[PATCH] blk-sysfs: Rework documention of __blk_release_queue

From: Marcos Paulo de Souza
Date: Wed Jan 30 2019 - 20:11:13 EST


The Notes section of the comment was removed, because now
blk_release_queue can only be executed from blk_cleanup_queue (being
called when the q->kobj reaches zero), and also blk_init_queue was removed
in a1ce35fa4985.

Signed-off-by: Marcos Paulo de Souza <marcos.souza.org@xxxxxxxxx>
---
This is basically a v2 of https://lkml.org/lkml/2019/1/14/1098

But, I tried to describe when this function is called, removing redundancies.
Maybe it would be better placed in blk-core.c, where the q->kobj is initialized
with blk_queue_ktype (which .release pointer points to blk_release_queue)?

block/blk-sysfs.c | 19 +++++++------------
1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 590d1ef2f961..d4dea9179fa6 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -817,21 +817,16 @@ static void blk_free_queue_rcu(struct rcu_head *rcu_head)
}

/**
- * __blk_release_queue - release a request queue when it is no longer needed
+ * __blk_release_queue - release a request queue
* @work: pointer to the release_work member of the request queue to be released
*
* Description:
- * blk_release_queue is the counterpart of blk_init_queue(). It should be
- * called when a request queue is being released; typically when a block
- * device is being de-registered. Its primary task it to free the queue
- * itself.
- *
- * Notes:
- * The low level driver must have finished any outstanding requests first
- * via blk_cleanup_queue().
- *
- * Although blk_release_queue() may be called with preemption disabled,
- * __blk_release_queue() may sleep.
+ * This function is called when a block device is being de-registered. The
+ * process of releasing a request queue starts with blk_cleanup_queue, which
+ * set the appropriate flags and the calls blk_put_queue, that decrements
+ * the reference counter of the request queue. Once the reference counter
+ * of the request queue reaches zero, blk_release_queue is called to release
+ * all allocated resources of the request queue.
*/
static void __blk_release_queue(struct work_struct *work)
{
--
2.16.4