With memory tiers support we can have memory only NUMA nodes
in the top tier from which we want to avoid promotion tracking NUMA
faults. Update node_is_toptier to work with memory tiers.
All NUMA nodes are by default top tier nodes. With lower memory
tiers added we consider all memory tiers above a memory tier having
CPU NUMA nodes as a top memory tier
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
---
include/linux/memory-tiers.h | 6 ++++++
include/linux/node.h | 5 -----
mm/huge_memory.c | 1 +
mm/memory-tiers.c | 41 ++++++++++++++++++++++++++++++++++++
mm/migrate.c | 1 +
mm/mprotect.c | 1 +
6 files changed, 50 insertions(+), 5 deletions(-)
diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h
index 8137e9322603..0e5591ddc74b 100644
--- a/include/linux/memory-tiers.h
+++ b/include/linux/memory-tiers.h
@@ -31,6 +31,7 @@ static inline void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *target
*targets = NODE_MASK_NONE;
}
#endif /* CONFIG_MIGRATION */
+bool node_is_toptier(int node);
#else
@@ -49,5 +50,10 @@ static inline void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *target
{
*targets = NODE_MASK_NONE;
}
+
+static inline bool node_is_toptier(int node)
+{
+ return true;
+}
#endif /* CONFIG_NUMA */
#endif /* _LINUX_MEMORY_TIERS_H */
diff --git a/include/linux/node.h b/include/linux/node.h
index 40d641a8bfb0..9ec680dd607f 100644
--- a/include/linux/node.h
+++ b/include/linux/node.h
@@ -185,9 +185,4 @@ static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
#define to_node(device) container_of(device, struct node, dev)
-static inline bool node_is_toptier(int node)
-{
- return node_state(node, N_CPU);
-}
-
#endif /* _LINUX_NODE_H_ */
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 834f288b3769..8405662646e9 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -35,6 +35,7 @@
#include <linux/numa.h>
#include <linux/page_owner.h>
#include <linux/sched/sysctl.h>
+#include <linux/memory-tiers.h>
#include <asm/tlb.h>
#include <asm/pgalloc.h>
diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
index 98e55600f250..923b056e222c 100644
--- a/mm/memory-tiers.c
+++ b/mm/memory-tiers.c
@@ -26,6 +26,7 @@ struct demotion_nodes {
static void establish_migration_targets(void);
static DEFINE_MUTEX(memory_tier_lock);
static LIST_HEAD(memory_tiers);
+static int top_tier_id;
/*
* node_demotion[] examples:
*
@@ -268,6 +269,31 @@ static int node_set_memory_tier(int node, int tier)
return ret;
}
+bool node_is_toptier(int node)
+{
+ bool toptier;
+ pg_data_t *pgdat;
+ struct memory_tier *memtier;
+
+ pgdat = NODE_DATA(node);
+ if (!pgdat)
+ return false;
+
+ rcu_read_lock();
+ memtier = rcu_dereference(pgdat->memtier);
+ if (!memtier) {
+ toptier = true;
+ goto out;
+ }
+ if (memtier->id >= top_tier_id)
+ toptier = true;
+ else
+ toptier = false;
+out:
+ rcu_read_unlock();
+ return toptier;
+}
+
#ifdef CONFIG_MIGRATION
void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets)
{
@@ -440,6 +466,21 @@ static void establish_migration_targets(void)
} while (1);
}
build_lower_tier_mask:
+ /*
+ * Promotion is allowed from a memory tier to higher
+ * memory tier only if the memory tier doesn't include
+ * compute. We want to skip promotion from a memory tier,
+ * if any node that is part of the memory tier have CPUs.
+ * Once we detect such a memory tier, we consider that tier
+ * as top tiper from which promotion is not allowed.
+ */
+ list_for_each_entry_reverse(memtier, &memory_tiers, list) {
+ nodes_and(used, node_states[N_CPU], memtier->nodelist);
+ if (!nodes_empty(used)) {
+ top_tier_id = memtier->id;
+ break;
+ }
+ }
/*
* Now build the lower_tier mask for each node collecting node mask from
* all memory tier below it. This allows us to fallback demotion page
diff --git a/mm/migrate.c b/mm/migrate.c
index c758c9c21d7d..1da81136eaaa 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -50,6 +50,7 @@
#include <linux/memory.h>
#include <linux/random.h>
#include <linux/sched/sysctl.h>
+#include <linux/memory-tiers.h>
#include <asm/tlbflush.h>
diff --git a/mm/mprotect.c b/mm/mprotect.c
index ba5592655ee3..92a2fc0fa88b 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -31,6 +31,7 @@
#include <linux/pgtable.h>
#include <linux/sched/sysctl.h>
#include <linux/userfaultfd_k.h>
+#include <linux/memory-tiers.h>
#include <asm/cacheflush.h>
#include <asm/mmu_context.h>
#include <asm/tlbflush.h>
--
2.36.1
