Increasing nr_hw_queues to %d fails, fallback to %d\n",
nr_hw_queues, prev_nr_hw_queues);
set->nr_hw_queues = prev_nr_hw_queues;
- blk_mq_map_queues(set);
+ blk_mq_map_queues(&set->map[0]);
goto fallback;
}
blk_mq_map_swqueue(q);
return false;
/*
- * poll_nsec can be:
+ * If we get here, hybrid polling is enabled. Hence poll_nsec can be:
*
- * -1: don't ever hybrid sleep
* 0: use half of prev avg
* >0: use this specific value
*/
- if (q->poll_nsec == -1)
- return false;
- else if (q->poll_nsec > 0)
+ if (q->poll_nsec > 0)
nsecs = q->poll_nsec;
else
nsecs = blk_mq_poll_nsecs(q, hctx, rq);
return true;
}
-static bool __blk_mq_poll(struct blk_mq_hw_ctx *hctx, struct request *rq)
+static bool blk_mq_poll_hybrid(struct request_queue *q,
+ struct blk_mq_hw_ctx *hctx, blk_qc_t cookie)
{
- struct request_queue *q = hctx->queue;
+ struct request *rq;
+
+ if (q->poll_nsec == -1)
+ return false;
+
+ if (!blk_qc_t_is_internal(cookie))
+ rq = blk_mq_tag_to_rq(hctx->tags, blk_qc_t_to_tag(cookie));
+ else {
+ rq = blk_mq_tag_to_rq(hctx->sched_tags, blk_qc_t_to_tag(cookie));
+ /*
+ * With scheduling, if the request has completed, we'll
+ * get a NULL return here, as we clear the sched tag when
+ * that happens. The request still remains valid, like always,
+ * so we should be safe with just the NULL check.
+ */
+ if (!rq)
+ return false;
+ }
+
+ return blk_mq_poll_hybrid_sleep(q, hctx, rq);
+}
+
+/**
+ * blk_poll - poll for IO completions
+ * @q: the queue
+ * @cookie: cookie passed back at IO submission time
+ * @spin: whether to spin for completions
+ *
+ * Description:
+ * Poll for completions on the passed in queue. Returns number of
+ * completed entries found. If @spin is true, then blk_poll will continue
+ * looping until at least one completion is found, unless the task is
+ * otherwise marked running (or we need to reschedule).
+ */
+int blk_poll(struct request_queue *q, blk_qc_t cookie, bool spin)
+{
+ struct blk_mq_hw_ctx *hctx;
long state;
+ if (!blk_qc_t_valid(cookie) ||
+ !test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
+ return 0;
+
+ if (current->plug)
+ blk_flush_plug_list(current->plug, false);
+
+ hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)];
+
/*
* If we sleep, have the caller restart the poll loop to reset
* the state. Like for the other success return cases, the
* the IO isn't complete, we'll get called again and will go
* straight to the busy poll loop.
*/
- if (blk_mq_poll_hybrid_sleep(q, hctx, rq))
- return true;
+ if (blk_mq_poll_hybrid(q, hctx, cookie))
+ return 1;
hctx->poll_considered++;
state = current->state;
- while (!need_resched()) {
+ do {
int ret;
hctx->poll_invoked++;
- ret = q->mq_ops->poll(hctx, rq->tag);
+ ret = q->mq_ops->poll(hctx);
if (ret > 0) {
hctx->poll_success++;
- set_current_state(TASK_RUNNING);
- return true;
+ __set_current_state(TASK_RUNNING);
+ return ret;
}
if (signal_pending_state(state, current))
- set_current_state(TASK_RUNNING);
+ __set_current_state(TASK_RUNNING);
if (current->state == TASK_RUNNING)
- return true;
- if (ret < 0)
+ return 1;
+ if (ret < 0 || !spin)
break;
cpu_relax();
- }
+ } while (!need_resched());
__set_current_state(TASK_RUNNING);
- return false;
+ return 0;
}
+EXPORT_SYMBOL_GPL(blk_poll);
-static bool blk_mq_poll(struct request_queue *q, blk_qc_t cookie)
+unsigned int blk_mq_rq_cpu(struct request *rq)
{
- struct blk_mq_hw_ctx *hctx;
- struct request *rq;
-
- if (!test_bit(QUEUE_FLAG_POLL, &q->queue_flags))
- return false;
-
- hctx = q->queue_hw_ctx[blk_qc_t_to_queue_num(cookie)];
- if (!blk_qc_t_is_internal(cookie))
- rq = blk_mq_tag_to_rq(hctx->tags, blk_qc_t_to_tag(cookie));
- else {
- rq = blk_mq_tag_to_rq(hctx->sched_tags, blk_qc_t_to_tag(cookie));
- /*
- * With scheduling, if the request has completed, we'll
- * get a NULL return here, as we clear the sched tag when
- * that happens. The request still remains valid, like always,
- * so we should be safe with just the NULL check.
- */
- if (!rq)
- return false;
- }
-
- return __blk_mq_poll(hctx, rq);
+ return rq->mq_ctx->cpu;
}
+EXPORT_SYMBOL(blk_mq_rq_cpu);
static int __init blk_mq_init(void)
{
projects / linux.git / blobdiff