[PATCH 4.14 069/189] blk-mq: fix sysfs inflight counter

Greg Kroah-Hartman
2018-06-18T09:04:44Z

From: Omar Sandoval <osandov@fb.com>

[ Upstream commit bf0ddaba65ddbb2715af97041da8e7a45b2d8628 ]

When the blk-mq inflight implementation was added, /proc/diskstats was
converted to use it, but /sys/block/$dev/inflight was not. Fix it by
adding another helper to count in-flight requests by data direction.

Fixes: f299b7c7a9de ("blk-mq: provide internal in-flight variant")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
block/blk-mq.c | 19 +++++++++++++++++++
block/blk-mq.h | 4 +++-
block/genhd.c | 12 ++++++++++++
block/partition-generic.c | 10 ++++++----
include/linux/genhd.h | 4 +++-
5 files changed, 43 insertions(+), 6 deletions(-)

--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -118,6 +118,25 @@ void blk_mq_in_flight(struct request_que
blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight, &mi);
}

+static void blk_mq_check_inflight_rw(struct blk_mq_hw_ctx *hctx,
+ struct request *rq, void *priv,
+ bool reserved)
+{
+ struct mq_inflight *mi = priv;
+
+ if (rq->part == mi->part)
+ mi->inflight[rq_data_dir(rq)]++;
+}
+
+void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2])
+{
+ struct mq_inflight mi = { .part = part, .inflight = inflight, };
+
+ inflight[0] = inflight[1] = 0;
+ blk_mq_queue_tag_busy_iter(q, blk_mq_check_inflight_rw, &mi);
+}
+
void blk_freeze_queue_start(struct request_queue *q)
{
int freeze_depth;
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -136,6 +136,8 @@ static inline bool blk_mq_hw_queue_mappe
}

void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
- unsigned int inflight[2]);
+ unsigned int inflight[2]);
+void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2]);

#endif
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -82,6 +82,18 @@ void part_in_flight(struct request_queue
}
}

+void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2])
+{
+ if (q->mq_ops) {
+ blk_mq_in_flight_rw(q, part, inflight);
+ return;
+ }
+
+ inflight[0] = atomic_read(&part->in_flight[0]);
+ inflight[1] = atomic_read(&part->in_flight[1]);
+}
+
struct hd_struct *__disk_get_part(struct gendisk *disk, int partno)
{
struct disk_part_tbl *ptbl = rcu_dereference(disk->part_tbl);
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -145,13 +145,15 @@ ssize_t part_stat_show(struct device *de
jiffies_to_msecs(part_stat_read(p, time_in_queue)));
}

-ssize_t part_inflight_show(struct device *dev,
- struct device_attribute *attr, char *buf)
+ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
{
struct hd_struct *p = dev_to_part(dev);
+ struct request_queue *q = part_to_disk(p)->queue;
+ unsigned int inflight[2];

- return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
- atomic_read(&p->in_flight[1]));
+ part_in_flight_rw(q, p, inflight);
+ return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
}

#ifdef CONFIG_FAIL_MAKE_REQUEST
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -365,7 +365,9 @@ static inline void free_part_stats(struc
part_stat_add(cpu, gendiskp, field, -subnd)

void part_in_flight(struct request_queue *q, struct hd_struct *part,
- unsigned int inflight[2]);
+ unsigned int inflight[2]);
+void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2]);
void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
int rw);
void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,