[PATCH trivial] include/linux/memcontrol.h: Clean up code only

[chengang]

From: Chen Gang <chengang@xxxxxxxxxxxxxxxx>

Merge several statements to one return statement, since the new return
statement is still simple enough.

Try to let the second line function parameters almost align with the
first line parameter (try to be within 80 columns, and in one line).

The comments can fully use 80 columns which can save one line.

Use parameter name newpage instead of new (which will be key word color
in vim) for dummy mem_cgroup_migrate(), and real mem_cgroup_migrate()
already uses newpage.

Signed-off-by: Chen Gang <gang.chen.5i5j@xxxxxxxxx>
---
 include/linux/memcontrol.h | 31 +++++++++++--------------------
 1 file changed, 11 insertions(+), 20 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 2d03975..a03204e 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -327,10 +327,7 @@ void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 
 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 {
-	if (mem_cgroup_disabled())
-		return 0;
-
-	return memcg->css.id;
+	return mem_cgroup_disabled() ? 0 : memcg->css.id;
 }
 
 /**
@@ -341,10 +338,7 @@ static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
  */
 static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
 {
-	struct cgroup_subsys_state *css;
-
-	css = css_from_id(id, &memory_cgrp_subsys);
-	return mem_cgroup_from_css(css);
+	return mem_cgroup_from_css(css_from_id(id, &memory_cgrp_subsys));
 }
 
 /**
@@ -390,9 +384,7 @@ ino_t page_cgroup_ino(struct page *page);
 
 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 {
-	if (mem_cgroup_disabled())
-		return true;
-	return !!(memcg->css.flags & CSS_ONLINE);
+	return mem_cgroup_disabled() || (memcg->css.flags & CSS_ONLINE);
 }
 
 /*
@@ -401,7 +393,7 @@ static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 int mem_cgroup_select_victim_node(struct mem_cgroup *memcg);
 
 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
-		int nr_pages);
+				int nr_pages);
 
 unsigned long mem_cgroup_node_nr_lru_pages(struct mem_cgroup *memcg,
 					   int nid, unsigned int lru_mask);
@@ -452,9 +444,8 @@ void unlock_page_memcg(struct page *page);
  * @idx: page state item to account
  * @val: number of pages (positive or negative)
  *
- * The @page must be locked or the caller must use lock_page_memcg()
- * to prevent double accounting when the page is concurrently being
- * moved to another memcg:
+ * The @page must be locked or the caller must use lock_page_memcg() to prevent
+ * double accounting when the page is concurrently being moved to another memcg:
  *
  *   lock_page(page) or lock_page_memcg(page)
  *   if (TestClearPageState(page))
@@ -462,7 +453,7 @@ void unlock_page_memcg(struct page *page);
  *   unlock_page(page) or unlock_page_memcg(page)
  */
 static inline void mem_cgroup_update_page_stat(struct page *page,
-				 enum mem_cgroup_stat_index idx, int val)
+					enum mem_cgroup_stat_index idx, int val)
 {
 	VM_BUG_ON(!(rcu_read_lock_held() || PageLocked(page)));
 
@@ -569,7 +560,7 @@ static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 {
 }
 
-static inline void mem_cgroup_migrate(struct page *old, struct page *new)
+static inline void mem_cgroup_migrate(struct page *old, struct page *newpage)
 {
 }
 
@@ -586,7 +577,7 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
 }
 
 static inline bool mm_match_cgroup(struct mm_struct *mm,
-		struct mem_cgroup *memcg)
+				   struct mem_cgroup *memcg)
 {
 	return true;
 }
@@ -798,7 +789,7 @@ static inline int memcg_cache_id(struct mem_cgroup *memcg)
  * @val: number of pages (positive or negative)
  */
 static inline void memcg_kmem_update_page_stat(struct page *page,
-				enum mem_cgroup_stat_index idx, int val)
+					enum mem_cgroup_stat_index idx, int val)
 {
 	if (memcg_kmem_enabled() && page->mem_cgroup)
 		this_cpu_add(page->mem_cgroup->stat->count[idx], val);
@@ -827,7 +818,7 @@ static inline void memcg_put_cache_ids(void)
 }
 
 static inline void memcg_kmem_update_page_stat(struct page *page,
-				enum mem_cgroup_stat_index idx, int val)
+					enum mem_cgroup_stat_index idx, int val)
 {
 }
 #endif /* CONFIG_MEMCG && !CONFIG_SLOB */
-- 
1.9.3