From ca600aeeaea73fe9ff7cee510d3cf2304594c544 Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <borkmann@iogearbox.net>
Date: Tue, 6 Dec 2011 17:05:36 +0100
Subject: [PATCH] (offtopic) Added example app for pagefault tests

---
 opt/pft.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 opt/pft.c

diff --git a/opt/pft.c b/opt/pft.c
new file mode 100644
index 0000000..fbcef8b
--- /dev/null
+++ b/opt/pft.c
@@ -0,0 +1,53 @@
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+/* assumed more pagefaults */
+void test1(char *addr, size_t len)
+{
+	size_t i;
+	for (i = 0; i < len; ++i)
+		addr[i]++;
+}
+
+/* assumed less pagefaults */
+void test2(char *addr, size_t len)
+{
+	size_t i, pgsiz = sysconf(_SC_PAGE_SIZE);
+	for (i = 0; i < len; ++i)
+		addr[i & (pgsiz-1)]++;
+}
+
+int main(int argc, char **argv)
+{
+	int fd, ret;
+	char *addr;
+	struct stat sb;
+	if (argc != 3) {
+		printf("Usage: ./a.out <file> <test-nr:0|1>\n");
+		return -EIO;
+	}
+	fd = open(argv[1], O_RDONLY);
+	if (fd < 0)
+		return -EIO;
+	ret = fstat(fd, &sb);
+	if (ret < 0)
+		return -EIO;
+	addr = mmap(NULL, sb.st_size, PROT_READ | PROT_WRITE,
+		    MAP_PRIVATE, fd, 0);
+	if (addr == MAP_FAILED)
+		return -errno;
+	if (atoi(argv[2]) == 1)
+		test2(addr, sb.st_size);
+	else
+		test1(addr, sb.st_size);
+	munmap(addr, sb.st_size);
+	close(fd);
+	return 0;
+}
+
-- 
2.11.4.GIT