bcachefs: Ensure btree node cache is not more than half dirty

Tweak journal reclaim to ensure the btree node cache isn't more
than half dirty so that memory reclaim can always make progress - the
same as we do for the btree key cache.

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

diff --git a/fs/bcachefs/journal_reclaim.c b/fs/bcachefs/journal_reclaim.c
index e8b7ed8e1333674c3a1f3cb30f6e624138bd7781..0f3c103e63ee1cf54bb7e263efe83a8b994050ce 100644 (file)
--- a/fs/bcachefs/journal_reclaim.c
+++ b/fs/bcachefs/journal_reclaim.c
@@ -640,6 +640,9 @@ static int __bch2_journal_reclaim(struct journal *j, bool direct, bool kicked)
                if (fifo_free(&j->pin) <= 32)
                        min_nr = 1;
 
+               if (atomic_read(&c->btree_cache.dirty) * 2 > c->btree_cache.used)
+                       min_nr = 1;
+
                min_key_cache = min(bch2_nr_btree_keys_need_flush(c), (size_t) 128);
 
                trace_and_count(c, journal_reclaim_start, c,