diff options
| author | Dennis Zhou <dennis@kernel.org> | 2018-12-05 20:10:31 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-12-08 08:26:37 +0300 |
| commit | 5cdf2e3fea5ee37b66842d76a9b06e6dac0b933d (patch) | |
| tree | b460ef1ba02562982e2f000e704ce7214be4d5f3 /include/linux/blk-cgroup.h | |
| parent | 892ad71f622bbf39c6de321d5ca9b0fdec237c24 (diff) | |
| download | linux-5cdf2e3fea5ee37b66842d76a9b06e6dac0b933d.tar.xz | |
blkcg: associate blkg when associating a device
Previously, blkg association was handled by controller specific code in
blk-throttle and blk-iolatency. However, because a blkg represents a
relationship between a blkcg and a request_queue, it makes sense to keep
the blkg->q and bio->bi_disk->queue consistent.
This patch moves association into the bio_set_dev macro(). This should
cover the majority of cases where the device is set/changed keeping the
two pointers consistent. Fallback code is added to
blkcg_bio_issue_check() to catch any missing paths.
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux/blk-cgroup.h')
| -rw-r--r-- | include/linux/blk-cgroup.h | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index c08e96e521ed..f09752968c2a 100644 --- 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; } |