1491 lines
34 KiB
C
1491 lines
34 KiB
C
#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/backing-dev.h>
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#include <linux/bio.h>
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#include <linux/blkdev.h>
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/slab.h>
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#include <linux/workqueue.h>
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#include <linux/smp.h>
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#include <linux/llist.h>
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#include <linux/list_sort.h>
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#include <linux/cpu.h>
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#include <linux/cache.h>
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#include <linux/sched/sysctl.h>
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#include <linux/delay.h>
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#include <trace/events/block.h>
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#include <linux/blk-mq.h>
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#include "blk.h"
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#include "blk-mq.h"
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#include "blk-mq-tag.h"
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static DEFINE_MUTEX(all_q_mutex);
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static LIST_HEAD(all_q_list);
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static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx);
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DEFINE_PER_CPU(struct llist_head, ipi_lists);
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static struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
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unsigned int cpu)
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{
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return per_cpu_ptr(q->queue_ctx, cpu);
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}
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/*
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* This assumes per-cpu software queueing queues. They could be per-node
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* as well, for instance. For now this is hardcoded as-is. Note that we don't
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* care about preemption, since we know the ctx's are persistent. This does
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* mean that we can't rely on ctx always matching the currently running CPU.
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*/
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static struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
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{
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return __blk_mq_get_ctx(q, get_cpu());
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}
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static void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
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{
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put_cpu();
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}
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/*
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* Check if any of the ctx's have pending work in this hardware queue
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*/
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static bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx)
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{
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unsigned int i;
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for (i = 0; i < hctx->nr_ctx_map; i++)
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if (hctx->ctx_map[i])
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return true;
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return false;
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}
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/*
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* Mark this ctx as having pending work in this hardware queue
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*/
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static void blk_mq_hctx_mark_pending(struct blk_mq_hw_ctx *hctx,
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struct blk_mq_ctx *ctx)
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{
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if (!test_bit(ctx->index_hw, hctx->ctx_map))
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set_bit(ctx->index_hw, hctx->ctx_map);
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}
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static struct request *blk_mq_alloc_rq(struct blk_mq_hw_ctx *hctx, gfp_t gfp,
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bool reserved)
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{
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struct request *rq;
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unsigned int tag;
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tag = blk_mq_get_tag(hctx->tags, gfp, reserved);
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if (tag != BLK_MQ_TAG_FAIL) {
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rq = hctx->rqs[tag];
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rq->tag = tag;
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return rq;
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}
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return NULL;
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}
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static int blk_mq_queue_enter(struct request_queue *q)
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{
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int ret;
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__percpu_counter_add(&q->mq_usage_counter, 1, 1000000);
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smp_wmb();
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/* we have problems to freeze the queue if it's initializing */
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if (!blk_queue_bypass(q) || !blk_queue_init_done(q))
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return 0;
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__percpu_counter_add(&q->mq_usage_counter, -1, 1000000);
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spin_lock_irq(q->queue_lock);
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ret = wait_event_interruptible_lock_irq(q->mq_freeze_wq,
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!blk_queue_bypass(q), *q->queue_lock);
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/* inc usage with lock hold to avoid freeze_queue runs here */
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if (!ret)
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__percpu_counter_add(&q->mq_usage_counter, 1, 1000000);
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spin_unlock_irq(q->queue_lock);
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return ret;
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}
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static void blk_mq_queue_exit(struct request_queue *q)
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{
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__percpu_counter_add(&q->mq_usage_counter, -1, 1000000);
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}
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/*
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* Guarantee no request is in use, so we can change any data structure of
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* the queue afterward.
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*/
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static void blk_mq_freeze_queue(struct request_queue *q)
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{
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bool drain;
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spin_lock_irq(q->queue_lock);
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drain = !q->bypass_depth++;
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queue_flag_set(QUEUE_FLAG_BYPASS, q);
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spin_unlock_irq(q->queue_lock);
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if (!drain)
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return;
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while (true) {
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s64 count;
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spin_lock_irq(q->queue_lock);
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count = percpu_counter_sum(&q->mq_usage_counter);
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spin_unlock_irq(q->queue_lock);
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if (count == 0)
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break;
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blk_mq_run_queues(q, false);
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msleep(10);
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}
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}
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static void blk_mq_unfreeze_queue(struct request_queue *q)
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{
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bool wake = false;
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spin_lock_irq(q->queue_lock);
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if (!--q->bypass_depth) {
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queue_flag_clear(QUEUE_FLAG_BYPASS, q);
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wake = true;
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}
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WARN_ON_ONCE(q->bypass_depth < 0);
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spin_unlock_irq(q->queue_lock);
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if (wake)
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wake_up_all(&q->mq_freeze_wq);
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}
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bool blk_mq_can_queue(struct blk_mq_hw_ctx *hctx)
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{
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return blk_mq_has_free_tags(hctx->tags);
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}
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EXPORT_SYMBOL(blk_mq_can_queue);
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static void blk_mq_rq_ctx_init(struct blk_mq_ctx *ctx, struct request *rq,
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unsigned int rw_flags)
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{
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rq->mq_ctx = ctx;
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rq->cmd_flags = rw_flags;
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ctx->rq_dispatched[rw_is_sync(rw_flags)]++;
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}
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static struct request *__blk_mq_alloc_request(struct blk_mq_hw_ctx *hctx,
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gfp_t gfp, bool reserved)
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{
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return blk_mq_alloc_rq(hctx, gfp, reserved);
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}
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static struct request *blk_mq_alloc_request_pinned(struct request_queue *q,
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int rw, gfp_t gfp,
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bool reserved)
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{
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struct request *rq;
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do {
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struct blk_mq_ctx *ctx = blk_mq_get_ctx(q);
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struct blk_mq_hw_ctx *hctx = q->mq_ops->map_queue(q, ctx->cpu);
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rq = __blk_mq_alloc_request(hctx, gfp & ~__GFP_WAIT, reserved);
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if (rq) {
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blk_mq_rq_ctx_init(ctx, rq, rw);
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break;
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} else if (!(gfp & __GFP_WAIT))
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break;
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blk_mq_put_ctx(ctx);
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__blk_mq_run_hw_queue(hctx);
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blk_mq_wait_for_tags(hctx->tags);
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} while (1);
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return rq;
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}
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struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp)
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{
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struct request *rq;
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if (blk_mq_queue_enter(q))
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return NULL;
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rq = blk_mq_alloc_request_pinned(q, rw, gfp, false);
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blk_mq_put_ctx(rq->mq_ctx);
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return rq;
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}
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struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw,
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gfp_t gfp)
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{
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struct request *rq;
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if (blk_mq_queue_enter(q))
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return NULL;
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rq = blk_mq_alloc_request_pinned(q, rw, gfp, true);
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blk_mq_put_ctx(rq->mq_ctx);
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return rq;
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}
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EXPORT_SYMBOL(blk_mq_alloc_reserved_request);
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/*
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* Re-init and set pdu, if we have it
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*/
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static void blk_mq_rq_init(struct blk_mq_hw_ctx *hctx, struct request *rq)
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{
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blk_rq_init(hctx->queue, rq);
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if (hctx->cmd_size)
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rq->special = blk_mq_rq_to_pdu(rq);
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}
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static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx,
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struct blk_mq_ctx *ctx, struct request *rq)
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{
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const int tag = rq->tag;
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struct request_queue *q = rq->q;
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blk_mq_rq_init(hctx, rq);
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blk_mq_put_tag(hctx->tags, tag);
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blk_mq_queue_exit(q);
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}
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void blk_mq_free_request(struct request *rq)
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{
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struct blk_mq_ctx *ctx = rq->mq_ctx;
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struct blk_mq_hw_ctx *hctx;
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struct request_queue *q = rq->q;
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ctx->rq_completed[rq_is_sync(rq)]++;
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hctx = q->mq_ops->map_queue(q, ctx->cpu);
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__blk_mq_free_request(hctx, ctx, rq);
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}
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static void blk_mq_bio_endio(struct request *rq, struct bio *bio, int error)
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{
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if (error)
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clear_bit(BIO_UPTODATE, &bio->bi_flags);
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else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
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error = -EIO;
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if (unlikely(rq->cmd_flags & REQ_QUIET))
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set_bit(BIO_QUIET, &bio->bi_flags);
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/* don't actually finish bio if it's part of flush sequence */
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if (!(rq->cmd_flags & REQ_FLUSH_SEQ))
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bio_endio(bio, error);
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}
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void blk_mq_complete_request(struct request *rq, int error)
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{
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struct bio *bio = rq->bio;
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unsigned int bytes = 0;
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trace_block_rq_complete(rq->q, rq);
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while (bio) {
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struct bio *next = bio->bi_next;
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bio->bi_next = NULL;
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bytes += bio->bi_size;
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blk_mq_bio_endio(rq, bio, error);
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bio = next;
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}
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blk_account_io_completion(rq, bytes);
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if (rq->end_io)
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rq->end_io(rq, error);
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else
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blk_mq_free_request(rq);
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blk_account_io_done(rq);
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}
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void __blk_mq_end_io(struct request *rq, int error)
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{
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if (!blk_mark_rq_complete(rq))
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blk_mq_complete_request(rq, error);
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}
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#if defined(CONFIG_SMP) && defined(CONFIG_USE_GENERIC_SMP_HELPERS)
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/*
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* Called with interrupts disabled.
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*/
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static void ipi_end_io(void *data)
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{
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struct llist_head *list = &per_cpu(ipi_lists, smp_processor_id());
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struct llist_node *entry, *next;
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struct request *rq;
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entry = llist_del_all(list);
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while (entry) {
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next = entry->next;
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rq = llist_entry(entry, struct request, ll_list);
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__blk_mq_end_io(rq, rq->errors);
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entry = next;
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}
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}
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static int ipi_remote_cpu(struct blk_mq_ctx *ctx, const int cpu,
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struct request *rq, const int error)
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{
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struct call_single_data *data = &rq->csd;
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rq->errors = error;
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rq->ll_list.next = NULL;
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/*
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* If the list is non-empty, an existing IPI must already
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* be "in flight". If that is the case, we need not schedule
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* a new one.
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*/
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if (llist_add(&rq->ll_list, &per_cpu(ipi_lists, ctx->cpu))) {
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data->func = ipi_end_io;
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data->flags = 0;
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__smp_call_function_single(ctx->cpu, data, 0);
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}
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return true;
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}
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#else /* CONFIG_SMP && CONFIG_USE_GENERIC_SMP_HELPERS */
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static int ipi_remote_cpu(struct blk_mq_ctx *ctx, const int cpu,
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struct request *rq, const int error)
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{
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return false;
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}
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#endif
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/*
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* End IO on this request on a multiqueue enabled driver. We'll either do
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* it directly inline, or punt to a local IPI handler on the matching
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* remote CPU.
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*/
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void blk_mq_end_io(struct request *rq, int error)
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{
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struct blk_mq_ctx *ctx = rq->mq_ctx;
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int cpu;
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if (!ctx->ipi_redirect)
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return __blk_mq_end_io(rq, error);
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cpu = get_cpu();
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if (cpu == ctx->cpu || !cpu_online(ctx->cpu) ||
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!ipi_remote_cpu(ctx, cpu, rq, error))
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__blk_mq_end_io(rq, error);
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put_cpu();
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}
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EXPORT_SYMBOL(blk_mq_end_io);
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static void blk_mq_start_request(struct request *rq)
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{
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struct request_queue *q = rq->q;
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trace_block_rq_issue(q, rq);
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/*
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* Just mark start time and set the started bit. Due to memory
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* ordering, we know we'll see the correct deadline as long as
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* REQ_ATOMIC_STARTED is seen.
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*/
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rq->deadline = jiffies + q->rq_timeout;
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set_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
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}
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static void blk_mq_requeue_request(struct request *rq)
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{
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struct request_queue *q = rq->q;
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trace_block_rq_requeue(q, rq);
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clear_bit(REQ_ATOM_STARTED, &rq->atomic_flags);
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}
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struct blk_mq_timeout_data {
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struct blk_mq_hw_ctx *hctx;
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unsigned long *next;
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unsigned int *next_set;
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};
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static void blk_mq_timeout_check(void *__data, unsigned long *free_tags)
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{
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struct blk_mq_timeout_data *data = __data;
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struct blk_mq_hw_ctx *hctx = data->hctx;
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unsigned int tag;
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/* It may not be in flight yet (this is where
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* the REQ_ATOMIC_STARTED flag comes in). The requests are
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* statically allocated, so we know it's always safe to access the
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* memory associated with a bit offset into ->rqs[].
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*/
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tag = 0;
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do {
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struct request *rq;
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tag = find_next_zero_bit(free_tags, hctx->queue_depth, tag);
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if (tag >= hctx->queue_depth)
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break;
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rq = hctx->rqs[tag++];
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if (!test_bit(REQ_ATOM_STARTED, &rq->atomic_flags))
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continue;
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blk_rq_check_expired(rq, data->next, data->next_set);
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} while (1);
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}
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static void blk_mq_hw_ctx_check_timeout(struct blk_mq_hw_ctx *hctx,
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unsigned long *next,
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unsigned int *next_set)
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{
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struct blk_mq_timeout_data data = {
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.hctx = hctx,
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.next = next,
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.next_set = next_set,
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};
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/*
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* Ask the tagging code to iterate busy requests, so we can
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* check them for timeout.
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*/
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blk_mq_tag_busy_iter(hctx->tags, blk_mq_timeout_check, &data);
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}
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static void blk_mq_rq_timer(unsigned long data)
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{
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struct request_queue *q = (struct request_queue *) data;
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struct blk_mq_hw_ctx *hctx;
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unsigned long next = 0;
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int i, next_set = 0;
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queue_for_each_hw_ctx(q, hctx, i)
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blk_mq_hw_ctx_check_timeout(hctx, &next, &next_set);
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if (next_set)
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mod_timer(&q->timeout, round_jiffies_up(next));
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}
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/*
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* Reverse check our software queue for entries that we could potentially
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* merge with. Currently includes a hand-wavy stop count of 8, to not spend
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* too much time checking for merges.
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*/
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static bool blk_mq_attempt_merge(struct request_queue *q,
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struct blk_mq_ctx *ctx, struct bio *bio)
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{
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struct request *rq;
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int checked = 8;
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list_for_each_entry_reverse(rq, &ctx->rq_list, queuelist) {
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int el_ret;
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if (!checked--)
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break;
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if (!blk_rq_merge_ok(rq, bio))
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continue;
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el_ret = blk_try_merge(rq, bio);
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if (el_ret == ELEVATOR_BACK_MERGE) {
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if (bio_attempt_back_merge(q, rq, bio)) {
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ctx->rq_merged++;
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return true;
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}
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break;
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} else if (el_ret == ELEVATOR_FRONT_MERGE) {
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if (bio_attempt_front_merge(q, rq, bio)) {
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ctx->rq_merged++;
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return true;
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}
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break;
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}
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}
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return false;
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}
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|
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void blk_mq_add_timer(struct request *rq)
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{
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__blk_add_timer(rq, NULL);
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}
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|
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/*
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* Run this hardware queue, pulling any software queues mapped to it in.
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* Note that this function currently has various problems around ordering
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* of IO. In particular, we'd like FIFO behaviour on handling existing
|
|
* items on the hctx->dispatch list. Ignore that for now.
|
|
*/
|
|
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;
|
|
|
|
if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->flags)))
|
|
return;
|
|
|
|
hctx->run++;
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
/*
|
|
* If we have previous entries on our dispatch list, grab them
|
|
* and stuff them at the front for more fair dispatch.
|
|
*/
|
|
if (!list_empty_careful(&hctx->dispatch)) {
|
|
spin_lock(&hctx->lock);
|
|
if (!list_empty(&hctx->dispatch))
|
|
list_splice_init(&hctx->dispatch, &rq_list);
|
|
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.
|
|
*/
|
|
while (!list_empty(&rq_list)) {
|
|
int ret;
|
|
|
|
rq = list_first_entry(&rq_list, struct request, queuelist);
|
|
list_del_init(&rq->queuelist);
|
|
blk_mq_start_request(rq);
|
|
|
|
/*
|
|
* Last request in the series. Flag it as such, this
|
|
* enables drivers to know when IO should be kicked off,
|
|
* if they don't do it on a per-request basis.
|
|
*
|
|
* Note: the flag isn't the only condition drivers
|
|
* should do kick off. If drive is busy, the last
|
|
* request might not have the bit set.
|
|
*/
|
|
if (list_empty(&rq_list))
|
|
rq->cmd_flags |= REQ_END;
|
|
|
|
ret = q->mq_ops->queue_rq(hctx, rq);
|
|
switch (ret) {
|
|
case BLK_MQ_RQ_QUEUE_OK:
|
|
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);
|
|
break;
|
|
default:
|
|
pr_err("blk-mq: bad return on queue: %d\n", ret);
|
|
rq->errors = -EIO;
|
|
case BLK_MQ_RQ_QUEUE_ERROR:
|
|
blk_mq_end_io(rq, rq->errors);
|
|
break;
|
|
}
|
|
|
|
if (ret == BLK_MQ_RQ_QUEUE_BUSY)
|
|
break;
|
|
}
|
|
|
|
if (!queued)
|
|
hctx->dispatched[0]++;
|
|
else if (queued < (1 << (BLK_MQ_MAX_DISPATCH_ORDER - 1)))
|
|
hctx->dispatched[ilog2(queued) + 1]++;
|
|
|
|
/*
|
|
* Any items that need requeuing? Stuff them into hctx->dispatch,
|
|
* that is where we will continue on next queue run.
|
|
*/
|
|
if (!list_empty(&rq_list)) {
|
|
spin_lock(&hctx->lock);
|
|
list_splice(&rq_list, &hctx->dispatch);
|
|
spin_unlock(&hctx->lock);
|
|
}
|
|
}
|
|
|
|
void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
|
|
{
|
|
if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->flags)))
|
|
return;
|
|
|
|
if (!async)
|
|
__blk_mq_run_hw_queue(hctx);
|
|
else {
|
|
struct request_queue *q = hctx->queue;
|
|
|
|
kblockd_schedule_delayed_work(q, &hctx->delayed_work, 0);
|
|
}
|
|
}
|
|
|
|
void blk_mq_run_queues(struct request_queue *q, bool async)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
int i;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i) {
|
|
if ((!blk_mq_hctx_has_pending(hctx) &&
|
|
list_empty_careful(&hctx->dispatch)) ||
|
|
test_bit(BLK_MQ_S_STOPPED, &hctx->flags))
|
|
continue;
|
|
|
|
blk_mq_run_hw_queue(hctx, async);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_run_queues);
|
|
|
|
void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx)
|
|
{
|
|
cancel_delayed_work(&hctx->delayed_work);
|
|
set_bit(BLK_MQ_S_STOPPED, &hctx->state);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_stop_hw_queue);
|
|
|
|
void blk_mq_stop_hw_queues(struct request_queue *q)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
int i;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i)
|
|
blk_mq_stop_hw_queue(hctx);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_stop_hw_queues);
|
|
|
|
void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx)
|
|
{
|
|
clear_bit(BLK_MQ_S_STOPPED, &hctx->state);
|
|
__blk_mq_run_hw_queue(hctx);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_start_hw_queue);
|
|
|
|
void blk_mq_start_stopped_hw_queues(struct request_queue *q)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
int i;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i) {
|
|
if (!test_bit(BLK_MQ_S_STOPPED, &hctx->state))
|
|
continue;
|
|
|
|
clear_bit(BLK_MQ_S_STOPPED, &hctx->state);
|
|
blk_mq_run_hw_queue(hctx, true);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues);
|
|
|
|
static void blk_mq_work_fn(struct work_struct *work)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
|
|
hctx = container_of(work, struct blk_mq_hw_ctx, delayed_work.work);
|
|
__blk_mq_run_hw_queue(hctx);
|
|
}
|
|
|
|
static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx,
|
|
struct request *rq)
|
|
{
|
|
struct blk_mq_ctx *ctx = rq->mq_ctx;
|
|
|
|
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);
|
|
}
|
|
|
|
void blk_mq_insert_request(struct request_queue *q, struct request *rq,
|
|
bool run_queue)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
struct blk_mq_ctx *ctx, *current_ctx;
|
|
|
|
ctx = rq->mq_ctx;
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
|
|
if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA)) {
|
|
blk_insert_flush(rq);
|
|
} else {
|
|
current_ctx = blk_mq_get_ctx(q);
|
|
|
|
if (!cpu_online(ctx->cpu)) {
|
|
ctx = current_ctx;
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
rq->mq_ctx = ctx;
|
|
}
|
|
spin_lock(&ctx->lock);
|
|
__blk_mq_insert_request(hctx, rq);
|
|
spin_unlock(&ctx->lock);
|
|
|
|
blk_mq_put_ctx(current_ctx);
|
|
}
|
|
|
|
if (run_queue)
|
|
__blk_mq_run_hw_queue(hctx);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_insert_request);
|
|
|
|
/*
|
|
* This is a special version of blk_mq_insert_request to bypass FLUSH request
|
|
* check. Should only be used internally.
|
|
*/
|
|
void blk_mq_run_request(struct request *rq, bool run_queue, bool async)
|
|
{
|
|
struct request_queue *q = rq->q;
|
|
struct blk_mq_hw_ctx *hctx;
|
|
struct blk_mq_ctx *ctx, *current_ctx;
|
|
|
|
current_ctx = blk_mq_get_ctx(q);
|
|
|
|
ctx = rq->mq_ctx;
|
|
if (!cpu_online(ctx->cpu)) {
|
|
ctx = current_ctx;
|
|
rq->mq_ctx = ctx;
|
|
}
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
|
|
/* ctx->cpu might be offline */
|
|
spin_lock(&ctx->lock);
|
|
__blk_mq_insert_request(hctx, rq);
|
|
spin_unlock(&ctx->lock);
|
|
|
|
blk_mq_put_ctx(current_ctx);
|
|
|
|
if (run_queue)
|
|
blk_mq_run_hw_queue(hctx, async);
|
|
}
|
|
|
|
static void blk_mq_insert_requests(struct request_queue *q,
|
|
struct blk_mq_ctx *ctx,
|
|
struct list_head *list,
|
|
int depth,
|
|
bool from_schedule)
|
|
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
struct blk_mq_ctx *current_ctx;
|
|
|
|
trace_block_unplug(q, depth, !from_schedule);
|
|
|
|
current_ctx = blk_mq_get_ctx(q);
|
|
|
|
if (!cpu_online(ctx->cpu))
|
|
ctx = current_ctx;
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
|
|
/*
|
|
* preemption doesn't flush plug list, so it's possible ctx->cpu is
|
|
* offline now
|
|
*/
|
|
spin_lock(&ctx->lock);
|
|
while (!list_empty(list)) {
|
|
struct request *rq;
|
|
|
|
rq = list_first_entry(list, struct request, queuelist);
|
|
list_del_init(&rq->queuelist);
|
|
rq->mq_ctx = ctx;
|
|
__blk_mq_insert_request(hctx, rq);
|
|
}
|
|
spin_unlock(&ctx->lock);
|
|
|
|
blk_mq_put_ctx(current_ctx);
|
|
|
|
blk_mq_run_hw_queue(hctx, from_schedule);
|
|
}
|
|
|
|
static int plug_ctx_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)));
|
|
}
|
|
|
|
void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule)
|
|
{
|
|
struct blk_mq_ctx *this_ctx;
|
|
struct request_queue *this_q;
|
|
struct request *rq;
|
|
LIST_HEAD(list);
|
|
LIST_HEAD(ctx_list);
|
|
unsigned int depth;
|
|
|
|
list_splice_init(&plug->mq_list, &list);
|
|
|
|
list_sort(NULL, &list, plug_ctx_cmp);
|
|
|
|
this_q = NULL;
|
|
this_ctx = NULL;
|
|
depth = 0;
|
|
|
|
while (!list_empty(&list)) {
|
|
rq = list_entry_rq(list.next);
|
|
list_del_init(&rq->queuelist);
|
|
BUG_ON(!rq->q);
|
|
if (rq->mq_ctx != this_ctx) {
|
|
if (this_ctx) {
|
|
blk_mq_insert_requests(this_q, this_ctx,
|
|
&ctx_list, depth,
|
|
from_schedule);
|
|
}
|
|
|
|
this_ctx = rq->mq_ctx;
|
|
this_q = rq->q;
|
|
depth = 0;
|
|
}
|
|
|
|
depth++;
|
|
list_add_tail(&rq->queuelist, &ctx_list);
|
|
}
|
|
|
|
/*
|
|
* If 'this_ctx' is set, we know we have entries to complete
|
|
* on 'ctx_list'. Do those.
|
|
*/
|
|
if (this_ctx) {
|
|
blk_mq_insert_requests(this_q, this_ctx, &ctx_list, depth,
|
|
from_schedule);
|
|
}
|
|
}
|
|
|
|
static void blk_mq_bio_to_request(struct request *rq, struct bio *bio)
|
|
{
|
|
init_request_from_bio(rq, bio);
|
|
blk_account_io_start(rq, 1);
|
|
}
|
|
|
|
static void blk_mq_make_request(struct request_queue *q, 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);
|
|
|
|
blk_queue_bounce(q, &bio);
|
|
|
|
if (use_plug && blk_attempt_plug_merge(q, bio, &request_count))
|
|
return;
|
|
|
|
if (blk_mq_queue_enter(q)) {
|
|
bio_endio(bio, -EIO);
|
|
return;
|
|
}
|
|
|
|
ctx = blk_mq_get_ctx(q);
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
|
|
trace_block_getrq(q, bio, rw);
|
|
rq = __blk_mq_alloc_request(hctx, GFP_ATOMIC, false);
|
|
if (likely(rq))
|
|
blk_mq_rq_ctx_init(ctx, rq, rw);
|
|
else {
|
|
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;
|
|
hctx = q->mq_ops->map_queue(q, ctx->cpu);
|
|
}
|
|
|
|
hctx->queued++;
|
|
|
|
if (unlikely(is_flush_fua)) {
|
|
blk_mq_bio_to_request(rq, bio);
|
|
blk_mq_put_ctx(ctx);
|
|
blk_insert_flush(rq);
|
|
goto run_queue;
|
|
}
|
|
|
|
/*
|
|
* A task plug currently exists. Since this is completely lockless,
|
|
* utilize that to temporarily store requests until the task is
|
|
* either done or scheduled away.
|
|
*/
|
|
if (use_plug) {
|
|
struct blk_plug *plug = current->plug;
|
|
|
|
if (plug) {
|
|
blk_mq_bio_to_request(rq, bio);
|
|
if (list_empty(&plug->list))
|
|
trace_block_plug(q);
|
|
else if (request_count >= BLK_MAX_REQUEST_COUNT) {
|
|
blk_flush_plug_list(plug, false);
|
|
trace_block_plug(q);
|
|
}
|
|
list_add_tail(&rq->queuelist, &plug->mq_list);
|
|
blk_mq_put_ctx(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);
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* Default mapping to a software queue, since we use one per CPU.
|
|
*/
|
|
struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu)
|
|
{
|
|
return q->queue_hw_ctx[q->mq_map[cpu]];
|
|
}
|
|
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)
|
|
{
|
|
return kmalloc_node(sizeof(struct blk_mq_hw_ctx),
|
|
GFP_KERNEL | __GFP_ZERO, reg->numa_node);
|
|
}
|
|
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)
|
|
{
|
|
kfree(hctx);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_free_single_hw_queue);
|
|
|
|
static void blk_mq_hctx_notify(void *data, unsigned long action,
|
|
unsigned int cpu)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx = data;
|
|
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.
|
|
*/
|
|
ctx = __blk_mq_get_ctx(hctx->queue, cpu);
|
|
|
|
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);
|
|
}
|
|
spin_unlock(&ctx->lock);
|
|
|
|
if (list_empty(&tmp))
|
|
return;
|
|
|
|
ctx = blk_mq_get_ctx(hctx->queue);
|
|
spin_lock(&ctx->lock);
|
|
|
|
while (!list_empty(&tmp)) {
|
|
struct request *rq;
|
|
|
|
rq = list_first_entry(&tmp, struct request, queuelist);
|
|
rq->mq_ctx = ctx;
|
|
list_move_tail(&rq->queuelist, &ctx->rq_list);
|
|
}
|
|
|
|
blk_mq_hctx_mark_pending(hctx, ctx);
|
|
|
|
spin_unlock(&ctx->lock);
|
|
blk_mq_put_ctx(ctx);
|
|
}
|
|
|
|
static void blk_mq_init_hw_commands(struct blk_mq_hw_ctx *hctx,
|
|
void (*init)(void *, struct blk_mq_hw_ctx *,
|
|
struct request *, unsigned int),
|
|
void *data)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < hctx->queue_depth; i++) {
|
|
struct request *rq = hctx->rqs[i];
|
|
|
|
init(data, hctx, rq, i);
|
|
}
|
|
}
|
|
|
|
void blk_mq_init_commands(struct request_queue *q,
|
|
void (*init)(void *, struct blk_mq_hw_ctx *,
|
|
struct request *, unsigned int),
|
|
void *data)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
unsigned int i;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i)
|
|
blk_mq_init_hw_commands(hctx, init, data);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_init_commands);
|
|
|
|
static void blk_mq_free_rq_map(struct blk_mq_hw_ctx *hctx)
|
|
{
|
|
struct page *page;
|
|
|
|
while (!list_empty(&hctx->page_list)) {
|
|
page = list_first_entry(&hctx->page_list, struct page, list);
|
|
list_del_init(&page->list);
|
|
__free_pages(page, page->private);
|
|
}
|
|
|
|
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)
|
|
{
|
|
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->list, &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);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int blk_mq_init_hw_queues(struct request_queue *q,
|
|
struct blk_mq_reg *reg, void *driver_data)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
unsigned int i, j;
|
|
|
|
/*
|
|
* 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;
|
|
|
|
INIT_DELAYED_WORK(&hctx->delayed_work, blk_mq_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;
|
|
|
|
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;
|
|
|
|
/*
|
|
* Allocate space for all possible cpus to avoid allocation in
|
|
* runtime
|
|
*/
|
|
hctx->ctxs = kmalloc_node(nr_cpu_ids * sizeof(void *),
|
|
GFP_KERNEL, node);
|
|
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)
|
|
break;
|
|
|
|
hctx->nr_ctx_map = num_maps;
|
|
hctx->nr_ctx = 0;
|
|
|
|
if (reg->ops->init_hctx &&
|
|
reg->ops->init_hctx(hctx, driver_data, i))
|
|
break;
|
|
}
|
|
|
|
if (i == q->nr_hw_queues)
|
|
return 0;
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
static void blk_mq_init_cpu_queues(struct request_queue *q,
|
|
unsigned int nr_hw_queues)
|
|
{
|
|
unsigned int i;
|
|
|
|
for_each_possible_cpu(i) {
|
|
struct blk_mq_ctx *__ctx = per_cpu_ptr(q->queue_ctx, i);
|
|
struct blk_mq_hw_ctx *hctx;
|
|
|
|
memset(__ctx, 0, sizeof(*__ctx));
|
|
__ctx->cpu = i;
|
|
spin_lock_init(&__ctx->lock);
|
|
INIT_LIST_HEAD(&__ctx->rq_list);
|
|
__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;
|
|
|
|
/*
|
|
* Set local node, IFF we have more than one hw queue. If
|
|
* not, we remain on the home node of the device
|
|
*/
|
|
if (nr_hw_queues > 1 && hctx->numa_node == NUMA_NO_NODE)
|
|
hctx->numa_node = cpu_to_node(i);
|
|
}
|
|
}
|
|
|
|
static void blk_mq_map_swqueue(struct request_queue *q)
|
|
{
|
|
unsigned int i;
|
|
struct blk_mq_hw_ctx *hctx;
|
|
struct blk_mq_ctx *ctx;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i) {
|
|
hctx->nr_ctx = 0;
|
|
}
|
|
|
|
/*
|
|
* Map software to hardware queues
|
|
*/
|
|
queue_for_each_ctx(q, ctx, i) {
|
|
/* If the cpu isn't online, the cpu is mapped to first hctx */
|
|
hctx = q->mq_ops->map_queue(q, i);
|
|
ctx->index_hw = hctx->nr_ctx;
|
|
hctx->ctxs[hctx->nr_ctx++] = ctx;
|
|
}
|
|
}
|
|
|
|
struct request_queue *blk_mq_init_queue(struct blk_mq_reg *reg,
|
|
void *driver_data)
|
|
{
|
|
struct blk_mq_hw_ctx **hctxs;
|
|
struct blk_mq_ctx *ctx;
|
|
struct request_queue *q;
|
|
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 (!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;
|
|
}
|
|
|
|
if (reg->queue_depth < (reg->reserved_tags + BLK_MQ_TAG_MIN))
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
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);
|
|
|
|
if (!hctxs)
|
|
goto err_percpu;
|
|
|
|
for (i = 0; i < reg->nr_hw_queues; i++) {
|
|
hctxs[i] = reg->ops->alloc_hctx(reg, i);
|
|
if (!hctxs[i])
|
|
goto err_hctxs;
|
|
|
|
hctxs[i]->numa_node = NUMA_NO_NODE;
|
|
hctxs[i]->queue_num = i;
|
|
}
|
|
|
|
q = blk_alloc_queue_node(GFP_KERNEL, reg->numa_node);
|
|
if (!q)
|
|
goto err_hctxs;
|
|
|
|
q->mq_map = blk_mq_make_queue_map(reg);
|
|
if (!q->mq_map)
|
|
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->queue_ctx = ctx;
|
|
q->queue_hw_ctx = hctxs;
|
|
|
|
q->mq_ops = reg->ops;
|
|
|
|
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);
|
|
|
|
blk_mq_init_flush(q);
|
|
blk_mq_init_cpu_queues(q, reg->nr_hw_queues);
|
|
|
|
if (blk_mq_init_hw_queues(q, reg, driver_data))
|
|
goto err_hw;
|
|
|
|
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);
|
|
|
|
return q;
|
|
err_hw:
|
|
kfree(q->mq_map);
|
|
err_map:
|
|
blk_cleanup_queue(q);
|
|
err_hctxs:
|
|
for (i = 0; i < reg->nr_hw_queues; i++) {
|
|
if (!hctxs[i])
|
|
break;
|
|
reg->ops->free_hctx(hctxs[i], i);
|
|
}
|
|
kfree(hctxs);
|
|
err_percpu:
|
|
free_percpu(ctx);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_init_queue);
|
|
|
|
void blk_mq_free_queue(struct request_queue *q)
|
|
{
|
|
struct blk_mq_hw_ctx *hctx;
|
|
int i;
|
|
|
|
queue_for_each_hw_ctx(q, hctx, i) {
|
|
cancel_delayed_work_sync(&hctx->delayed_work);
|
|
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);
|
|
}
|
|
|
|
free_percpu(q->queue_ctx);
|
|
kfree(q->queue_hw_ctx);
|
|
kfree(q->mq_map);
|
|
|
|
q->queue_ctx = NULL;
|
|
q->queue_hw_ctx = NULL;
|
|
q->mq_map = NULL;
|
|
|
|
mutex_lock(&all_q_mutex);
|
|
list_del_init(&q->all_q_node);
|
|
mutex_unlock(&all_q_mutex);
|
|
}
|
|
EXPORT_SYMBOL(blk_mq_free_queue);
|
|
|
|
/* Basically redo blk_mq_init_queue with queue frozen */
|
|
static void __cpuinit blk_mq_queue_reinit(struct request_queue *q)
|
|
{
|
|
blk_mq_freeze_queue(q);
|
|
|
|
blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues);
|
|
|
|
/*
|
|
* redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe
|
|
* we should change hctx numa_node according to new topology (this
|
|
* involves free and re-allocate memory, worthy doing?)
|
|
*/
|
|
|
|
blk_mq_map_swqueue(q);
|
|
|
|
blk_mq_unfreeze_queue(q);
|
|
}
|
|
|
|
static int __cpuinit blk_mq_queue_reinit_notify(struct notifier_block *nb,
|
|
unsigned long action, void *hcpu)
|
|
{
|
|
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.
|
|
*/
|
|
if (action != CPU_DEAD && action != CPU_DEAD_FROZEN &&
|
|
action != CPU_ONLINE && action != CPU_ONLINE_FROZEN)
|
|
return NOTIFY_OK;
|
|
|
|
mutex_lock(&all_q_mutex);
|
|
list_for_each_entry(q, &all_q_list, all_q_node)
|
|
blk_mq_queue_reinit(q);
|
|
mutex_unlock(&all_q_mutex);
|
|
return NOTIFY_OK;
|
|
}
|
|
|
|
static int __init blk_mq_init(void)
|
|
{
|
|
unsigned int i;
|
|
|
|
for_each_possible_cpu(i)
|
|
init_llist_head(&per_cpu(ipi_lists, i));
|
|
|
|
blk_mq_cpu_init();
|
|
|
|
/* Must be called after percpu_counter_hotcpu_callback() */
|
|
hotcpu_notifier(blk_mq_queue_reinit_notify, -10);
|
|
|
|
return 0;
|
|
}
|
|
subsys_initcall(blk_mq_init);
|