#endif
#if defined CONFIG_COMPACTION || defined CONFIG_CMA
-#ifdef CONFIG_TRACEPOINTS
-static const char *const compaction_status_string[] = {
- "deferred",
- "skipped",
- "continue",
- "partial",
- "complete",
- "no_suitable_page",
- "not_suitable_zone",
-};
-#endif
#define CREATE_TRACE_POINTS
#include <trace/events/compaction.h>
/* 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);
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;
}
}
return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE;
}
+/*
+ * order == -1 is expected when compacting via
+ * /proc/sys/vm/compact_memory
+ */
+static inline bool is_via_compact_memory(int order)
+{
+ return order == -1;
+}
+
static int __compact_finished(struct zone *zone, struct compact_control *cc,
const int migratetype)
{
unsigned long watermark;
if (cc->contended || fatal_signal_pending(current))
- return COMPACT_PARTIAL;
+ return COMPACT_CONTENDED;
/* Compaction run completes if the migrate and free scanner meet */
if (compact_scanners_met(cc)) {
return COMPACT_COMPLETE;
}
- /*
- * order == -1 is expected when compacting via
- * /proc/sys/vm/compact_memory
- */
- if (cc->order == -1)
+ if (is_via_compact_memory(cc->order))
return COMPACT_CONTINUE;
/* Compaction run is not finished if the watermark is not met */
int fragindex;
unsigned long watermark;
- /*
- * order == -1 is expected when compacting via
- * /proc/sys/vm/compact_memory
- */
- if (order == -1)
+ if (is_via_compact_memory(order))
return COMPACT_CONTINUE;
watermark = low_wmark_pages(zone);
switch (isolate_migratepages(zone, cc)) {
case ISOLATE_ABORT:
- ret = COMPACT_PARTIAL;
+ ret = COMPACT_CONTENDED;
putback_movable_pages(&cc->migratepages);
cc->nr_migratepages = 0;
goto out;
* and we want compact_finished() to detect it
*/
if (err == -ENOMEM && !compact_scanners_met(cc)) {
- ret = COMPACT_PARTIAL;
+ ret = COMPACT_CONTENDED;
goto out;
}
}
trace_mm_compaction_end(start_pfn, cc->migrate_pfn,
cc->free_pfn, end_pfn, sync, ret);
+ if (ret == COMPACT_CONTENDED)
+ ret = COMPACT_PARTIAL;
+
return ret;
}
* this makes sure we compact the whole zone regardless of
* cached scanner positions.
*/
- if (cc->order == -1)
+ if (is_via_compact_memory(cc->order))
__reset_isolation_suitable(zone);
- if (cc->order == -1 || !compaction_deferred(zone, cc->order))
+ if (is_via_compact_memory(cc->order) ||
+ !compaction_deferred(zone, cc->order))
compact_zone(zone, cc);
if (cc->order > 0) {