memcontrol: add vm_match_cgroup()
mm_cgroup() is exclusively used to test whether an mm's mem_cgroup pointer
is pointing to a specific cgroup. Instead of returning the pointer, we can
just do the test itself in a new macro:
vm_match_cgroup(mm, cgroup)
returns non-zero if the mm's mem_cgroup points to cgroup. Otherwise it
returns zero.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 9815951..925d57b 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -51,10 +51,8 @@
gfp_t gfp_mask);
int task_in_mem_cgroup(struct task_struct *task, const struct mem_cgroup *mem);
-static inline struct mem_cgroup *mm_cgroup(const struct mm_struct *mm)
-{
- return rcu_dereference(mm->mem_cgroup);
-}
+#define vm_match_cgroup(mm, cgroup) \
+ ((cgroup) == rcu_dereference((mm)->mem_cgroup))
extern int mem_cgroup_prepare_migration(struct page *page);
extern void mem_cgroup_end_migration(struct page *page);
@@ -123,9 +121,9 @@
return 0;
}
-static inline struct mem_cgroup *mm_cgroup(const struct mm_struct *mm)
+static inline int vm_match_cgroup(struct mm_struct *mm, struct mem_cgroup *mem)
{
- return NULL;
+ return 1;
}
static inline int task_in_mem_cgroup(struct task_struct *task,