diff options
| -rw-r--r-- | src/btree/bt_cursor.c | 38 |
1 files changed, 28 insertions, 10 deletions
diff --git a/src/btree/bt_cursor.c b/src/btree/bt_cursor.c index ee800ca80ee..e5d5e64194f 100644 --- a/src/btree/bt_cursor.c +++ b/src/btree/bt_cursor.c @@ -52,15 +52,18 @@ __cursor_state_restore(WT_CURSOR *cursor, WT_CURFILE_STATE *state) /* * __cursor_page_pinned -- - * Return if we have a page pinned and it's not been flagged for forced - * eviction (the forced eviction test is so we periodically release pages - * grown too large). + * Return if we have a page pinned. */ static inline bool -__cursor_page_pinned(WT_CURSOR_BTREE *cbt) +__cursor_page_pinned(WT_CURSOR_BTREE *cbt, bool eviction_ok) { + /* + * Optionally fail the page-pinned test when the page is flagged for + * forced eviction (so we periodically release pages grown too large). + * The test is optional as not all callers can release pinned pages. + */ return (F_ISSET(cbt, WT_CBT_ACTIVE) && - cbt->ref->page->read_gen != WT_READGEN_OLDEST); + (!eviction_ok || cbt->ref->page->read_gen != WT_READGEN_OLDEST)); } /* @@ -465,7 +468,7 @@ __wt_btcur_search(WT_CURSOR_BTREE *cbt) * from the root. */ valid = false; - if (__cursor_page_pinned(cbt)) { + if (__cursor_page_pinned(cbt, true)) { __wt_txn_cursor_op(session); WT_ERR(btree->type == BTREE_ROW ? @@ -562,7 +565,7 @@ __wt_btcur_search_near(WT_CURSOR_BTREE *cbt, int *exactp) * existing record. */ valid = false; - if (btree->type == BTREE_ROW && __cursor_page_pinned(cbt)) { + if (btree->type == BTREE_ROW && __cursor_page_pinned(cbt, true)) { __wt_txn_cursor_op(session); WT_ERR(__cursor_row_search(session, cbt, cbt->ref, true)); @@ -693,7 +696,7 @@ __wt_btcur_insert(WT_CURSOR_BTREE *cbt) * configured for append aren't included, regardless of whether or not * they meet all other criteria. */ - if (__cursor_page_pinned(cbt) && + if (__cursor_page_pinned(cbt, true) && F_ISSET_ALL(cursor, WT_CURSTD_KEY_INT | WT_CURSTD_OVERWRITE) && !append_key) { WT_ERR(__wt_txn_autocommit_check(session)); @@ -912,8 +915,22 @@ __wt_btcur_remove(WT_CURSOR_BTREE *cbt) * removed, and the record must exist with a positioned cursor. The * cursor won't be positioned on a page with an external key set, but * be sure. + * + * There's trickiness in the page-pinned check. By definition a remove + * operation leaves a cursor positioned if it's initially positioned. + * However, if every item on the page is deleted and we unpin the page, + * eviction might delete the page and our search will re-instantiate an + * empty page for us. Cursor remove returns not-found whether or not + * that eviction/deletion happens and it's OK unless cursor-overwrite + * is configured (which means we return success even if there's no item + * to delete). In that case, we'll fail when we try to point the cursor + * at the key on the page to satisfy the positioned requirement. It's + * arguably safe to simply leave the key initialized in the cursor (as + * that's all a positioned cursor implies), but it's probably safer to + * avoid page eviction entirely in the positioned case. */ - if (__cursor_page_pinned(cbt) && F_ISSET(cursor, WT_CURSTD_KEY_INT)) { + if (__cursor_page_pinned(cbt, !positioned) && + F_ISSET(cursor, WT_CURSTD_KEY_INT)) { WT_ERR(__wt_txn_autocommit_check(session)); /* @@ -1055,7 +1072,8 @@ __btcur_update(WT_CURSOR_BTREE *cbt, WT_ITEM *value, u_int modify_type) * cursor won't be positioned on a page with an external key set, but * be sure. */ - if (__cursor_page_pinned(cbt) && F_ISSET(cursor, WT_CURSTD_KEY_INT)) { + if (__cursor_page_pinned(cbt, true) && + F_ISSET(cursor, WT_CURSTD_KEY_INT)) { WT_ERR(__wt_txn_autocommit_check(session)); /* |