mm: fix kerneldoc on mem_cgroup_replace_page

[linux-2.6-block.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 9acfb165eb52eeff2271888ec61fe093c9015641..e234c21a5e6cb3d02104da2422548692fda1e881 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2128,7 +2128,7 @@ done_restock:
         */
        do {
                if (page_counter_read(&memcg->memory) > memcg->high) {
-                       current->memcg_nr_pages_over_high += nr_pages;
+                       current->memcg_nr_pages_over_high += batch;
                        set_notify_resume(current);
                        break;
                }
@@ -4779,23 +4779,18 @@ static void mem_cgroup_clear_mc(void)
        spin_unlock(&mc.lock);
 }
 
-static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
-                                struct cgroup_taskset *tset)
+static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
 {
-       struct mem_cgroup *memcg = mem_cgroup_from_css(css);
+       struct cgroup_subsys_state *css;
+       struct mem_cgroup *memcg;
        struct mem_cgroup *from;
        struct task_struct *leader, *p;
        struct mm_struct *mm;
        unsigned long move_flags;
        int ret = 0;
 
-       /*
-        * We are now commited to this value whatever it is. Changes in this
-        * tunable will only affect upcoming migrations, not the current one.
-        * So we need to save it, and keep it going.
-        */
-       move_flags = READ_ONCE(memcg->move_charge_at_immigrate);
-       if (!move_flags)
+       /* charge immigration isn't supported on the default hierarchy */
+       if (cgroup_subsys_on_dfl(memory_cgrp_subsys))
                return 0;
 
        /*
@@ -4805,13 +4800,23 @@ static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
         * multiple.
         */
        p = NULL;
-       cgroup_taskset_for_each_leader(leader, tset) {
+       cgroup_taskset_for_each_leader(leader, css, tset) {
                WARN_ON_ONCE(p);
                p = leader;
+               memcg = mem_cgroup_from_css(css);
        }
        if (!p)
                return 0;
 
+       /*
+        * We are now commited to this value whatever it is. Changes in this
+        * tunable will only affect upcoming migrations, not the current one.
+        * So we need to save it, and keep it going.
+        */
+       move_flags = READ_ONCE(memcg->move_charge_at_immigrate);
+       if (!move_flags)
+               return 0;
+
        from = mem_cgroup_from_task(p);
 
        VM_BUG_ON(from == memcg);
@@ -4842,8 +4847,7 @@ static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
        return ret;
 }
 
-static void mem_cgroup_cancel_attach(struct cgroup_subsys_state *css,
-                                    struct cgroup_taskset *tset)
+static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
 {
        if (mc.to)
                mem_cgroup_clear_mc();
@@ -4985,10 +4989,10 @@ retry:
        atomic_dec(&mc.from->moving_account);
 }
 
-static void mem_cgroup_move_task(struct cgroup_subsys_state *css,
-                                struct cgroup_taskset *tset)
+static void mem_cgroup_move_task(struct cgroup_taskset *tset)
 {
-       struct task_struct *p = cgroup_taskset_first(tset);
+       struct cgroup_subsys_state *css;
+       struct task_struct *p = cgroup_taskset_first(tset, &css);
        struct mm_struct *mm = get_task_mm(p);
 
        if (mm) {
@@ -5000,17 +5004,14 @@ static void mem_cgroup_move_task(struct cgroup_subsys_state *css,
                mem_cgroup_clear_mc();
 }
 #else  /* !CONFIG_MMU */
-static int mem_cgroup_can_attach(struct cgroup_subsys_state *css,
-                                struct cgroup_taskset *tset)
+static int mem_cgroup_can_attach(struct cgroup_taskset *tset)
 {
        return 0;
 }
-static void mem_cgroup_cancel_attach(struct cgroup_subsys_state *css,
-                                    struct cgroup_taskset *tset)
+static void mem_cgroup_cancel_attach(struct cgroup_taskset *tset)
 {
 }
-static void mem_cgroup_move_task(struct cgroup_subsys_state *css,
-                                struct cgroup_taskset *tset)
+static void mem_cgroup_move_task(struct cgroup_taskset *tset)
 {
 }
 #endif
@@ -5511,11 +5512,11 @@ void mem_cgroup_uncharge_list(struct list_head *page_list)
  * mem_cgroup_replace_page - migrate a charge to another page
  * @oldpage: currently charged page
  * @newpage: page to transfer the charge to
- * @lrucare: either or both pages might be on the LRU already
  *
  * Migrate the charge from @oldpage to @newpage.
  *
  * Both pages must be locked, @newpage->mapping must be set up.
+ * Either or both pages might be on the LRU already.
  */
 void mem_cgroup_replace_page(struct page *oldpage, struct page *newpage)
 {