blkcg: associate blkg when associating a device

[sfrench/cifs-2.6.git] / include / linux / blk-cgroup.h

diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h
index c08e96e521edd0c331f5895f67df3c319d632690..f09752968c2a3975492084fe22388738a277e8f6 100644 (file)
--- a/include/linux/blk-cgroup.h
+++ b/include/linux/blk-cgroup.h
@@ -21,6 +21,7 @@
 #include <linux/blkdev.h>
 #include <linux/atomic.h>
 #include <linux/kthread.h>
+#include <linux/fs.h>
 
 /* percpu_counter batch for blkg_[rw]stats, per-cpu drift doesn't matter */
 #define BLKG_STAT_CPU_BATCH    (INT_MAX / 2)
@@ -802,21 +803,23 @@ static inline bool blk_throtl_bio(struct request_queue *q, struct blkcg_gq *blkg
 static inline bool blkcg_bio_issue_check(struct request_queue *q,
                                         struct bio *bio)
 {
-       struct blkcg *blkcg;
        struct blkcg_gq *blkg;
        bool throtl = false;
 
-       rcu_read_lock();
+       if (!bio->bi_blkg) {
+               char b[BDEVNAME_SIZE];
+
+               WARN_ONCE(1,
+                         "no blkg associated for bio on block-device: %s\n",
+                         bio_devname(bio, b));
+               bio_associate_blkg(bio);
+       }
 
-       /* associate blkcg if bio hasn't attached one */
-       bio_associate_blkcg(bio, NULL);
-       blkcg = bio_blkcg(bio);
-       blkg = blkg_lookup_create(blkcg, q);
+       blkg = bio->bi_blkg;
 
        throtl = blk_throtl_bio(q, blkg, bio);
 
        if (!throtl) {
-               blkg = blkg ?: q->root_blkg;
                /*
                 * If the bio is flagged with BIO_QUEUE_ENTERED it means this
                 * is a split bio and we would have already accounted for the
@@ -828,7 +831,6 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q,
                blkg_rwstat_add(&blkg->stat_ios, bio->bi_opf, 1);
        }
 
-       rcu_read_unlock();
        return !throtl;
 }