diff options
Diffstat (limited to 'src/third_party/wiredtiger/src/btree/bt_ret.c')
| -rw-r--r-- | src/third_party/wiredtiger/src/btree/bt_ret.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/src/third_party/wiredtiger/src/btree/bt_ret.c b/src/third_party/wiredtiger/src/btree/bt_ret.c index 120daed3935..49a2481062e 100644 --- a/src/third_party/wiredtiger/src/btree/bt_ret.c +++ b/src/third_party/wiredtiger/src/btree/bt_ret.c @@ -129,9 +129,17 @@ __value_return(WT_SESSION_IMPL *session, WT_CURSOR_BTREE *cbt) } /* + * When threads race modifying a record, we can end up with more than the usual + * maximum number of modifications in an update list. We'd prefer not to + * allocate memory in a return path, so add a few additional slots to the array + * we use to build up a list of modify records to apply. + */ +#define WT_MODIFY_ARRAY_SIZE (WT_MAX_MODIFY_UPDATE + 10) + +/* * __value_return_upd -- * Change the cursor to reference an internal update structure return - * value. + * value. */ static inline int __value_return_upd( @@ -139,7 +147,7 @@ __value_return_upd( { WT_CURSOR *cursor; WT_DECL_RET; - WT_UPDATE **listp, *list[WT_MAX_MODIFY_UPDATE]; + WT_UPDATE **listp, *list[WT_MODIFY_ARRAY_SIZE]; u_int i; size_t allocated_bytes; @@ -178,12 +186,12 @@ __value_return_upd( * avoid memory allocation in normal cases, but we have * to handle the edge cases too. */ - if (i >= WT_MAX_MODIFY_UPDATE) { - if (i == WT_MAX_MODIFY_UPDATE) + if (i >= WT_MODIFY_ARRAY_SIZE) { + if (i == WT_MODIFY_ARRAY_SIZE) listp = NULL; WT_ERR(__wt_realloc_def( session, &allocated_bytes, i + 1, &listp)); - if (i == WT_MAX_MODIFY_UPDATE) + if (i == WT_MODIFY_ARRAY_SIZE) memcpy(listp, list, sizeof(list)); } listp[i++] = upd; |