From 536240f2bde98216feac87b4891d19a536b8884a Mon Sep 17 00:00:00 2001
From: Mel Gorman <mel@csn.ul.ie>
Date: Mon, 14 Dec 2009 17:59:56 -0800
Subject: [PATCH] hugetlb: abort a hugepage pool resize if a signal is pending

If a user asks for a hugepage pool resize but specified a large number,
the machine can begin trashing.  In response, they might hit ctrl-c but
signals are ignored and the pool resize continues until it fails an
allocation.  This can take a considerable amount of time so this patch
aborts a pool resize if a signal is pending.

Suggested by Dave Hansen.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 mm/hugetlb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 6df8065039eb..65f38c218207 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1278,6 +1278,9 @@ static unsigned long set_max_huge_pages(struct hstate *h, unsigned long count,
 		if (!ret)
 			goto out;
 
+		/* Bail for signals. Probably ctrl-c from user */
+		if (signal_pending(current))
+			goto out;
 	}
 
 	/*