@@ -1546,17 +1546,23 @@ retry:
return pages;
}
+#define PAGE_ALL_CLEAN 0
+#define PAGE_TRY_AGAIN 1
+#define PAGE_DIRTY_FOUND 2
/**
* find_dirty_block: find the next dirty page and update any state
* associated with the search process.
*
- * Returns true if a page is found
+ * Returns:
+ * PAGE_ALL_CLEAN: no dirty page found, give up
+ * PAGE_TRY_AGAIN: no dirty page found, retry for next block
+ * PAGE_DIRTY_FOUND: dirty page found
*
* @rs: current RAM state
* @pss: data about the state of the current dirty page scan
* @again: set to false if the search has scanned the whole of RAM
*/
-static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, bool *again)
+static int find_dirty_block(RAMState *rs, PageSearchStatus *pss)
{
/* Update pss->page for the next dirty bit in ramblock */
pss_find_next_dirty(pss);
@@ -1567,8 +1573,7 @@ static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, bool *again)
* We've been once around the RAM and haven't found anything.
* Give up.
*/
- *again = false;
- return false;
+ return PAGE_ALL_CLEAN;
}
if (!offset_in_ramblock(pss->block,
((ram_addr_t)pss->page) << TARGET_PAGE_BITS)) {
@@ -1597,13 +1602,10 @@ static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, bool *again)
}
}
/* Didn't find anything this time, but try again on the new block */
- *again = true;
- return false;
+ return PAGE_TRY_AGAIN;
} else {
- /* Can go around again, but... */
- *again = true;
- /* We've found something so probably don't need to */
- return true;
+ /* We've found something */
+ return PAGE_DIRTY_FOUND;
}
}
@@ -2562,19 +2564,23 @@ static int ram_find_and_save_block(RAMState *rs)
pss_init(pss, rs->last_seen_block, rs->last_page);
- do {
+ while (true) {
if (!get_queued_page(rs, pss)) {
/* priority queue empty, so just search for something dirty */
- bool again = true;
- if (!find_dirty_block(rs, pss, &again)) {
- if (!again) {
+ int res = find_dirty_block(rs, pss);
+ if (res != PAGE_DIRTY_FOUND) {
+ if (res == PAGE_ALL_CLEAN) {
break;
+ } else if (res == PAGE_TRY_AGAIN) {
+ continue;
}
}
- pages = ram_save_host_page(rs, pss);
}
- } while (!pages);
-
+ pages = ram_save_host_page(rs, pss);
+ if (pages) {
+ break;
+ }
+ }
rs->last_seen_block = pss->block;
rs->last_page = pss->page;
We used to return two bools, just return a single int with the following meaning: old return / again / new return false false PAGE_ALL_CLEAN false true PAGE_TRY_AGAIN true true PAGE_DIRTY_FOUND /* We don't care about again at all */ Signed-off-by: Juan Quintela <quintela@redhat.com> --- migration/ram.c | 40 +++++++++++++++++++++++----------------- 1 file changed, 23 insertions(+), 17 deletions(-)