lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Wed, 19 Nov 2014 13:14:53 -0800
From:	Tim Bird <tim.bird@...ymobile.com>
To:	Shuah Khan <shuahkh@....samsung.com>, <linux-api@...r.kernel.org>
CC:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-embedded@...r.kernel.org" <linux-embedded@...r.kernel.org>
Subject: [PATCH] selftest: size: Add size test for Linux kernel


This test shows the amount of memory used by the system.
Note that this is dependent on the user-space that is loaded
when this program runs.  Optimally, this program would be
run as the init program itself.

The program is optimized for size itself, to avoid conflating
its own execution with that of the system software.
The code is compiled statically, with no stdlibs. On my x86_64 system,
this results in a statically linked binary of less than 5K.

Signed-off-by: Tim Bird <tim.bird@...ymobile.com>
---
 tools/testing/selftests/Makefile        |   1 +
 tools/testing/selftests/size/Makefile   |  21 +++++++
 tools/testing/selftests/size/get_size.c | 105 ++++++++++++++++++++++++++++++++
 3 files changed, 127 insertions(+)
 create mode 100644 tools/testing/selftests/size/Makefile
 create mode 100644 tools/testing/selftests/size/get_size.c

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 45f145c..fa91aef 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -15,6 +15,7 @@ TARGETS += user
 TARGETS += sysctl
 TARGETS += firmware
 TARGETS += ftrace
+TARGETS += size
 
 TARGETS_HOTPLUG = cpu-hotplug
 TARGETS_HOTPLUG += memory-hotplug
diff --git a/tools/testing/selftests/size/Makefile b/tools/testing/selftests/size/Makefile
new file mode 100644
index 0000000..51e5fbd
--- /dev/null
+++ b/tools/testing/selftests/size/Makefile
@@ -0,0 +1,21 @@
+#ifndef CC
+	CC = $(CROSS_COMPILE)gcc
+#endif
+
+#ifndef STRIP
+	STRIP = $(CROSS_COMPILE)strip
+#endif
+
+all: get_size
+
+get_size: get_size.c
+	$(CC) --static -ffreestanding -nostartfiles \
+		-Wl,--entry=main get_size.c -o get_size \
+		`cc -print-libgcc-file-name`
+	$(STRIP) -s get_size
+
+run_tests: all
+	./get_size
+
+clean:
+	$(RM) get_size
diff --git a/tools/testing/selftests/size/get_size.c b/tools/testing/selftests/size/get_size.c
new file mode 100644
index 0000000..f8ffc80
--- /dev/null
+++ b/tools/testing/selftests/size/get_size.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2014 Sony
+ *
+ * Licensed under the terms of the GNU GPL License version 2
+ *
+ * Selftest for runtime system size
+ *
+ * Prints the amount of RAM that the currently running system is using.
+ *
+ * This program tries to be as small as possible itself, to
+ * avoid perturbing the system memory utilization with its
+ * own execution.  It also attempts to have as few dependencies
+ * on kernel features as possible.
+ *
+ * It should be statically linked, with startup libs avoided.
+ * It uses no library calls, and only the following 3 syscalls:
+ *   sysinfo(), write(), and _exit()
+ *
+ * For output, it avoids printf (which in some C libraries
+ * has large external dependencies) by implementing its own
+ * strlen(), number output and print() routines.
+ */
+
+#include <sys/sysinfo.h>
+#include <unistd.h>
+
+#define STDOUT_FILENO 1
+
+my_strlen(const char *s)
+{
+	int len = 0;
+
+	while (*s++)
+		len++;
+	return len;
+}
+
+/*
+ * num_to_str - put digits from num into *s, left to right
+ *   do this by dividing the number by powers of 10
+ *   the tricky part is to omit leading zeros
+ *   don't print zeros until we've started printing any numbers at all
+ */
+static void num_to_str(unsigned long num, char *s)
+{
+	unsigned long long temp, div;
+	int started;
+
+	temp = num;
+	div = 1000000000000000000LL;
+	started = 0;
+	while (div) {
+		if (temp/div || started) {
+			*s++ = (unsigned char)(temp/div + '0');
+			started = 1;
+		}
+		temp -= (temp/div)*div;
+		div /= 10;
+	}
+	*s = 0;
+}
+
+print_num(unsigned long num)
+{
+	char num_buf[30];
+
+	num_to_str(num, num_buf);
+	write(STDOUT_FILENO, num_buf, my_strlen(num_buf));
+}
+
+print(char *s)
+{
+	write(STDOUT_FILENO, s, my_strlen(s));
+}
+
+void main(int argc, char **argv)
+{
+	int ccode;
+	unsigned long used;
+	struct sysinfo info;
+	unsigned long long temp;
+
+	print("Testing system size.\n");
+	print("1..1\n");
+
+	ccode = sysinfo(&info);
+	if (ccode < 0) {
+		print("not ok 1 get size runtime size\n");
+		print("# could not get sysinfo\n");
+		_exit(ccode);
+	}
+
+	/* ignore cache complexities for now */
+	temp = info.totalram - info.freeram - info.bufferram;
+	temp = temp * info.mem_unit;
+	temp = temp / 1024;
+
+	used = temp;
+
+	print("ok 1 get runtime size # size = ");
+	print_num(used);
+	print(" K\n");
+
+	_exit(0);
+}
-- 
1.8.2.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ