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Diffstat (limited to 'mm')
-rw-r--r--mm/hugetlb.c7
-rw-r--r--mm/memcontrol.c15
2 files changed, 18 insertions, 4 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 039ddbc574e9..3103099f64fd 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3167,6 +3167,13 @@ static vm_fault_t hugetlb_vm_op_fault(struct vm_fault *vmf)
return 0;
}
+/*
+ * When a new function is introduced to vm_operations_struct and added
+ * to hugetlb_vm_ops, please consider adding the function to shm_vm_ops.
+ * This is because under System V memory model, mappings created via
+ * shmget/shmat with "huge page" specified are backed by hugetlbfs files,
+ * their original vm_ops are overwritten with shm_vm_ops.
+ */
const struct vm_operations_struct hugetlb_vm_ops = {
.fault = hugetlb_vm_op_fault,
.open = hugetlb_vm_op_open,
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 8c0280b3143e..b2173f7e5164 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4037,6 +4037,14 @@ static struct cftype mem_cgroup_legacy_files[] = {
static DEFINE_IDR(mem_cgroup_idr);
+static void mem_cgroup_id_remove(struct mem_cgroup *memcg)
+{
+ if (memcg->id.id > 0) {
+ idr_remove(&mem_cgroup_idr, memcg->id.id);
+ memcg->id.id = 0;
+ }
+}
+
static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n)
{
VM_BUG_ON(atomic_read(&memcg->id.ref) <= 0);
@@ -4047,8 +4055,7 @@ static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n)
{
VM_BUG_ON(atomic_read(&memcg->id.ref) < n);
if (atomic_sub_and_test(n, &memcg->id.ref)) {
- idr_remove(&mem_cgroup_idr, memcg->id.id);
- memcg->id.id = 0;
+ mem_cgroup_id_remove(memcg);
/* Memcg ID pins CSS */
css_put(&memcg->css);
@@ -4185,8 +4192,7 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
idr_replace(&mem_cgroup_idr, memcg, memcg->id.id);
return memcg;
fail:
- if (memcg->id.id > 0)
- idr_remove(&mem_cgroup_idr, memcg->id.id);
+ mem_cgroup_id_remove(memcg);
__mem_cgroup_free(memcg);
return NULL;
}
@@ -4245,6 +4251,7 @@ mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
return &memcg->css;
fail:
+ mem_cgroup_id_remove(memcg);
mem_cgroup_free(memcg);
return ERR_PTR(-ENOMEM);
}