From 5db95e50e11bdd0a191a22fdbc1e68ec900aff89 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Wed, 28 Apr 2021 23:52:19 -0400 Subject: [PATCH] bcachefs: Re-implement extent merging in transaction commit path We haven't had extent merging in quite some time. It used to be done by the btree code when sorting btree nodes, but that was eliminated as part of the work to separate extent handling from core btree code. This patch re-implements extent merging in the transaction commit path. We don't currently have the ability to merge reflink pointers, we need to do some work on the triggers code to be able to do that without ending up with incorrect refcounts. Signed-off-by: Kent Overstreet --- fs/bcachefs/bkey_methods.c | 6 ++++- fs/bcachefs/bkey_methods.h | 5 +--- fs/bcachefs/btree_update_leaf.c | 41 ++++++++++++++++++++++++++++++++- 3 files changed, 46 insertions(+), 6 deletions(-) diff --git a/fs/bcachefs/bkey_methods.c b/fs/bcachefs/bkey_methods.c index ff9d770aabea..1ad6a9d30bb5 100644 --- a/fs/bcachefs/bkey_methods.c +++ b/fs/bcachefs/bkey_methods.c @@ -296,7 +296,11 @@ bool bch2_bkey_merge(struct bch_fs *c, struct bkey_s l, struct bkey_s_c r) { const struct bkey_ops *ops = &bch2_bkey_ops[l.k->type]; - return bch2_bkey_maybe_mergable(l.k, r.k) && ops->key_merge(c, l, r); + return bch2_bkey_maybe_mergable(l.k, r.k) && + (u64) l.k->size + r.k->size <= KEY_SIZE_MAX && + bch2_bkey_ops[l.k->type].key_merge && + !bch2_key_merging_disabled && + ops->key_merge(c, l, r); } static const struct old_bkey_type { diff --git a/fs/bcachefs/bkey_methods.h b/fs/bcachefs/bkey_methods.h index 3012035db1a3..4e316c2f6954 100644 --- a/fs/bcachefs/bkey_methods.h +++ b/fs/bcachefs/bkey_methods.h @@ -51,10 +51,7 @@ static inline bool bch2_bkey_maybe_mergable(const struct bkey *l, const struct b { return l->type == r->type && !bversion_cmp(l->version, r->version) && - !bpos_cmp(l->p, bkey_start_pos(r)) && - (u64) l->size + r->size <= KEY_SIZE_MAX && - bch2_bkey_ops[l->type].key_merge && - !bch2_key_merging_disabled; + !bpos_cmp(l->p, bkey_start_pos(r)); } bool bch2_bkey_merge(struct bch_fs *, struct bkey_s, struct bkey_s_c); diff --git a/fs/bcachefs/btree_update_leaf.c b/fs/bcachefs/btree_update_leaf.c index 1c12a11e45f7..4040771d645b 100644 --- a/fs/bcachefs/btree_update_leaf.c +++ b/fs/bcachefs/btree_update_leaf.c @@ -797,9 +797,38 @@ static int __btree_delete_at(struct btree_trans *trans, enum btree_id btree_id, return 0; } +static noinline int extent_front_merge(struct btree_trans *trans, + struct bkey_s_c k, + struct btree_insert_entry *i) +{ + struct bch_fs *c = trans->c; + struct bpos l_pos = k.k->p; + struct bkey_i *update; + int ret; + + update = bch2_trans_kmalloc(trans, bkey_bytes(k.k)); + ret = PTR_ERR_OR_ZERO(update); + if (ret) + return ret; + + bkey_reassemble(update, k); + + if (bch2_bkey_merge(c, bkey_i_to_s(update), bkey_i_to_s_c(i->k))) { + ret = __btree_delete_at(trans, i->btree_id, l_pos, + i->trigger_flags); + if (ret) + return ret; + + i->k = update; + } + + return 0; +} + static int extent_handle_overwrites(struct btree_trans *trans, struct btree_insert_entry *i) { + struct bch_fs *c = trans->c; struct btree_iter *iter, *update_iter; struct bpos start = bkey_start_pos(&i->k->k); struct bkey_i *update; @@ -814,8 +843,15 @@ static int extent_handle_overwrites(struct btree_trans *trans, if (!k.k || (ret = bkey_err(k))) goto out; - if (!bkey_cmp(k.k->p, bkey_start_pos(&i->k->k))) + if (!bkey_cmp(k.k->p, bkey_start_pos(&i->k->k))) { + if (bch2_bkey_maybe_mergable(k.k, &i->k->k)) { + ret = extent_front_merge(trans, k, i); + if (ret) + goto out; + } + goto next; + } while (bkey_cmp(i->k->k.p, bkey_start_pos(k.k)) > 0) { if (bkey_cmp(bkey_start_pos(k.k), start) < 0) { @@ -862,6 +898,9 @@ next: if (!k.k || (ret = bkey_err(k))) goto out; } + + if (bch2_bkey_maybe_mergable(&i->k->k, k.k)) + bch2_bkey_merge(c, bkey_i_to_s(i->k), k); out: bch2_trans_iter_put(trans, iter);