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

[firefly-linux-kernel-4.4.55.git] / block / cfq-iosched.c

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 2c7a0f4f3cd7860da6a50c4f066aa1521927cc63..7104ac816fb61966deb68aaa152faa54da5a04fc 100644 (file)
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -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;