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/virtio_blk.c b/drivers/block/virtio_blk.c
index 5545a67..79a346c 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -767,7 +767,7 @@
/* Stop all the virtqueues. */
vdev->config->reset(vdev);
- refc = atomic_read(&disk_to_dev(vblk->disk)->kobj.kref.refcount);
+ refc = kref_read(&disk_to_dev(vblk->disk)->kobj.kref);
put_disk(vblk->disk);
vdev->config->del_vqs(vdev);
kfree(vblk->vqs);