Instead of define an index and determining if the zone has memory, introduce for_each_populated_zone_pgdat() helper that can be used to iterate over each populated zone in pgdat, and convert the most obvious users to it. This patch has no functional change. Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx> --- drivers/base/memory.c | 7 ++----- include/linux/mmzone.h | 8 ++++++++ mm/compaction.c | 36 +++++++----------------------------- mm/page-writeback.c | 8 ++------ 4 files changed, 19 insertions(+), 40 deletions(-) diff --git a/drivers/base/memory.c b/drivers/base/memory.c index b456ac213610..ad898b1c85c7 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -656,7 +656,6 @@ static struct zone *early_node_zone_for_memory_block(struct memory_block *mem, const unsigned long nr_pages = PAGES_PER_SECTION * sections_per_block; struct zone *zone, *matching_zone = NULL; pg_data_t *pgdat = NODE_DATA(nid); - int i; /* * This logic only works for early memory, when the applicable zones @@ -666,10 +665,8 @@ static struct zone *early_node_zone_for_memory_block(struct memory_block *mem, * zones that intersect with the memory block are actually applicable. * No need to look at the memmap. */ - for (i = 0; i < MAX_NR_ZONES; i++) { - zone = pgdat->node_zones + i; - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { + if (!zone_intersects(zone, start_pfn, nr_pages)) continue; if (!matching_zone) { diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index a4889c9d4055..48e9f01c0b5d 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1580,6 +1580,14 @@ extern struct zone *next_zone(struct zone *zone); ; /* do nothing */ \ else +#define for_each_populated_zone_pgdat(zone, pgdat, max) \ + for (zone = pgdat->node_zones; \ + zone < pgdat->node_zones + max; \ + zone++) \ + if (!populated_zone(zone)) \ + ; /* do nothing */ \ + else + static inline struct zone *zonelist_zone(struct zoneref *zoneref) { return zoneref->zone; diff --git a/mm/compaction.c b/mm/compaction.c index c8bcdea15f5f..863f10c7e510 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -375,12 +375,9 @@ static void __reset_isolation_suitable(struct zone *zone) void reset_isolation_suitable(pg_data_t *pgdat) { - int zoneid; + struct zone *zone; - for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) { - struct zone *zone = &pgdat->node_zones[zoneid]; - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { /* Only flush if a full compaction finished recently */ if (zone->compact_blockskip_flush) @@ -2046,14 +2043,10 @@ static unsigned int fragmentation_score_zone_weighted(struct zone *zone) static unsigned int fragmentation_score_node(pg_data_t *pgdat) { unsigned int score = 0; - int zoneid; + struct zone *zone; - for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) { - struct zone *zone; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { - zone = &pgdat->node_zones[zoneid]; - if (!populated_zone(zone)) - continue; score += fragmentation_score_zone_weighted(zone); } @@ -2681,7 +2674,6 @@ enum compact_result try_to_compact_pages(gfp_t gfp_mask, unsigned int order, */ static void proactive_compact_node(pg_data_t *pgdat) { - int zoneid; struct zone *zone; struct compact_control cc = { .order = -1, @@ -2692,10 +2684,7 @@ static void proactive_compact_node(pg_data_t *pgdat) .proactive_compaction = true, }; - for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) { - zone = &pgdat->node_zones[zoneid]; - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { cc.zone = zone; @@ -2712,7 +2701,6 @@ static void proactive_compact_node(pg_data_t *pgdat) static void compact_node(int nid) { pg_data_t *pgdat = NODE_DATA(nid); - int zoneid; struct zone *zone; struct compact_control cc = { .order = -1, @@ -2722,12 +2710,7 @@ static void compact_node(int nid) .gfp_mask = GFP_KERNEL, }; - - for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) { - - zone = &pgdat->node_zones[zoneid]; - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { cc.zone = zone; @@ -2823,15 +2806,10 @@ static inline bool kcompactd_work_requested(pg_data_t *pgdat) static bool kcompactd_node_suitable(pg_data_t *pgdat) { - int zoneid; struct zone *zone; enum zone_type highest_zoneidx = pgdat->kcompactd_highest_zoneidx; - for (zoneid = 0; zoneid <= highest_zoneidx; zoneid++) { - zone = &pgdat->node_zones[zoneid]; - - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, highest_zoneidx + 1) { if (compaction_suitable(zone, pgdat->kcompactd_max_order, 0, highest_zoneidx) == COMPACT_CONTINUE) diff --git a/mm/page-writeback.c b/mm/page-writeback.c index db7943999007..9a7bcf8fdfd5 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -272,13 +272,9 @@ static void wb_min_max_ratio(struct bdi_writeback *wb, static unsigned long node_dirtyable_memory(struct pglist_data *pgdat) { unsigned long nr_pages = 0; - int z; + struct zone *zone; - for (z = 0; z < MAX_NR_ZONES; z++) { - struct zone *zone = pgdat->node_zones + z; - - if (!populated_zone(zone)) - continue; + for_each_populated_zone_pgdat(zone, pgdat, MAX_NR_ZONES) { nr_pages += zone_page_state(zone, NR_FREE_PAGES); } -- 2.25.1