bcachefs: more write buffer refactoring

prep work for big rewrite - no functional changes in this patch.

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

diff --git a/fs/bcachefs/btree_write_buffer.c b/fs/bcachefs/btree_write_buffer.c
index 9470d465718207e2a64c9c72c90c516dac5ecadd..6ab26576252c17edc603ad42438e7a9ebd9b4181 100644 (file)
--- a/fs/bcachefs/btree_write_buffer.c
+++ b/fs/bcachefs/btree_write_buffer.c
@@ -163,9 +163,6 @@ int bch2_btree_write_buffer_flush_locked(struct btree_trans *trans)
        keys = wb->keys[s.idx];
        nr = s.nr;
 
-       if (race_fault())
-               goto slowpath;
-
        /*
         * We first sort so that we can detect and skip redundant updates, and
         * then we attempt to flush in sorted btree order, as this is most
@@ -209,6 +206,11 @@ int bch2_btree_write_buffer_flush_locked(struct btree_trans *trans)
                iter.path->preserve = false;
 
                do {
+                       if (race_fault()) {
+                               ret = -BCH_ERR_journal_reclaim_would_deadlock;
+                               break;
+                       }
+
                        ret = wb_flush_one(trans, &iter, i, &write_locked, &fast);
                        if (!write_locked)
                                bch2_trans_begin(trans);
@@ -227,46 +229,45 @@ int bch2_btree_write_buffer_flush_locked(struct btree_trans *trans)
                bch2_btree_node_unlock_write(trans, iter.path, iter.path->l[0].b);
        bch2_trans_iter_exit(trans, &iter);
 
-       trace_write_buffer_flush(trans, nr, skipped, fast, wb->size);
-
-       if (slowpath)
-               goto slowpath;
-
+       if (ret)
+               goto err;
+
+       if (slowpath) {
+               /*
+                * Flush in the order they were present in the journal, so that
+                * we can release journal pins:
+                * The fastpath zapped the seq of keys that were successfully flushed so
+                * we can skip those here.
+                */
+               trace_and_count(c, write_buffer_flush_slowpath, trans, slowpath, nr);
+
+               sort(keys, nr, sizeof(keys[0]),
+                    btree_write_buffered_journal_cmp,
+                    NULL);
+
+               for (i = keys; i < keys + nr; i++) {
+                       if (!i->journal_seq)
+                               continue;
+
+                       bch2_journal_pin_update(j, i->journal_seq, &pin,
+                                     bch2_btree_write_buffer_journal_flush);
+
+                       ret = commit_do(trans, NULL, NULL,
+                                       BCH_WATERMARK_reclaim|
+                                       BCH_TRANS_COMMIT_no_check_rw|
+                                       BCH_TRANS_COMMIT_no_enospc|
+                                       BCH_TRANS_COMMIT_no_journal_res|
+                                       BCH_TRANS_COMMIT_journal_reclaim,
+                                       btree_write_buffered_insert(trans, i));
+                       if (ret)
+                               goto err;
+               }
+       }
+err:
        bch2_fs_fatal_err_on(ret, c, "%s: insert error %s", __func__, bch2_err_str(ret));
-out:
+       trace_write_buffer_flush(trans, nr, skipped, fast, wb->size);
        bch2_journal_pin_drop(j, &pin);
        return ret;
-slowpath:
-       trace_and_count(c, write_buffer_flush_slowpath, trans, slowpath, nr);
-
-       /*
-        * Now sort the rest by journal seq and bump the journal pin as we go.
-        * The slowpath zapped the seq of keys that were successfully flushed so
-        * we can skip those here.
-        */
-       sort(keys, nr, sizeof(keys[0]),
-            btree_write_buffered_journal_cmp,
-            NULL);
-
-       for (i = keys; i < keys + nr; i++) {
-               if (!i->journal_seq)
-                       continue;
-
-               bch2_journal_pin_update(j, i->journal_seq, &pin,
-                             bch2_btree_write_buffer_journal_flush);
-
-               ret = commit_do(trans, NULL, NULL,
-                               BCH_WATERMARK_reclaim|
-                               BCH_TRANS_COMMIT_no_check_rw|
-                               BCH_TRANS_COMMIT_no_enospc|
-                               BCH_TRANS_COMMIT_no_journal_res|
-                               BCH_TRANS_COMMIT_journal_reclaim,
-                               btree_write_buffered_insert(trans, i));
-               if (bch2_fs_fatal_err_on(ret, c, "%s: insert error %s", __func__, bch2_err_str(ret)))
-                       break;
-       }
-
-       goto out;
 }
 
 int bch2_btree_write_buffer_flush_sync(struct btree_trans *trans)