[PATCH 2/6] vinyl: cache iterator: fold eq check in seek method
Vladimir Davydov
vdavydov.dev at gmail.com
Tue Mar 26 18:50:30 MSK 2019
We substitute iterator_type and key before each call to 'seek'
method and check eq constraint after it. Let's fold it to reduce
code duplication.
---
src/box/vy_cache.c | 82 ++++++++++++++++++++++++------------------------------
1 file changed, 37 insertions(+), 45 deletions(-)
diff --git a/src/box/vy_cache.c b/src/box/vy_cache.c
index 8354b1c2..b27e04a5 100644
--- a/src/box/vy_cache.c
+++ b/src/box/vy_cache.c
@@ -635,28 +635,34 @@ vy_cache_iterator_skip_to_read_view(struct vy_cache_iterator *itr, bool *stop)
/**
* Position the iterator to the first cache entry satisfying
- * the search criteria for a given key and direction.
+ * the iterator search criteria and following the given key
+ * (pass NULL to start iteration).
*/
static void
vy_cache_iterator_seek(struct vy_cache_iterator *itr,
- enum iterator_type iterator_type,
- const struct tuple *key,
- struct vy_cache_entry **entry)
+ const struct tuple *last_key,
+ struct vy_cache_entry **ret)
{
struct vy_cache_tree *tree = &itr->cache->cache_tree;
- *entry = NULL;
+ *ret = NULL;
itr->cache->stat.lookup++;
+ const struct tuple *key = itr->key;
+ enum iterator_type iterator_type = itr->iterator_type;
+ if (last_key != NULL) {
+ key = last_key;
+ iterator_type = iterator_direction(itr->iterator_type) > 0 ?
+ ITER_GT : ITER_LT;
+ }
+
+ bool exact;
if (!vy_stmt_is_empty_key(key)) {
- bool exact;
itr->curr_pos = iterator_type == ITER_EQ ||
iterator_type == ITER_GE ||
iterator_type == ITER_LT ?
vy_cache_tree_lower_bound(tree, key, &exact) :
vy_cache_tree_upper_bound(tree, key, &exact);
- if (iterator_type == ITER_EQ && !exact)
- return;
} else if (iterator_type == ITER_LE) {
itr->curr_pos = vy_cache_tree_invalid_iterator();
} else {
@@ -669,7 +675,16 @@ vy_cache_iterator_seek(struct vy_cache_iterator *itr,
if (vy_cache_tree_iterator_is_invalid(&itr->curr_pos))
return;
- *entry = *vy_cache_tree_iterator_get_elem(tree, &itr->curr_pos);
+ struct vy_cache_entry *entry;
+ entry = *vy_cache_tree_iterator_get_elem(tree, &itr->curr_pos);
+
+ if (itr->iterator_type == ITER_EQ &&
+ ((last_key == NULL && !exact) ||
+ (last_key != NULL && vy_stmt_compare(itr->key, entry->stmt,
+ itr->cache->cmp_def) != 0)))
+ return;
+
+ *ret = entry;
}
NODISCARD int
@@ -684,8 +699,7 @@ vy_cache_iterator_next(struct vy_cache_iterator *itr,
itr->search_started = true;
itr->version = itr->cache->version;
struct vy_cache_entry *entry;
- vy_cache_iterator_seek(itr, itr->iterator_type,
- itr->key, &entry);
+ vy_cache_iterator_seek(itr, NULL, &entry);
if (entry == NULL)
return 0;
itr->curr_stmt = entry->stmt;
@@ -735,22 +749,8 @@ vy_cache_iterator_skip(struct vy_cache_iterator *itr,
tuple_unref(itr->curr_stmt);
itr->curr_stmt = NULL;
- const struct tuple *key = itr->key;
- enum iterator_type iterator_type = itr->iterator_type;
- if (last_stmt != NULL) {
- key = last_stmt;
- iterator_type = iterator_direction(iterator_type) > 0 ?
- ITER_GT : ITER_LT;
- }
-
struct vy_cache_entry *entry;
- vy_cache_iterator_seek(itr, iterator_type, key, &entry);
-
- if (itr->iterator_type == ITER_EQ && last_stmt != NULL &&
- entry != NULL && vy_stmt_compare(itr->key, entry->stmt,
- itr->cache->cmp_def) != 0)
- entry = NULL;
-
+ vy_cache_iterator_seek(itr, last_stmt, &entry);
if (entry != NULL) {
*stop = vy_cache_iterator_is_stop(itr, entry);
itr->curr_stmt = entry->stmt;
@@ -771,9 +771,6 @@ vy_cache_iterator_restore(struct vy_cache_iterator *itr,
const struct tuple *last_stmt,
struct vy_history *history, bool *stop)
{
- struct key_def *def = itr->cache->cmp_def;
- int dir = iterator_direction(itr->iterator_type);
-
if (!itr->search_started || itr->version == itr->cache->version)
return 0;
@@ -782,13 +779,6 @@ vy_cache_iterator_restore(struct vy_cache_iterator *itr,
if (prev_stmt != NULL)
tuple_unref(prev_stmt);
- const struct tuple *key = itr->key;
- enum iterator_type iterator_type = itr->iterator_type;
- if (last_stmt != NULL) {
- key = last_stmt;
- iterator_type = dir > 0 ? ITER_GT : ITER_LT;
- }
-
if ((prev_stmt == NULL && itr->iterator_type == ITER_EQ) ||
(prev_stmt != NULL &&
prev_stmt != vy_cache_iterator_curr_stmt(itr))) {
@@ -798,13 +788,8 @@ vy_cache_iterator_restore(struct vy_cache_iterator *itr,
* search.
*/
struct vy_cache_entry *entry;
- vy_cache_iterator_seek(itr, iterator_type, key, &entry);
-
+ vy_cache_iterator_seek(itr, last_stmt, &entry);
itr->curr_stmt = NULL;
- if (entry != NULL && itr->iterator_type == ITER_EQ &&
- vy_stmt_compare(itr->key, entry->stmt, def) != 0)
- entry = NULL;
-
if (entry != NULL) {
*stop = vy_cache_iterator_is_stop(itr, entry);
itr->curr_stmt = entry->stmt;
@@ -817,11 +802,18 @@ vy_cache_iterator_restore(struct vy_cache_iterator *itr,
* and the current statement. Reposition to the
* statement closiest to last_stmt.
*/
+ bool key_belongs = false;
+ const struct tuple *key = last_stmt;
+ if (key == NULL) {
+ key = itr->key;
+ key_belongs = (itr->iterator_type == ITER_EQ ||
+ itr->iterator_type == ITER_GE ||
+ itr->iterator_type == ITER_LE);
+ }
+ int dir = iterator_direction(itr->iterator_type);
+ struct key_def *def = itr->cache->cmp_def;
struct vy_cache_tree *tree = &itr->cache->cache_tree;
struct vy_cache_tree_iterator pos = itr->curr_pos;
- bool key_belongs = (iterator_type == ITER_EQ ||
- iterator_type == ITER_GE ||
- iterator_type == ITER_LE);
if (prev_stmt == NULL)
pos = vy_cache_tree_invalid_iterator();
while (true) {
--
2.11.0
More information about the Tarantool-patches
mailing list