[PATCHv2 1/5] block: support polling through blk_execute_rq

Keith Busch
2021-04-23T22:06:42Z

Poll for completions if the request's hctx is a polling type.

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
block/blk-exec.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/block/blk-exec.c b/block/blk-exec.c
index beae70a0e5e5..b960ad187ba5 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -63,6 +63,11 @@ void blk_execute_rq_nowait(struct gendisk *bd_disk, struct request *rq,
}
EXPORT_SYMBOL_GPL(blk_execute_rq_nowait);

+static bool blk_rq_is_poll(struct request *rq)
+{
+ return rq->mq_hctx && rq->mq_hctx->type == HCTX_TYPE_POLL;
+}
+
/**
* blk_execute_rq - insert a request into queue for execution
* @bd_disk: matching gendisk
@@ -83,7 +88,12 @@ void blk_execute_rq(struct gendisk *bd_disk, struct request *rq, int at_head)

/* Prevent hang_check timer from firing at us during very long I/O */
hang_check = sysctl_hung_task_timeout_secs;
- if (hang_check)
+ if (blk_rq_is_poll(rq)) {
+ do {
+ blk_poll(rq->q, request_to_qc_t(rq->mq_hctx, rq), true);
+ cond_resched();
+ } while (!completion_done(&wait));
+ } else if (hang_check)
while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2)));
else
wait_for_completion_io(&wait);
--
2.25.4