bcachefs: Seralize btree_update operations at btree_update_nodes_written()

Prep work for journalling updates to interior nodes - enforcing ordering
will greatly simplify those changes.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
This commit is contained in:
Kent Overstreet 2020-02-08 16:39:37 -05:00 committed by Kent Overstreet
parent 548b3d209f
commit ac7c51b218
4 changed files with 29 additions and 6 deletions

View file

@ -610,6 +610,7 @@ struct bch_fs {
mempool_t btree_interior_update_pool;
struct list_head btree_interior_update_list;
struct list_head btree_interior_updates_unwritten;
struct mutex btree_interior_update_lock;
struct closure_waitlist btree_interior_update_wait;

View file

@ -666,9 +666,15 @@ static void btree_update_nodes_written(struct closure *cl)
* to child nodes that weren't written yet: now, the child nodes have
* been written so we can write out the update to the interior node.
*/
retry:
mutex_lock(&c->btree_interior_update_lock);
as->nodes_written = true;
retry:
as = list_first_entry_or_null(&c->btree_interior_updates_unwritten,
struct btree_update, unwritten_list);
if (!as || !as->nodes_written) {
mutex_unlock(&c->btree_interior_update_lock);
return;
}
switch (as->mode) {
case BTREE_INTERIOR_NO_UPDATE:
@ -681,11 +687,12 @@ static void btree_update_nodes_written(struct closure *cl)
mutex_unlock(&c->btree_interior_update_lock);
btree_node_lock_type(c, b, SIX_LOCK_read);
six_unlock_read(&b->c.lock);
mutex_lock(&c->btree_interior_update_lock);
goto retry;
}
BUG_ON(!btree_node_dirty(b));
closure_wait(&btree_current_write(b)->wait, cl);
closure_wait(&btree_current_write(b)->wait, &as->cl);
list_del(&as->write_blocked_list);
@ -694,6 +701,8 @@ static void btree_update_nodes_written(struct closure *cl)
* nodes to be writeable:
*/
closure_wake_up(&c->btree_interior_update_wait);
list_del(&as->unwritten_list);
mutex_unlock(&c->btree_interior_update_lock);
/*
@ -702,6 +711,7 @@ static void btree_update_nodes_written(struct closure *cl)
*/
bch2_btree_node_write_cond(c, b, true);
six_unlock_read(&b->c.lock);
continue_at(&as->cl, btree_update_nodes_reachable, system_wq);
break;
case BTREE_INTERIOR_UPDATING_AS:
@ -716,8 +726,12 @@ static void btree_update_nodes_written(struct closure *cl)
/*
* and then we have to wait on that btree_update to finish:
*/
closure_wait(&as->parent_as->wait, cl);
closure_wait(&as->parent_as->wait, &as->cl);
list_del(&as->unwritten_list);
mutex_unlock(&c->btree_interior_update_lock);
continue_at(&as->cl, btree_update_nodes_reachable, system_wq);
break;
case BTREE_INTERIOR_UPDATING_ROOT:
@ -728,6 +742,7 @@ static void btree_update_nodes_written(struct closure *cl)
mutex_unlock(&c->btree_interior_update_lock);
btree_node_lock_type(c, b, SIX_LOCK_read);
six_unlock_read(&b->c.lock);
mutex_lock(&c->btree_interior_update_lock);
goto retry;
}
@ -744,6 +759,8 @@ static void btree_update_nodes_written(struct closure *cl)
* can reuse the old nodes it'll have to do a journal commit:
*/
six_unlock_read(&b->c.lock);
list_del(&as->unwritten_list);
mutex_unlock(&c->btree_interior_update_lock);
/*
@ -762,11 +779,12 @@ static void btree_update_nodes_written(struct closure *cl)
as->journal_seq = bch2_journal_last_unwritten_seq(&c->journal);
btree_update_wait_on_journal(cl);
return;
btree_update_wait_on_journal(&as->cl);
break;
}
continue_at(cl, btree_update_nodes_reachable, system_wq);
mutex_lock(&c->btree_interior_update_lock);
goto retry;
}
/*
@ -778,6 +796,7 @@ static void btree_update_updated_node(struct btree_update *as, struct btree *b)
struct bch_fs *c = as->c;
mutex_lock(&c->btree_interior_update_lock);
list_add_tail(&as->unwritten_list, &c->btree_interior_updates_unwritten);
BUG_ON(as->mode != BTREE_INTERIOR_NO_UPDATE);
BUG_ON(!btree_node_dirty(b));
@ -858,6 +877,7 @@ static void btree_update_updated_root(struct btree_update *as)
struct btree_root *r = &c->btree_roots[as->btree_id];
mutex_lock(&c->btree_interior_update_lock);
list_add_tail(&as->unwritten_list, &c->btree_interior_updates_unwritten);
BUG_ON(as->mode != BTREE_INTERIOR_NO_UPDATE);

View file

@ -55,6 +55,7 @@ struct btree_update {
struct bch_fs *c;
struct list_head list;
struct list_head unwritten_list;
/* What kind of update are we doing? */
enum {

View file

@ -642,6 +642,7 @@ static struct bch_fs *bch2_fs_alloc(struct bch_sb *sb, struct bch_opts opts)
INIT_LIST_HEAD(&c->list);
INIT_LIST_HEAD(&c->btree_interior_update_list);
INIT_LIST_HEAD(&c->btree_interior_updates_unwritten);
mutex_init(&c->btree_reserve_cache_lock);
mutex_init(&c->btree_interior_update_lock);