/*
* __rec_discard_tree --
* Discard the tree rooted a page (that is, any pages merged into it),
* then the page itself.
*/
static void
__rec_discard_tree(WT_SESSION_IMPL *session, WT_PAGE *page, int exclusive)
{
WT_REF *ref;
uint32_t i;
switch (page->type) {
case WT_PAGE_COL_INT:
case WT_PAGE_ROW_INT:
/* For each entry in the page... */
WT_REF_FOREACH(page, ref, i) {
if (ref->state == WT_REF_DISK ||
ref->state == WT_REF_DELETED)
continue;
WT_ASSERT(session,
exclusive || ref->state == WT_REF_LOCKED);
__rec_discard_tree(session, ref->page, exclusive);
}
/* FALLTHROUGH */
default:
__rec_discard_page(session, page, exclusive);
break;
}
}
/*
* __wt_rec_evict --
* Reconciliation plus eviction.
*/
int
__wt_rec_evict(WT_SESSION_IMPL *session, WT_PAGE *page, int exclusive)
{
WT_DECL_RET;
WT_PAGE_MODIFY *mod;
int merge;
WT_VERBOSE_RET(session, evict,
"page %p (%s)", page, __wt_page_type_string(page->type));
WT_ASSERT(session, session->excl_next == 0);
/*
* If we get a split-merge page during normal eviction, try to collapse
* it. During close, it will be merged into its parent.
*/
mod = page->modify;
merge = __wt_btree_mergeable(page);
if (merge && exclusive)
return (EBUSY);
WT_ASSERT(session, merge || mod == NULL ||
!F_ISSET(mod, WT_PM_REC_SPLIT_MERGE));
/*
* Get exclusive access to the page and review the page and its subtree
* for conditions that would block our eviction of the page. If the
* check fails (for example, we find a child page that can't be merged),
* we're done. We have to make this check for clean pages, too: while
* unlikely eviction would choose an internal page with children, it's
* not disallowed anywhere.
*
* Note that page->ref may be NULL in some cases (e.g., for root pages
* or during salvage). That's OK if exclusive is set: we won't check
* hazard pointers in that case.
*/
WT_ERR(__rec_review(session, page->ref, page, exclusive, merge, 1));
/* Try to merge internal pages. */
if (merge)
WT_ERR(__wt_merge_tree(session, page));
/*
* Update the page's modification reference, reconciliation might have
* changed it.
*/
mod = page->modify;
/* Count evictions of internal pages during normal operation. */
if (!exclusive && !merge &&
(page->type == WT_PAGE_COL_INT || page->type == WT_PAGE_ROW_INT)) {
WT_CSTAT_INCR(session, cache_eviction_internal);
WT_DSTAT_INCR(session, cache_eviction_internal);
}
/*
* Update the parent and discard the page.
*/
if (mod == NULL || !F_ISSET(mod, WT_PM_REC_MASK)) {
WT_ASSERT(session,
exclusive || page->ref->state == WT_REF_LOCKED);
if (WT_PAGE_IS_ROOT(page))
__rec_root_update(session);
else
__rec_page_clean_update(session, page);
/* Discard the page. */
__rec_discard_page(session, page, exclusive);
WT_CSTAT_INCR(session, cache_eviction_clean);
WT_DSTAT_INCR(session, cache_eviction_clean);
} else {
if (WT_PAGE_IS_ROOT(page))
__rec_root_update(session);
else
WT_ERR(__rec_page_dirty_update(session, page));
/* Discard the tree rooted in this page. */
__rec_discard_tree(session, page, exclusive);
WT_CSTAT_INCR(session, cache_eviction_dirty);
WT_DSTAT_INCR(session, cache_eviction_dirty);
}
if (0) {
err: /*
* If unable to evict this page, release exclusive reference(s)
* we've acquired.
*/
__rec_excl_clear(session);
WT_CSTAT_INCR(session, cache_eviction_fail);
WT_DSTAT_INCR(session, cache_eviction_fail);
}
session->excl_next = 0;
return (ret);
}
/*
* __wt_rec_evict --
* Reconciliation plus eviction.
*/
int
__wt_rec_evict(WT_SESSION_IMPL *session, WT_PAGE *page, uint32_t flags)
{
WT_CONNECTION_IMPL *conn;
WT_DECL_RET;
int single;
conn = S2C(session);
WT_VERBOSE_RET(session, evict,
"page %p (%s)", page, __wt_page_type_string(page->type));
WT_ASSERT(session, session->excl_next == 0);
single = LF_ISSET(WT_REC_SINGLE) ? 1 : 0;
/*
* Get exclusive access to the page and review the page and its subtree
* for conditions that would block our eviction of the page. If the
* check fails (for example, we find a child page that can't be merged),
* we're done. We have to make this check for clean pages, too: while
* unlikely eviction would choose an internal page with children, it's
* not disallowed anywhere.
*
* Note that page->ref may be NULL in some cases (e.g., for root pages
* or during salvage). That's OK if WT_REC_SINGLE is set: we won't
* check hazard references in that case.
*/
WT_ERR(__rec_review(session, page->ref, page, flags, 1));
/* Count evictions of internal pages during normal operation. */
if (!single &&
(page->type == WT_PAGE_COL_INT || page->type == WT_PAGE_ROW_INT))
WT_STAT_INCR(conn->stats, cache_evict_internal);
/* Update the parent and discard the page. */
if (page->modify == NULL || !F_ISSET(page->modify, WT_PM_REC_MASK)) {
WT_STAT_INCR(conn->stats, cache_evict_unmodified);
WT_ASSERT(session, single || page->ref->state == WT_REF_LOCKED);
if (WT_PAGE_IS_ROOT(page))
__rec_root_update(session);
else
__rec_page_clean_update(session, page);
/* Discard the page. */
__rec_discard_page(session, page, single);
} else {
WT_STAT_INCR(conn->stats, cache_evict_modified);
if (WT_PAGE_IS_ROOT(page))
__rec_root_update(session);
else
WT_ERR(__rec_page_dirty_update(session, page));
/* Discard the tree rooted in this page. */
__rec_discard_tree(session, page, single);
}
if (0) {
err: /*
* If unable to evict this page, release exclusive reference(s)
* we've acquired.
*/
__rec_excl_clear(session);
}
session->excl_next = 0;
return (ret);
}