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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-05 14:27:02 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-04-05 14:27:02 -0700 |
commit | 3526dd0c7832f1011a0477cc6d903662bae05ea8 (patch) | |
tree | 22fbac64eb40a0b29bfa4c029695f39b2f591e62 /block/blk-cgroup.c | |
parent | dd972f924df6bdbc0ab185a38d5d2361dbc26311 (diff) | |
parent | bc6d65e6dc89c3b7ff78e4ad797117c122ffde8e (diff) | |
download | linux-3526dd0c7832f1011a0477cc6d903662bae05ea8.tar.bz2 |
Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
"It's a pretty quiet round this time, which is nice. This contains:
- series from Bart, cleaning up the way we set/test/clear atomic
queue flags.
- series from Bart, fixing races between gendisk and queue
registration and removal.
- set of bcache fixes and improvements from various folks, by way of
Michael Lyle.
- set of lightnvm updates from Matias, most of it being the 1.2 to
2.0 transition.
- removal of unused DIO flags from Nikolay.
- blk-mq/sbitmap memory ordering fixes from Omar.
- divide-by-zero fix for BFQ from Paolo.
- minor documentation patches from Randy.
- timeout fix from Tejun.
- Alpha "can't write a char atomically" fix from Mikulas.
- set of NVMe fixes by way of Keith.
- bsg and bsg-lib improvements from Christoph.
- a few sed-opal fixes from Jonas.
- cdrom check-disk-change deadlock fix from Maurizio.
- various little fixes, comment fixes, etc from various folks"
* tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits)
blk-mq: Directly schedule q->timeout_work when aborting a request
blktrace: fix comment in blktrace_api.h
lightnvm: remove function name in strings
lightnvm: pblk: remove some unnecessary NULL checks
lightnvm: pblk: don't recover unwritten lines
lightnvm: pblk: implement 2.0 support
lightnvm: pblk: implement get log report chunk
lightnvm: pblk: rename ppaf* to addrf*
lightnvm: pblk: check for supported version
lightnvm: implement get log report chunk helpers
lightnvm: make address conversions depend on generic device
lightnvm: add support for 2.0 address format
lightnvm: normalize geometry nomenclature
lightnvm: complete geo structure with maxoc*
lightnvm: add shorten OCSSD version in geo
lightnvm: add minor version to generic geometry
lightnvm: simplify geometry structure
lightnvm: pblk: refactor init/exit sequences
lightnvm: Avoid validation of default op value
lightnvm: centralize permission check for lightnvm ioctl
...
Diffstat (limited to 'block/blk-cgroup.c')
-rw-r--r-- | block/blk-cgroup.c | 78 |
1 files changed, 62 insertions, 16 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index c2033a232a44..1c16694ae145 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -307,11 +307,28 @@ struct blkcg_gq *blkg_lookup_create(struct blkcg *blkcg, } } +static void blkg_pd_offline(struct blkcg_gq *blkg) +{ + int i; + + lockdep_assert_held(blkg->q->queue_lock); + lockdep_assert_held(&blkg->blkcg->lock); + + for (i = 0; i < BLKCG_MAX_POLS; i++) { + struct blkcg_policy *pol = blkcg_policy[i]; + + if (blkg->pd[i] && !blkg->pd[i]->offline && + pol->pd_offline_fn) { + pol->pd_offline_fn(blkg->pd[i]); + blkg->pd[i]->offline = true; + } + } +} + static void blkg_destroy(struct blkcg_gq *blkg) { struct blkcg *blkcg = blkg->blkcg; struct blkcg_gq *parent = blkg->parent; - int i; lockdep_assert_held(blkg->q->queue_lock); lockdep_assert_held(&blkcg->lock); @@ -320,13 +337,6 @@ static void blkg_destroy(struct blkcg_gq *blkg) WARN_ON_ONCE(list_empty(&blkg->q_node)); WARN_ON_ONCE(hlist_unhashed(&blkg->blkcg_node)); - for (i = 0; i < BLKCG_MAX_POLS; i++) { - struct blkcg_policy *pol = blkcg_policy[i]; - - if (blkg->pd[i] && pol->pd_offline_fn) - pol->pd_offline_fn(blkg->pd[i]); - } - if (parent) { blkg_rwstat_add_aux(&parent->stat_bytes, &blkg->stat_bytes); blkg_rwstat_add_aux(&parent->stat_ios, &blkg->stat_ios); @@ -369,6 +379,7 @@ static void blkg_destroy_all(struct request_queue *q) struct blkcg *blkcg = blkg->blkcg; spin_lock(&blkcg->lock); + blkg_pd_offline(blkg); blkg_destroy(blkg); spin_unlock(&blkcg->lock); } @@ -995,25 +1006,25 @@ static struct cftype blkcg_legacy_files[] = { * @css: css of interest * * This function is called when @css is about to go away and responsible - * for shooting down all blkgs associated with @css. blkgs should be - * removed while holding both q and blkcg locks. As blkcg lock is nested - * inside q lock, this function performs reverse double lock dancing. + * for offlining all blkgs pd and killing all wbs associated with @css. + * blkgs pd offline should be done while holding both q and blkcg locks. + * As blkcg lock is nested inside q lock, this function performs reverse + * double lock dancing. * * This is the blkcg counterpart of ioc_release_fn(). */ static void blkcg_css_offline(struct cgroup_subsys_state *css) { struct blkcg *blkcg = css_to_blkcg(css); + struct blkcg_gq *blkg; spin_lock_irq(&blkcg->lock); - while (!hlist_empty(&blkcg->blkg_list)) { - struct blkcg_gq *blkg = hlist_entry(blkcg->blkg_list.first, - struct blkcg_gq, blkcg_node); + hlist_for_each_entry(blkg, &blkcg->blkg_list, blkcg_node) { struct request_queue *q = blkg->q; if (spin_trylock(q->queue_lock)) { - blkg_destroy(blkg); + blkg_pd_offline(blkg); spin_unlock(q->queue_lock); } else { spin_unlock_irq(&blkcg->lock); @@ -1027,11 +1038,43 @@ static void blkcg_css_offline(struct cgroup_subsys_state *css) wb_blkcg_offline(blkcg); } +/** + * blkcg_destroy_all_blkgs - destroy all blkgs associated with a blkcg + * @blkcg: blkcg of interest + * + * This function is called when blkcg css is about to free and responsible for + * destroying all blkgs associated with @blkcg. + * blkgs should be removed while holding both q and blkcg locks. As blkcg lock + * is nested inside q lock, this function performs reverse double lock dancing. + */ +static void blkcg_destroy_all_blkgs(struct blkcg *blkcg) +{ + spin_lock_irq(&blkcg->lock); + while (!hlist_empty(&blkcg->blkg_list)) { + struct blkcg_gq *blkg = hlist_entry(blkcg->blkg_list.first, + struct blkcg_gq, + blkcg_node); + struct request_queue *q = blkg->q; + + if (spin_trylock(q->queue_lock)) { + blkg_destroy(blkg); + spin_unlock(q->queue_lock); + } else { + spin_unlock_irq(&blkcg->lock); + cpu_relax(); + spin_lock_irq(&blkcg->lock); + } + } + spin_unlock_irq(&blkcg->lock); +} + static void blkcg_css_free(struct cgroup_subsys_state *css) { struct blkcg *blkcg = css_to_blkcg(css); int i; + blkcg_destroy_all_blkgs(blkcg); + mutex_lock(&blkcg_pol_mutex); list_del(&blkcg->all_blkcgs_node); @@ -1371,8 +1414,11 @@ void blkcg_deactivate_policy(struct request_queue *q, spin_lock(&blkg->blkcg->lock); if (blkg->pd[pol->plid]) { - if (pol->pd_offline_fn) + if (!blkg->pd[pol->plid]->offline && + pol->pd_offline_fn) { pol->pd_offline_fn(blkg->pd[pol->plid]); + blkg->pd[pol->plid]->offline = true; + } pol->pd_free_fn(blkg->pd[pol->plid]); blkg->pd[pol->plid] = NULL; } |