diff options
Diffstat (limited to 'mm/memory-tiers.c')
| -rw-r--r-- | mm/memory-tiers.c | 51 |
1 files changed, 48 insertions, 3 deletions
diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c index 0e2bd32375d6..45dd6fa4e2d1 100644 --- a/mm/memory-tiers.c +++ b/mm/memory-tiers.c @@ -4,7 +4,6 @@ #include <linux/sysfs.h> #include <linux/kobject.h> #include <linux/memory.h> -#include <linux/mmzone.h> #include <linux/memory-tiers.h> #include "internal.h" @@ -20,6 +19,8 @@ struct memory_tier { * adistance_start .. adistance_start + MEMTIER_CHUNK_SIZE */ int adistance_start; + /* All the nodes that are part of all the lower memory tiers. */ + nodemask_t lower_tier_mask; }; struct demotion_nodes { @@ -161,6 +162,24 @@ static struct memory_tier *__node_get_memory_tier(int node) } #ifdef CONFIG_MIGRATION +void node_get_allowed_targets(pg_data_t *pgdat, nodemask_t *targets) +{ + struct memory_tier *memtier; + + /* + * pg_data_t.memtier updates includes a synchronize_rcu() + * which ensures that we either find NULL or a valid memtier + * in NODE_DATA. protect the access via rcu_read_lock(); + */ + rcu_read_lock(); + memtier = rcu_dereference(pgdat->memtier); + if (memtier) + *targets = memtier->lower_tier_mask; + else + *targets = NODE_MASK_NONE; + rcu_read_unlock(); +} + /** * next_demotion_node() - Get the next node in the demotion path * @node: The starting node to lookup the next node @@ -208,10 +227,19 @@ int next_demotion_node(int node) static void disable_all_demotion_targets(void) { + struct memory_tier *memtier; int node; - for_each_node_state(node, N_MEMORY) + for_each_node_state(node, N_MEMORY) { node_demotion[node].preferred = NODE_MASK_NONE; + /* + * We are holding memory_tier_lock, it is safe + * to access pgda->memtier. + */ + memtier = __node_get_memory_tier(node); + if (memtier) + memtier->lower_tier_mask = NODE_MASK_NONE; + } /* * Ensure that the "disable" is visible across the system. * Readers will see either a combination of before+disable @@ -243,7 +271,7 @@ static void establish_demotion_targets(void) struct demotion_nodes *nd; int target = NUMA_NO_NODE, node; int distance, best_distance; - nodemask_t tier_nodes; + nodemask_t tier_nodes, lower_tier; lockdep_assert_held_once(&memory_tier_lock); @@ -291,6 +319,23 @@ static void establish_demotion_targets(void) } } while (1); } + /* + * 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 + * allocation to a set of nodes that is closer the above selected + * perferred node. + */ + lower_tier = node_states[N_MEMORY]; + list_for_each_entry(memtier, &memory_tiers, list) { + /* + * Keep removing current tier from lower_tier nodes, + * This will remove all nodes in current and above + * memory tier from the lower_tier mask. + */ + tier_nodes = get_memtier_nodemask(memtier); + nodes_andnot(lower_tier, lower_tier, tier_nodes); + memtier->lower_tier_mask = lower_tier; + } } #else |