bcachefs: Punt btree writes to workqueue to submit

We don't want to be submitting IO with btree locks held, and btree
writes usually aren't latency sensitive.

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/btree_io.c b/fs/bcachefs/btree_io.c
index fd90e434c78c51a4e8538e9f807b2a0c977ece38..2f5b7c629a9ceb01fb1f9c238b9abf1081abd390 100644 (file)
--- a/fs/bcachefs/btree_io.c
+++ b/fs/bcachefs/btree_io.c
@@ -1340,6 +1340,13 @@ static int validate_bset_for_write(struct bch_fs *c, struct btree *b,
        return ret;
 }
 
+static void btree_write_submit(struct work_struct *work)
+{
+       struct btree_write_bio *wbio = container_of(work, struct btree_write_bio, work);
+
+       bch2_submit_wbio_replicas(&wbio->wbio, wbio->wbio.c, BCH_DATA_btree, &wbio->key);
+}
+
 void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
 {
        struct btree_write_bio *wbio;
@@ -1347,7 +1354,6 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
        struct bset *i;
        struct btree_node *bn = NULL;
        struct btree_node_entry *bne = NULL;
-       struct bkey_buf k;
        struct bch_extent_ptr *ptr;
        struct sort_iter sort_iter;
        struct nonce nonce;
@@ -1358,8 +1364,6 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
        bool validate_before_checksum = false;
        void *data;
 
-       bch2_bkey_buf_init(&k);
-
        if (test_bit(BCH_FS_HOLD_BTREE_WRITES, &c->flags))
                return;
 
@@ -1538,6 +1542,7 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
        wbio_init(&wbio->wbio.bio);
        wbio->data                      = data;
        wbio->bytes                     = bytes;
+       wbio->wbio.c                    = c;
        wbio->wbio.used_mempool         = used_mempool;
        wbio->wbio.bio.bi_end_io        = btree_node_write_endio;
        wbio->wbio.bio.bi_private       = b;
@@ -1559,9 +1564,9 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
         * just make all btree node writes FUA to keep things sane.
         */
 
-       bch2_bkey_buf_copy(&k, c, &b->key);
+       bkey_copy(&wbio->key, &b->key);
 
-       bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(k.k)), ptr)
+       bkey_for_each_ptr(bch2_bkey_ptrs(bkey_i_to_s(&wbio->key)), ptr)
                ptr->offset += b->written;
 
        b->written += sectors_to_write;
@@ -1569,9 +1574,8 @@ void __bch2_btree_node_write(struct bch_fs *c, struct btree *b)
        atomic64_inc(&c->btree_writes_nr);
        atomic64_add(sectors_to_write, &c->btree_writes_sectors);
 
-       /* XXX: submitting IO with btree locks held: */
-       bch2_submit_wbio_replicas(&wbio->wbio, c, BCH_DATA_btree, k.k);
-       bch2_bkey_buf_exit(&k, c);
+       INIT_WORK(&wbio->work, btree_write_submit);
+       schedule_work(&wbio->work);
        return;
 err:
        set_btree_node_noevict(b);

diff --git a/fs/bcachefs/btree_io.h b/fs/bcachefs/btree_io.h
index 95c351611045a861cf9d90f87d860883df2b6dbd..c8a8b05a19b0f1b1bc74fe254e28facd6a98b4a6 100644 (file)
--- a/fs/bcachefs/btree_io.h
+++ b/fs/bcachefs/btree_io.h
@@ -42,6 +42,7 @@ struct btree_read_bio {
 
 struct btree_write_bio {
        struct work_struct      work;
+       __BKEY_PADDED(key, BKEY_BTREE_PTR_VAL_U64s_MAX);
        void                    *data;
        unsigned                bytes;
        struct bch_write_bio    wbio;