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authorChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>2019-08-23 06:45:15 +0200
committerJens Axboe <axboe@kernel.dk>2019-08-23 14:58:04 +0200
commitadb84284796be4989dc3b48c7eef2784af45431d (patch)
tree3f8faf3f7bd9648034999249b651f2676f3b3d1d /drivers/block/null_blk_main.c
parentnull_blk: move duplicate code to callers (diff)
downloadlinux-adb84284796be4989dc3b48c7eef2784af45431d.tar.xz
linux-adb84284796be4989dc3b48c7eef2784af45431d.zip
null_blk: create a helper for throttling
This patch creates a helper for handling throttling code in the null_handle_cmd(). Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers/block/null_blk_main.c')
-rw-r--r--drivers/block/null_blk_main.c39
1 files changed, 25 insertions, 14 deletions
diff --git a/drivers/block/null_blk_main.c b/drivers/block/null_blk_main.c
index 7277f2db8ec9..751679fadc9d 100644
--- a/drivers/block/null_blk_main.c
+++ b/drivers/block/null_blk_main.c
@@ -1133,28 +1133,39 @@ static void null_restart_queue_async(struct nullb *nullb)
blk_mq_start_stopped_hw_queues(q, true);
}
+static inline blk_status_t null_handle_throttled(struct nullb_cmd *cmd)
+{
+ struct nullb_device *dev = cmd->nq->dev;
+ struct nullb *nullb = dev->nullb;
+ blk_status_t sts = BLK_STS_OK;
+ struct request *rq = cmd->rq;
+
+ if (!hrtimer_active(&nullb->bw_timer))
+ hrtimer_restart(&nullb->bw_timer);
+
+ if (atomic_long_sub_return(blk_rq_bytes(rq), &nullb->cur_bytes) < 0) {
+ null_stop_queue(nullb);
+ /* race with timer */
+ if (atomic_long_read(&nullb->cur_bytes) > 0)
+ null_restart_queue_async(nullb);
+ /* requeue request */
+ sts = BLK_STS_DEV_RESOURCE;
+ }
+ return sts;
+}
+
static blk_status_t null_handle_cmd(struct nullb_cmd *cmd, sector_t sector,
sector_t nr_sectors, enum req_opf op)
{
struct nullb_device *dev = cmd->nq->dev;
struct nullb *nullb = dev->nullb;
+ blk_status_t sts;
int err = 0;
if (test_bit(NULLB_DEV_FL_THROTTLED, &dev->flags)) {
- struct request *rq = cmd->rq;
-
- if (!hrtimer_active(&nullb->bw_timer))
- hrtimer_restart(&nullb->bw_timer);
-
- if (atomic_long_sub_return(blk_rq_bytes(rq),
- &nullb->cur_bytes) < 0) {
- null_stop_queue(nullb);
- /* race with timer */
- if (atomic_long_read(&nullb->cur_bytes) > 0)
- null_restart_queue_async(nullb);
- /* requeue request */
- return BLK_STS_DEV_RESOURCE;
- }
+ sts = null_handle_throttled(cmd);
+ if (sts != BLK_STS_OK)
+ return sts;
}
if (op == REQ_OP_FLUSH) {