Add a blk-mq equivalent to blk_delay_queue so that the scsi layer can ask
to be kicked again after a delay.
Signed-off-by: Christoph Hellwig <h...@lst.de>
---
block/blk-core.c | 6 ++++--
block/blk-mq.c | 47 +++++++++++++++++++++++++++++++++++++++++------
include/linux/blk-mq.h | 4 +++-
3 files changed, 48 insertions(+), 9 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index ae6227f..90b6e63 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -251,8 +251,10 @@ void blk_sync_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);
+ queue_for_each_hw_ctx(q, hctx, i) {
+ cancel_delayed_work_sync(&hctx->run_work);
+ cancel_delayed_work_sync(&hctx->delay_work);
+ }
} else {
cancel_delayed_work_sync(&q->delay_work);
}
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 8a080c2..128b5e5 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -638,7 +638,7 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool
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->delayed_work, 0);
+ kblockd_schedule_delayed_work(&hctx->run_work, 0);
else {
unsigned int cpu;
@@ -649,7 +649,7 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool
async)
* just queue on the first CPU.
*/
cpu = cpumask_first(hctx->cpumask);
- kblockd_schedule_delayed_work_on(cpu, &hctx->delayed_work, 0);
+ kblockd_schedule_delayed_work_on(cpu, &hctx->run_work, 0);
}
}
@@ -673,7 +673,8 @@ 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);
@@ -715,17 +716,50 @@ void blk_mq_start_stopped_hw_queues(struct request_queue
*q, bool async)
}
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);
preempt_disable();
__blk_mq_run_hw_queue(hctx);
preempt_enable();
}
+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);
+
+ preempt_disable();
+ if (test_and_clear_bit(BLK_MQ_S_STOPPED, &hctx->state))
+ __blk_mq_run_hw_queue(hctx);
+ preempt_enable();
+}
+
+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;
+
+ /*
+ * It'd be great if the workqueue API had a way to pass
+ * in a mask and had some smarts for more clever placement
+ * than the first CPU. Or we could round-robin here. For now,
+ * just queue on the first CPU.
+ */
+ cpu = cpumask_first(hctx->cpumask);
+ 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)
{
@@ -1179,7 +1213,8 @@ static int blk_mq_init_hw_queues(struct request_queue *q,
if (node == NUMA_NO_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;
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 9ecfab9..ae868e7 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -18,7 +18,8 @@ struct blk_mq_hw_ctx {
} ____cacheline_aligned_in_smp;
unsigned long state; /* BLK_MQ_S_* flags */
- struct delayed_work delayed_work;
+ struct delayed_work run_work;
+ struct delayed_work delay_work;
cpumask_var_t cpumask;
unsigned long flags; /* BLK_MQ_F_* flags */
@@ -158,6 +159,7 @@ void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx);
void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx);
void blk_mq_stop_hw_queues(struct request_queue *q);
void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async);
+void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs);
/*
* Driver command data is immediately after the request. So subtract request
--
1.7.10.4
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