bcachefs: Add iter->idx

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

diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index 34d4ce32c2a23d6334c5dcdbaf851da33c9360ce..fef5b04440b3a0de22cfbcc14e627fcc43c332d7 100644 (file)
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -1606,24 +1606,12 @@ static inline void bch2_btree_iter_init(struct btree_trans *trans,
 
 /* new transactional stuff: */
 
-static inline unsigned btree_trans_iter_idx(struct btree_trans *trans,
-                                           struct btree_iter *iter)
-{
-       ssize_t idx = iter - trans->iters;
-
-       EBUG_ON(idx < 0 || idx >= trans->nr_iters);
-       EBUG_ON(!(trans->iters_linked & (1ULL << idx)));
-
-       return idx;
-}
-
 int bch2_trans_iter_put(struct btree_trans *trans,
                        struct btree_iter *iter)
 {
-       ssize_t idx = btree_trans_iter_idx(trans, iter);
        int ret = btree_iter_err(iter);
 
-       trans->iters_live       &= ~(1ULL << idx);
+       trans->iters_live       &= ~(1ULL << iter->idx);
        return ret;
 }
 
@@ -1643,7 +1631,7 @@ int bch2_trans_iter_free(struct btree_trans *trans,
 {
        int ret = btree_iter_err(iter);
 
-       __bch2_trans_iter_free(trans, btree_trans_iter_idx(trans, iter));
+       __bch2_trans_iter_free(trans, iter->idx);
        return ret;
 }
 
@@ -1652,8 +1640,7 @@ int bch2_trans_iter_free_on_commit(struct btree_trans *trans,
 {
        int ret = btree_iter_err(iter);
 
-       trans->iters_unlink_on_commit |=
-               1ULL << btree_trans_iter_idx(trans, iter);
+       trans->iters_unlink_on_commit |= 1ULL << iter->idx;
        return ret;
 }
 
@@ -1729,6 +1716,8 @@ static int btree_trans_iter_alloc(struct btree_trans *trans)
 
        idx = trans->nr_iters++;
        BUG_ON(trans->nr_iters > trans->size);
+
+       trans->iters[idx].idx = idx;
 got_slot:
        BUG_ON(trans->iters_linked & (1ULL << idx));
        trans->iters_linked |= 1ULL << idx;
@@ -1826,6 +1815,7 @@ struct btree_iter *bch2_trans_copy_iter(struct btree_trans *trans,
                                        struct btree_iter *src)
 {
        struct btree_iter *iter;
+       unsigned offset = offsetof(struct btree_iter, trans);
        int i, idx;
 
        idx = btree_trans_iter_alloc(trans);
@@ -1837,7 +1827,10 @@ struct btree_iter *bch2_trans_copy_iter(struct btree_trans *trans,
        trans->iters_unlink_on_restart  |= 1ULL << idx;
 
        iter = &trans->iters[idx];
-       *iter = *src;
+
+       memcpy((void *) iter + offset,
+              (void *)  src + offset,
+              sizeof(*iter) - offset);
 
        for (i = 0; i < BTREE_MAX_DEPTH; i++)
                if (btree_node_locked(iter, i))

diff --git a/fs/bcachefs/btree_iter.h b/fs/bcachefs/btree_iter.h
index 74eb5ed12ca0ca1f08d0cff67faeed2979b99b2e..800320966ff14c382fa300fec05ec4f12eed4336 100644 (file)
--- a/fs/bcachefs/btree_iter.h
+++ b/fs/bcachefs/btree_iter.h
@@ -36,15 +36,11 @@ static inline int btree_iter_err(const struct btree_iter *iter)
 /* Iterate over iters within a transaction: */
 
 static inline struct btree_iter *
-__trans_next_iter(struct btree_trans *trans, struct btree_iter *iter)
+__trans_next_iter(struct btree_trans *trans, unsigned idx)
 {
-       unsigned idx;
+       EBUG_ON(idx < trans->nr_iters && trans->iters[idx].idx != idx);
 
-       /* XXX expensive pointer subtraction: */
-
-       for (idx = iter - trans->iters;
-            idx < trans->nr_iters;
-            idx++)
+       for (; idx < trans->nr_iters; idx++)
                if (trans->iters_linked & (1ULL << idx))
                        return &trans->iters[idx];
 
@@ -52,9 +48,9 @@ __trans_next_iter(struct btree_trans *trans, struct btree_iter *iter)
 }
 
 #define trans_for_each_iter(_trans, _iter)                             \
-       for (_iter = (_trans)->iters;                                   \
-            (_iter = __trans_next_iter((_trans), _iter));              \
-            _iter++)
+       for (_iter = __trans_next_iter((_trans), 0);                    \
+            (_iter);                                                   \
+            _iter = __trans_next_iter((_trans), (_iter)->idx + 1))
 
 static inline bool __iter_has_node(const struct btree_iter *iter,
                                   const struct btree *b)
@@ -73,30 +69,23 @@ static inline bool __iter_has_node(const struct btree_iter *iter,
 
 static inline struct btree_iter *
 __trans_next_iter_with_node(struct btree_trans *trans, struct btree *b,
-                           struct btree_iter *iter)
+                           unsigned idx)
 {
-       unsigned idx;
-
-       /* XXX expensive pointer subtraction: */
-
-       for (idx = iter - trans->iters;
-            idx < trans->nr_iters;
-            idx++) {
-               if (!(trans->iters_linked & (1ULL << idx)))
-                       continue;
+       EBUG_ON(idx < trans->nr_iters && trans->iters[idx].idx != idx);
 
-               iter = &trans->iters[idx];
-               if (__iter_has_node(iter, b))
-                       return iter;
-       }
+       for (; idx < trans->nr_iters; idx++)
+               if ((trans->iters_linked & (1ULL << idx)) &&
+                   __iter_has_node(&trans->iters[idx], b))
+                       return &trans->iters[idx];
 
        return NULL;
 }
 
 #define trans_for_each_iter_with_node(_trans, _b, _iter)               \
-       for (_iter = (_trans)->iters;                                   \
-            (_iter = __trans_next_iter_with_node((_trans), (_b), _iter));\
-            _iter++)
+       for (_iter = __trans_next_iter_with_node((_trans), (_b), 0);    \
+            (_iter);                                                   \
+            _iter = __trans_next_iter_with_node((_trans), (_b),        \
+                                                (_iter)->idx + 1))
 
 #ifdef CONFIG_BCACHEFS_DEBUG
 void bch2_btree_iter_verify(struct btree_iter *, struct btree *);

diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h
index 7ef1feba28177fbf011b5cd42d33a7f3ec44b09d..bd6852d951ea437066a08ead4c443d8d9fd2d07f 100644 (file)
--- a/fs/bcachefs/btree_types.h
+++ b/fs/bcachefs/btree_types.h
@@ -210,6 +210,8 @@ enum btree_iter_uptodate {
  * @nodes_intent_locked        - bitmask indicating which locks are intent locks
  */
 struct btree_iter {
+       u8                      idx;
+
        struct btree_trans      *trans;
        struct bpos             pos;