From 7e38b155a7b5b15f35c66d75186d6de5e5729842 Mon Sep 17 00:00:00 2001
From: David Rientjes <rientjes@google.com>
Date: Sun, 6 May 2007 14:49:32 -0700
Subject: [PATCH] --- yaml --- r: 54195 b: refs/heads/master c:
 c596d9f320aaf30d28c1d793ff3a976dee1db8f5 h: refs/heads/master i:   54193:
 b842d071e8b5c868724b8b5bf4c77ba43c1e76ae   54191:
 d4ea03e670bd2890b71bd34044486cca1eaaa683 v: v3

---
 [refs]                |  2 +-
 trunk/kernel/cpuset.c | 22 ++++++++++++++++++++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 06a7b91754c8..9eb901f22a17 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a3a02be79114b854acc555e8ed686eb84f44ae2e
+refs/heads/master: c596d9f320aaf30d28c1d793ff3a976dee1db8f5
diff --git a/trunk/kernel/cpuset.c b/trunk/kernel/cpuset.c
index f382b0f775e1..d240349cbf0f 100644
--- a/trunk/kernel/cpuset.c
+++ b/trunk/kernel/cpuset.c
@@ -2351,6 +2351,8 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  * z's node is in our tasks mems_allowed, yes.  If it's not a
  * __GFP_HARDWALL request and this zone's nodes is in the nearest
  * mem_exclusive cpuset ancestor to this tasks cpuset, yes.
+ * If the task has been OOM killed and has access to memory reserves
+ * as specified by the TIF_MEMDIE flag, yes.
  * Otherwise, no.
  *
  * If __GFP_HARDWALL is set, cpuset_zone_allowed_softwall()
@@ -2368,7 +2370,8 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  * calls get to this routine, we should just shut up and say 'yes'.
  *
  * GFP_USER allocations are marked with the __GFP_HARDWALL bit,
- * and do not allow allocations outside the current tasks cpuset.
+ * and do not allow allocations outside the current tasks cpuset
+ * unless the task has been OOM killed as is marked TIF_MEMDIE.
  * GFP_KERNEL allocations are not so marked, so can escape to the
  * nearest enclosing mem_exclusive ancestor cpuset.
  *
@@ -2392,6 +2395,7 @@ static const struct cpuset *nearest_exclusive_ancestor(const struct cpuset *cs)
  * affect that:
  *	in_interrupt - any node ok (current task context irrelevant)
  *	GFP_ATOMIC   - any node ok
+ *	TIF_MEMDIE   - any node ok
  *	GFP_KERNEL   - any node in enclosing mem_exclusive cpuset ok
  *	GFP_USER     - only nodes in current tasks mems allowed ok.
  *
@@ -2413,6 +2417,12 @@ int __cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
 	might_sleep_if(!(gfp_mask & __GFP_HARDWALL));
 	if (node_isset(node, current->mems_allowed))
 		return 1;
+	/*
+	 * Allow tasks that have access to memory reserves because they have
+	 * been OOM killed to get memory anywhere.
+	 */
+	if (unlikely(test_thread_flag(TIF_MEMDIE)))
+		return 1;
 	if (gfp_mask & __GFP_HARDWALL)	/* If hardwall request, stop here */
 		return 0;
 
@@ -2438,7 +2448,9 @@ int __cpuset_zone_allowed_softwall(struct zone *z, gfp_t gfp_mask)
  *
  * If we're in interrupt, yes, we can always allocate.
  * If __GFP_THISNODE is set, yes, we can always allocate.  If zone
- * z's node is in our tasks mems_allowed, yes.   Otherwise, no.
+ * z's node is in our tasks mems_allowed, yes.   If the task has been
+ * OOM killed and has access to memory reserves as specified by the
+ * TIF_MEMDIE flag, yes.  Otherwise, no.
  *
  * The __GFP_THISNODE placement logic is really handled elsewhere,
  * by forcibly using a zonelist starting at a specified node, and by
@@ -2462,6 +2474,12 @@ int __cpuset_zone_allowed_hardwall(struct zone *z, gfp_t gfp_mask)
 	node = zone_to_nid(z);
 	if (node_isset(node, current->mems_allowed))
 		return 1;
+        /*
+         * Allow tasks that have access to memory reserves because they have
+         * been OOM killed to get memory anywhere.
+         */
+        if (unlikely(test_thread_flag(TIF_MEMDIE)))
+                return 1;
 	return 0;
 }