bcachefs: Stale ptr cleanup is now done by gc_gens

Before we had dedicated gc code for bucket->oldest_gen this was
btree_gc's responsibility, but now that we have that we can rip it out,
simplifying the already overcomplicated btree_gc.

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

diff --git a/fs/bcachefs/btree_gc.c b/fs/bcachefs/btree_gc.c
index d1fbe3b77379ae9202c33001d62d8a603468d917..ba22c36e30a1dc43e30ef0dac08084027363a6a3 100644 (file)
--- a/fs/bcachefs/btree_gc.c
+++ b/fs/bcachefs/btree_gc.c
@@ -726,11 +726,9 @@ fsck_err:
 static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
                            unsigned level, bool is_root,
                            struct bkey_s_c *k,
-                           u8 *max_stale, bool initial)
+                           bool initial)
 {
        struct bch_fs *c = trans->c;
-       struct bkey_ptrs_c ptrs;
-       const struct bch_extent_ptr *ptr;
        struct bkey deleted = KEY(0, 0, 0);
        struct bkey_s_c old = (struct bkey_s_c) { &deleted, NULL };
        unsigned flags =
@@ -755,17 +753,6 @@ static int bch2_gc_mark_key(struct btree_trans *trans, enum btree_id btree_id,
                        atomic64_set(&c->key_version, k->k->version.lo);
        }
 
-       ptrs = bch2_bkey_ptrs_c(*k);
-       bkey_for_each_ptr(ptrs, ptr) {
-               struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
-               struct bucket *g = PTR_GC_BUCKET(ca, ptr);
-
-               if (gen_after(g->oldest_gen, ptr->gen))
-                       g->oldest_gen = ptr->gen;
-
-               *max_stale = max(*max_stale, ptr_stale(ca, ptr));
-       }
-
        ret = bch2_mark_key(trans, old, *k, flags);
 fsck_err:
 err:
@@ -774,8 +761,7 @@ err:
        return ret;
 }
 
-static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, u8 *max_stale,
-                             bool initial)
+static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, bool initial)
 {
        struct bch_fs *c = trans->c;
        struct btree_node_iter iter;
@@ -784,8 +770,6 @@ static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, u8 *ma
        struct bkey_buf prev, cur;
        int ret = 0;
 
-       *max_stale = 0;
-
        if (!btree_node_type_needs_gc(btree_node_type(b)))
                return 0;
 
@@ -796,7 +780,7 @@ static int btree_gc_mark_node(struct btree_trans *trans, struct btree *b, u8 *ma
 
        while ((k = bch2_btree_node_iter_peek_unpack(&iter, b, &unpacked)).k) {
                ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, false,
-                                      &k, max_stale, initial);
+                                      &k, initial);
                if (ret)
                        break;
 
@@ -827,7 +811,6 @@ static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
                : bch2_expensive_debug_checks           ? 0
                : !btree_node_type_needs_gc(btree_id)   ? 1
                : 0;
-       u8 max_stale = 0;
        int ret = 0;
 
        gc_pos_set(c, gc_pos_btree(btree_id, POS_MIN, 0));
@@ -838,21 +821,9 @@ static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
 
                gc_pos_set(c, gc_pos_btree_node(b));
 
-               ret = btree_gc_mark_node(trans, b, &max_stale, initial);
+               ret = btree_gc_mark_node(trans, b, initial);
                if (ret)
                        break;
-
-               if (!initial) {
-                       if (max_stale > 64)
-                               bch2_btree_node_rewrite(trans, &iter, b,
-                                               BTREE_INSERT_NOWAIT|
-                                               BTREE_INSERT_GC_LOCK_HELD);
-                       else if (!bch2_btree_gc_rewrite_disabled &&
-                                (bch2_btree_gc_always_rewrite || max_stale > 16))
-                               bch2_btree_node_rewrite(trans, &iter,
-                                               b, BTREE_INSERT_NOWAIT|
-                                               BTREE_INSERT_GC_LOCK_HELD);
-               }
        }
        bch2_trans_iter_exit(trans, &iter);
 
@@ -864,8 +835,8 @@ static int bch2_gc_btree(struct btree_trans *trans, enum btree_id btree_id,
        if (!btree_node_fake(b)) {
                struct bkey_s_c k = bkey_i_to_s_c(&b->key);
 
-               ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, true,
-                                      &k, &max_stale, initial);
+               ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level,
+                                      true, &k, initial);
        }
        gc_pos_set(c, gc_pos_btree_root(b->c.btree_id));
        mutex_unlock(&c->btree_root_lock);
@@ -880,7 +851,6 @@ static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b
        struct btree_and_journal_iter iter;
        struct bkey_s_c k;
        struct bkey_buf cur, prev;
-       u8 max_stale = 0;
        char buf[200];
        int ret = 0;
 
@@ -893,8 +863,8 @@ static int bch2_gc_btree_init_recurse(struct btree_trans *trans, struct btree *b
                BUG_ON(bpos_cmp(k.k->p, b->data->min_key) < 0);
                BUG_ON(bpos_cmp(k.k->p, b->data->max_key) > 0);
 
-               ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, false,
-                                      &k, &max_stale, true);
+               ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level,
+                                      false, &k, true);
                if (ret) {
                        bch_err(c, "%s: error %i from bch2_gc_mark_key", __func__, ret);
                        goto fsck_err;
@@ -985,7 +955,6 @@ static int bch2_gc_btree_init(struct btree_trans *trans,
                : bch2_expensive_debug_checks           ? 0
                : !btree_node_type_needs_gc(btree_id)   ? 1
                : 0;
-       u8 max_stale = 0;
        char buf[100];
        int ret = 0;
 
@@ -1018,7 +987,7 @@ static int bch2_gc_btree_init(struct btree_trans *trans,
                struct bkey_s_c k = bkey_i_to_s_c(&b->key);
 
                ret = bch2_gc_mark_key(trans, b->c.btree_id, b->c.level, true,
-                                      &k, &max_stale, true);
+                                      &k, true);
        }
 fsck_err:
        six_unlock_read(&b->c.lock);
@@ -1313,7 +1282,6 @@ static int bch2_alloc_write_key(struct btree_trans *trans,
                .dev            = iter->pos.inode,
                .bucket         = iter->pos.offset,
                .gen            = g->mark.gen,
-               .oldest_gen     = g->oldest_gen,
                .data_type      = g->mark.data_type,
                .dirty_sectors  = g->mark.dirty_sectors,
                .cached_sectors = g->mark.cached_sectors,
@@ -1330,8 +1298,7 @@ static int bch2_alloc_write_key(struct btree_trans *trans,
            gc_u.data_type != BCH_DATA_btree)
                return 0;
 
-       if (!bkey_alloc_unpacked_cmp(old_u, gc_u) ||
-           gen_after(old_u.gen, gc_u.gen))
+       if (gen_after(old_u.gen, gc_u.gen))
                return 0;
 
 #define copy_bucket_field(_f)                                          \
@@ -1353,8 +1320,6 @@ static int bch2_alloc_write_key(struct btree_trans *trans,
        copy_bucket_field(stripe);
 #undef copy_bucket_field
 
-       new_u.oldest_gen = gc_u.oldest_gen;
-
        if (!bkey_alloc_unpacked_cmp(old_u, new_u))
                return 0;