[LTP] [PATCH] Stack size mapping is decreased through mlock/munlock call

[<ca...@re...>]

- mlock all lines on /proc/self/maps
- show mapping
- munlock all lines on /proc/self/maps
- show again

Signed-off-by: CAI Qian <ca...@re...>
---
 runtest/mm                                |    1 +
 testcases/kernel/syscalls/mlock/mlock03.c |  106 +++++++++++++++++++++++++++++
 2 files changed, 107 insertions(+), 0 deletions(-)
 create mode 100644 testcases/kernel/syscalls/mlock/mlock03.c

diff --git a/runtest/mm b/runtest/mm
index 16e60d4..09a339d 100644
--- a/runtest/mm
+++ b/runtest/mm
@@ -70,3 +70,4 @@ hugemmap05_3 hugemmap05 -s -m
 cpuset01 cpuset01 -I 3600
 
 mbind01 mbind01
+mlock01 mlock01 -i 20
diff --git a/testcases/kernel/syscalls/mlock/mlock03.c b/testcases/kernel/syscalls/mlock/mlock03.c
new file mode 100644
index 0000000..7e66053
--- /dev/null
+++ b/testcases/kernel/syscalls/mlock/mlock03.c
@@ -0,0 +1,106 @@
+/*
+ * Stack size mapping is decreased through mlock/munlock call.
+ *
+ * - mlock all lines on /proc/self/maps
+ * - show mapping
+ * - munlock all lines on /proc/self/maps
+ * - show again
+ *
+ * Copyright (C) 2010  Red Hat, Inc.
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Further, this software is distributed without any warranty that it
+ * is free of the rightful claim of any third person regarding
+ * infringement or the like.  Any license provided herein, whether
+ * implied or otherwise, applies only to this software file.  Patent
+ * licenses, if any, provided herein do not apply to combinations of
+ * this program with other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+#include "test.h"
+#include "usctest.h"
+
+#define KB 1024
+
+char *TCID = "mlock03";
+int TST_TOTAL = 1;
+extern int Tst_count;
+
+int main(int argc, char *argv[])
+{
+	int lc;
+	char *msg;
+	long from, to, first = -1, last = -1;
+	char b[KB], pid[BUFSIZ];
+	FILE *fp;
+
+	msg = parse_opts(argc, argv, NULL, NULL);
+	if (msg != NULL)
+		tst_brkm(TBROK, tst_exit, "OPTION PARSING ERROR - %s",
+			msg);
+	sprintf(pid, "cat /proc/%d/maps", getpid());
+
+	for (lc = 0; TEST_LOOPING(lc); lc++) {
+		fp = fopen("/proc/self/maps", "r");
+		if (fp == NULL)
+			tst_brkm(TBROK|TERRNO, tst_exit, "fopen");
+
+		while (!feof(fp)) {
+			if (!fgets(b, KB - 1, fp))
+				break;
+			b[strlen(b) - 1] = '\0';
+			sscanf(b, "%lx-%lx", &from, &to);
+
+			/* Record the initial stack size. */
+			if ((lc == 0) && (strstr(b, "[stack]") != NULL))
+				first = (to - from)/KB;
+
+			switch (lc & 1) {
+			case 0:
+				if (mlock((const void*)from,
+						(to - from)) == -1)
+					tst_resm(TINFO|TERRNO, "mlock");
+				break;
+			case 1:
+				if (munlock((const void*)from,
+						(to - from)) == -1)
+					tst_resm(TINFO|TERRNO,
+						"munlock");
+				break;
+			default:
+				break;
+			}
+			tst_resm(TINFO, "%s from %lx to %0lx",
+				(lc&1) ? "munlock" : "mlock  ",
+				from, to);
+
+			/* Record the final stack size. */
+			if (strstr(b, "[stack]") != NULL)
+				last = (to - from)/KB;
+		}
+		printf("\n");
+		fclose(fp);
+	}
+	tst_resm(TINFO, "starting stack size is %ld", first);
+	tst_resm(TINFO, "final stack size is %ld", last);
+
+	if (last < first)
+		tst_resm(TFAIL, "stack size is decreased.");
+	else
+		tst_resm(TPASS, "stack size is not decreased.");
+		
+	tst_exit();
+}
-- 
1.7.1