mm/demotion: drop memtier from memtype

Now that we track node-specific memtier in pg_data_t, we can drop memtier
from memtype.

Link: https://lkml.kernel.org/r/20220818131042.113280-8-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Wei Xu <weixugc@google.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Bharata B Rao <bharata@amd.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hesham Almatary <hesham.almatary@huawei.com>
Cc: Jagdish Gediya <jvgediya.oss@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/memory-tiers.h b/include/linux/memory-tiers.h
index ce9c6ba..7ca52ad 100644 (file)
--- a/include/linux/memory-tiers.h
+++ b/include/linux/memory-tiers.h
@@ -28,7 +28,6 @@ struct memory_dev_type {
        /* Nodes of same abstract distance */
        nodemask_t nodes;
        struct kref kref;
-       struct memory_tier *memtier;
 };
 
 #ifdef CONFIG_NUMA

diff --git a/mm/memory-tiers.c b/mm/memory-tiers.c
index 91fc0c3..0e2bd32 100644 (file)
--- a/mm/memory-tiers.c
+++ b/mm/memory-tiers.c
@@ -105,17 +105,22 @@ static struct memory_tier *find_create_memory_tier(struct memory_dev_type *memty
 
        lockdep_assert_held_once(&memory_tier_lock);
 
+       adistance = round_down(adistance, memtier_adistance_chunk_size);
        /*
         * If the memtype is already part of a memory tier,
         * just return that.
         */
-       if (memtype->memtier)
-               return memtype->memtier;
+       if (!list_empty(&memtype->tier_sibiling)) {
+               list_for_each_entry(memtier, &memory_tiers, list) {
+                       if (adistance == memtier->adistance_start)
+                               return memtier;
+               }
+               WARN_ON(1);
+               return ERR_PTR(-EINVAL);
+       }
 
-       adistance = round_down(adistance, memtier_adistance_chunk_size);
        list_for_each_entry(memtier, &memory_tiers, list) {
                if (adistance == memtier->adistance_start) {
-                       memtype->memtier = memtier;
                        list_add(&memtype->tier_sibiling, &memtier->memory_types);
                        return memtier;
                } else if (adistance < memtier->adistance_start) {
@@ -135,7 +140,6 @@ static struct memory_tier *find_create_memory_tier(struct memory_dev_type *memty
                list_add_tail(&new_memtier->list, &memtier->list);
        else
                list_add_tail(&new_memtier->list, &memory_tiers);
-       memtype->memtier = new_memtier;
        list_add(&memtype->tier_sibiling, &new_memtier->memory_types);
        return new_memtier;
 }
@@ -372,7 +376,6 @@ static bool clear_node_memory_tier(int node)
                node_clear(node, memtype->nodes);
                if (nodes_empty(memtype->nodes)) {
                        list_del_init(&memtype->tier_sibiling);
-                       memtype->memtier = NULL;
                        if (list_empty(&memtier->memory_types))
                                destroy_memory_tier(memtier);
                }
@@ -400,7 +403,6 @@ struct memory_dev_type *alloc_memory_type(int adistance)
        memtype->adistance = adistance;
        INIT_LIST_HEAD(&memtype->tier_sibiling);
        memtype->nodes  = NODE_MASK_NONE;
-       memtype->memtier = NULL;
        kref_init(&memtype->kref);
        return memtype;
 }