mm: fix handling of panic_on_oom when cpusets are in use

The current panic_on_oom may not work if there is a process using
cpusets/mempolicy, because other nodes' memory may remain.  But some people
want failover by panic ASAP even if they are used.  This patch makes new
setting for its request.

This is tested on my ia64 box which has 3 nodes.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Ethan Solomita <solo@google.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index a35e7a8ebd7e..038d2234f139 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -413,6 +413,9 @@ void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order)
                 show_mem();
         }
 
+        if (sysctl_panic_on_oom == 2)
+                panic("out of memory. Compulsory panic_on_oom is selected.\n");
+
         cpuset_lock();
         read_lock(&tasklist_lock);