diff options
| -rw-r--r-- | include/my_sys.h | 6 | ||||
| -rw-r--r-- | include/my_tree.h | 3 | ||||
| -rw-r--r-- | mysql-test/r/count_distinct2.result | 4 | ||||
| -rw-r--r-- | mysql-test/t/count_distinct2.test | 3 | ||||
| -rw-r--r-- | mysys/my_alloc.c | 41 | ||||
| -rw-r--r-- | mysys/tree.c | 18 | ||||
| -rw-r--r-- | sql/item_sum.cc | 2 |
7 files changed, 71 insertions, 6 deletions
diff --git a/include/my_sys.h b/include/my_sys.h index 44faddad405..b5d59d2e801 100644 --- a/include/my_sys.h +++ b/include/my_sys.h @@ -108,7 +108,11 @@ extern int NEAR my_errno; /* Last error in mysys */ /* root_alloc flags */ #define MY_KEEP_PREALLOC 1 - +#define MY_MARK_BLOCKS_FREE 2 /* do not my_free() blocks, + just move used into free list + and mark all blocks as fully free + */ + /* defines when allocating data */ #ifdef SAFEMALLOC diff --git a/include/my_tree.h b/include/my_tree.h index d4d28644a39..be95e3ff4d2 100644 --- a/include/my_tree.h +++ b/include/my_tree.h @@ -62,6 +62,9 @@ void init_tree(TREE *tree,uint default_alloc_size, int element_size, qsort_cmp2 compare, my_bool with_delete, void (*free_element)(void*)); void delete_tree(TREE*); +void reset_tree(TREE*); + /* similar to delete tree, except we do not my_free() blocks in mem_root + */ #define is_tree_inited(tree) ((tree)->root != 0) /* Functions on leafs */ diff --git a/mysql-test/r/count_distinct2.result b/mysql-test/r/count_distinct2.result index b2bcf11a37c..b8330835332 100644 --- a/mysql-test/r/count_distinct2.result +++ b/mysql-test/r/count_distinct2.result @@ -70,3 +70,7 @@ count(distinct s,t) 5 count(distinct n1) count(distinct n2) 2 3 +count(distinct n2) n1 +1 NULL +1 1 +3 2 diff --git a/mysql-test/t/count_distinct2.test b/mysql-test/t/count_distinct2.test index cfdce77622c..5ddd96198fe 100644 --- a/mysql-test/t/count_distinct2.test +++ b/mysql-test/t/count_distinct2.test @@ -40,3 +40,6 @@ select distinct s,t from t1; select count(distinct s,t) from t1; select count(distinct n1), count(distinct n2) from t1; + +select count(distinct n2), n1 from t1 group by n1; +drop table t1; diff --git a/mysys/my_alloc.c b/mysys/my_alloc.c index db482454e69..b82ff965dfb 100644 --- a/mysys/my_alloc.c +++ b/mysys/my_alloc.c @@ -100,7 +100,41 @@ gptr alloc_root(MEM_ROOT *mem_root,unsigned int Size) #endif } - /* deallocate everything used by alloc_root */ +static inline void mark_blocks_free(MEM_ROOT* root) +{ + reg1 USED_MEM *next,*last = 0; + + /* iterate through (partially) free blocks, mark them fully free */ + for(next = root->free; next; next = next->next ) + { + last = next; + next->left = next->size - ALIGN_SIZE(sizeof(USED_MEM)); + } + /* if free block list was not empty, point the next of the + last free block to the beginning of the used list */ + next = root->used; /* a little optimization to avoid dereferencing root + twice - we will shortly start iterating through used + list */ + if(last) + last->next = next; + else /* if free list is empty, just point it to the current used*/ + root->free = next; + + /* now go through the current used list, and mark each block + as fully free. Note that because of our optimization, we do not + need to initialize next here - see above + */ + for(;next; next = next->next) + next->left = next->size - ALIGN_SIZE(sizeof(USED_MEM)); + + /* Now everything is set - we just need to indicate that nothing is used + anymore + */ + root->used = 0; +} + + /* deallocate everything used by alloc_root or just move + used blocks to free list if called with MY_USED_TO_FREE */ void free_root(MEM_ROOT *root, myf MyFlags) { @@ -109,6 +143,11 @@ void free_root(MEM_ROOT *root, myf MyFlags) if (!root) DBUG_VOID_RETURN; /* purecov: inspected */ + if(MyFlags & MY_MARK_BLOCKS_FREE) + { + mark_blocks_free(root); + DBUG_VOID_RETURN; + } if (!(MyFlags & MY_KEEP_PREALLOC)) root->pre_alloc=0; diff --git a/mysys/tree.c b/mysys/tree.c index e46ff00adad..af64be55d2f 100644 --- a/mysys/tree.c +++ b/mysys/tree.c @@ -103,9 +103,9 @@ void init_tree(TREE *tree, uint default_alloc_size, int size, DBUG_VOID_RETURN; } -void delete_tree(TREE *tree) +static void free_tree(TREE *tree, myf free_flags) { - DBUG_ENTER("delete_tree"); + DBUG_ENTER("free_tree"); DBUG_PRINT("enter",("tree: %lx",tree)); if (tree->root) /* If initialized */ @@ -116,7 +116,7 @@ void delete_tree(TREE *tree) { if (tree->free) delete_tree_element(tree,tree->root); - free_root(&tree->mem_root,MYF(0)); + free_root(&tree->mem_root, free_flags); } } tree->root= &tree->null_element; @@ -125,6 +125,18 @@ void delete_tree(TREE *tree) DBUG_VOID_RETURN; } +void delete_tree(TREE* tree) +{ + free_tree(tree, MYF(0)); /* my_free() mem_root if applicable */ +} + +void reset_tree(TREE* tree) +{ + free_tree(tree, MYF(MY_MARK_BLOCKS_FREE)); + /* do not my_free() mem_root if applicable, just mark blocks as free */ +} + + static void delete_tree_element(TREE *tree, TREE_ELEMENT *element) { if (element != &tree->null_element) diff --git a/sql/item_sum.cc b/sql/item_sum.cc index c0fba1dd80d..ad1918e01e3 100644 --- a/sql/item_sum.cc +++ b/sql/item_sum.cc @@ -924,7 +924,7 @@ bool Item_sum_count_distinct::setup(THD *thd) void Item_sum_count_distinct::reset() { if(use_tree) - delete_tree(&tree); + reset_tree(&tree); else { table->file->extra(HA_EXTRA_NO_CACHE); |