[PATCH] cpusets: swap migration interface

Add a boolean "memory_migrate" to each cpuset, represented by a file
containing "0" or "1" in each directory below /dev/cpuset.

It defaults to false (file contains "0").  It can be set true by writing
"1" to the file.

If true, then anytime that a task is attached to the cpuset so marked, the
pages of that task will be moved to that cpuset, preserving, to the extent
practical, the cpuset-relative placement of the pages.

Also anytime that a cpuset so marked has its memory placement changed (by
writing to its "mems" file), the tasks in that cpuset will have their pages
moved to the cpusets new nodes, preserving, to the extent practical, the
cpuset-relative placement of the moved pages.

Signed-off-by: Paul Jackson <pj@sgi.com>
Cc: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 3e61e829681d..66247eff24a0 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -235,6 +235,13 @@ static inline struct zonelist *huge_zonelist(struct vm_area_struct *vma,
         return NODE_DATA(0)->node_zonelists + gfp_zone(GFP_HIGHUSER);
 }
 
+static inline int do_migrate_pages(struct mm_struct *mm,
+                        const nodemask_t *from_nodes,
+                        const nodemask_t *to_nodes, int flags)
+{
+        return 0;
+}
+
 static inline void check_highest_zone(int k)
 {
 }