blk-mq: factor out a helper to reise the block softirq

Add a helper to deduplicate the logic that raises the block softirq.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 60febbf..a261e14 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -598,19 +598,27 @@ static __latent_entropy void blk_done_softirq(struct softirq_action *h)
        }
 }
 
-#ifdef CONFIG_SMP
-static void trigger_softirq(void *data)
+static void blk_mq_trigger_softirq(struct request *rq)
 {
-       struct request *rq = data;
-       struct list_head *list;
+       struct list_head *list = this_cpu_ptr(&blk_cpu_done);
 
-       list = this_cpu_ptr(&blk_cpu_done);
        list_add_tail(&rq->ipi_list, list);
 
+       /*
+        * If the list only contains our just added request, signal a raise of
+        * the softirq.  If there are already entries there, someone already
+        * raised the irq but it hasn't run yet.
+        */
        if (list->next == &rq->ipi_list)
                raise_softirq_irqoff(BLOCK_SOFTIRQ);
 }
 
+#ifdef CONFIG_SMP
+static void trigger_softirq(void *data)
+{
+       blk_mq_trigger_softirq(data);
+}
+
 /*
  * Setup and invoke a run of 'trigger_softirq' on the given cpu.
  */
@@ -681,19 +689,8 @@ static void __blk_complete_request(struct request *req)
         * avoids IPI sending from current CPU to the first CPU of a group.
         */
        if (ccpu == cpu || shared) {
-               struct list_head *list;
 do_local:
-               list = this_cpu_ptr(&blk_cpu_done);
-               list_add_tail(&req->ipi_list, list);
-
-               /*
-                * if the list only contains our just added request,
-                * signal a raise of the softirq. If there are already
-                * entries there, someone already raised the irq but it
-                * hasn't run yet.
-                */
-               if (list->next == &req->ipi_list)
-                       raise_softirq_irqoff(BLOCK_SOFTIRQ);
+               blk_mq_trigger_softirq(req);
        } else if (raise_blk_irq(ccpu, req))
                goto do_local;