[PATCH V3 4/7] ublk_drv: requeue rqs with recovery feature enabled

From: ZiyangZhang
Date: Tue Sep 13 2022 - 00:19:20 EST


With recovery feature enabled, in ublk_queue_rq or task work
(in exit_task_work or fallback wq), we requeue rqs instead of
ending(aborting) them. Besides, No matter recovery feature is enabled
or disabled, we schedule monitor_work immediately.

Signed-off-by: ZiyangZhang <ZiyangZhang@xxxxxxxxxxxxxxxxx>
---
drivers/block/ublk_drv.c | 34 ++++++++++++++++++++++++++++++++--
1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 23337bd7c105..b067f33a1913 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -682,6 +682,21 @@ static void ubq_complete_io_cmd(struct ublk_io *io, int res)

#define UBLK_REQUEUE_DELAY_MS 3

+static inline void __ublk_abort_rq_in_task_work(struct ublk_queue *ubq,
+ struct request *rq)
+{
+ pr_devel("%s: %s q_id %d tag %d io_flags %x.\n", __func__,
+ (ublk_queue_can_use_recovery(ubq)) ? "requeue" : "abort",
+ ubq->q_id, rq->tag, ubq->ios[rq->tag].flags);
+ /* We cannot process this rq so just requeue it. */
+ if (ublk_queue_can_use_recovery(ubq)) {
+ blk_mq_requeue_request(rq, false);
+ blk_mq_delay_kick_requeue_list(rq->q, UBLK_REQUEUE_DELAY_MS);
+ } else {
+ blk_mq_end_request(rq, BLK_STS_IOERR);
+ }
+}
+
static inline void __ublk_rq_task_work(struct request *req)
{
struct ublk_queue *ubq = req->mq_hctx->driver_data;
@@ -704,7 +719,7 @@ static inline void __ublk_rq_task_work(struct request *req)
* (2) current->flags & PF_EXITING.
*/
if (unlikely(current != ubq->ubq_daemon || current->flags & PF_EXITING)) {
- blk_mq_end_request(req, BLK_STS_IOERR);
+ __ublk_abort_rq_in_task_work(ubq, req);
mod_delayed_work(system_wq, &ub->monitor_work, 0);
return;
}
@@ -779,6 +794,21 @@ static void ublk_rq_task_work_fn(struct callback_head *work)
__ublk_rq_task_work(req);
}

+static inline blk_status_t __ublk_abort_rq(struct ublk_queue *ubq,
+ struct request *rq)
+{
+ pr_devel("%s: %s q_id %d tag %d io_flags %x.\n", __func__,
+ (ublk_queue_can_use_recovery(ubq)) ? "requeue" : "abort",
+ ubq->q_id, rq->tag, ubq->ios[rq->tag].flags);
+ /* We cannot process this rq so just requeue it. */
+ if (ublk_queue_can_use_recovery(ubq)) {
+ blk_mq_requeue_request(rq, false);
+ blk_mq_delay_kick_requeue_list(rq->q, UBLK_REQUEUE_DELAY_MS);
+ return BLK_STS_OK;
+ }
+ return BLK_STS_IOERR;
+}
+
static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
@@ -796,7 +826,7 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx,
if (unlikely(ubq_daemon_is_dying(ubq))) {
fail:
mod_delayed_work(system_wq, &ubq->dev->monitor_work, 0);
- return BLK_STS_IOERR;
+ return __ublk_abort_rq(ubq, rq);
}

if (ublk_can_use_task_work(ubq)) {
--
2.27.0