[PATCH 1/3] hotplug cpu move tasks in empty cpusets to parent node_online_map fix

[Paul Jackson <pj@sgi.com>]

From: Paul Jackson <pj@sgi.com>

As of the October 2007 kernel/cpuset.c patch "Memoryless nodes:
Use N_HIGH_MEMORY for cpusets", cpuset nodes are relative to
the nodes with (HIGH) memory, not relative to all nodes in
node_online_map.

Signed-off-by: Paul Jackson <pj@sgi.com>
Cc: Cliff Wickman <cpw@sgi.com>

---

 kernel/cpuset.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- 2.6.24-rc6-mm1.orig/kernel/cpuset.c	2008-01-12 18:52:43.480406969 -0800
+++ 2.6.24-rc6-mm1/kernel/cpuset.c	2008-01-12 19:07:44.330236260 -0800
@@ -1817,7 +1817,8 @@ static void scan_for_empty_cpusets(const
 		cont = cp->css.cgroup;
 		/* Remove offline cpus and mems from this cpuset. */
 		cpus_and(cp->cpus_allowed, cp->cpus_allowed, cpu_online_map);
-		nodes_and(cp->mems_allowed, cp->mems_allowed, node_online_map);
+		nodes_and(cp->mems_allowed, cp->mems_allowed,
+						node_states[N_HIGH_MEMORY]);
 		if ((cpus_empty(cp->cpus_allowed) ||
 		     nodes_empty(cp->mems_allowed))) {
 		        /* Move tasks from the empty cpuset to a parent */
@@ -1832,8 +1833,8 @@ static void scan_for_empty_cpusets(const
 
 /*
  * The cpus_allowed and mems_allowed nodemasks in the top_cpuset track
- * cpu_online_map and node_online_map.  Force the top cpuset to track
- * whats online after any CPU or memory node hotplug or unplug event.
+ * cpu_online_map and node_states[N_HIGH_MEMORY].  Force the top cpuset to
+ * track what's online after any CPU or memory node hotplug or unplug event.
  *
  * Since there are two callers of this routine, one for CPU hotplug
  * events and one for memory node hotplug events, we could have coded

-- 
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                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373