block: expose the statistics in blkio.time and blkio.sectors for the root cgroup

Currently, the io statistics for the root cgroup are maintained, but
they are not shown because the device information is not available at
the point that the root blkio cgroup is created. This patch updates
the device information when the statistics are updated so that the
statistics become visible.

Signed-off-by: Ricky Benitez <rickyb@google.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Ricky Benitez 2010-04-05 18:22:17 +02:00 committed by Jens Axboe
parent 1442145373
commit a74b2adae0

View File

@ -948,6 +948,11 @@ cfq_find_alloc_cfqg(struct cfq_data *cfqd, struct cgroup *cgroup, int create)
unsigned int major, minor;
cfqg = cfqg_of_blkg(blkiocg_lookup_group(blkcg, key));
if (cfqg && !cfqg->blkg.dev && bdi->dev && dev_name(bdi->dev)) {
sscanf(dev_name(bdi->dev), "%u:%u", &major, &minor);
cfqg->blkg.dev = MKDEV(major, minor);
goto done;
}
if (cfqg || !create)
goto done;