/*
* __wt_session_fotxn_discard --
* Discard any memory from the session's free-on-transaction generation
* list that we can.
*/
void
__wt_session_fotxn_discard(WT_SESSION_IMPL *session_safe,
WT_SESSION_IMPL *session, int connection_close)
{
WT_FOTXN *fotxn;
size_t i;
/*
* This function is called during WT_CONNECTION.close to discard any
* memory that remains. For that reason, we take two WT_SESSION_IMPL
* arguments: session_safe is still linked to the WT_CONNECTION and
* can be safely used for calls to other WiredTiger functions, while
* session is the WT_SESSION_IMPL we're cleaning up.
*/
for (i = 0, fotxn = session->fotxn;
session->fotxn_cnt > 0 &&
i < session->fotxn_size / sizeof(session->fotxn[0]); ++i, ++fotxn)
if (fotxn->p != NULL && (connection_close ||
__wt_txn_visible_all(session_safe, fotxn->txnid))) {
--session->fotxn_cnt;
/*
* It's a bad thing if another thread is in this memory
* after we free it, make sure nothing good happens to
* that thread.
*/
__wt_overwrite_and_free_len(
session_safe, fotxn->p, fotxn->len);
}
if (connection_close)
__wt_free(session_safe, session->fotxn);
}
/*
* __wt_split_stash_discard --
* Discard any memory from a session's split stash that we can.
*/
void
__wt_split_stash_discard(WT_SESSION_IMPL *session)
{
WT_CONNECTION_IMPL *conn;
WT_SPLIT_STASH *stash;
uint64_t oldest;
size_t i;
conn = S2C(session);
/* Get the oldest split generation. */
oldest = __split_oldest_gen(session);
for (i = 0, stash = session->split_stash;
i < session->split_stash_cnt;
++i, ++stash) {
if (stash->p == NULL)
continue;
else if (stash->split_gen >= oldest)
break;
/*
* It's a bad thing if another thread is in this memory after
* we free it, make sure nothing good happens to that thread.
*/
(void)__wt_atomic_sub64(&conn->split_stashed_bytes, stash->len);
(void)__wt_atomic_sub64(&conn->split_stashed_objects, 1);
__wt_overwrite_and_free_len(session, stash->p, stash->len);
}
/*
* If there are enough free slots at the beginning of the list, shuffle
* everything down.
*/
if (i > 100 || i == session->split_stash_cnt)
if ((session->split_stash_cnt -= i) > 0)
memmove(session->split_stash, stash,
session->split_stash_cnt * sizeof(*stash));
}
/*
* __wt_page_out --
* Discard an in-memory page, freeing all memory associated with it.
*/
void
__wt_page_out(WT_SESSION_IMPL *session, WT_PAGE **pagep)
{
WT_PAGE *page;
WT_PAGE_HEADER *dsk;
WT_PAGE_MODIFY *mod;
/*
* Kill our caller's reference, do our best to catch races.
*/
page = *pagep;
*pagep = NULL;
if (F_ISSET(session->dhandle, WT_DHANDLE_DEAD))
__wt_page_modify_clear(session, page);
/*
* We should never discard:
* - a dirty page,
* - a page queued for eviction, or
* - a locked page.
*/
WT_ASSERT(session, !__wt_page_is_modified(page));
WT_ASSERT(session, !F_ISSET_ATOMIC(page, WT_PAGE_EVICT_LRU));
WT_ASSERT(session, !__wt_fair_islocked(session, &page->page_lock));
#ifdef HAVE_DIAGNOSTIC
{
WT_HAZARD *hp;
int i;
/*
* Make sure no other thread has a hazard pointer on the page we are
* about to discard. This is complicated by the fact that readers
* publish their hazard pointer before re-checking the page state, so
* our check can race with readers without indicating a real problem.
* Wait for up to a second for hazard pointers to be cleared.
*/
for (hp = NULL, i = 0; i < 100; i++) {
if ((hp = __wt_page_hazard_check(session, page)) == NULL)
break;
__wt_sleep(0, 10000);
}
if (hp != NULL)
__wt_errx(session,
"discarded page has hazard pointer: (%p: %s, line %d)",
hp->page, hp->file, hp->line);
WT_ASSERT(session, hp == NULL);
}
#endif
/*
* If a root page split, there may be one or more pages linked from the
* page; walk the list, discarding pages.
*/
switch (page->type) {
case WT_PAGE_COL_INT:
case WT_PAGE_ROW_INT:
mod = page->modify;
if (mod != NULL && mod->mod_root_split != NULL)
__wt_page_out(session, &mod->mod_root_split);
break;
}
/* Update the cache's information. */
__wt_cache_page_evict(session, page);
/*
* If discarding the page as part of process exit, the application may
* configure to leak the memory rather than do the work.
*/
if (F_ISSET(S2C(session), WT_CONN_LEAK_MEMORY))
return;
/* Free the page modification information. */
if (page->modify != NULL)
__free_page_modify(session, page);
switch (page->type) {
case WT_PAGE_COL_FIX:
break;
case WT_PAGE_COL_INT:
case WT_PAGE_ROW_INT:
__free_page_int(session, page);
break;
case WT_PAGE_COL_VAR:
__free_page_col_var(session, page);
break;
case WT_PAGE_ROW_LEAF:
__free_page_row_leaf(session, page);
break;
}
/* Discard any disk image. */
dsk = (WT_PAGE_HEADER *)page->dsk;
if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_ALLOC))
__wt_overwrite_and_free_len(session, dsk, dsk->mem_size);
if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_MAPPED))
(void)__wt_mmap_discard(session, dsk, dsk->mem_size);
__wt_overwrite_and_free(session, page);
}
/*
* __wt_page_out --
* Discard an in-memory page, freeing all memory associated with it.
*/
void
__wt_page_out(WT_SESSION_IMPL *session, WT_PAGE **pagep)
{
WT_PAGE *page;
WT_PAGE_HEADER *dsk;
WT_PAGE_MODIFY *mod;
/*
* Kill our caller's reference, do our best to catch races.
*/
page = *pagep;
*pagep = NULL;
if (F_ISSET(session->dhandle, WT_DHANDLE_DEAD))
__wt_page_modify_clear(session, page);
/*
* We should never discard:
* - a dirty page,
* - a page queued for eviction, or
* - a locked page.
*/
WT_ASSERT(session, !__wt_page_is_modified(page));
WT_ASSERT(session, !F_ISSET_ATOMIC(page, WT_PAGE_EVICT_LRU));
WT_ASSERT(session, !__wt_rwlock_islocked(session, &page->page_lock));
/*
* If a root page split, there may be one or more pages linked from the
* page; walk the list, discarding pages.
*/
switch (page->type) {
case WT_PAGE_COL_INT:
case WT_PAGE_ROW_INT:
mod = page->modify;
if (mod != NULL && mod->mod_root_split != NULL)
__wt_page_out(session, &mod->mod_root_split);
break;
}
/* Update the cache's information. */
__wt_cache_page_evict(session, page);
dsk = (WT_PAGE_HEADER *)page->dsk;
if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_ALLOC))
__wt_cache_page_image_decr(session, dsk->mem_size);
/* Discard any mapped image. */
if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_MAPPED))
(void)S2BT(session)->bm->map_discard(
S2BT(session)->bm, session, dsk, (size_t)dsk->mem_size);
/*
* If discarding the page as part of process exit, the application may
* configure to leak the memory rather than do the work.
*/
if (F_ISSET(S2C(session), WT_CONN_LEAK_MEMORY))
return;
/* Free the page modification information. */
if (page->modify != NULL)
__free_page_modify(session, page);
switch (page->type) {
case WT_PAGE_COL_FIX:
break;
case WT_PAGE_COL_INT:
case WT_PAGE_ROW_INT:
__free_page_int(session, page);
break;
case WT_PAGE_COL_VAR:
__free_page_col_var(session, page);
break;
case WT_PAGE_ROW_LEAF:
__free_page_row_leaf(session, page);
break;
}
/* Discard any allocated disk image. */
if (F_ISSET_ATOMIC(page, WT_PAGE_DISK_ALLOC))
__wt_overwrite_and_free_len(session, dsk, dsk->mem_size);
__wt_overwrite_and_free(session, page);
}
