bcachefs: Optimize bch2_trans_iter_init()

When flags & btree_id are constants, we can constant fold the entire
calculation of the actual iterator flags - and the whole thing becomes
small enough to inline.

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

diff --git a/fs/bcachefs/btree_iter.c b/fs/bcachefs/btree_iter.c
index 331479f34a0cc978cd341dda2e92b50eac116c68..238ba10d34e42167e9f4abf0a0e260b66704120e 100644 (file)
--- a/fs/bcachefs/btree_iter.c
+++ b/fs/bcachefs/btree_iter.c
@@ -2623,68 +2623,22 @@ void bch2_trans_iter_exit(struct btree_trans *trans, struct btree_iter *iter)
        iter->key_cache_path = NULL;
 }
 
-static inline void __bch2_trans_iter_init(struct btree_trans *trans,
-                                         struct btree_iter *iter,
-                                         enum btree_id btree_id, struct bpos pos,
-                                         unsigned locks_want,
-                                         unsigned depth,
-                                         unsigned flags)
-{
-       if (unlikely(trans->restarted))
-               panic("bch2_trans_iter_init(): in transaction restart, %s by %pS\n",
-                     bch2_err_str(trans->restarted),
-                     (void *) trans->last_restarted_ip);
-
-       if (flags & BTREE_ITER_ALL_LEVELS)
-               flags |= BTREE_ITER_ALL_SNAPSHOTS|__BTREE_ITER_ALL_SNAPSHOTS;
-
-       if (!(flags & (BTREE_ITER_ALL_SNAPSHOTS|BTREE_ITER_NOT_EXTENTS)) &&
-           btree_node_type_is_extents(btree_id))
-               flags |= BTREE_ITER_IS_EXTENTS;
-
-       if (!(flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
-           !btree_type_has_snapshots(btree_id))
-               flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
-
-       if (!(flags & BTREE_ITER_ALL_SNAPSHOTS) &&
-           btree_type_has_snapshots(btree_id))
-               flags |= BTREE_ITER_FILTER_SNAPSHOTS;
-
-       if (trans->journal_replay_not_finished)
-               flags |= BTREE_ITER_WITH_JOURNAL;
-
-       iter->trans     = trans;
-       iter->path      = NULL;
-       iter->update_path = NULL;
-       iter->key_cache_path = NULL;
-       iter->btree_id  = btree_id;
-       iter->min_depth = depth;
-       iter->flags     = flags;
-       iter->snapshot  = pos.snapshot;
-       iter->pos       = pos;
-       iter->k.type    = KEY_TYPE_deleted;
-       iter->k.p       = pos;
-       iter->k.size    = 0;
-       iter->journal_idx = 0;
-       iter->journal_pos = POS_MIN;
-
-       iter->path = bch2_path_get(trans, btree_id, iter->pos,
-                                  locks_want, depth, flags);
-}
-
-void bch2_trans_iter_init(struct btree_trans *trans,
+static inline void bch2_trans_iter_init_inlined(struct btree_trans *trans,
                          struct btree_iter *iter,
                          unsigned btree_id, struct bpos pos,
                          unsigned flags)
 {
-       if (!btree_id_cached(trans->c, btree_id)) {
-               flags &= ~BTREE_ITER_CACHED;
-               flags &= ~BTREE_ITER_WITH_KEY_CACHE;
-       } else if (!(flags & BTREE_ITER_CACHED))
-               flags |= BTREE_ITER_WITH_KEY_CACHE;
+       bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
+                              bch2_btree_iter_flags(trans, btree_id, flags));
+}
 
-       __bch2_trans_iter_init(trans, iter, btree_id, pos,
-                              0, 0, flags);
+void bch2_trans_iter_init_outlined(struct btree_trans *trans,
+                         struct btree_iter *iter,
+                         enum btree_id btree_id, struct bpos pos,
+                         unsigned flags)
+{
+       bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
+                              bch2_btree_iter_flags(trans, btree_id, flags));
 }
 
 void bch2_trans_node_iter_init(struct btree_trans *trans,
@@ -2695,11 +2649,15 @@ void bch2_trans_node_iter_init(struct btree_trans *trans,
                               unsigned depth,
                               unsigned flags)
 {
-       __bch2_trans_iter_init(trans, iter, btree_id, pos, locks_want, depth,
-                              BTREE_ITER_NOT_EXTENTS|
-                              __BTREE_ITER_ALL_SNAPSHOTS|
-                              BTREE_ITER_ALL_SNAPSHOTS|
-                              flags);
+       flags |= BTREE_ITER_NOT_EXTENTS;
+       flags |= __BTREE_ITER_ALL_SNAPSHOTS;
+       flags |= BTREE_ITER_ALL_SNAPSHOTS;
+
+       bch2_trans_iter_init_common(trans, iter, btree_id, pos, locks_want, depth,
+                              __bch2_btree_iter_flags(trans, btree_id, flags));
+
+       iter->min_depth = depth;
+
        BUG_ON(iter->path->locks_want    < min(locks_want, BTREE_MAX_DEPTH));
        BUG_ON(iter->path->level        != depth);
        BUG_ON(iter->min_depth          != depth);

diff --git a/fs/bcachefs/btree_iter.h b/fs/bcachefs/btree_iter.h
index 1c60122c5ea5c1e8a8bca21228db6b1d72d0d3d2..3f46c60b748baec1c47846c84ab482ac2c1a1a5b 100644 (file)
--- a/fs/bcachefs/btree_iter.h
+++ b/fs/bcachefs/btree_iter.h
@@ -315,8 +315,80 @@ static inline void bch2_btree_iter_set_snapshot(struct btree_iter *iter, u32 sna
 }
 
 void bch2_trans_iter_exit(struct btree_trans *, struct btree_iter *);
-void bch2_trans_iter_init(struct btree_trans *, struct btree_iter *,
-                         unsigned, struct bpos, unsigned);
+
+static inline unsigned __bch2_btree_iter_flags(struct btree_trans *trans,
+                                              unsigned btree_id,
+                                              unsigned flags)
+{
+       if (flags & BTREE_ITER_ALL_LEVELS)
+               flags |= BTREE_ITER_ALL_SNAPSHOTS|__BTREE_ITER_ALL_SNAPSHOTS;
+
+       if (!(flags & (BTREE_ITER_ALL_SNAPSHOTS|BTREE_ITER_NOT_EXTENTS)) &&
+           btree_node_type_is_extents(btree_id))
+               flags |= BTREE_ITER_IS_EXTENTS;
+
+       if (!(flags & __BTREE_ITER_ALL_SNAPSHOTS) &&
+           !btree_type_has_snapshots(btree_id))
+               flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
+
+       if (!(flags & BTREE_ITER_ALL_SNAPSHOTS) &&
+           btree_type_has_snapshots(btree_id))
+               flags |= BTREE_ITER_FILTER_SNAPSHOTS;
+
+       if (trans->journal_replay_not_finished)
+               flags |= BTREE_ITER_WITH_JOURNAL;
+
+       return flags;
+}
+
+static inline unsigned bch2_btree_iter_flags(struct btree_trans *trans,
+                                            unsigned btree_id,
+                                            unsigned flags)
+{
+       if (!btree_id_cached(trans->c, btree_id)) {
+               flags &= ~BTREE_ITER_CACHED;
+               flags &= ~BTREE_ITER_WITH_KEY_CACHE;
+       } else if (!(flags & BTREE_ITER_CACHED))
+               flags |= BTREE_ITER_WITH_KEY_CACHE;
+
+       return __bch2_btree_iter_flags(trans, btree_id, flags);
+}
+
+static inline void bch2_trans_iter_init_common(struct btree_trans *trans,
+                                         struct btree_iter *iter,
+                                         unsigned btree_id, struct bpos pos,
+                                         unsigned locks_want,
+                                         unsigned depth,
+                                         unsigned flags)
+{
+       memset(iter, 0, sizeof(*iter));
+       iter->trans     = trans;
+       iter->btree_id  = btree_id;
+       iter->flags     = flags;
+       iter->snapshot  = pos.snapshot;
+       iter->pos       = pos;
+       iter->k.p       = pos;
+
+       iter->path = bch2_path_get(trans, btree_id, iter->pos,
+                                  locks_want, depth, flags);
+}
+
+void bch2_trans_iter_init_outlined(struct btree_trans *, struct btree_iter *,
+                         enum btree_id, struct bpos, unsigned);
+
+static inline void bch2_trans_iter_init(struct btree_trans *trans,
+                         struct btree_iter *iter,
+                         unsigned btree_id, struct bpos pos,
+                         unsigned flags)
+{
+       if (__builtin_constant_p(btree_id) &&
+           __builtin_constant_p(flags))
+               bch2_trans_iter_init_common(trans, iter, btree_id, pos, 0, 0,
+                               bch2_btree_iter_flags(trans, btree_id, flags));
+       else
+               bch2_trans_iter_init_outlined(trans, iter, btree_id, pos, flags);
+}
+
 void bch2_trans_node_iter_init(struct btree_trans *, struct btree_iter *,
                               enum btree_id, struct bpos,
                               unsigned, unsigned, unsigned);

diff --git a/fs/bcachefs/btree_types.h b/fs/bcachefs/btree_types.h
index 72e6a214b89a84a1352f8f06a47dc4ba90bec16b..ae5a692d19248ef6753e1809bd6da4632d1108db 100644 (file)
--- a/fs/bcachefs/btree_types.h
+++ b/fs/bcachefs/btree_types.h
@@ -278,7 +278,6 @@ struct btree_iter {
        unsigned                snapshot;
 
        struct bpos             pos;
-       struct bpos             pos_after_commit;
        /*
         * Current unpacked key - so that bch2_btree_iter_next()/
         * bch2_btree_iter_next_slot() can correctly advance pos.