[RFC,1/7] blk-mq: add new state of BLK_MQ_S_INTERNAL_STOPPED
diff mbox series

Message ID 20190712024726.1227-2-ming.lei@redhat.com
State New
Headers show
Series
  • blk-mq: improvement on handling IO during CPU hotplug
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Commit Message

Ming Lei July 12, 2019, 2:47 a.m. UTC
Add a new hw queue state of BLK_MQ_S_INTERNAL_STOPPED, which prepares
for stopping hw queue before all CPUs of this hctx become offline.

We can't reuse BLK_MQ_S_STOPPED because that state can be cleared during IO
completion.

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>
Cc: Keith Busch <keith.busch@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
 block/blk-mq-debugfs.c | 1 +
 block/blk-mq.h         | 3 ++-
 include/linux/blk-mq.h | 3 +++
 3 files changed, 6 insertions(+), 1 deletion(-)

Patch
diff mbox series

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index b3f2ba483992..af40a02c46ee 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -213,6 +213,7 @@  static const char *const hctx_state_name[] = {
 	HCTX_STATE_NAME(STOPPED),
 	HCTX_STATE_NAME(TAG_ACTIVE),
 	HCTX_STATE_NAME(SCHED_RESTART),
+	HCTX_STATE_NAME(INTERNAL_STOPPED),
 };
 #undef HCTX_STATE_NAME
 
diff --git a/block/blk-mq.h b/block/blk-mq.h
index f4bf5161333e..9d821adf5765 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -176,7 +176,8 @@  static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data
 
 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
 {
-	return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
+	return test_bit(BLK_MQ_S_STOPPED, &hctx->state) ||
+		test_bit(BLK_MQ_S_INTERNAL_STOPPED, &hctx->state);
 }
 
 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 3fa1fa59f9b2..3a731c3c0762 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -228,6 +228,9 @@  enum {
 	BLK_MQ_S_TAG_ACTIVE	= 1,
 	BLK_MQ_S_SCHED_RESTART	= 2,
 
+	/* hw queue is internal stopped, driver do not use it */
+	BLK_MQ_S_INTERNAL_STOPPED	= 3,
+
 	BLK_MQ_MAX_DEPTH	= 10240,
 
 	BLK_MQ_CPU_WORK_BATCH	= 8,