From 69529e313666457c295ebb256f41126ca635b36b Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@gmail.com>
Date: Sun, 2 Jan 2022 18:40:44 -0500
Subject: [PATCH] Update bcachefs sources to 90d824456e bcachefs: Improve path
 for when btree_gc needs another pass

---
 .bcachefs_revision        |  2 +-
 libbcachefs/btree_gc.c    | 72 ++++++++++++++++++++++++++++++---------
 libbcachefs/k-eytzinger.h | 13 +++++++
 3 files changed, 69 insertions(+), 18 deletions(-)
 create mode 100644 libbcachefs/k-eytzinger.h

diff --git a/.bcachefs_revision b/.bcachefs_revision
index 193d8bd7..e9908fb6 100644
--- a/.bcachefs_revision
+++ b/.bcachefs_revision
@@ -1 +1 @@
-aa439f3b94eb3141f9b6d71f780300e7fef44af9
+90d824456e169e50965814b74a75c50045b13976
diff --git a/libbcachefs/btree_gc.c b/libbcachefs/btree_gc.c
index 101cef7e..0625a65d 100644
--- a/libbcachefs/btree_gc.c
+++ b/libbcachefs/btree_gc.c
@@ -586,7 +586,7 @@ static int bch2_check_fix_ptrs(struct bch_fs *c, enum btree_id btree_id,
 				(bch2_bkey_val_to_text(&PBUF(buf), c, *k), buf))) {
 			if (data_type == BCH_DATA_btree) {
 				g->_mark.data_type	= data_type;
-				g->gen_valid		= true;
+				set_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
 			} else {
 				do_update = true;
 			}
@@ -1425,6 +1425,27 @@ static int bch2_gc_alloc_start(struct bch_fs *c, bool initial, bool metadata_onl
 	return bch2_alloc_read(c, true, metadata_only);
 }
 
+static void bch2_gc_alloc_reset(struct bch_fs *c, bool initial, bool metadata_only)
+{
+	struct bch_dev *ca;
+	unsigned i;
+
+	for_each_member_device(ca, c, i) {
+		struct bucket_array *buckets = __bucket_array(ca, true);
+		struct bucket *g;
+
+		for_each_bucket(g, buckets) {
+			if (metadata_only &&
+			    (g->mark.data_type == BCH_DATA_user ||
+			     g->mark.data_type == BCH_DATA_cached ||
+			     g->mark.data_type == BCH_DATA_parity))
+				continue;
+			g->_mark.dirty_sectors = 0;
+			g->_mark.cached_sectors = 0;
+		}
+	};
+}
+
 static int bch2_gc_reflink_done(struct bch_fs *c, bool initial,
 				bool metadata_only)
 {
@@ -1495,6 +1516,16 @@ fsck_err:
 	return ret;
 }
 
+static void bch2_gc_reflink_reset(struct bch_fs *c, bool initial,
+				  bool metadata_only)
+{
+	struct genradix_iter iter;
+	struct reflink_gc *r;
+
+	genradix_for_each(&c->reflink_gc_table, iter, r)
+		r->refcount = 0;
+}
+
 static int bch2_gc_reflink_start(struct bch_fs *c, bool initial,
 				 bool metadata_only)
 {
@@ -1597,6 +1628,12 @@ fsck_err:
 	return ret;
 }
 
+static void bch2_gc_stripes_reset(struct bch_fs *c, bool initial,
+				bool metadata_only)
+{
+	genradix_free(&c->gc_stripes);
+}
+
 /**
  * bch2_gc - walk _all_ references to buckets, and recompute them:
  *
@@ -1630,13 +1667,13 @@ int bch2_gc(struct bch_fs *c, bool initial, bool metadata_only)
 	/* flush interior btree updates: */
 	closure_wait_event(&c->btree_interior_update_wait,
 			   !bch2_btree_interior_updates_nr_pending(c));
-again:
+
 	ret   = bch2_gc_start(c, metadata_only) ?:
 		bch2_gc_alloc_start(c, initial, metadata_only) ?:
 		bch2_gc_reflink_start(c, initial, metadata_only);
 	if (ret)
 		goto out;
-
+again:
 	gc_pos_set(c, gc_phase(GC_PHASE_START));
 
 	bch2_mark_superblocks(c);
@@ -1675,25 +1712,26 @@ again:
 
 	if (test_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags) ||
 	    (!iter && bch2_test_restart_gc)) {
+		if (iter++ > 2) {
+			bch_info(c, "Unable to fix bucket gens, looping");
+			ret = -EINVAL;
+			goto out;
+		}
+
 		/*
 		 * XXX: make sure gens we fixed got saved
 		 */
-		if (iter++ <= 2) {
-			bch_info(c, "Second GC pass needed, restarting:");
-			clear_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
-			__gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
+		bch_info(c, "Second GC pass needed, restarting:");
+		clear_bit(BCH_FS_NEED_ANOTHER_GC, &c->flags);
+		__gc_pos_set(c, gc_phase(GC_PHASE_NOT_RUNNING));
 
-			percpu_down_write(&c->mark_lock);
-			bch2_gc_free(c);
-			percpu_up_write(&c->mark_lock);
-			/* flush fsck errors, reset counters */
-			bch2_flush_fsck_errs(c);
+		bch2_gc_stripes_reset(c, initial, metadata_only);
+		bch2_gc_alloc_reset(c, initial, metadata_only);
+		bch2_gc_reflink_reset(c, initial, metadata_only);
 
-			goto again;
-		}
-
-		bch_info(c, "Unable to fix bucket gens, looping");
-		ret = -EINVAL;
+		/* flush fsck errors, reset counters */
+		bch2_flush_fsck_errs(c);
+		goto again;
 	}
 out:
 	if (!ret) {
diff --git a/libbcachefs/k-eytzinger.h b/libbcachefs/k-eytzinger.h
new file mode 100644
index 00000000..819db34e
--- /dev/null
+++ b/libbcachefs/k-eytzinger.h
@@ -0,0 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _K_EYTZINGER_H
+#define _K_EYTZINGER_H
+
+/* One based indexing */
+/* k = number of children */
+
+static inline unsigned k_eytzinger_child(unsigned k, unsigned i, unsigned child)
+{
+	return (k * i + child) * (k - 1);
+}
+
+#endif /* _K_EYTZINGER_H */