[PATCH linux-next v2] ksm: add ksm involvement information for each process

[xu.xin16]

From: xu xin <xu.xin16@xxxxxxxxxx>

In /proc/<pid>/ksm_stat, Add two extra ksm involvement items including
MMF_VM_MERGEABLE and MMF_VM_MERGE_ANY. It helps administrators to
better know the system's KSM behavior at process level.

KSM_mergeable: yes/no
	whether the process'mm is added by madvise() into the candidate list
	of KSM or not.
KSM_merge_any: yes/no
	whether the process'mm is added by prctl() into the candidate list
	of KSM or not, and fully enabled at process level.

Changelog
=========
v1 -> v2:
	replace the internal flag names with straightforward strings.
	* MMF_VM_MERGEABLE -> KSM_mergeable
	* MMF_VM_MERGE_ANY -> KSM_merge_any

Signed-off-by: xu xin <xu.xin16@xxxxxxxxxx>
---
 fs/proc/base.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 18550c071d71..50e808ffcda4 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3217,6 +3217,10 @@ static int proc_pid_ksm_stat(struct seq_file *m, struct pid_namespace *ns,
 		seq_printf(m, "ksm_zero_pages %lu\n", mm->ksm_zero_pages);
 		seq_printf(m, "ksm_merging_pages %lu\n", mm->ksm_merging_pages);
 		seq_printf(m, "ksm_process_profit %ld\n", ksm_process_profit(mm));
+		seq_printf(m, "KSM_mergeable: %s\n",
+				test_bit(MMF_VM_MERGEABLE, &mm->flags) ? "yes" : "no");
+		seq_printf(m, "KSM_merge_any: %s\n",
+				test_bit(MMF_VM_MERGE_ANY, &mm->flags) ? "yes" : "no");
 		mmput(mm);
 	}

-- 
2.15.2