[PATCH 1/2] SCSI: run idle hctx after delay in scsi_mq_get_budget()
From: Ming Lei <hidden>
Date: 2017-10-17 05:04:50
Also in:
linux-scsi, lkml
Subsystem:
scsi subsystem, the rest · Maintainers:
"James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds
If there isn't any outstanding request in this queue, both blk-mq's RESTART and SCSI's builtin RESTART can't work, so we have to deal with this case by running this queue after delay. Fixes: d04b6d97d0a1(scsi: implement .get_budget and .put_budget for blk-mq) Signed-off-by: Ming Lei <redacted> --- drivers/scsi/scsi_lib.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 6f10afaca25b..08c495364b28 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c@@ -1959,6 +1959,14 @@ static void scsi_mq_put_budget(struct blk_mq_hw_ctx *hctx) put_device(&sdev->sdev_gendev); } +static void scsi_mq_run_idle_hctx(struct scsi_device *sdev, + struct blk_mq_hw_ctx *hctx) +{ + if (atomic_read(&sdev->device_busy) == 0 && + !scsi_device_blocked(sdev)) + blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY); +} + static blk_status_t scsi_mq_get_budget(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue;
@@ -1989,6 +1997,7 @@ static blk_status_t scsi_mq_get_budget(struct blk_mq_hw_ctx *hctx) out_put_device: put_device(&sdev->sdev_gendev); out: + scsi_mq_run_idle_hctx(sdev, hctx); return BLK_STS_RESOURCE; }
@@ -2039,9 +2048,7 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, case BLK_STS_OK: break; case BLK_STS_RESOURCE: - if (atomic_read(&sdev->device_busy) == 0 && - !scsi_device_blocked(sdev)) - blk_mq_delay_run_hw_queue(hctx, SCSI_QUEUE_DELAY); + scsi_mq_run_idle_hctx(sdev, hctx); break; default: /*
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2.9.5