perf/qr: Use a ref-ed data to extract content

qr_content_extract used dict_get to get the value of
the GF_CONTENT_KEY key. dict_get does not ref the data
before returning it so QR could be acting on freed memory
if another thread deletes the key before then.
This patch also fixes a race in dict_get_with_ref.

Fix: Use dict_get_with_ref to retrieve the file contents.

> BUG: 1484709
> Signed-off-by: N Balachandran <nbalacha@redhat.com>
> Reviewed-on: https://review.gluster.org/18115
> Smoke: Gluster Build System <jenkins@build.gluster.org>
> Reviewed-by: Amar Tumballi <amarts@redhat.com>
> Tested-by: Raghavendra G <rgowdapp@redhat.com>
> CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
> Reviewed-by: Raghavendra G <rgowdapp@redhat.com>

Change-Id: Ib1a7a70bb92eed7e70747ec530e0b3edc53127ec
BUG: 1486538
(cherry picked from commit 414d3e92fc56f08e320a3aa65b6b18e65b384551)
Signed-off-by: N Balachandran <nbalacha@redhat.com>
Reviewed-on: https://review.gluster.org/18145
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
Smoke: Gluster Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: MOHIT AGRAWAL <moagrawa@redhat.com>

0 files changed, 0 insertions, 0 deletions