locking/atomic, kref: Add kref_read()
Since we need to change the implementation, stop exposing internals.
Provide kref_read() to read the current reference count; typically
used for debug messages.
Kills two anti-patterns:
atomic_read(&kref->refcount)
kref->refcount.counter
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 36d2b9f..436baa6 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -1535,7 +1535,7 @@
static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
{
dout("%s: obj %p (was %d)\n", __func__, obj_request,
- atomic_read(&obj_request->kref.refcount));
+ kref_read(&obj_request->kref));
kref_get(&obj_request->kref);
}
@@ -1544,14 +1544,14 @@
{
rbd_assert(obj_request != NULL);
dout("%s: obj %p (was %d)\n", __func__, obj_request,
- atomic_read(&obj_request->kref.refcount));
+ kref_read(&obj_request->kref));
kref_put(&obj_request->kref, rbd_obj_request_destroy);
}
static void rbd_img_request_get(struct rbd_img_request *img_request)
{
dout("%s: img %p (was %d)\n", __func__, img_request,
- atomic_read(&img_request->kref.refcount));
+ kref_read(&img_request->kref));
kref_get(&img_request->kref);
}
@@ -1562,7 +1562,7 @@
{
rbd_assert(img_request != NULL);
dout("%s: img %p (was %d)\n", __func__, img_request,
- atomic_read(&img_request->kref.refcount));
+ kref_read(&img_request->kref));
if (img_request_child_test(img_request))
kref_put(&img_request->kref, rbd_parent_request_destroy);
else