From: Lee Schermerhorn <lee.schermerhorn@hp.com>
Date: Tue, 23 Mar 2010 20:35:41 +0000 (-0700)
Subject: mempolicy: fix get_mempolicy() for relative and static nodes
X-Git-Tag: v2.6.34-rc3~52
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=c6b6ef8bb05af632889c5536513b9f4004961f73;p=linux.git

mempolicy: fix get_mempolicy() for relative and static nodes

Discovered while testing other mempolicy changes:

get_mempolicy() does not handle static/relative mode flags correctly.
Return the value that the user specified so that it can be restored
via set_mempolicy() if desired.

Signed-off-by: Lee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 6cdfa1df57f6..8034abd3a135 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -806,9 +806,13 @@ static long do_get_mempolicy(int *policy, nodemask_t *nmask,
 
 	err = 0;
 	if (nmask) {
-		task_lock(current);
-		get_policy_nodemask(pol, nmask);
-		task_unlock(current);
+		if (mpol_store_user_nodemask(pol)) {
+			*nmask = pol->w.user_nodemask;
+		} else {
+			task_lock(current);
+			get_policy_nodemask(pol, nmask);
+			task_unlock(current);
+		}
 	}
 
  out: