[PATCH] cpuset: combine refresh_mems and update_mems

The important code paths through alloc_pages_current() and alloc_page_vma(),
by which most kernel page allocations go, both called
cpuset_update_current_mems_allowed(), which in turn called refresh_mems().
-Both- of these latter two routines did a tasklock, got the tasks cpuset
pointer, and checked for out of date cpuset->mems_generation.

That was a silly duplication of code and waste of CPU cycles on an important
code path.

Consolidated those two routines into a single routine, called
cpuset_update_task_memory_state(), since it updates more than just
mems_allowed.

Changed all callers of either routine to call the new consolidated routine.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 736d738..1feebf1 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -20,7 +20,7 @@
 extern void cpuset_exit(struct task_struct *p);
 extern cpumask_t cpuset_cpus_allowed(const struct task_struct *p);
 void cpuset_init_current_mems_allowed(void);
-void cpuset_update_current_mems_allowed(void);
+void cpuset_update_task_memory_state(void);
 #define cpuset_nodes_subset_current_mems_allowed(nodes) \
 		nodes_subset((nodes), current->mems_allowed)
 int cpuset_zonelist_valid_mems_allowed(struct zonelist *zl);
@@ -51,7 +51,7 @@
 }
 
 static inline void cpuset_init_current_mems_allowed(void) {}
-static inline void cpuset_update_current_mems_allowed(void) {}
+static inline void cpuset_update_task_memory_state(void) {}
 #define cpuset_nodes_subset_current_mems_allowed(nodes) (1)
 
 static inline int cpuset_zonelist_valid_mems_allowed(struct zonelist *zl)