[PATCH 4/4] mm: introduce no_ksm to disable totally KSM

[Amerigo Wang <amwang@redhat.com>]

Introduce a new kernel parameter "no_ksm" to totally disable KSM.

Signed-off-by: WANG Cong <amwang@redhat.com>
---
 mm/ksm.c |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/mm/ksm.c b/mm/ksm.c
index 9a68b0c..eeb45a2 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -1984,11 +1984,24 @@ static struct attribute_group ksm_attr_group = {
 };
 #endif /* CONFIG_SYSFS */
 
+static int no_ksm;
+static int __init setup_ksm(char *str)
+{
+	no_ksm = 1;
+	return 0;
+}
+__setup("no_ksm", setup_ksm);
+
 static int __init ksm_init(void)
 {
 	struct task_struct *ksm_thread;
 	int err;
 
+	if (no_ksm) {
+		printk(KERN_INFO "ksm: disabled by cmdline\n");
+		return 0;
+	}
+
 	err = ksm_slab_init();
 	if (err)
 		goto out;
-- 
1.7.4.4