From: Kent Overstreet Date: Mon, 16 Dec 2013 23:27:25 +0000 (-0800) Subject: bcache: kill closure locking usage X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=cb7a583e6a6ace661a5890803e115d2292a293df;p=openwrt%2Fstaging%2Fblogic.git bcache: kill closure locking usage Signed-off-by: Kent Overstreet --- diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h index dbdbca5a9591..9d062bc56261 100644 --- a/drivers/md/bcache/bcache.h +++ b/drivers/md/bcache/bcache.h @@ -309,7 +309,8 @@ struct cached_dev { struct cache_sb sb; struct bio sb_bio; struct bio_vec sb_bv[1]; - struct closure_with_waitlist sb_write; + struct closure sb_write; + struct semaphore sb_write_mutex; /* Refcount on the cache set. Always nonzero when we're caching. */ atomic_t count; @@ -514,7 +515,8 @@ struct cache_set { uint64_t cached_dev_sectors; struct closure caching; - struct closure_with_waitlist sb_write; + struct closure sb_write; + struct semaphore sb_write_mutex; mempool_t *search; mempool_t *bio_meta; @@ -635,7 +637,8 @@ struct cache_set { unsigned nr_uuids; struct uuid_entry *uuids; BKEY_PADDED(uuid_bucket); - struct closure_with_waitlist uuid_write; + struct closure uuid_write; + struct semaphore uuid_write_mutex; /* * A btree node on disk could have too many bsets for an iterator to fit diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index aaa87b3be9ef..101231f0f399 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -340,9 +340,16 @@ static void btree_complete_write(struct btree *b, struct btree_write *w) w->journal = NULL; } +static void btree_node_write_unlock(struct closure *cl) +{ + struct btree *b = container_of(cl, struct btree, io); + + up(&b->io_mutex); +} + static void __btree_node_write_done(struct closure *cl) { - struct btree *b = container_of(cl, struct btree, io.cl); + struct btree *b = container_of(cl, struct btree, io); struct btree_write *w = btree_prev_write(b); bch_bbio_free(b->bio, b->c); @@ -353,12 +360,12 @@ static void __btree_node_write_done(struct closure *cl) queue_delayed_work(btree_io_wq, &b->work, msecs_to_jiffies(30000)); - closure_return(cl); + closure_return_with_destructor(cl, btree_node_write_unlock); } static void btree_node_write_done(struct closure *cl) { - struct btree *b = container_of(cl, struct btree, io.cl); + struct btree *b = container_of(cl, struct btree, io); struct bio_vec *bv; int n; @@ -371,7 +378,7 @@ static void btree_node_write_done(struct closure *cl) static void btree_node_write_endio(struct bio *bio, int error) { struct closure *cl = bio->bi_private; - struct btree *b = container_of(cl, struct btree, io.cl); + struct btree *b = container_of(cl, struct btree, io); if (error) set_btree_node_io_error(b); @@ -382,7 +389,7 @@ static void btree_node_write_endio(struct bio *bio, int error) static void do_btree_node_write(struct btree *b) { - struct closure *cl = &b->io.cl; + struct closure *cl = &b->io; struct bset *i = b->sets[b->nsets].data; BKEY_PADDED(key) k; @@ -435,7 +442,7 @@ static void do_btree_node_write(struct btree *b) bch_submit_bbio(b->bio, b->c, &k.key, 0); closure_sync(cl); - __btree_node_write_done(cl); + continue_at_nobarrier(cl, __btree_node_write_done, NULL); } } @@ -454,7 +461,8 @@ void bch_btree_node_write(struct btree *b, struct closure *parent) cancel_delayed_work(&b->work); /* If caller isn't waiting for write, parent refcount is cache set */ - closure_lock(&b->io, parent ?: &b->c->cl); + down(&b->io_mutex); + closure_init(&b->io, parent ?: &b->c->cl); clear_bit(BTREE_NODE_dirty, &b->flags); change_bit(BTREE_NODE_write_idx, &b->flags); @@ -554,7 +562,8 @@ static void mca_reinit(struct btree *b) static void mca_data_free(struct btree *b) { struct bset_tree *t = b->sets; - BUG_ON(!closure_is_unlocked(&b->io.cl)); + + BUG_ON(b->io_mutex.count != 1); if (bset_prev_bytes(b) < PAGE_SIZE) kfree(t->prev); @@ -635,7 +644,7 @@ static struct btree *mca_bucket_alloc(struct cache_set *c, INIT_LIST_HEAD(&b->list); INIT_DELAYED_WORK(&b->work, btree_node_write_work); b->c = c; - closure_init_unlocked(&b->io); + sema_init(&b->io_mutex, 1); mca_data_alloc(b, k, gfp); return b; @@ -653,22 +662,29 @@ static int mca_reap(struct btree *b, unsigned min_order, bool flush) BUG_ON(btree_node_dirty(b) && !b->sets[0].data); - if (b->page_order < min_order || - (!flush && - (btree_node_dirty(b) || - atomic_read(&b->io.cl.remaining) != -1))) { - rw_unlock(true, b); - return -ENOMEM; + if (b->page_order < min_order) + goto out_unlock; + + if (!flush) { + if (btree_node_dirty(b)) + goto out_unlock; + + if (down_trylock(&b->io_mutex)) + goto out_unlock; + up(&b->io_mutex); } if (btree_node_dirty(b)) bch_btree_node_write_sync(b); /* wait for any in flight btree write */ - closure_wait_event(&b->io.wait, &cl, - atomic_read(&b->io.cl.remaining) == -1); + down(&b->io_mutex); + up(&b->io_mutex); return 0; +out_unlock: + rw_unlock(true, b); + return -ENOMEM; } static unsigned long bch_mca_scan(struct shrinker *shrink, @@ -918,7 +934,7 @@ static struct btree *mca_alloc(struct cache_set *c, struct bkey *k, int level) if (!b->sets->data) goto err; out: - BUG_ON(!closure_is_unlocked(&b->io.cl)); + BUG_ON(b->io_mutex.count != 1); bkey_copy(&b->key, k); list_move(&b->list, &c->btree_cache); diff --git a/drivers/md/bcache/btree.h b/drivers/md/bcache/btree.h index 767e75570896..d68af7442f70 100644 --- a/drivers/md/bcache/btree.h +++ b/drivers/md/bcache/btree.h @@ -143,7 +143,8 @@ struct btree { struct bset_tree sets[MAX_BSETS]; /* For outstanding btree writes, used as a lock - protects write_idx */ - struct closure_with_waitlist io; + struct closure io; + struct semaphore io_mutex; struct list_head list; struct delayed_work work; diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c index 03cb4d114e16..fab3767d6d28 100644 --- a/drivers/md/bcache/debug.c +++ b/drivers/md/bcache/debug.c @@ -127,9 +127,7 @@ void bch_btree_verify(struct btree *b, struct bset *new) if (!b->c->verify) return; - closure_wait_event(&b->io.wait, &cl, - atomic_read(&b->io.cl.remaining) == -1); - + down(&b->io_mutex); mutex_lock(&b->c->verify_lock); bkey_copy(&v->key, &b->key); @@ -137,8 +135,6 @@ void bch_btree_verify(struct btree *b, struct bset *new) v->level = b->level; bch_btree_node_read(v); - closure_wait_event(&v->io.wait, &cl, - atomic_read(&b->io.cl.remaining) == -1); if (new->keys != v->sets[0].data->keys || memcmp(new->start, @@ -167,6 +163,7 @@ void bch_btree_verify(struct btree *b, struct bset *new) } mutex_unlock(&b->c->verify_lock); + up(&b->io_mutex); } void bch_data_verify(struct cached_dev *dc, struct bio *bio) diff --git a/drivers/md/bcache/journal.c b/drivers/md/bcache/journal.c index ad687285c2df..9d32d5790822 100644 --- a/drivers/md/bcache/journal.c +++ b/drivers/md/bcache/journal.c @@ -564,6 +564,14 @@ static void journal_write_done(struct closure *cl) continue_at_nobarrier(cl, journal_write, system_wq); } +static void journal_write_unlock(struct closure *cl) +{ + struct cache_set *c = container_of(cl, struct cache_set, journal.io); + + c->journal.io_in_flight = 0; + spin_unlock(&c->journal.lock); +} + static void journal_write_unlocked(struct closure *cl) __releases(c->journal.lock) { @@ -578,15 +586,7 @@ static void journal_write_unlocked(struct closure *cl) bio_list_init(&list); if (!w->need_write) { - /* - * XXX: have to unlock closure before we unlock journal lock, - * else we race with bch_journal(). But this way we race - * against cache set unregister. Doh. - */ - set_closure_fn(cl, NULL, NULL); - closure_sub(cl, CLOSURE_RUNNING + 1); - spin_unlock(&c->journal.lock); - return; + closure_return_with_destructor(cl, journal_write_unlock); } else if (journal_full(&c->journal)) { journal_reclaim(c); spin_unlock(&c->journal.lock); @@ -662,10 +662,12 @@ static void journal_try_write(struct cache_set *c) w->need_write = true; - if (closure_trylock(cl, &c->cl)) - journal_write_unlocked(cl); - else + if (!c->journal.io_in_flight) { + c->journal.io_in_flight = 1; + closure_call(cl, journal_write_unlocked, NULL, &c->cl); + } else { spin_unlock(&c->journal.lock); + } } static struct journal_write *journal_wait_for_write(struct cache_set *c, @@ -793,7 +795,6 @@ int bch_journal_alloc(struct cache_set *c) { struct journal *j = &c->journal; - closure_init_unlocked(&j->io); spin_lock_init(&j->lock); INIT_DELAYED_WORK(&j->work, journal_write_work); diff --git a/drivers/md/bcache/journal.h b/drivers/md/bcache/journal.h index a6472fda94b2..9180c4465075 100644 --- a/drivers/md/bcache/journal.h +++ b/drivers/md/bcache/journal.h @@ -104,6 +104,7 @@ struct journal { /* used when waiting because the journal was full */ struct closure_waitlist wait; struct closure io; + int io_in_flight; struct delayed_work work; /* Number of blocks free in the bucket(s) we're currently writing to */ diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 93d593f957f6..b057676fc67d 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -225,7 +225,7 @@ static void write_bdev_super_endio(struct bio *bio, int error) struct cached_dev *dc = bio->bi_private; /* XXX: error checking */ - closure_put(&dc->sb_write.cl); + closure_put(&dc->sb_write); } static void __write_super(struct cache_sb *sb, struct bio *bio) @@ -263,12 +263,20 @@ static void __write_super(struct cache_sb *sb, struct bio *bio) submit_bio(REQ_WRITE, bio); } +static void bch_write_bdev_super_unlock(struct closure *cl) +{ + struct cached_dev *dc = container_of(cl, struct cached_dev, sb_write); + + up(&dc->sb_write_mutex); +} + void bch_write_bdev_super(struct cached_dev *dc, struct closure *parent) { - struct closure *cl = &dc->sb_write.cl; + struct closure *cl = &dc->sb_write; struct bio *bio = &dc->sb_bio; - closure_lock(&dc->sb_write, parent); + down(&dc->sb_write_mutex); + closure_init(cl, parent); bio_reset(bio); bio->bi_bdev = dc->bdev; @@ -278,7 +286,7 @@ void bch_write_bdev_super(struct cached_dev *dc, struct closure *parent) closure_get(cl); __write_super(&dc->sb, bio); - closure_return(cl); + closure_return_with_destructor(cl, bch_write_bdev_super_unlock); } static void write_super_endio(struct bio *bio, int error) @@ -286,16 +294,24 @@ static void write_super_endio(struct bio *bio, int error) struct cache *ca = bio->bi_private; bch_count_io_errors(ca, error, "writing superblock"); - closure_put(&ca->set->sb_write.cl); + closure_put(&ca->set->sb_write); +} + +static void bcache_write_super_unlock(struct closure *cl) +{ + struct cache_set *c = container_of(cl, struct cache_set, sb_write); + + up(&c->sb_write_mutex); } void bcache_write_super(struct cache_set *c) { - struct closure *cl = &c->sb_write.cl; + struct closure *cl = &c->sb_write; struct cache *ca; unsigned i; - closure_lock(&c->sb_write, &c->cl); + down(&c->sb_write_mutex); + closure_init(cl, &c->cl); c->sb.seq++; @@ -317,7 +333,7 @@ void bcache_write_super(struct cache_set *c) __write_super(&ca->sb, bio); } - closure_return(cl); + closure_return_with_destructor(cl, bcache_write_super_unlock); } /* UUID io */ @@ -325,23 +341,31 @@ void bcache_write_super(struct cache_set *c) static void uuid_endio(struct bio *bio, int error) { struct closure *cl = bio->bi_private; - struct cache_set *c = container_of(cl, struct cache_set, uuid_write.cl); + struct cache_set *c = container_of(cl, struct cache_set, uuid_write); cache_set_err_on(error, c, "accessing uuids"); bch_bbio_free(bio, c); closure_put(cl); } +static void uuid_io_unlock(struct closure *cl) +{ + struct cache_set *c = container_of(cl, struct cache_set, uuid_write); + + up(&c->uuid_write_mutex); +} + static void uuid_io(struct cache_set *c, unsigned long rw, struct bkey *k, struct closure *parent) { - struct closure *cl = &c->uuid_write.cl; + struct closure *cl = &c->uuid_write; struct uuid_entry *u; unsigned i; char buf[80]; BUG_ON(!parent); - closure_lock(&c->uuid_write, parent); + down(&c->uuid_write_mutex); + closure_init(cl, parent); for (i = 0; i < KEY_PTRS(k); i++) { struct bio *bio = bch_bbio_alloc(c); @@ -368,7 +392,7 @@ static void uuid_io(struct cache_set *c, unsigned long rw, u - c->uuids, u->uuid, u->label, u->first_reg, u->last_reg, u->invalidated); - closure_return(cl); + closure_return_with_destructor(cl, uuid_io_unlock); } static char *uuid_read(struct cache_set *c, struct jset *j, struct closure *cl) @@ -1098,7 +1122,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned block_size) set_closure_fn(&dc->disk.cl, cached_dev_flush, system_wq); kobject_init(&dc->disk.kobj, &bch_cached_dev_ktype); INIT_WORK(&dc->detach, cached_dev_detach_finish); - closure_init_unlocked(&dc->sb_write); + sema_init(&dc->sb_write_mutex, 1); INIT_LIST_HEAD(&dc->io_lru); spin_lock_init(&dc->io_lock); bch_cache_accounting_init(&dc->accounting, &dc->disk.cl); @@ -1454,11 +1478,11 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb) c->sort_crit_factor = int_sqrt(c->btree_pages); - closure_init_unlocked(&c->sb_write); + sema_init(&c->sb_write_mutex, 1); mutex_init(&c->bucket_lock); init_waitqueue_head(&c->try_wait); init_waitqueue_head(&c->bucket_wait); - closure_init_unlocked(&c->uuid_write); + sema_init(&c->uuid_write_mutex, 1); mutex_init(&c->sort_lock); spin_lock_init(&c->sort_time.lock);