Description of problem:
Seeing lots of Error message while Rename of Snapshot and IO is happening on the Parent Image.

Version-Release number of selected component (if applicable):
ceph version 10.2.1-6.el7cp

How reproducible:
2 Times

Steps to Reproduce:
1. Create an Image, take 100 Snap, and protect them.
rbd image 'testing2':
        size 102400 MB in 25600 objects
        order 22 (4096 kB objects)
        block_name_prefix: rbd_data.124d642ae8944a
        format: 2
        features: layering, exclusive-lock, object-map, fast-diff, deep-flatten, journaling
        flags: 
        journal: 124d642ae8944a
        mirroring state: disabled
2.Rename the created snapshot.
for i in {1..100}; do rbd snap rename cephfs_data/testing2@snap$i cephfs_data/testing2@snappey$i; done
3. Start Write-bench on the parent Volume.
rbd bench-write -p cephfs_data --image testing2 --io-size 10240

Started step 2 and 3 in parallel.

Actual results:
Both IO and renaming of snapshot is happening, still i am seeing lots of Error message.

2016-05-30 08:52:11.847718 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists
2016-05-30 08:52:12.293367 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists
2016-05-30 08:52:13.731278 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists
2016-05-30 08:52:16.385266 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists
2016-05-30 08:52:20.514545 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists
2016-05-30 08:52:24.469216 7f8329ffb700 -1 librbd::SnapshotRenameRequest: encountered error: (17) File exists

Expected results:
There should not be any Error message.

Additional info:
Debug logs attached.