+/*
+ * Block multiqueue core code
+ *
+ * Copyright (C) 2013-2014 Jens Axboe
+ * Copyright (C) 2013-2014 Christoph Hellwig
+ */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
{
unsigned int i;
- for (i = 0; i < hctx->nr_ctx_map; i++)
- if (hctx->ctx_map[i])
+ for (i = 0; i < hctx->ctx_map.map_size; i++)
+ if (hctx->ctx_map.map[i].word)
return true;
return false;
}
+static inline struct blk_align_bitmap *get_bm(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *ctx)
+{
+ return &hctx->ctx_map.map[ctx->index_hw / hctx->ctx_map.bits_per_word];
+}
+
+#define CTX_TO_BIT(hctx, ctx) \
+ ((ctx)->index_hw & ((hctx)->ctx_map.bits_per_word - 1))
+
/*
* Mark this ctx as having pending work in this hardware queue
*/
static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx)
{
- if (!test_bit(ctx->index_hw, hctx->ctx_map))
- set_bit(ctx->index_hw, hctx->ctx_map);
+ struct blk_align_bitmap *bm = get_bm(hctx, ctx);
+
+ if (!test_bit(CTX_TO_BIT(hctx, ctx), &bm->word))
+ set_bit(CTX_TO_BIT(hctx, ctx), &bm->word);
}
-static struct request *__blk_mq_alloc_request(struct blk_mq_hw_ctx *hctx,
- gfp_t gfp, bool reserved)
+static void blk_mq_hctx_clear_pending(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *ctx)
{
- struct request *rq;
- unsigned int tag;
-
- tag = blk_mq_get_tag(hctx->tags, gfp, reserved);
- if (tag != BLK_MQ_TAG_FAIL) {
- rq = hctx->rqs[tag];
- rq->tag = tag;
-
- return rq;
- }
+ struct blk_align_bitmap *bm = get_bm(hctx, ctx);
- return NULL;
+ clear_bit(CTX_TO_BIT(hctx, ctx), &bm->word);
}
static int blk_mq_queue_enter(struct request_queue *q)
if (blk_queue_io_stat(q))
rw_flags |= REQ_IO_STAT;
+ INIT_LIST_HEAD(&rq->queuelist);
+ /* csd/requeue_work/fifo_time is initialized before use */
+ rq->q = q;
rq->mq_ctx = ctx;
- rq->cmd_flags = rw_flags;
+ rq->cmd_flags |= rw_flags;
+ rq->cmd_type = 0;
+ /* do not touch atomic flags, it needs atomic ops against the timer */
+ rq->cpu = -1;
+ rq->__data_len = 0;
+ rq->__sector = (sector_t) -1;
+ rq->bio = NULL;
+ rq->biotail = NULL;
+ INIT_HLIST_NODE(&rq->hash);
+ RB_CLEAR_NODE(&rq->rb_node);
+ memset(&rq->flush, 0, max(sizeof(rq->flush), sizeof(rq->elv)));
+ rq->rq_disk = NULL;
+ rq->part = NULL;
rq->start_time = jiffies;
+#ifdef CONFIG_BLK_CGROUP
+ rq->rl = NULL;
set_start_time_ns(rq);
+ rq->io_start_time_ns = 0;
+#endif
+ rq->nr_phys_segments = 0;
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+ rq->nr_integrity_segments = 0;
+#endif
+ rq->ioprio = 0;
+ rq->special = NULL;
+ /* tag was already set */
+ rq->errors = 0;
+ memset(rq->__cmd, 0, sizeof(rq->__cmd));
+ rq->cmd = rq->__cmd;
+ rq->cmd_len = BLK_MAX_CDB;
+
+ rq->extra_len = 0;
+ rq->sense_len = 0;
+ rq->resid_len = 0;
+ rq->sense = NULL;
+
+ rq->deadline = 0;
+ INIT_LIST_HEAD(&rq->timeout_list);
+ rq->timeout = 0;
+ rq->retries = 0;
+ rq->end_io = NULL;
+ rq->end_io_data = NULL;
+ rq->next_rq = NULL;
+
ctx->rq_dispatched[rw_is_sync(rw_flags)]++;
}
-static struct request *blk_mq_alloc_request_pinned(struct request_queue *q,
- int rw, gfp_t gfp,
- bool reserved)
+static struct request *
+__blk_mq_alloc_request(struct request_queue *q, struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *ctx, int rw, gfp_t gfp, bool reserved)
{
struct request *rq;
+ unsigned int tag;
- do {
- struct blk_mq_ctx *ctx = blk_mq_get_ctx(q);
- struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, ctx->cpu);
+ tag = blk_mq_get_tag(hctx, &ctx->last_tag, gfp, reserved);
+ if (tag != BLK_MQ_TAG_FAIL) {
+ rq = hctx->tags->rqs[tag];
- rq = __blk_mq_alloc_request(hctx, gfp & ~__GFP_WAIT, reserved);
- if (rq) {
- blk_mq_rq_ctx_init(q, ctx, rq, rw);
- break;
+ rq->cmd_flags = 0;
+ if (blk_mq_tag_busy(hctx)) {
+ rq->cmd_flags = REQ_MQ_INFLIGHT;
+ atomic_inc(&hctx->nr_active);
}
- blk_mq_put_ctx(ctx);
- if (!(gfp & __GFP_WAIT))
- break;
-
- __blk_mq_run_hw_queue(hctx);
- blk_mq_wait_for_tags(hctx->tags);
- } while (1);
+ rq->tag = tag;
+ blk_mq_rq_ctx_init(q, ctx, rq, rw);
+ return rq;
+ }
- return rq;
+ return NULL;
}
-struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp)
+struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp,
+ bool reserved)
{
+ struct blk_mq_ctx *ctx;
+ struct blk_mq_hw_ctx *hctx;
struct request *rq;
if (blk_mq_queue_enter(q))
return NULL;
- rq = blk_mq_alloc_request_pinned(q, rw, gfp, false);
- if (rq)
- blk_mq_put_ctx(rq->mq_ctx);
- return rq;
-}
-
-struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw,
- gfp_t gfp)
-{
- struct request *rq;
+ ctx = blk_mq_get_ctx(q);
+ hctx = q->mq_ops->map_queue(q, ctx->cpu);
- if (blk_mq_queue_enter(q))
- return NULL;
+ rq = __blk_mq_alloc_request(q, hctx, ctx, rw, gfp & ~__GFP_WAIT,
+ reserved);
+ if (!rq && (gfp & __GFP_WAIT)) {
+ __blk_mq_run_hw_queue(hctx);
+ blk_mq_put_ctx(ctx);
- rq = blk_mq_alloc_request_pinned(q, rw, gfp, true);
- if (rq)
- blk_mq_put_ctx(rq->mq_ctx);
+ ctx = blk_mq_get_ctx(q);
+ hctx = q->mq_ops->map_queue(q, ctx->cpu);
+ rq = __blk_mq_alloc_request(q, hctx, ctx, rw, gfp, reserved);
+ }
+ blk_mq_put_ctx(ctx);
return rq;
}
-EXPORT_SYMBOL(blk_mq_alloc_reserved_request);
-
-/*
- * Re-init and set pdu, if we have it
- */
-void blk_mq_rq_init(struct blk_mq_hw_ctx *hctx, struct request *rq)
-{
- blk_rq_init(hctx->queue, rq);
-
- if (hctx->cmd_size)
- rq->special = blk_mq_rq_to_pdu(rq);
-}
+EXPORT_SYMBOL(blk_mq_alloc_request);
static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx, struct request *rq)
const int tag = rq->tag;
struct request_queue *q = rq->q;
- blk_mq_rq_init(hctx, rq);
- blk_mq_put_tag(hctx->tags, tag);
+ if (rq->cmd_flags & REQ_MQ_INFLIGHT)
+ atomic_dec(&hctx->nr_active);
+ clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
+ blk_mq_put_tag(hctx, tag, &ctx->last_tag);
blk_mq_queue_exit(q);
}
__blk_mq_free_request(hctx, ctx, rq);
}
-bool blk_mq_end_io_partial(struct request *rq, int error, unsigned int nr_bytes)
+/*
+ * Clone all relevant state from a request that has been put on hold in
+ * the flush state machine into the preallocated flush request that hangs
+ * off the request queue.
+ *
+ * For a driver the flush request should be invisible, that's why we are
+ * impersonating the original request here.
+ */
+void blk_mq_clone_flush_request(struct request *flush_rq,
+ struct request *orig_rq)
{
- if (blk_update_request(rq, error, blk_rq_bytes(rq)))
- return true;
+ struct blk_mq_hw_ctx *hctx =
+ orig_rq->q->mq_ops->map_queue(orig_rq->q, orig_rq->mq_ctx->cpu);
+
+ flush_rq->mq_ctx = orig_rq->mq_ctx;
+ flush_rq->tag = orig_rq->tag;
+ memcpy(blk_mq_rq_to_pdu(flush_rq), blk_mq_rq_to_pdu(orig_rq),
+ hctx->cmd_size);
+}
+inline void __blk_mq_end_io(struct request *rq, int error)
+{
blk_account_io_done(rq);
- if (rq->end_io)
+ if (rq->end_io) {
rq->end_io(rq, error);
- else
+ } else {
+ if (unlikely(blk_bidi_rq(rq)))
+ blk_mq_free_request(rq->next_rq);
blk_mq_free_request(rq);
- return false;
+ }
+}
+EXPORT_SYMBOL(__blk_mq_end_io);
+
+void blk_mq_end_io(struct request *rq, int error)
+{
+ if (blk_update_request(rq, error, blk_rq_bytes(rq)))
+ BUG();
+ __blk_mq_end_io(rq, error);
}
-EXPORT_SYMBOL(blk_mq_end_io_partial);
+EXPORT_SYMBOL(blk_mq_end_io);
static void __blk_mq_complete_request_remote(void *data)
{
void __blk_mq_complete_request(struct request *rq)
{
struct blk_mq_ctx *ctx = rq->mq_ctx;
+ bool shared = false;
int cpu;
- if (!ctx->ipi_redirect) {
+ if (!test_bit(QUEUE_FLAG_SAME_COMP, &rq->q->queue_flags)) {
rq->q->softirq_done_fn(rq);
return;
}
cpu = get_cpu();
- if (cpu != ctx->cpu && cpu_online(ctx->cpu)) {
+ if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags))
+ shared = cpus_share_cache(cpu, ctx->cpu);
+
+ if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) {
rq->csd.func = __blk_mq_complete_request_remote;
rq->csd.info = rq;
rq->csd.flags = 0;
**/
void blk_mq_complete_request(struct request *rq)
{
- if (unlikely(blk_should_fake_timeout(rq->q)))
+ struct request_queue *q = rq->q;
+
+ if (unlikely(blk_should_fake_timeout(q)))
return;
- if (!blk_mark_rq_complete(rq))
- __blk_mq_complete_request(rq);
+ if (!blk_mark_rq_complete(rq)) {
+ if (q->softirq_done_fn)
+ __blk_mq_complete_request(rq);
+ else
+ blk_mq_end_io(rq, rq->errors);
+ }
}
EXPORT_SYMBOL(blk_mq_complete_request);
trace_block_rq_issue(q, rq);
+ rq->resid_len = blk_rq_bytes(rq);
+ if (unlikely(blk_bidi_rq(rq)))
+ rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq);
+
/*
* Just mark start time and set the started bit. Due to memory
* ordering, we know we'll see the correct deadline as long as
- * REQ_ATOMIC_STARTED is seen.
+ * REQ_ATOMIC_STARTED is seen. Use the default queue timeout,
+ * unless one has been set in the request.
+ */
+ if (!rq->timeout)
+ rq->deadline = jiffies + q->rq_timeout;
+ else
+ rq->deadline = jiffies + rq->timeout;
+
+ /*
+ * Mark us as started and clear complete. Complete might have been
+ * set if requeue raced with timeout, which then marked it as
+ * complete. So be sure to clear complete again when we start
+ * the request, otherwise we'll ignore the completion event.
*/
- rq->deadline = jiffies + q->rq_timeout;
set_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
+ clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags);
if (q->dma_drain_size && blk_rq_bytes(rq)) {
/*
rq->cmd_flags |= REQ_END;
}
-static void blk_mq_requeue_request(struct request *rq)
+static void __blk_mq_requeue_request(struct request *rq)
{
struct request_queue *q = rq->q;
rq->nr_phys_segments--;
}
+void blk_mq_requeue_request(struct request *rq)
+{
+ __blk_mq_requeue_request(rq);
+ blk_clear_rq_complete(rq);
+
+ BUG_ON(blk_queued_rq(rq));
+ blk_mq_add_to_requeue_list(rq, true);
+}
+EXPORT_SYMBOL(blk_mq_requeue_request);
+
+static void blk_mq_requeue_work(struct work_struct *work)
+{
+ struct request_queue *q =
+ container_of(work, struct request_queue, requeue_work);
+ LIST_HEAD(rq_list);
+ struct request *rq, *next;
+ unsigned long flags;
+
+ spin_lock_irqsave(&q->requeue_lock, flags);
+ list_splice_init(&q->requeue_list, &rq_list);
+ spin_unlock_irqrestore(&q->requeue_lock, flags);
+
+ list_for_each_entry_safe(rq, next, &rq_list, queuelist) {
+ if (!(rq->cmd_flags & REQ_SOFTBARRIER))
+ continue;
+
+ rq->cmd_flags &= ~REQ_SOFTBARRIER;
+ list_del_init(&rq->queuelist);
+ blk_mq_insert_request(rq, true, false, false);
+ }
+
+ while (!list_empty(&rq_list)) {
+ rq = list_entry(rq_list.next, struct request, queuelist);
+ list_del_init(&rq->queuelist);
+ blk_mq_insert_request(rq, false, false, false);
+ }
+
+ blk_mq_run_queues(q, false);
+}
+
+void blk_mq_add_to_requeue_list(struct request *rq, bool at_head)
+{
+ struct request_queue *q = rq->q;
+ unsigned long flags;
+
+ /*
+ * We abuse this flag that is otherwise used by the I/O scheduler to
+ * request head insertation from the workqueue.
+ */
+ BUG_ON(rq->cmd_flags & REQ_SOFTBARRIER);
+
+ spin_lock_irqsave(&q->requeue_lock, flags);
+ if (at_head) {
+ rq->cmd_flags |= REQ_SOFTBARRIER;
+ list_add(&rq->queuelist, &q->requeue_list);
+ } else {
+ list_add_tail(&rq->queuelist, &q->requeue_list);
+ }
+ spin_unlock_irqrestore(&q->requeue_lock, flags);
+}
+EXPORT_SYMBOL(blk_mq_add_to_requeue_list);
+
+void blk_mq_kick_requeue_list(struct request_queue *q)
+{
+ kblockd_schedule_work(&q->requeue_work);
+}
+EXPORT_SYMBOL(blk_mq_kick_requeue_list);
+
+struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag)
+{
+ return tags->rqs[tag];
+}
+EXPORT_SYMBOL(blk_mq_tag_to_rq);
+
struct blk_mq_timeout_data {
struct blk_mq_hw_ctx *hctx;
unsigned long *next;
do {
struct request *rq;
- tag = find_next_zero_bit(free_tags, hctx->queue_depth, tag);
- if (tag >= hctx->queue_depth)
+ tag = find_next_zero_bit(free_tags, hctx->tags->nr_tags, tag);
+ if (tag >= hctx->tags->nr_tags)
break;
- rq = hctx->rqs[tag++];
-
+ rq = blk_mq_tag_to_rq(hctx->tags, tag++);
+ if (rq->q != hctx->queue)
+ continue;
if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
continue;
blk_mq_tag_busy_iter(hctx->tags, blk_mq_timeout_check, &data);
}
+static enum blk_eh_timer_return blk_mq_rq_timed_out(struct request *rq)
+{
+ struct request_queue *q = rq->q;
+
+ /*
+ * We know that complete is set at this point. If STARTED isn't set
+ * anymore, then the request isn't active and the "timeout" should
+ * just be ignored. This can happen due to the bitflag ordering.
+ * Timeout first checks if STARTED is set, and if it is, assumes
+ * the request is active. But if we race with completion, then
+ * we both flags will get cleared. So check here again, and ignore
+ * a timeout event with a request that isn't active.
+ */
+ if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
+ return BLK_EH_NOT_HANDLED;
+
+ if (!q->mq_ops->timeout)
+ return BLK_EH_RESET_TIMER;
+
+ return q->mq_ops->timeout(rq);
+}
+
static void blk_mq_rq_timer(unsigned long data)
{
struct request_queue *q = (struct request_queue *) data;
unsigned long next = 0;
int i, next_set = 0;
- queue_for_each_hw_ctx(q, hctx, i)
+ queue_for_each_hw_ctx(q, hctx, i) {
+ /*
+ * If not software queues are currently mapped to this
+ * hardware queue, there's nothing to check
+ */
+ if (!hctx->nr_ctx || !hctx->tags)
+ continue;
+
blk_mq_hw_ctx_check_timeout(hctx, &next, &next_set);
+ }
- if (next_set)
- mod_timer(&q->timeout, round_jiffies_up(next));
+ if (next_set) {
+ next = blk_rq_timeout(round_jiffies_up(next));
+ mod_timer(&q->timeout, next);
+ } else {
+ queue_for_each_hw_ctx(q, hctx, i)
+ blk_mq_tag_idle(hctx);
+ }
}
/*
return false;
}
-void blk_mq_add_timer(struct request *rq)
+/*
+ * Process software queues that have been marked busy, splicing them
+ * to the for-dispatch
+ */
+static void flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list)
{
- __blk_add_timer(rq, NULL);
+ struct blk_mq_ctx *ctx;
+ int i;
+
+ for (i = 0; i < hctx->ctx_map.map_size; i++) {
+ struct blk_align_bitmap *bm = &hctx->ctx_map.map[i];
+ unsigned int off, bit;
+
+ if (!bm->word)
+ continue;
+
+ bit = 0;
+ off = i * hctx->ctx_map.bits_per_word;
+ do {
+ bit = find_next_bit(&bm->word, bm->depth, bit);
+ if (bit >= bm->depth)
+ break;
+
+ ctx = hctx->ctxs[bit + off];
+ clear_bit(bit, &bm->word);
+ spin_lock(&ctx->lock);
+ list_splice_tail_init(&ctx->rq_list, list);
+ spin_unlock(&ctx->lock);
+
+ bit++;
+ } while (1);
+ }
}
/*
static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx)
{
struct request_queue *q = hctx->queue;
- struct blk_mq_ctx *ctx;
struct request *rq;
LIST_HEAD(rq_list);
- int bit, queued;
+ int queued;
+
+ WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask));
if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state)))
return;
/*
* Touch any software queue that has pending entries.
*/
- for_each_set_bit(bit, hctx->ctx_map, hctx->nr_ctx) {
- clear_bit(bit, hctx->ctx_map);
- ctx = hctx->ctxs[bit];
- BUG_ON(bit != ctx->index_hw);
-
- spin_lock(&ctx->lock);
- list_splice_tail_init(&ctx->rq_list, &rq_list);
- spin_unlock(&ctx->lock);
- }
+ flush_busy_ctxs(hctx, &rq_list);
/*
* If we have previous entries on our dispatch list, grab them
spin_unlock(&hctx->lock);
}
- /*
- * Delete and return all entries from our dispatch list
- */
- queued = 0;
-
/*
* Now process all the entries, sending them to the driver.
*/
+ queued = 0;
while (!list_empty(&rq_list)) {
int ret;
queued++;
continue;
case BLK_MQ_RQ_QUEUE_BUSY:
- /*
- * FIXME: we should have a mechanism to stop the queue
- * like blk_stop_queue, otherwise we will waste cpu
- * time
- */
list_add(&rq->queuelist, &rq_list);
- blk_mq_requeue_request(rq);
+ __blk_mq_requeue_request(rq);
break;
default:
pr_err("blk-mq: bad return on queue: %d\n", ret);
}
}
+/*
+ * It'd be great if the workqueue API had a way to pass
+ * in a mask and had some smarts for more clever placement.
+ * For now we just round-robin here, switching for every
+ * BLK_MQ_CPU_WORK_BATCH queued items.
+ */
+static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx)
+{
+ int cpu = hctx->next_cpu;
+
+ if (--hctx->next_cpu_batch <= 0) {
+ int next_cpu;
+
+ next_cpu = cpumask_next(hctx->next_cpu, hctx->cpumask);
+ if (next_cpu >= nr_cpu_ids)
+ next_cpu = cpumask_first(hctx->cpumask);
+
+ hctx->next_cpu = next_cpu;
+ hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH;
+ }
+
+ return cpu;
+}
+
void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
{
if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state)))
return;
- if (!async)
+ if (!async && cpumask_test_cpu(smp_processor_id(), hctx->cpumask))
__blk_mq_run_hw_queue(hctx);
+ else if (hctx->queue->nr_hw_queues == 1)
+ kblockd_schedule_delayed_work(&hctx->run_work, 0);
else {
- struct request_queue *q = hctx->queue;
+ unsigned int cpu;
- kblockd_schedule_delayed_work(q, &hctx->delayed_work, 0);
+ cpu = blk_mq_hctx_next_cpu(hctx);
+ kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0);
}
}
test_bit(BLK_MQ_S_STOPPED, &hctx->state))
continue;
+ preempt_disable();
blk_mq_run_hw_queue(hctx, async);
+ preempt_enable();
}
}
EXPORT_SYMBOL(blk_mq_run_queues);
void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx)
{
- cancel_delayed_work(&hctx->delayed_work);
+ cancel_delayed_work(&hctx->run_work);
+ cancel_delayed_work(&hctx->delay_work);
set_bit(BLK_MQ_S_STOPPED, &hctx->state);
}
EXPORT_SYMBOL(blk_mq_stop_hw_queue);
void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx)
{
clear_bit(BLK_MQ_S_STOPPED, &hctx->state);
+
+ preempt_disable();
__blk_mq_run_hw_queue(hctx);
+ preempt_enable();
}
EXPORT_SYMBOL(blk_mq_start_hw_queue);
-void blk_mq_start_stopped_hw_queues(struct request_queue *q)
+void blk_mq_start_hw_queues(struct request_queue *q)
+{
+ struct blk_mq_hw_ctx *hctx;
+ int i;
+
+ queue_for_each_hw_ctx(q, hctx, i)
+ blk_mq_start_hw_queue(hctx);
+}
+EXPORT_SYMBOL(blk_mq_start_hw_queues);
+
+
+void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async)
{
struct blk_mq_hw_ctx *hctx;
int i;
continue;
clear_bit(BLK_MQ_S_STOPPED, &hctx->state);
- blk_mq_run_hw_queue(hctx, true);
+ preempt_disable();
+ blk_mq_run_hw_queue(hctx, async);
+ preempt_enable();
}
}
EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues);
-static void blk_mq_work_fn(struct work_struct *work)
+static void blk_mq_run_work_fn(struct work_struct *work)
{
struct blk_mq_hw_ctx *hctx;
- hctx = container_of(work, struct blk_mq_hw_ctx, delayed_work.work);
+ hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work);
+
__blk_mq_run_hw_queue(hctx);
}
+static void blk_mq_delay_work_fn(struct work_struct *work)
+{
+ struct blk_mq_hw_ctx *hctx;
+
+ hctx = container_of(work, struct blk_mq_hw_ctx, delay_work.work);
+
+ if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state))
+ __blk_mq_run_hw_queue(hctx);
+}
+
+void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs)
+{
+ unsigned long tmo = msecs_to_jiffies(msecs);
+
+ if (hctx->queue->nr_hw_queues == 1)
+ kblockd_schedule_delayed_work(&hctx->delay_work, tmo);
+ else {
+ unsigned int cpu;
+
+ cpu = blk_mq_hctx_next_cpu(hctx);
+ kblockd_schedule_delayed_work_on(cpu, &hctx->delay_work, tmo);
+ }
+}
+EXPORT_SYMBOL(blk_mq_delay_queue);
+
static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx,
struct request *rq, bool at_head)
{
list_add(&rq->queuelist, &ctx->rq_list);
else
list_add_tail(&rq->queuelist, &ctx->rq_list);
+
blk_mq_hctx_mark_pending(hctx, ctx);
/*
* We do this early, to ensure we are on the right CPU.
*/
- blk_mq_add_timer(rq);
+ blk_add_timer(rq);
}
void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue,
spin_unlock(&ctx->lock);
}
- blk_mq_put_ctx(current_ctx);
-
if (run_queue)
blk_mq_run_hw_queue(hctx, async);
+
+ blk_mq_put_ctx(current_ctx);
}
static void blk_mq_insert_requests(struct request_queue *q,
}
spin_unlock(&ctx->lock);
- blk_mq_put_ctx(current_ctx);
-
blk_mq_run_hw_queue(hctx, from_schedule);
+ blk_mq_put_ctx(current_ctx);
}
static int plug_ctx_cmp(void *priv, struct list_head *a, struct list_head *b)
blk_account_io_start(rq, 1);
}
-static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
+static inline bool blk_mq_merge_queue_io(struct blk_mq_hw_ctx *hctx,
+ struct blk_mq_ctx *ctx,
+ struct request *rq, struct bio *bio)
{
- struct blk_mq_hw_ctx *hctx;
- struct blk_mq_ctx *ctx;
- const int is_sync = rw_is_sync(bio->bi_rw);
- const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA);
- int rw = bio_data_dir(bio);
- struct request *rq;
- unsigned int use_plug, request_count = 0;
-
- /*
- * If we have multiple hardware queues, just go directly to
- * one of those for sync IO.
- */
- use_plug = !is_flush_fua && ((q->nr_hw_queues == 1) || !is_sync);
+ struct request_queue *q = hctx->queue;
- blk_queue_bounce(q, &bio);
+ if (!(hctx->flags & BLK_MQ_F_SHOULD_MERGE)) {
+ blk_mq_bio_to_request(rq, bio);
+ spin_lock(&ctx->lock);
+insert_rq:
+ __blk_mq_insert_request(hctx, rq, false);
+ spin_unlock(&ctx->lock);
+ return false;
+ } else {
+ spin_lock(&ctx->lock);
+ if (!blk_mq_attempt_merge(q, ctx, bio)) {
+ blk_mq_bio_to_request(rq, bio);
+ goto insert_rq;
+ }
- if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
- bio_endio(bio, -EIO);
- return;
+ spin_unlock(&ctx->lock);
+ __blk_mq_free_request(hctx, ctx, rq);
+ return true;
}
+}
- if (use_plug && blk_attempt_plug_merge(q, bio, &request_count))
- return;
+struct blk_map_ctx {
+ struct blk_mq_hw_ctx *hctx;
+ struct blk_mq_ctx *ctx;
+};
+
+static struct request *blk_mq_map_request(struct request_queue *q,
+ struct bio *bio,
+ struct blk_map_ctx *data)
+{
+ struct blk_mq_hw_ctx *hctx;
+ struct blk_mq_ctx *ctx;
+ struct request *rq;
+ int rw = bio_data_dir(bio);
- if (blk_mq_queue_enter(q)) {
+ if (unlikely(blk_mq_queue_enter(q))) {
bio_endio(bio, -EIO);
- return;
+ return NULL;
}
ctx = blk_mq_get_ctx(q);
hctx = q->mq_ops->map_queue(q, ctx->cpu);
- if (is_sync)
+ if (rw_is_sync(bio->bi_rw))
rw |= REQ_SYNC;
+
trace_block_getrq(q, bio, rw);
- rq = __blk_mq_alloc_request(hctx, GFP_ATOMIC, false);
- if (likely(rq))
- blk_mq_rq_ctx_init(q, ctx, rq, rw);
- else {
+ rq = __blk_mq_alloc_request(q, hctx, ctx, rw, GFP_ATOMIC, false);
+ if (unlikely(!rq)) {
+ __blk_mq_run_hw_queue(hctx);
blk_mq_put_ctx(ctx);
trace_block_sleeprq(q, bio, rw);
- rq = blk_mq_alloc_request_pinned(q, rw, __GFP_WAIT|GFP_ATOMIC,
- false);
- ctx = rq->mq_ctx;
+
+ ctx = blk_mq_get_ctx(q);
hctx = q->mq_ops->map_queue(q, ctx->cpu);
+ rq = __blk_mq_alloc_request(q, hctx, ctx, rw,
+ __GFP_WAIT|GFP_ATOMIC, false);
}
hctx->queued++;
+ data->hctx = hctx;
+ data->ctx = ctx;
+ return rq;
+}
- if (unlikely(is_flush_fua)) {
- blk_mq_bio_to_request(rq, bio);
- blk_mq_put_ctx(ctx);
+/*
+ * Multiple hardware queue variant. This will not use per-process plugs,
+ * but will attempt to bypass the hctx queueing if we can go straight to
+ * hardware for SYNC IO.
+ */
+static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
+{
+ const int is_sync = rw_is_sync(bio->bi_rw);
+ const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA);
+ struct blk_map_ctx data;
+ struct request *rq;
+
+ blk_queue_bounce(q, &bio);
+
+ if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
+ bio_endio(bio, -EIO);
+ return;
+ }
+
+ rq = blk_mq_map_request(q, bio, &data);
+ if (unlikely(!rq))
+ return;
+
+ if (unlikely(is_flush_fua)) {
+ blk_mq_bio_to_request(rq, bio);
+ blk_insert_flush(rq);
+ goto run_queue;
+ }
+
+ if (is_sync) {
+ int ret;
+
+ blk_mq_bio_to_request(rq, bio);
+ blk_mq_start_request(rq, true);
+
+ /*
+ * For OK queue, we are done. For error, kill it. Any other
+ * error (busy), just add it to our list as we previously
+ * would have done
+ */
+ ret = q->mq_ops->queue_rq(data.hctx, rq);
+ if (ret == BLK_MQ_RQ_QUEUE_OK)
+ goto done;
+ else {
+ __blk_mq_requeue_request(rq);
+
+ if (ret == BLK_MQ_RQ_QUEUE_ERROR) {
+ rq->errors = -EIO;
+ blk_mq_end_io(rq, rq->errors);
+ goto done;
+ }
+ }
+ }
+
+ if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) {
+ /*
+ * For a SYNC request, send it to the hardware immediately. For
+ * an ASYNC request, just ensure that we run it later on. The
+ * latter allows for merging opportunities and more efficient
+ * dispatching.
+ */
+run_queue:
+ blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua);
+ }
+done:
+ blk_mq_put_ctx(data.ctx);
+}
+
+/*
+ * Single hardware queue variant. This will attempt to use any per-process
+ * plug for merging and IO deferral.
+ */
+static void blk_sq_make_request(struct request_queue *q, struct bio *bio)
+{
+ const int is_sync = rw_is_sync(bio->bi_rw);
+ const int is_flush_fua = bio->bi_rw & (REQ_FLUSH | REQ_FUA);
+ unsigned int use_plug, request_count = 0;
+ struct blk_map_ctx data;
+ struct request *rq;
+
+ /*
+ * If we have multiple hardware queues, just go directly to
+ * one of those for sync IO.
+ */
+ use_plug = !is_flush_fua && !is_sync;
+
+ blk_queue_bounce(q, &bio);
+
+ if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) {
+ bio_endio(bio, -EIO);
+ return;
+ }
+
+ if (use_plug && !blk_queue_nomerges(q) &&
+ blk_attempt_plug_merge(q, bio, &request_count))
+ return;
+
+ rq = blk_mq_map_request(q, bio, &data);
+
+ if (unlikely(is_flush_fua)) {
+ blk_mq_bio_to_request(rq, bio);
blk_insert_flush(rq);
goto run_queue;
}
trace_block_plug(q);
}
list_add_tail(&rq->queuelist, &plug->mq_list);
- blk_mq_put_ctx(ctx);
+ blk_mq_put_ctx(data.ctx);
return;
}
}
- spin_lock(&ctx->lock);
-
- if ((hctx->flags & BLK_MQ_F_SHOULD_MERGE) &&
- blk_mq_attempt_merge(q, ctx, bio))
- __blk_mq_free_request(hctx, ctx, rq);
- else {
- blk_mq_bio_to_request(rq, bio);
- __blk_mq_insert_request(hctx, rq, false);
+ if (!blk_mq_merge_queue_io(data.hctx, data.ctx, rq, bio)) {
+ /*
+ * For a SYNC request, send it to the hardware immediately. For
+ * an ASYNC request, just ensure that we run it later on. The
+ * latter allows for merging opportunities and more efficient
+ * dispatching.
+ */
+run_queue:
+ blk_mq_run_hw_queue(data.hctx, !is_sync || is_flush_fua);
}
- spin_unlock(&ctx->lock);
- blk_mq_put_ctx(ctx);
-
- /*
- * For a SYNC request, send it to the hardware immediately. For an
- * ASYNC request, just ensure that we run it later on. The latter
- * allows for merging opportunities and more efficient dispatching.
- */
-run_queue:
- blk_mq_run_hw_queue(hctx, !is_sync || is_flush_fua);
+ blk_mq_put_ctx(data.ctx);
}
/*
}
EXPORT_SYMBOL(blk_mq_map_queue);
-struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_reg *reg,
- unsigned int hctx_index)
+static void blk_mq_free_rq_map(struct blk_mq_tag_set *set,
+ struct blk_mq_tags *tags, unsigned int hctx_idx)
{
- return kmalloc_node(sizeof(struct blk_mq_hw_ctx),
- GFP_KERNEL | __GFP_ZERO, reg->numa_node);
+ struct page *page;
+
+ if (tags->rqs && set->ops->exit_request) {
+ int i;
+
+ for (i = 0; i < tags->nr_tags; i++) {
+ if (!tags->rqs[i])
+ continue;
+ set->ops->exit_request(set->driver_data, tags->rqs[i],
+ hctx_idx, i);
+ }
+ }
+
+ while (!list_empty(&tags->page_list)) {
+ page = list_first_entry(&tags->page_list, struct page, lru);
+ list_del_init(&page->lru);
+ __free_pages(page, page->private);
+ }
+
+ kfree(tags->rqs);
+
+ blk_mq_free_tags(tags);
}
-EXPORT_SYMBOL(blk_mq_alloc_single_hw_queue);
-void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *hctx,
- unsigned int hctx_index)
+static size_t order_to_size(unsigned int order)
{
- kfree(hctx);
+ return (size_t)PAGE_SIZE << order;
}
-EXPORT_SYMBOL(blk_mq_free_single_hw_queue);
-static void blk_mq_hctx_notify(void *data, unsigned long action,
- unsigned int cpu)
+static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set,
+ unsigned int hctx_idx)
+{
+ struct blk_mq_tags *tags;
+ unsigned int i, j, entries_per_page, max_order = 4;
+ size_t rq_size, left;
+
+ tags = blk_mq_init_tags(set->queue_depth, set->reserved_tags,
+ set->numa_node);
+ if (!tags)
+ return NULL;
+
+ INIT_LIST_HEAD(&tags->page_list);
+
+ tags->rqs = kmalloc_node(set->queue_depth * sizeof(struct request *),
+ GFP_KERNEL, set->numa_node);
+ if (!tags->rqs) {
+ blk_mq_free_tags(tags);
+ return NULL;
+ }
+
+ /*
+ * rq_size is the size of the request plus driver payload, rounded
+ * to the cacheline size
+ */
+ rq_size = round_up(sizeof(struct request) + set->cmd_size,
+ cache_line_size());
+ left = rq_size * set->queue_depth;
+
+ for (i = 0; i < set->queue_depth; ) {
+ int this_order = max_order;
+ struct page *page;
+ int to_do;
+ void *p;
+
+ while (left < order_to_size(this_order - 1) && this_order)
+ this_order--;
+
+ do {
+ page = alloc_pages_node(set->numa_node, GFP_KERNEL,
+ this_order);
+ if (page)
+ break;
+ if (!this_order--)
+ break;
+ if (order_to_size(this_order) < rq_size)
+ break;
+ } while (1);
+
+ if (!page)
+ goto fail;
+
+ page->private = this_order;
+ list_add_tail(&page->lru, &tags->page_list);
+
+ p = page_address(page);
+ entries_per_page = order_to_size(this_order) / rq_size;
+ to_do = min(entries_per_page, set->queue_depth - i);
+ left -= to_do * rq_size;
+ for (j = 0; j < to_do; j++) {
+ tags->rqs[i] = p;
+ if (set->ops->init_request) {
+ if (set->ops->init_request(set->driver_data,
+ tags->rqs[i], hctx_idx, i,
+ set->numa_node))
+ goto fail;
+ }
+
+ p += rq_size;
+ i++;
+ }
+ }
+
+ return tags;
+
+fail:
+ pr_warn("%s: failed to allocate requests\n", __func__);
+ blk_mq_free_rq_map(set, tags, hctx_idx);
+ return NULL;
+}
+
+static void blk_mq_free_bitmap(struct blk_mq_ctxmap *bitmap)
+{
+ kfree(bitmap->map);
+}
+
+static int blk_mq_alloc_bitmap(struct blk_mq_ctxmap *bitmap, int node)
+{
+ unsigned int bpw = 8, total, num_maps, i;
+
+ bitmap->bits_per_word = bpw;
+
+ num_maps = ALIGN(nr_cpu_ids, bpw) / bpw;
+ bitmap->map = kzalloc_node(num_maps * sizeof(struct blk_align_bitmap),
+ GFP_KERNEL, node);
+ if (!bitmap->map)
+ return -ENOMEM;
+
+ bitmap->map_size = num_maps;
+
+ total = nr_cpu_ids;
+ for (i = 0; i < num_maps; i++) {
+ bitmap->map[i].depth = min(total, bitmap->bits_per_word);
+ total -= bitmap->map[i].depth;
+ }
+
+ return 0;
+}
+
+static int blk_mq_hctx_cpu_offline(struct blk_mq_hw_ctx *hctx, int cpu)
{
- struct blk_mq_hw_ctx *hctx = data;
struct request_queue *q = hctx->queue;
struct blk_mq_ctx *ctx;
LIST_HEAD(tmp);
- if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
- return;
-
/*
* Move ctx entries to new CPU, if this one is going away.
*/
spin_lock(&ctx->lock);
if (!list_empty(&ctx->rq_list)) {
list_splice_init(&ctx->rq_list, &tmp);
- clear_bit(ctx->index_hw, hctx->ctx_map);
+ blk_mq_hctx_clear_pending(hctx, ctx);
}
spin_unlock(&ctx->lock);
if (list_empty(&tmp))
- return;
+ return NOTIFY_OK;
ctx = blk_mq_get_ctx(q);
spin_lock(&ctx->lock);
blk_mq_hctx_mark_pending(hctx, ctx);
spin_unlock(&ctx->lock);
- blk_mq_put_ctx(ctx);
blk_mq_run_hw_queue(hctx, true);
+ blk_mq_put_ctx(ctx);
+ return NOTIFY_OK;
}
-static int blk_mq_init_hw_commands(struct blk_mq_hw_ctx *hctx,
- int (*init)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int),
- void *data)
+static int blk_mq_hctx_cpu_online(struct blk_mq_hw_ctx *hctx, int cpu)
{
- unsigned int i;
- int ret = 0;
-
- for (i = 0; i < hctx->queue_depth; i++) {
- struct request *rq = hctx->rqs[i];
-
- ret = init(data, hctx, rq, i);
- if (ret)
- break;
- }
-
- return ret;
-}
+ struct request_queue *q = hctx->queue;
+ struct blk_mq_tag_set *set = q->tag_set;
-int blk_mq_init_commands(struct request_queue *q,
- int (*init)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int),
- void *data)
-{
- struct blk_mq_hw_ctx *hctx;
- unsigned int i;
- int ret = 0;
+ if (set->tags[hctx->queue_num])
+ return NOTIFY_OK;
- queue_for_each_hw_ctx(q, hctx, i) {
- ret = blk_mq_init_hw_commands(hctx, init, data);
- if (ret)
- break;
- }
+ set->tags[hctx->queue_num] = blk_mq_init_rq_map(set, hctx->queue_num);
+ if (!set->tags[hctx->queue_num])
+ return NOTIFY_STOP;
- return ret;
+ hctx->tags = set->tags[hctx->queue_num];
+ return NOTIFY_OK;
}
-EXPORT_SYMBOL(blk_mq_init_commands);
-static void blk_mq_free_hw_commands(struct blk_mq_hw_ctx *hctx,
- void (*free)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int),
- void *data)
+static int blk_mq_hctx_notify(void *data, unsigned long action,
+ unsigned int cpu)
{
- unsigned int i;
+ struct blk_mq_hw_ctx *hctx = data;
- for (i = 0; i < hctx->queue_depth; i++) {
- struct request *rq = hctx->rqs[i];
+ if (action == CPU_DEAD || action == CPU_DEAD_FROZEN)
+ return blk_mq_hctx_cpu_offline(hctx, cpu);
+ else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN)
+ return blk_mq_hctx_cpu_online(hctx, cpu);
- free(data, hctx, rq, i);
- }
+ return NOTIFY_OK;
}
-void blk_mq_free_commands(struct request_queue *q,
- void (*free)(void *, struct blk_mq_hw_ctx *,
- struct request *, unsigned int),
- void *data)
+static void blk_mq_exit_hw_queues(struct request_queue *q,
+ struct blk_mq_tag_set *set, int nr_queue)
{
struct blk_mq_hw_ctx *hctx;
unsigned int i;
- queue_for_each_hw_ctx(q, hctx, i)
- blk_mq_free_hw_commands(hctx, free, data);
-}
-EXPORT_SYMBOL(blk_mq_free_commands);
+ queue_for_each_hw_ctx(q, hctx, i) {
+ if (i == nr_queue)
+ break;
-static void blk_mq_free_rq_map(struct blk_mq_hw_ctx *hctx)
-{
- struct page *page;
+ if (set->ops->exit_hctx)
+ set->ops->exit_hctx(hctx, i);
- while (!list_empty(&hctx->page_list)) {
- page = list_first_entry(&hctx->page_list, struct page, lru);
- list_del_init(&page->lru);
- __free_pages(page, page->private);
+ blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier);
+ kfree(hctx->ctxs);
+ blk_mq_free_bitmap(&hctx->ctx_map);
}
- kfree(hctx->rqs);
-
- if (hctx->tags)
- blk_mq_free_tags(hctx->tags);
-}
-
-static size_t order_to_size(unsigned int order)
-{
- size_t ret = PAGE_SIZE;
-
- while (order--)
- ret *= 2;
-
- return ret;
}
-static int blk_mq_init_rq_map(struct blk_mq_hw_ctx *hctx,
- unsigned int reserved_tags, int node)
+static void blk_mq_free_hw_queues(struct request_queue *q,
+ struct blk_mq_tag_set *set)
{
- unsigned int i, j, entries_per_page, max_order = 4;
- size_t rq_size, left;
-
- INIT_LIST_HEAD(&hctx->page_list);
-
- hctx->rqs = kmalloc_node(hctx->queue_depth * sizeof(struct request *),
- GFP_KERNEL, node);
- if (!hctx->rqs)
- return -ENOMEM;
-
- /*
- * rq_size is the size of the request plus driver payload, rounded
- * to the cacheline size
- */
- rq_size = round_up(sizeof(struct request) + hctx->cmd_size,
- cache_line_size());
- left = rq_size * hctx->queue_depth;
-
- for (i = 0; i < hctx->queue_depth;) {
- int this_order = max_order;
- struct page *page;
- int to_do;
- void *p;
-
- while (left < order_to_size(this_order - 1) && this_order)
- this_order--;
-
- do {
- page = alloc_pages_node(node, GFP_KERNEL, this_order);
- if (page)
- break;
- if (!this_order--)
- break;
- if (order_to_size(this_order) < rq_size)
- break;
- } while (1);
-
- if (!page)
- break;
-
- page->private = this_order;
- list_add_tail(&page->lru, &hctx->page_list);
-
- p = page_address(page);
- entries_per_page = order_to_size(this_order) / rq_size;
- to_do = min(entries_per_page, hctx->queue_depth - i);
- left -= to_do * rq_size;
- for (j = 0; j < to_do; j++) {
- hctx->rqs[i] = p;
- blk_mq_rq_init(hctx, hctx->rqs[i]);
- p += rq_size;
- i++;
- }
- }
-
- if (i < (reserved_tags + BLK_MQ_TAG_MIN))
- goto err_rq_map;
- else if (i != hctx->queue_depth) {
- hctx->queue_depth = i;
- pr_warn("%s: queue depth set to %u because of low memory\n",
- __func__, i);
- }
+ struct blk_mq_hw_ctx *hctx;
+ unsigned int i;
- hctx->tags = blk_mq_init_tags(hctx->queue_depth, reserved_tags, node);
- if (!hctx->tags) {
-err_rq_map:
- blk_mq_free_rq_map(hctx);
- return -ENOMEM;
+ queue_for_each_hw_ctx(q, hctx, i) {
+ free_cpumask_var(hctx->cpumask);
+ kfree(hctx);
}
-
- return 0;
}
static int blk_mq_init_hw_queues(struct request_queue *q,
- struct blk_mq_reg *reg, void *driver_data)
+ struct blk_mq_tag_set *set)
{
struct blk_mq_hw_ctx *hctx;
- unsigned int i, j;
+ unsigned int i;
/*
* Initialize hardware queues
*/
queue_for_each_hw_ctx(q, hctx, i) {
- unsigned int num_maps;
int node;
node = hctx->numa_node;
if (node == NUMA_NO_NODE)
- node = hctx->numa_node = reg->numa_node;
+ node = hctx->numa_node = set->numa_node;
- INIT_DELAYED_WORK(&hctx->delayed_work, blk_mq_work_fn);
+ INIT_DELAYED_WORK(&hctx->run_work, blk_mq_run_work_fn);
+ INIT_DELAYED_WORK(&hctx->delay_work, blk_mq_delay_work_fn);
spin_lock_init(&hctx->lock);
INIT_LIST_HEAD(&hctx->dispatch);
hctx->queue = q;
hctx->queue_num = i;
- hctx->flags = reg->flags;
- hctx->queue_depth = reg->queue_depth;
- hctx->cmd_size = reg->cmd_size;
+ hctx->flags = set->flags;
+ hctx->cmd_size = set->cmd_size;
blk_mq_init_cpu_notifier(&hctx->cpu_notifier,
blk_mq_hctx_notify, hctx);
blk_mq_register_cpu_notifier(&hctx->cpu_notifier);
- if (blk_mq_init_rq_map(hctx, reg->reserved_tags, node))
- break;
+ hctx->tags = set->tags[i];
/*
* Allocate space for all possible cpus to avoid allocation in
if (!hctx->ctxs)
break;
- num_maps = ALIGN(nr_cpu_ids, BITS_PER_LONG) / BITS_PER_LONG;
- hctx->ctx_map = kzalloc_node(num_maps * sizeof(unsigned long),
- GFP_KERNEL, node);
- if (!hctx->ctx_map)
+ if (blk_mq_alloc_bitmap(&hctx->ctx_map, node))
break;
- hctx->nr_ctx_map = num_maps;
hctx->nr_ctx = 0;
- if (reg->ops->init_hctx &&
- reg->ops->init_hctx(hctx, driver_data, i))
+ if (set->ops->init_hctx &&
+ set->ops->init_hctx(hctx, set->driver_data, i))
break;
}
/*
* Init failed
*/
- queue_for_each_hw_ctx(q, hctx, j) {
- if (i == j)
- break;
-
- if (reg->ops->exit_hctx)
- reg->ops->exit_hctx(hctx, j);
-
- blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier);
- blk_mq_free_rq_map(hctx);
- kfree(hctx->ctxs);
- }
+ blk_mq_exit_hw_queues(q, set, i);
return 1;
}
__ctx->queue = q;
/* If the cpu isn't online, the cpu is mapped to first hctx */
- hctx = q->mq_ops->map_queue(q, i);
- hctx->nr_ctx++;
-
if (!cpu_online(i))
continue;
+ hctx = q->mq_ops->map_queue(q, i);
+ cpumask_set_cpu(i, hctx->cpumask);
+ hctx->nr_ctx++;
+
/*
* Set local node, IFF we have more than one hw queue. If
* not, we remain on the home node of the device
struct blk_mq_ctx *ctx;
queue_for_each_hw_ctx(q, hctx, i) {
+ cpumask_clear(hctx->cpumask);
hctx->nr_ctx = 0;
}
*/
queue_for_each_ctx(q, ctx, i) {
/* If the cpu isn't online, the cpu is mapped to first hctx */
+ if (!cpu_online(i))
+ continue;
+
hctx = q->mq_ops->map_queue(q, i);
+ cpumask_set_cpu(i, hctx->cpumask);
ctx->index_hw = hctx->nr_ctx;
hctx->ctxs[hctx->nr_ctx++] = ctx;
}
+
+ queue_for_each_hw_ctx(q, hctx, i) {
+ /*
+ * If not software queues are mapped to this hardware queue,
+ * disable it and free the request entries
+ */
+ if (!hctx->nr_ctx) {
+ struct blk_mq_tag_set *set = q->tag_set;
+
+ if (set->tags[i]) {
+ blk_mq_free_rq_map(set, set->tags[i], i);
+ set->tags[i] = NULL;
+ hctx->tags = NULL;
+ }
+ continue;
+ }
+
+ /*
+ * Initialize batch roundrobin counts
+ */
+ hctx->next_cpu = cpumask_first(hctx->cpumask);
+ hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH;
+ }
}
-struct request_queue *blk_mq_init_queue(struct blk_mq_reg *reg,
- void *driver_data)
+static void blk_mq_update_tag_set_depth(struct blk_mq_tag_set *set)
{
- struct blk_mq_hw_ctx **hctxs;
- struct blk_mq_ctx *ctx;
+ struct blk_mq_hw_ctx *hctx;
struct request_queue *q;
+ bool shared;
int i;
- if (!reg->nr_hw_queues ||
- !reg->ops->queue_rq || !reg->ops->map_queue ||
- !reg->ops->alloc_hctx || !reg->ops->free_hctx)
- return ERR_PTR(-EINVAL);
+ if (set->tag_list.next == set->tag_list.prev)
+ shared = false;
+ else
+ shared = true;
+
+ list_for_each_entry(q, &set->tag_list, tag_set_list) {
+ blk_mq_freeze_queue(q);
- if (!reg->queue_depth)
- reg->queue_depth = BLK_MQ_MAX_DEPTH;
- else if (reg->queue_depth > BLK_MQ_MAX_DEPTH) {
- pr_err("blk-mq: queuedepth too large (%u)\n", reg->queue_depth);
- reg->queue_depth = BLK_MQ_MAX_DEPTH;
+ queue_for_each_hw_ctx(q, hctx, i) {
+ if (shared)
+ hctx->flags |= BLK_MQ_F_TAG_SHARED;
+ else
+ hctx->flags &= ~BLK_MQ_F_TAG_SHARED;
+ }
+ blk_mq_unfreeze_queue(q);
}
+}
+
+static void blk_mq_del_queue_tag_set(struct request_queue *q)
+{
+ struct blk_mq_tag_set *set = q->tag_set;
+
+ blk_mq_freeze_queue(q);
+
+ mutex_lock(&set->tag_list_lock);
+ list_del_init(&q->tag_set_list);
+ blk_mq_update_tag_set_depth(set);
+ mutex_unlock(&set->tag_list_lock);
+
+ blk_mq_unfreeze_queue(q);
+}
- if (reg->queue_depth < (reg->reserved_tags + BLK_MQ_TAG_MIN))
- return ERR_PTR(-EINVAL);
+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);
+ list_add_tail(&q->tag_set_list, &set->tag_list);
+ blk_mq_update_tag_set_depth(set);
+ mutex_unlock(&set->tag_list_lock);
+}
+
+struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
+{
+ struct blk_mq_hw_ctx **hctxs;
+ struct blk_mq_ctx *ctx;
+ struct request_queue *q;
+ unsigned int *map;
+ int i;
ctx = alloc_percpu(struct blk_mq_ctx);
if (!ctx)
return ERR_PTR(-ENOMEM);
- hctxs = kmalloc_node(reg->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL,
- reg->numa_node);
+ hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL,
+ set->numa_node);
if (!hctxs)
goto err_percpu;
- for (i = 0; i < reg->nr_hw_queues; i++) {
- hctxs[i] = reg->ops->alloc_hctx(reg, i);
+ map = blk_mq_make_queue_map(set);
+ if (!map)
+ goto err_map;
+
+ for (i = 0; i < set->nr_hw_queues; i++) {
+ int node = blk_mq_hw_queue_to_node(map, i);
+
+ hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx),
+ GFP_KERNEL, node);
if (!hctxs[i])
goto err_hctxs;
- hctxs[i]->numa_node = NUMA_NO_NODE;
+ if (!zalloc_cpumask_var(&hctxs[i]->cpumask, GFP_KERNEL))
+ goto err_hctxs;
+
+ atomic_set(&hctxs[i]->nr_active, 0);
+ hctxs[i]->numa_node = node;
hctxs[i]->queue_num = i;
}
- q = blk_alloc_queue_node(GFP_KERNEL, reg->numa_node);
+ q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node);
if (!q)
goto err_hctxs;
- q->mq_map = blk_mq_make_queue_map(reg);
- if (!q->mq_map)
+ if (percpu_counter_init(&q->mq_usage_counter, 0))
goto err_map;
setup_timer(&q->timeout, blk_mq_rq_timer, (unsigned long) q);
blk_queue_rq_timeout(q, 30000);
q->nr_queues = nr_cpu_ids;
- q->nr_hw_queues = reg->nr_hw_queues;
+ q->nr_hw_queues = set->nr_hw_queues;
+ q->mq_map = map;
q->queue_ctx = ctx;
q->queue_hw_ctx = hctxs;
- q->mq_ops = reg->ops;
+ q->mq_ops = set->ops;
q->queue_flags |= QUEUE_FLAG_MQ_DEFAULT;
q->sg_reserved_size = INT_MAX;
- blk_queue_make_request(q, blk_mq_make_request);
- blk_queue_rq_timed_out(q, reg->ops->timeout);
- if (reg->timeout)
- blk_queue_rq_timeout(q, reg->timeout);
+ INIT_WORK(&q->requeue_work, blk_mq_requeue_work);
+ INIT_LIST_HEAD(&q->requeue_list);
+ spin_lock_init(&q->requeue_lock);
+
+ if (q->nr_hw_queues > 1)
+ blk_queue_make_request(q, blk_mq_make_request);
+ else
+ blk_queue_make_request(q, blk_sq_make_request);
- if (reg->ops->complete)
- blk_queue_softirq_done(q, reg->ops->complete);
+ blk_queue_rq_timed_out(q, blk_mq_rq_timed_out);
+ if (set->timeout)
+ blk_queue_rq_timeout(q, set->timeout);
+
+ /*
+ * Do this after blk_queue_make_request() overrides it...
+ */
+ q->nr_requests = set->queue_depth;
+
+ if (set->ops->complete)
+ blk_queue_softirq_done(q, set->ops->complete);
blk_mq_init_flush(q);
- blk_mq_init_cpu_queues(q, reg->nr_hw_queues);
+ blk_mq_init_cpu_queues(q, set->nr_hw_queues);
- q->flush_rq = kzalloc(round_up(sizeof(struct request) + reg->cmd_size,
- cache_line_size()), GFP_KERNEL);
+ q->flush_rq = kzalloc(round_up(sizeof(struct request) +
+ set->cmd_size, cache_line_size()),
+ GFP_KERNEL);
if (!q->flush_rq)
goto err_hw;
- if (blk_mq_init_hw_queues(q, reg, driver_data))
+ if (blk_mq_init_hw_queues(q, set))
goto err_flush_rq;
- blk_mq_map_swqueue(q);
-
mutex_lock(&all_q_mutex);
list_add_tail(&q->all_q_node, &all_q_list);
mutex_unlock(&all_q_mutex);
+ blk_mq_add_queue_tag_set(set, q);
+
+ blk_mq_map_swqueue(q);
+
return q;
err_flush_rq:
kfree(q->flush_rq);
err_hw:
- kfree(q->mq_map);
-err_map:
blk_cleanup_queue(q);
err_hctxs:
- for (i = 0; i < reg->nr_hw_queues; i++) {
+ kfree(map);
+ for (i = 0; i < set->nr_hw_queues; i++) {
if (!hctxs[i])
break;
- reg->ops->free_hctx(hctxs[i], i);
+ free_cpumask_var(hctxs[i]->cpumask);
+ kfree(hctxs[i]);
}
+err_map:
kfree(hctxs);
err_percpu:
free_percpu(ctx);
void blk_mq_free_queue(struct request_queue *q)
{
- struct blk_mq_hw_ctx *hctx;
- int i;
+ struct blk_mq_tag_set *set = q->tag_set;
- queue_for_each_hw_ctx(q, hctx, i) {
- kfree(hctx->ctx_map);
- kfree(hctx->ctxs);
- blk_mq_free_rq_map(hctx);
- blk_mq_unregister_cpu_notifier(&hctx->cpu_notifier);
- if (q->mq_ops->exit_hctx)
- q->mq_ops->exit_hctx(hctx, i);
- q->mq_ops->free_hctx(hctx, i);
- }
+ blk_mq_del_queue_tag_set(q);
+
+ blk_mq_exit_hw_queues(q, set, set->nr_hw_queues);
+ blk_mq_free_hw_queues(q, set);
+
+ percpu_counter_destroy(&q->mq_usage_counter);
free_percpu(q->queue_ctx);
kfree(q->queue_hw_ctx);
struct request_queue *q;
/*
- * Before new mapping is established, hotadded cpu might already start
- * handling requests. This doesn't break anything as we map offline
- * CPUs to first hardware queue. We will re-init queue below to get
- * optimal settings.
+ * Before new mappings are established, hotadded cpu might already
+ * start handling requests. This doesn't break anything as we map
+ * offline CPUs to first hardware queue. We will re-init the queue
+ * below to get optimal settings.
*/
if (action != CPU_DEAD && action != CPU_DEAD_FROZEN &&
action != CPU_ONLINE && action != CPU_ONLINE_FROZEN)
return NOTIFY_OK;
}
+int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
+{
+ int i;
+
+ if (!set->nr_hw_queues)
+ return -EINVAL;
+ if (!set->queue_depth || set->queue_depth > BLK_MQ_MAX_DEPTH)
+ return -EINVAL;
+ if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN)
+ return -EINVAL;
+
+ if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue)
+ return -EINVAL;
+
+
+ set->tags = kmalloc_node(set->nr_hw_queues *
+ sizeof(struct blk_mq_tags *),
+ GFP_KERNEL, set->numa_node);
+ if (!set->tags)
+ goto out;
+
+ for (i = 0; i < set->nr_hw_queues; i++) {
+ set->tags[i] = blk_mq_init_rq_map(set, i);
+ if (!set->tags[i])
+ goto out_unwind;
+ }
+
+ mutex_init(&set->tag_list_lock);
+ INIT_LIST_HEAD(&set->tag_list);
+
+ return 0;
+
+out_unwind:
+ while (--i >= 0)
+ blk_mq_free_rq_map(set, set->tags[i], i);
+out:
+ return -ENOMEM;
+}
+EXPORT_SYMBOL(blk_mq_alloc_tag_set);
+
+void blk_mq_free_tag_set(struct blk_mq_tag_set *set)
+{
+ int i;
+
+ for (i = 0; i < set->nr_hw_queues; i++) {
+ if (set->tags[i])
+ blk_mq_free_rq_map(set, set->tags[i], i);
+ }
+
+ kfree(set->tags);
+}
+EXPORT_SYMBOL(blk_mq_free_tag_set);
+
+int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr)
+{
+ struct blk_mq_tag_set *set = q->tag_set;
+ struct blk_mq_hw_ctx *hctx;
+ int i, ret;
+
+ if (!set || nr > set->queue_depth)
+ return -EINVAL;
+
+ ret = 0;
+ queue_for_each_hw_ctx(q, hctx, i) {
+ ret = blk_mq_tag_update_depth(hctx->tags, nr);
+ if (ret)
+ break;
+ }
+
+ if (!ret)
+ q->nr_requests = nr;
+
+ return ret;
+}
+
void blk_mq_disable_hotplug(void)
{
mutex_lock(&all_q_mutex);
projects / mirror_ubuntu-artful-kernel.git / blobdiff