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| author | Kent Overstreet <kent.overstreet@gmail.com> | 2022-02-26 21:46:41 -0500 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2023-10-22 17:09:26 -0400 |
| commit | 82732ef510b8455bbf9e9292b6fd04cb724bdadf (patch) | |
| tree | 9cbbade3d4d095cd0ac0573bbfae47cc29dc0b78 /fs/bcachefs/btree_io.c | |
| parent | 39dcace83889f43d5619d07c2ec76c286c88a85b (diff) | |
| download | lwn-82732ef510b8455bbf9e9292b6fd04cb724bdadf.tar.gz lwn-82732ef510b8455bbf9e9292b6fd04cb724bdadf.zip | |
bcachefs: Improve btree_node_write_if_need()
btree_node_write_if_need() kicks off a btree node write only if
need_write is set; this makes the locking easier to reason about by
moving the check into the cmpxchg loop in __bch2_btree_node_write().
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Diffstat (limited to 'fs/bcachefs/btree_io.c')
| -rw-r--r-- | fs/bcachefs/btree_io.c | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c index f4d6a6c5096d..540bfe07c128 100644 --- a/fs/bcachefs/btree_io.c +++ b/fs/bcachefs/btree_io.c @@ -471,7 +471,7 @@ void bch2_btree_init_next(struct btree_trans *trans, struct btree *b) }; if (log_u64s[1] >= (log_u64s[0] + log_u64s[2]) / 2) { - bch2_btree_node_write(c, b, SIX_LOCK_write); + bch2_btree_node_write(c, b, SIX_LOCK_write, 0); reinit_iter = true; } } @@ -1620,7 +1620,7 @@ static void __btree_node_write_done(struct bch_fs *c, struct btree *b) } while ((v = cmpxchg(&b->flags, old, new)) != old); if (new & (1U << BTREE_NODE_write_in_flight)) - __bch2_btree_node_write(c, b, true); + __bch2_btree_node_write(c, b, BTREE_WRITE_ALREADY_STARTED); } static void btree_node_write_done(struct bch_fs *c, struct btree *b) @@ -1741,7 +1741,7 @@ static void btree_write_submit(struct work_struct *work) bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree, &tmp.k); } -void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_started) +void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, unsigned flags) { struct btree_write_bio *wbio; struct bset_tree *t; @@ -1758,7 +1758,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_sta void *data; int ret; - if (already_started) + if (flags & BTREE_WRITE_ALREADY_STARTED) goto do_write; /* @@ -1774,13 +1774,18 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b, bool already_sta if (!(old & (1 << BTREE_NODE_dirty))) return; + if ((flags & BTREE_WRITE_ONLY_IF_NEED) && + !(old & (1 << BTREE_NODE_need_write))) + return; + if (!btree_node_may_write(b)) return; if (old & (1 << BTREE_NODE_never_write)) return; - BUG_ON(old & (1 << BTREE_NODE_write_in_flight)); + if (old & (1 << BTREE_NODE_write_in_flight)) + return; new &= ~(1 << BTREE_NODE_dirty); new &= ~(1 << BTREE_NODE_need_write); @@ -2044,12 +2049,13 @@ bool bch2_btree_post_write_cleanup(struct bch_fs *c, struct btree *b) * Use this one if the node is intent locked: */ void bch2_btree_node_write(struct bch_fs *c, struct btree *b, - enum six_lock_type lock_type_held) + enum six_lock_type lock_type_held, + unsigned flags) { if (lock_type_held == SIX_LOCK_intent || (lock_type_held == SIX_LOCK_read && six_lock_tryupgrade(&b->c.lock))) { - __bch2_btree_node_write(c, b, false); + __bch2_btree_node_write(c, b, flags); /* don't cycle lock unnecessarily: */ if (btree_node_just_written(b) && @@ -2061,7 +2067,7 @@ void bch2_btree_node_write(struct bch_fs *c, struct btree *b, if (lock_type_held == SIX_LOCK_read) six_lock_downgrade(&b->c.lock); } else { - __bch2_btree_node_write(c, b, false); + __bch2_btree_node_write(c, b, flags); if (lock_type_held == SIX_LOCK_write && btree_node_just_written(b)) bch2_btree_post_write_cleanup(c, b); |