[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pointer, and checked for out of date cpuset-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>

1 files changed, 5 insertions, 5 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 9dea2b8a7d48..515bfeee027e 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -387,7 +387,7 @@ static int contextualize_policy(int mode, nodemask_t *nodes)
         if (!nodes)
                 return 0;
 
-        cpuset_update_current_mems_allowed();
+        cpuset_update_task_memory_state();
         if (!cpuset_nodes_subset_current_mems_allowed(*nodes))
                 return -EINVAL;
         return mpol_check_policy(mode, nodes);
@@ -461,7 +461,7 @@ long do_get_mempolicy(int *policy, nodemask_t *nmask,
         struct vm_area_struct *vma = NULL;
         struct mempolicy *pol = current->mempolicy;
 
-        cpuset_update_current_mems_allowed();
+        cpuset_update_task_memory_state();
         if (flags & ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR))
                 return -EINVAL;
         if (flags & MPOL_F_ADDR) {
@@ -1089,7 +1089,7 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
 {
         struct mempolicy *pol = get_vma_policy(current, vma, addr);
 
-        cpuset_update_current_mems_allowed();
+        cpuset_update_task_memory_state();
 
         if (unlikely(pol->policy == MPOL_INTERLEAVE)) {
                 unsigned nid;
@@ -1115,7 +1115,7 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
  *      interrupt context and apply the current process NUMA policy.
  *      Returns NULL when no page can be allocated.
  *
- *      Don't call cpuset_update_current_mems_allowed() unless
+ *      Don't call cpuset_update_task_memory_state() unless
  *      1) it's ok to take cpuset_sem (can WAIT), and
  *      2) allocating for current task (not interrupt).
  */
@@ -1124,7 +1124,7 @@ struct page *alloc_pages_current(gfp_t gfp, unsigned order)
         struct mempolicy *pol = current->mempolicy;
 
         if ((gfp & __GFP_WAIT) && !in_interrupt())
-                cpuset_update_current_mems_allowed();
+                cpuset_update_task_memory_state();
         if (!pol || in_interrupt())
                 pol = &default_policy;
         if (pol->policy == MPOL_INTERLEAVE)