[PATCH 08/15] task_diag: Only add VMAs for thread_group leader

[Andrey Vagin]

From: David Ahern <dsahern@xxxxxxxxx>

threads of a process share the same VMAs, so when dumping all threads
for all processes only push vma data for group leader.

Signed-off-by: David Ahern <dsahern@xxxxxxxxx>
Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
---
 fs/proc/task_diag.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/fs/proc/task_diag.c b/fs/proc/task_diag.c
index e0f0b03..00db32d 100644
--- a/fs/proc/task_diag.c
+++ b/fs/proc/task_diag.c
@@ -433,7 +433,17 @@ static int task_diag_fill(struct task_struct *tsk, struct sk_buff *skb,
 	}
 
 	if (show_flags & TASK_DIAG_SHOW_VMA) {
-		if (i >= n)
+		bool dump_vma = true;
+
+		/* if the request is to dump all threads of all processes
+		 * only show VMAs for group leader.
+		 */
+		if ((req->dump_strategy == TASK_DIAG_DUMP_ALL_THREAD ||
+		     req->dump_strategy == TASK_DIAG_DUMP_THREAD) &&
+		    !thread_group_leader(tsk))
+			dump_vma = false;
+
+		if (dump_vma && i >= n)
 			err = fill_vma(tsk, skb, cb, &progress, show_flags);
 		if (err)
 			goto err;
-- 
2.5.5