diff mbox series

[V11,09/12] blk-mq: add blk_mq_hctx_handle_dead_cpu for handling cpu dead

Message ID 20200513034803.1844579-10-ming.lei@redhat.com (mailing list archive)
State New, archived
Headers show
Series blk-mq: improvement CPU hotplug | expand

Commit Message

Ming Lei May 13, 2020, 3:48 a.m. UTC 
Add helper of blk_mq_hctx_handle_dead_cpu for handling cpu dead,
and prepare for handling inactive hctx.

No functional change.

Cc: John Garry <john.garry@huawei.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 block/blk-mq.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

Comments

Christoph Hellwig May 13, 2020, 12:06 p.m. UTC | #1 
On Wed, May 13, 2020 at 11:48:00AM +0800, Ming Lei wrote:
> Add helper of blk_mq_hctx_handle_dead_cpu for handling cpu dead,
> and prepare for handling inactive hctx.

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
diff mbox series

Patch

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 171bbf2fbc56..7c640482fb24 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2402,22 +2402,13 @@  static int blk_mq_hctx_notify_online(unsigned int cpu, struct hlist_node *node)
 	return 0;
 }
 
-/*
- * 'cpu' is going away. splice any existing rq_list entries from this
- * software queue to the hw queue dispatch list, and ensure that it
- * gets run.
- */
-static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node)
+static void blk_mq_hctx_handle_dead_cpu(struct blk_mq_hw_ctx *hctx,
+		unsigned int cpu)
 {
-	struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node,
-			struct blk_mq_hw_ctx, cpuhp_dead);
 	struct blk_mq_ctx *ctx;
 	LIST_HEAD(tmp);
 	enum hctx_type type;
 
-	if (!cpumask_test_cpu(cpu, hctx->cpumask))
-		return 0;
-
 	ctx = __blk_mq_get_ctx(hctx->queue, cpu);
 	type = hctx->type;
 
@@ -2429,13 +2420,27 @@  static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node)
 	spin_unlock(&ctx->lock);
 
 	if (list_empty(&tmp))
-		return 0;
+		return;
 
 	spin_lock(&hctx->lock);
 	list_splice_tail_init(&tmp, &hctx->dispatch);
 	spin_unlock(&hctx->lock);
 
 	blk_mq_run_hw_queue(hctx, true);
+}
+
+/*
+ * 'cpu' is going away. splice any existing rq_list entries from this
+ * software queue to the hw queue dispatch list, and ensure that it
+ * gets run.
+ */
+static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node)
+{
+	struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node,
+			struct blk_mq_hw_ctx, cpuhp_dead);
+
+	if (cpumask_test_cpu(cpu, hctx->cpumask))
+		blk_mq_hctx_handle_dead_cpu(hctx, cpu);
 	return 0;
 }