diff options
author | Dennis Zhou <dennis@kernel.org> | 2018-11-01 17:24:10 -0400 |
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committer | Jens Axboe <axboe@kernel.dk> | 2018-11-01 19:59:53 -0600 |
commit | b5f2954d30c77649bce9c27e7a0a94299d9cfdf8 (patch) | |
tree | f5dd932dc087c3a60410e82c70be1daf92d350a7 /block/blk-iolatency.c | |
parent | 153fcd5f6d93b8e1e4040b1337f564a10f8d93af (diff) | |
download | linux-b5f2954d30c77649bce9c27e7a0a94299d9cfdf8.tar.bz2 |
blkcg: revert blkcg cleanups series
This reverts a series committed earlier due to null pointer exception
bug report in [1]. It seems there are edge case interactions that I did
not consider and will need some time to understand what causes the
adverse interactions.
The original series can be found in [2] with a follow up series in [3].
[1] https://www.spinics.net/lists/cgroups/msg20719.html
[2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/
[3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/
This reverts the following commits:
d459d853c2ed, b2c3fa546705, 101246ec02b5, b3b9f24f5fcc, e2b0989954ae,
f0fcb3ec89f3, c839e7a03f92, bdc2491708c4, 74b7c02a9bc1, 5bf9a1f3b4ef,
a7b39b4e961c, 07b05bcc3213, 49f4c2dc2b50, 27e6fa996c53
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-iolatency.c')
-rw-r--r-- | block/blk-iolatency.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c index 35c48d7b8f78..bb240a0c1309 100644 --- a/block/blk-iolatency.c +++ b/block/blk-iolatency.c @@ -480,12 +480,34 @@ static void blkcg_iolatency_throttle(struct rq_qos *rqos, struct bio *bio, spinlock_t *lock) { struct blk_iolatency *blkiolat = BLKIOLATENCY(rqos); - struct blkcg_gq *blkg = bio->bi_blkg; + struct blkcg *blkcg; + struct blkcg_gq *blkg; + struct request_queue *q = rqos->q; bool issue_as_root = bio_issue_as_root_blkg(bio); if (!blk_iolatency_enabled(blkiolat)) return; + rcu_read_lock(); + blkcg = bio_blkcg(bio); + bio_associate_blkcg(bio, &blkcg->css); + blkg = blkg_lookup(blkcg, q); + if (unlikely(!blkg)) { + if (!lock) + spin_lock_irq(q->queue_lock); + blkg = blkg_lookup_create(blkcg, q); + if (IS_ERR(blkg)) + blkg = NULL; + if (!lock) + spin_unlock_irq(q->queue_lock); + } + if (!blkg) + goto out; + + bio_issue_init(&bio->bi_issue, bio_sectors(bio)); + bio_associate_blkg(bio, blkg); +out: + rcu_read_unlock(); while (blkg && blkg->parent) { struct iolatency_grp *iolat = blkg_to_lat(blkg); if (!iolat) { @@ -706,7 +728,7 @@ static void blkiolatency_timer_fn(struct timer_list *t) * We could be exiting, don't access the pd unless we have a * ref on the blkg. */ - if (!blkg_tryget(blkg)) + if (!blkg_try_get(blkg)) continue; iolat = blkg_to_lat(blkg); |