Commit 566e54e1 authored by Mel Gorman's avatar Mel Gorman Committed by Linus Torvalds
Browse files

mm, compaction: remove last_migrated_pfn from compact_control 

The last_migrated_pfn field is a bit dubious as to whether it really
helps but either way, the information from it can be inferred without
increasing the size of compact_control so remove the field.

Link: http://lkml.kernel.org/r/20190118175136.31341-4-mgorman@techsingularity.net


Signed-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c5943b9c

mm/compaction.c

+9 −16
Original line number Original line Diff line number Diff line
@@ -886,15 +886,6 @@ isolate_success: 
		cc->nr_migratepages++;

		cc->nr_migratepages++;

		nr_isolated++;

		nr_isolated++;





		/*

		 * Record where we could have freed pages by migration and not

		 * yet flushed them to buddy allocator.

		 * - this is the lowest page that was isolated and likely be

		 * then freed by migration.

		 */

		if (!cc->last_migrated_pfn)

			cc->last_migrated_pfn = low_pfn;



		/* Avoid isolating too much */

		/* Avoid isolating too much */

		if (cc->nr_migratepages == COMPACT_CLUSTER_MAX) {

		if (cc->nr_migratepages == COMPACT_CLUSTER_MAX) {

			++low_pfn;

			++low_pfn;
@@ -918,7 +909,6 @@ isolate_fail: 
			}

			}

			putback_movable_pages(&cc->migratepages);

			putback_movable_pages(&cc->migratepages);

			cc->nr_migratepages = 0;

			cc->nr_migratepages = 0;

			cc->last_migrated_pfn = 0;

			nr_isolated = 0;

			nr_isolated = 0;

		}

		}
@@ -1539,6 +1529,7 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro 
	enum compact_result ret;

	enum compact_result ret;

	unsigned long start_pfn = zone->zone_start_pfn;

	unsigned long start_pfn = zone->zone_start_pfn;

	unsigned long end_pfn = zone_end_pfn(zone);

	unsigned long end_pfn = zone_end_pfn(zone);

	unsigned long last_migrated_pfn;

	const bool sync = cc->mode != MIGRATE_ASYNC;

	const bool sync = cc->mode != MIGRATE_ASYNC;





	cc->migratetype = gfpflags_to_migratetype(cc->gfp_mask);

	cc->migratetype = gfpflags_to_migratetype(cc->gfp_mask);
@@ -1584,7 +1575,7 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro 
			cc->whole_zone = true;

			cc->whole_zone = true;

	}

	}





	cc->last_migrated_pfn = 0;

	last_migrated_pfn = 0;





	trace_mm_compaction_begin(start_pfn, cc->migrate_pfn,

	trace_mm_compaction_begin(start_pfn, cc->migrate_pfn,

				cc->free_pfn, end_pfn, sync);

				cc->free_pfn, end_pfn, sync);
@@ -1593,12 +1584,14 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro 




	while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {

	while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {

		int err;

		int err;

		unsigned long start_pfn = cc->migrate_pfn;





		switch (isolate_migratepages(zone, cc)) {

		switch (isolate_migratepages(zone, cc)) {

		case ISOLATE_ABORT:

		case ISOLATE_ABORT:

			ret = COMPACT_CONTENDED;

			ret = COMPACT_CONTENDED;

			putback_movable_pages(&cc->migratepages);

			putback_movable_pages(&cc->migratepages);

			cc->nr_migratepages = 0;

			cc->nr_migratepages = 0;

			last_migrated_pfn = 0;

			goto out;

			goto out;

		case ISOLATE_NONE:

		case ISOLATE_NONE:

			/*

			/*
@@ -1608,6 +1601,7 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro 
			 */

			 */

			goto check_drain;

			goto check_drain;

		case ISOLATE_SUCCESS:

		case ISOLATE_SUCCESS:

			last_migrated_pfn = start_pfn;

			;

			;

		}

		}
@@ -1639,8 +1633,7 @@ static enum compact_result compact_zone(struct zone *zone, struct compact_contro 
				cc->migrate_pfn = block_end_pfn(

				cc->migrate_pfn = block_end_pfn(

						cc->migrate_pfn - 1, cc->order);

						cc->migrate_pfn - 1, cc->order);

				/* Draining pcplists is useless in this case */

				/* Draining pcplists is useless in this case */

				cc->last_migrated_pfn = 0;

				last_migrated_pfn = 0;



			}

			}

		}

		}
@@ -1652,18 +1645,18 @@ check_drain: 
		 * compact_finished() can detect immediately if allocation

		 * compact_finished() can detect immediately if allocation

		 * would succeed.

		 * would succeed.

		 */

		 */

		if (cc->order > 0 && cc->last_migrated_pfn) {

		if (cc->order > 0 && last_migrated_pfn) {

			int cpu;

			int cpu;

			unsigned long current_block_start =

			unsigned long current_block_start =

				block_start_pfn(cc->migrate_pfn, cc->order);

				block_start_pfn(cc->migrate_pfn, cc->order);





			if (cc->last_migrated_pfn < current_block_start) {

			if (last_migrated_pfn < current_block_start) {

				cpu = get_cpu();

				cpu = get_cpu();

				lru_add_drain_cpu(cpu);

				lru_add_drain_cpu(cpu);

				drain_local_pages(zone);

				drain_local_pages(zone);

				put_cpu();

				put_cpu();

				/* No more flushing until we migrate again */

				/* No more flushing until we migrate again */

				cc->last_migrated_pfn = 0;

				last_migrated_pfn = 0;

			}

			}

		}

		}

mm/internal.h

+0 −1
Original line number Original line Diff line number Diff line
@@ -188,7 +188,6 @@ struct compact_control { 
	unsigned int nr_migratepages;	/* Number of pages to migrate */

	unsigned int nr_migratepages;	/* Number of pages to migrate */

	unsigned long free_pfn;		/* isolate_freepages search base */

	unsigned long free_pfn;		/* isolate_freepages search base */

	unsigned long migrate_pfn;	/* isolate_migratepages search base */

	unsigned long migrate_pfn;	/* isolate_migratepages search base */

	unsigned long last_migrated_pfn;/* Not yet flushed page being freed */

	struct zone *zone;

	struct zone *zone;

	unsigned long total_migrate_scanned;

	unsigned long total_migrate_scanned;

	unsigned long total_free_scanned;

	unsigned long total_free_scanned;

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