[PATCH 05/10] block/rq_qos: implement rq_qos_ops->queue_depth_changed()

From: Tejun Heo
Date: Wed Aug 28 2019 - 18:06:26 EST


wbt already gets queue depth changed notification through
wbt_set_queue_depth(). Generalize it into
rq_qos_ops->queue_depth_changed() so that other rq_qos policies can
easily hook into the events too.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
block/blk-rq-qos.c | 9 +++++++++
block/blk-rq-qos.h | 8 ++++++++
block/blk-settings.c | 2 +-
block/blk-wbt.c | 18 ++++++++----------
block/blk-wbt.h | 4 ----
5 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c
index f4eea78f5cc1..61b635bc2a31 100644
--- a/block/blk-rq-qos.c
+++ b/block/blk-rq-qos.c
@@ -101,6 +101,15 @@ void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio)
} while (rqos);
}

+void __rq_qos_queue_depth_changed(struct rq_qos *rqos)
+{
+ do {
+ if (rqos->ops->queue_depth_changed)
+ rqos->ops->queue_depth_changed(rqos);
+ rqos = rqos->next;
+ } while (rqos);
+}
+
/*
* Return true, if we can't increase the depth further by scaling
*/
diff --git a/block/blk-rq-qos.h b/block/blk-rq-qos.h
index 8e426a8505b6..e15b6907b76d 100644
--- a/block/blk-rq-qos.h
+++ b/block/blk-rq-qos.h
@@ -41,6 +41,7 @@ struct rq_qos_ops {
void (*done)(struct rq_qos *, struct request *);
void (*done_bio)(struct rq_qos *, struct bio *);
void (*cleanup)(struct rq_qos *, struct bio *);
+ void (*queue_depth_changed)(struct rq_qos *);
void (*exit)(struct rq_qos *);
const struct blk_mq_debugfs_attr *debugfs_attrs;
};
@@ -138,6 +139,7 @@ void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio);
void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio);
void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio);
void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio);
+void __rq_qos_queue_depth_changed(struct rq_qos *rqos);

static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio)
{
@@ -194,6 +196,12 @@ static inline void rq_qos_merge(struct request_queue *q, struct request *rq,
__rq_qos_merge(q->rq_qos, rq, bio);
}

+static inline void rq_qos_queue_depth_changed(struct request_queue *q)
+{
+ if (q->rq_qos)
+ __rq_qos_queue_depth_changed(q->rq_qos);
+}
+
void rq_qos_exit(struct request_queue *);

#endif
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 2c1831207a8f..a058997b9cce 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -805,7 +805,7 @@ EXPORT_SYMBOL(blk_queue_update_dma_alignment);
void blk_set_queue_depth(struct request_queue *q, unsigned int depth)
{
q->queue_depth = depth;
- wbt_set_queue_depth(q, depth);
+ rq_qos_queue_depth_changed(q);
}
EXPORT_SYMBOL(blk_set_queue_depth);

diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index c4d3089e47f7..8af553a0ba00 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -629,15 +629,6 @@ static void wbt_requeue(struct rq_qos *rqos, struct request *rq)
}
}

-void wbt_set_queue_depth(struct request_queue *q, unsigned int depth)
-{
- struct rq_qos *rqos = wbt_rq_qos(q);
- if (rqos) {
- RQWB(rqos)->rq_depth.queue_depth = depth;
- __wbt_update_limits(RQWB(rqos));
- }
-}
-
void wbt_set_write_cache(struct request_queue *q, bool write_cache_on)
{
struct rq_qos *rqos = wbt_rq_qos(q);
@@ -689,6 +680,12 @@ static int wbt_data_dir(const struct request *rq)
return -1;
}

+static void wbt_queue_depth_changed(struct rq_qos *rqos)
+{
+ RQWB(rqos)->rq_depth.queue_depth = blk_queue_depth(rqos->q);
+ __wbt_update_limits(RQWB(rqos));
+}
+
static void wbt_exit(struct rq_qos *rqos)
{
struct rq_wb *rwb = RQWB(rqos);
@@ -811,6 +808,7 @@ static struct rq_qos_ops wbt_rqos_ops = {
.requeue = wbt_requeue,
.done = wbt_done,
.cleanup = wbt_cleanup,
+ .queue_depth_changed = wbt_queue_depth_changed,
.exit = wbt_exit,
#ifdef CONFIG_BLK_DEBUG_FS
.debugfs_attrs = wbt_debugfs_attrs,
@@ -853,7 +851,7 @@ int wbt_init(struct request_queue *q)

rwb->min_lat_nsec = wbt_default_latency_nsec(q);

- wbt_set_queue_depth(q, blk_queue_depth(q));
+ wbt_queue_depth_changed(&rwb->rqos);
wbt_set_write_cache(q, test_bit(QUEUE_FLAG_WC, &q->queue_flags));

return 0;
diff --git a/block/blk-wbt.h b/block/blk-wbt.h
index f47218d5b3b2..8e4e37660971 100644
--- a/block/blk-wbt.h
+++ b/block/blk-wbt.h
@@ -95,7 +95,6 @@ void wbt_enable_default(struct request_queue *);
u64 wbt_get_min_lat(struct request_queue *q);
void wbt_set_min_lat(struct request_queue *q, u64 val);

-void wbt_set_queue_depth(struct request_queue *, unsigned int);
void wbt_set_write_cache(struct request_queue *, bool);

u64 wbt_default_latency_nsec(struct request_queue *);
@@ -118,9 +117,6 @@ static inline void wbt_disable_default(struct request_queue *q)
static inline void wbt_enable_default(struct request_queue *q)
{
}
-static inline void wbt_set_queue_depth(struct request_queue *q, unsigned int depth)
-{
-}
static inline void wbt_set_write_cache(struct request_queue *q, bool wc)
{
}
--
2.17.1