There are some codes using for_each_zone_zonelist() even when only
iterating each node is needed. This commit introduces a new macro
for_each_node_zonelist() which iterates through valid nodes in the
zonelist.
By using this new macro, code can be written in a much simpler form.
Also, slab/slub can now skip trying to allocate from the node which was
previously tried and failed.
Co-developed-by: Ohhoon Kwon <ohkwon1043@xxxxxxxxx>
Signed-off-by: Ohhoon Kwon <ohkwon1043@xxxxxxxxx>
Signed-off-by: Donghyeok Kim <dthex5d@xxxxxxxxx>
---
include/linux/mmzone.h | 36 ++++++++++++++++++++++++++++++++++++
mm/hugetlb.c | 17 +++++++----------
mm/mmzone.c | 17 +++++++++++++++++
mm/slab.c | 7 ++-----
mm/slub.c | 8 ++++----
mm/vmscan.c | 15 ++++++---------
6 files changed, 72 insertions(+), 28 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 9aaa04ac862f..cb2ddd0b4c95 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1464,6 +1464,42 @@ static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
#define for_each_zone_zonelist(zone, z, zlist, highidx) \
for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
+
+struct zoneref *next_node_zones_zonelist(struct zoneref *z,
+ int prev_nid,
+ enum zone_type highest_zoneidx,
+ nodemask_t *nodes);
+
+/**
+ * for_each_node_zonelist_nodemask - helper macro to iterate over valid nodes in a zonelist which have at least one zone at or below a given zone index and within a nodemask
+ * @node: The current node in the iterator
+ * @z: First matched zoneref within current node
+ * @zlist: The zonelist being iterated
+ * @highidx: The zone index of the highest zone in the node
+ * @nodemask: Nodemask allowed by the allocator
+ *
+ * This iterator iterates through all nodes which have at least one zone at or below a given zone index and
+ * within a given nodemask
+ */
+#define for_each_node_zonelist_nodemask(node, z, zlist, highidx, nodemask) \
+ for (z = first_zones_zonelist(zlist, highidx, nodemask), \
+ node = zonelist_zone(z) ? zonelist_node_idx(z) : NUMA_NO_NODE; \
+ zonelist_zone(z); \
+ z = next_node_zones_zonelist(++z, node, highidx, nodemask), \
+ node = zonelist_zone(z) ? zonelist_node_idx(z) : NUMA_NO_NODE)
+
+/**
+ * for_each_node_zonelist - helper macro to iterate over nodes in a zonelist which have at least one zone at or below a given zone index
+ * @node: The current node in the iterator
+ * @z: First matched zoneref within current node
+ * @zlist: The zonelist being iterated
+ * @highidx: The zone index of the highest zone in the node
+ *
+ * This iterator iterates through all nodes which have at least one zone at or below a given zone index.
+ */
+#define for_each_node_zonelist(node, z, zlist, highidx) \
+ for_each_node_zonelist_nodemask(node, z, zlist, highidx, NULL)
+
/* Whether the 'nodes' are all movable nodes */
static inline bool movable_only_nodes(nodemask_t *nodes)
{
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index daa4bdd6c26c..283f28f1aca8 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1157,7 +1157,6 @@ static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask,
{
unsigned int cpuset_mems_cookie;
struct zonelist *zonelist;
- struct zone *zone;
struct zoneref *z;
int node = NUMA_NO_NODE;
@@ -1165,18 +1164,16 @@ static struct page *dequeue_huge_page_nodemask(struct hstate *h, gfp_t gfp_mask,
retry_cpuset:
cpuset_mems_cookie = read_mems_allowed_begin();
- for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nmask) {
+
+ /*
+ * no need to ask again on the same node. Pool is node rather than
+ * zone aware
+ */
+ for_each_node_zonelist_nodemask(node, z, zonelist, gfp_zone(gfp_mask), nmask) {
struct page *page;
- if (!cpuset_zone_allowed(zone, gfp_mask))
- continue;
- /*
- * no need to ask again on the same node. Pool is node rather than
- * zone aware
- */
- if (zone_to_nid(zone) == node)
+ if (!cpuset_node_allowed(node, gfp_mask))
continue;
- node = zone_to_nid(zone);
page = dequeue_huge_page_node_exact(h, node);
if (page)
diff --git a/mm/mmzone.c b/mm/mmzone.c
index 68e1511be12d..8b7d6286056e 100644
--- a/mm/mmzone.c
+++ b/mm/mmzone.c
@@ -72,6 +72,23 @@ struct zoneref *__next_zones_zonelist(struct zoneref *z,
return z;
}
+/* Returns the zone in the next node and at or below highest_zoneidx in a zonelist */
+struct zoneref *next_node_zones_zonelist(struct zoneref *z,
+ int prev_nid,
+ enum zone_type highest_zoneidx,
+ nodemask_t *nodes)
+{
+ if (likely(nodes == NULL))
+ while (z->zone && (zonelist_node_idx(z) == prev_nid || zonelist_zone_idx(z) > highest_zoneidx))
+ z++;
+ else
+ while (z->zone && (zonelist_node_idx(z) == prev_nid || zonelist_zone_idx(z) > highest_zoneidx ||
+ !zref_in_nodemask(z, nodes)))
+ z++;
+
+ return z;
+}
+
void lruvec_init(struct lruvec *lruvec)
{
enum lru_list lru;
diff --git a/mm/slab.c b/mm/slab.c
index a301f266efd1..b374fb88f80e 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3077,7 +3077,6 @@ static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
{
struct zonelist *zonelist;
struct zoneref *z;
- struct zone *zone;
enum zone_type highest_zoneidx = gfp_zone(flags);
void *obj = NULL;
struct slab *slab;
@@ -3096,10 +3095,8 @@ static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
* Look through allowed nodes for objects available
* from existing per node queues.
*/
- for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) {
- nid = zone_to_nid(zone);
-
- if (cpuset_zone_allowed(zone, flags) &&
+ for_each_node_zonelist(nid, z, zonelist, highest_zoneidx) {
+ if (cpuset_node_allowed(nid, flags) &&
get_node(cache, nid) &&
get_node(cache, nid)->free_objects) {
obj = ____cache_alloc_node(cache,
diff --git a/mm/slub.c b/mm/slub.c
index 6dc703488d30..3e8b4aa98b84 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -2192,7 +2192,7 @@ static void *get_any_partial(struct kmem_cache *s, gfp_t flags,
#ifdef CONFIG_NUMA
struct zonelist *zonelist;
struct zoneref *z;
- struct zone *zone;
+ int nid;
enum zone_type highest_zoneidx = gfp_zone(flags);
void *object;
unsigned int cpuset_mems_cookie;
@@ -2222,12 +2222,12 @@ static void *get_any_partial(struct kmem_cache *s, gfp_t flags,
do {
cpuset_mems_cookie = read_mems_allowed_begin();
zonelist = node_zonelist(mempolicy_slab_node(), flags);
- for_each_zone_zonelist(zone, z, zonelist, highest_zoneidx) {
+ for_each_node_zonelist(nid, z, zonelist, highest_zoneidx) {
struct kmem_cache_node *n;
- n = get_node(s, zone_to_nid(zone));
+ n = get_node(s, nid);
- if (n && cpuset_zone_allowed(zone, flags) &&
+ if (n && cpuset_node_allowed(nid, flags) &&
n->nr_partial > s->min_partial) {
object = get_partial_node(s, n, ret_slab, flags);
if (object) {
diff --git a/mm/vmscan.c b/mm/vmscan.c
index d4a7d2bd276d..f25b71bf8f61 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -6176,9 +6176,9 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
struct scan_control *sc)
{
int initial_priority = sc->priority;
- pg_data_t *last_pgdat;
+ pg_data_t *pgdat;
struct zoneref *z;
- struct zone *zone;
+ int nid;
retry:
delayacct_freepages_start();
@@ -6206,19 +6206,16 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
} while (--sc->priority >= 0);
last_pgdat = NULL;
- for_each_zone_zonelist_nodemask(zone, z, zonelist, sc->reclaim_idx,
+ for_each_node_zonelist_nodemask(nid, z, zonelist, sc->reclaim_idx,
sc->nodemask) {
- if (zone->zone_pgdat == last_pgdat)
- continue;
- last_pgdat = zone->zone_pgdat;
+ pgdat = NODE_DATA(nid);
- snapshot_refaults(sc->target_mem_cgroup, zone->zone_pgdat);
+ snapshot_refaults(sc->target_mem_cgroup, pgdat);
if (cgroup_reclaim(sc)) {
struct lruvec *lruvec;
- lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup,
- zone->zone_pgdat);
+ lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat);
clear_bit(LRUVEC_CONGESTED, &lruvec->flags);
}
}
--
2.17.1
