{
zone->compact_cached_migrate_pfn[0] = zone->zone_start_pfn;
zone->compact_cached_migrate_pfn[1] = zone->zone_start_pfn;
- zone->compact_cached_free_pfn = zone_end_pfn(zone);
+ zone->compact_cached_free_pfn =
+ round_down(zone_end_pfn(zone) - 1, pageblock_nr_pages);
}
/*
/* Found a free page, break it into order-0 pages */
isolated = split_free_page(page);
+ if (!isolated)
+ break;
+
total_isolated += isolated;
+ cc->nr_freepages += isolated;
for (i = 0; i < isolated; i++) {
list_add(&page->lru, freelist);
page++;
}
-
- /* If a page was split, advance to the end of it */
- if (isolated) {
- cc->nr_freepages += isolated;
- if (!strict &&
- cc->nr_migratepages <= cc->nr_freepages) {
- blockpfn += isolated;
- break;
- }
-
- blockpfn += isolated - 1;
- cursor += isolated - 1;
- continue;
+ if (!strict && cc->nr_migratepages <= cc->nr_freepages) {
+ blockpfn += isolated;
+ break;
}
+ /* Advance to the end of split page */
+ blockpfn += isolated - 1;
+ cursor += isolated - 1;
+ continue;
isolate_fail:
if (strict)
}
+ if (locked)
+ spin_unlock_irqrestore(&cc->zone->lock, flags);
+
/*
* There is a tiny chance that we have read bogus compound_order(),
* so be careful to not go outside of the pageblock.
if (strict && blockpfn < end_pfn)
total_isolated = 0;
- if (locked)
- spin_unlock_irqrestore(&cc->zone->lock, flags);
-
/* Update the pageblock-skip if the whole pageblock was scanned */
if (blockpfn == end_pfn)
update_pageblock_skip(cc, valid_page, total_isolated, false);
isolate_freepages_range(struct compact_control *cc,
unsigned long start_pfn, unsigned long end_pfn)
{
- unsigned long isolated, pfn, block_end_pfn;
+ unsigned long isolated, pfn, block_start_pfn, block_end_pfn;
LIST_HEAD(freelist);
pfn = start_pfn;
+ block_start_pfn = pfn & ~(pageblock_nr_pages - 1);
+ if (block_start_pfn < cc->zone->zone_start_pfn)
+ block_start_pfn = cc->zone->zone_start_pfn;
block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
for (; pfn < end_pfn; pfn += isolated,
+ block_start_pfn = block_end_pfn,
block_end_pfn += pageblock_nr_pages) {
/* Protect pfn from changing by isolate_freepages_block */
unsigned long isolate_start_pfn = pfn;
* scanning range to right one.
*/
if (pfn >= block_end_pfn) {
+ block_start_pfn = pfn & ~(pageblock_nr_pages - 1);
block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
block_end_pfn = min(block_end_pfn, end_pfn);
}
- if (!pageblock_pfn_to_page(pfn, block_end_pfn, cc->zone))
+ if (!pageblock_pfn_to_page(block_start_pfn,
+ block_end_pfn, cc->zone))
break;
isolated = isolate_freepages_block(cc, &isolate_start_pfn,
isolate_migratepages_range(struct compact_control *cc, unsigned long start_pfn,
unsigned long end_pfn)
{
- unsigned long pfn, block_end_pfn;
+ unsigned long pfn, block_start_pfn, block_end_pfn;
/* Scan block by block. First and last block may be incomplete */
pfn = start_pfn;
+ block_start_pfn = pfn & ~(pageblock_nr_pages - 1);
+ if (block_start_pfn < cc->zone->zone_start_pfn)
+ block_start_pfn = cc->zone->zone_start_pfn;
block_end_pfn = ALIGN(pfn + 1, pageblock_nr_pages);
for (; pfn < end_pfn; pfn = block_end_pfn,
+ block_start_pfn = block_end_pfn,
block_end_pfn += pageblock_nr_pages) {
block_end_pfn = min(block_end_pfn, end_pfn);
- if (!pageblock_pfn_to_page(pfn, block_end_pfn, cc->zone))
+ if (!pageblock_pfn_to_page(block_start_pfn,
+ block_end_pfn, cc->zone))
continue;
pfn = isolate_migratepages_block(cc, pfn, block_end_pfn,
ISOLATE_UNEVICTABLE);
- /*
- * In case of fatal failure, release everything that might
- * have been isolated in the previous iteration, and signal
- * the failure back to caller.
- */
- if (!pfn) {
- putback_movable_pages(&cc->migratepages);
- cc->nr_migratepages = 0;
+ if (!pfn)
break;
- }
if (cc->nr_migratepages == COMPACT_CLUSTER_MAX)
break;
block_end_pfn = block_start_pfn,
block_start_pfn -= pageblock_nr_pages,
isolate_start_pfn = block_start_pfn) {
-
/*
* This can iterate a massively long zone without finding any
* suitable migration targets, so periodically check if we need
continue;
/* Found a block suitable for isolating free pages from. */
- isolate_freepages_block(cc, &isolate_start_pfn,
- block_end_pfn, freelist, false);
+ isolate_freepages_block(cc, &isolate_start_pfn, block_end_pfn,
+ freelist, false);
/*
- * If we isolated enough freepages, or aborted due to async
- * compaction being contended, terminate the loop.
- * Remember where the free scanner should restart next time,
- * which is where isolate_freepages_block() left off.
- * But if it scanned the whole pageblock, isolate_start_pfn
- * now points at block_end_pfn, which is the start of the next
- * pageblock.
- * In that case we will however want to restart at the start
- * of the previous pageblock.
+ * If we isolated enough freepages, or aborted due to lock
+ * contention, terminate.
*/
if ((cc->nr_freepages >= cc->nr_migratepages)
|| cc->contended) {
- if (isolate_start_pfn >= block_end_pfn)
+ if (isolate_start_pfn >= block_end_pfn) {
+ /*
+ * Restart at previous pageblock if more
+ * freepages can be isolated next time.
+ */
isolate_start_pfn =
block_start_pfn - pageblock_nr_pages;
+ }
break;
- } else {
+ } else if (isolate_start_pfn < block_end_pfn) {
/*
- * isolate_freepages_block() should not terminate
- * prematurely unless contended, or isolated enough
+ * If isolation failed early, do not continue
+ * needlessly.
*/
- VM_BUG_ON(isolate_start_pfn < block_end_pfn);
+ break;
}
}
static isolate_migrate_t isolate_migratepages(struct zone *zone,
struct compact_control *cc)
{
- unsigned long low_pfn, end_pfn;
+ unsigned long block_start_pfn;
+ unsigned long block_end_pfn;
+ unsigned long low_pfn;
unsigned long isolate_start_pfn;
struct page *page;
const isolate_mode_t isolate_mode =
* initialized by compact_zone()
*/
low_pfn = cc->migrate_pfn;
+ block_start_pfn = cc->migrate_pfn & ~(pageblock_nr_pages - 1);
+ if (block_start_pfn < zone->zone_start_pfn)
+ block_start_pfn = zone->zone_start_pfn;
/* Only scan within a pageblock boundary */
- end_pfn = ALIGN(low_pfn + 1, pageblock_nr_pages);
+ block_end_pfn = ALIGN(low_pfn + 1, pageblock_nr_pages);
/*
* Iterate over whole pageblocks until we find the first suitable.
* Do not cross the free scanner.
*/
- for (; end_pfn <= cc->free_pfn;
- low_pfn = end_pfn, end_pfn += pageblock_nr_pages) {
+ for (; block_end_pfn <= cc->free_pfn;
+ low_pfn = block_end_pfn,
+ block_start_pfn = block_end_pfn,
+ block_end_pfn += pageblock_nr_pages) {
/*
* This can potentially iterate a massively long zone with
&& compact_should_abort(cc))
break;
- page = pageblock_pfn_to_page(low_pfn, end_pfn, zone);
+ page = pageblock_pfn_to_page(block_start_pfn, block_end_pfn,
+ zone);
if (!page)
continue;
/* Perform the isolation */
isolate_start_pfn = low_pfn;
- low_pfn = isolate_migratepages_block(cc, low_pfn, end_pfn,
- isolate_mode);
+ low_pfn = isolate_migratepages_block(cc, low_pfn,
+ block_end_pfn, isolate_mode);
if (!low_pfn || cc->contended) {
acct_isolated(zone, cc);
*/
cc->migrate_pfn = zone->compact_cached_migrate_pfn[sync];
cc->free_pfn = zone->compact_cached_free_pfn;
- if (cc->free_pfn < start_pfn || cc->free_pfn > end_pfn) {
- cc->free_pfn = end_pfn & ~(pageblock_nr_pages-1);
+ if (cc->free_pfn < start_pfn || cc->free_pfn >= end_pfn) {
+ cc->free_pfn = round_down(end_pfn - 1, pageblock_nr_pages);
zone->compact_cached_free_pfn = cc->free_pfn;
}
- if (cc->migrate_pfn < start_pfn || cc->migrate_pfn > end_pfn) {
+ if (cc->migrate_pfn < start_pfn || cc->migrate_pfn >= end_pfn) {
cc->migrate_pfn = start_pfn;
zone->compact_cached_migrate_pfn[0] = cc->migrate_pfn;
zone->compact_cached_migrate_pfn[1] = cc->migrate_pfn;
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