blk-mq: unify hctx delayed_run_work and run_work

They serve the exact same purpose. Get rid of the non-delayed
work variant, and just run it without delay for the normal case.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

3 files changed, 8 insertions, 24 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 6bd4d1754d29..37939672d4df 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -269,7 +269,7 @@ void blk_sync_queue(struct request_queue *q)
                 int i;
 
                 queue_for_each_hw_ctx(q, hctx, i) {
-                        cancel_work_sync(&hctx->run_work);
+                        cancel_delayed_work_sync(&hctx->run_work);
                         cancel_delayed_work_sync(&hctx->delay_work);
                 }
         } else {
diff --git a/block/blk-mq.c b/block/blk-mq.c
index e6aad49c1686..5c68fce87ffc 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1166,13 +1166,9 @@ static void __blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async,
                 put_cpu();
         }
 
-        if (msecs == 0)
-                kblockd_schedule_work_on(blk_mq_hctx_next_cpu(hctx),
-                                         &hctx->run_work);
-        else
-                kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx),
-                                                 &hctx->delayed_run_work,
-                                                 msecs_to_jiffies(msecs));
+        kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx),
+                                         &hctx->run_work,
+                                         msecs_to_jiffies(msecs));
 }
 
 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs)
@@ -1224,7 +1220,7 @@ EXPORT_SYMBOL(blk_mq_queue_stopped);
 
 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx)
 {
-        cancel_work(&hctx->run_work);
+        cancel_delayed_work_sync(&hctx->run_work);
         cancel_delayed_work(&hctx->delay_work);
         set_bit(BLK_MQ_S_STOPPED, &hctx->state);
 }
@@ -1282,17 +1278,7 @@ 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, run_work);
-
-        __blk_mq_run_hw_queue(hctx);
-}
-
-static void blk_mq_delayed_run_work_fn(struct work_struct *work)
-{
-        struct blk_mq_hw_ctx *hctx;
-
-        hctx = container_of(work, struct blk_mq_hw_ctx, delayed_run_work.work);
-
+        hctx = container_of(work, struct blk_mq_hw_ctx, run_work.work);
         __blk_mq_run_hw_queue(hctx);
 }
 
@@ -1898,8 +1884,7 @@ static int blk_mq_init_hctx(struct request_queue *q,
         if (node == NUMA_NO_NODE)
                 node = hctx->numa_node = set->numa_node;
 
-        INIT_WORK(&hctx->run_work, blk_mq_run_work_fn);
-        INIT_DELAYED_WORK(&hctx->delayed_run_work, blk_mq_delayed_run_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);
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 32bd8eb5ba67..c7cc90328426 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -15,7 +15,7 @@ struct blk_mq_hw_ctx {
                 unsigned long           state;          /* BLK_MQ_S_* flags */
         } ____cacheline_aligned_in_smp;
 
-        struct work_struct      run_work;
+        struct delayed_work     run_work;
         cpumask_var_t           cpumask;
         int                     next_cpu;
         int                     next_cpu_batch;
@@ -51,7 +51,6 @@ struct blk_mq_hw_ctx {
 
         atomic_t                nr_active;
 
-        struct delayed_work     delayed_run_work;
         struct delayed_work     delay_work;
 
         struct hlist_node       cpuhp_dead;