Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751363AbaLCSm3 (ORCPT ); Wed, 3 Dec 2014 13:42:29 -0500 Received: from seldrel01.sonyericsson.com ([212.209.106.2]:11255 "EHLO seldrel01.sonyericsson.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751104AbaLCSm1 (ORCPT ); Wed, 3 Dec 2014 13:42:27 -0500 Message-ID: <547F598D.7030205@sonymobile.com> Date: Wed, 3 Dec 2014 10:42:21 -0800 From: Tim Bird User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Shuah Khan , "linux-api@vger.kernel.org" CC: Thomas Petazzoni , Michael Ellerman , "linux-embedded@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Josh Triplett Subject: [PATCH v6] selftest: size: Add size test for Linux kernel Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- Changes from v5: - remove #ifdef in Makefile (doh!) - use variables in build command - use different num_to_str, with less conversions Changes from v4: - make most routines static - replace strip with gcc -s - remove explicit reference to _start - change --static to -static - remove explicit reference to LIBGCC - fix test description for ok and not ok paths, for test 1 Changes from v3: - add more human-readable output - put libgcc reference into a variable in Makefile Changes from v2: - fix copyright string (again!) - use __builtin_strlen instead of my own strlen - replace main with _start Changes from v1: - add return values to print routines - add .gitignore file - use more correct Copyright string in get_size.c tools/testing/selftests/Makefile | 1 + tools/testing/selftests/size/.gitignore | 1 + tools/testing/selftests/size/Makefile | 12 ++++ tools/testing/selftests/size/get_size.c | 100 ++++++++++++++++++++++++++++++++ 4 files changed, 114 insertions(+) create mode 100644 tools/testing/selftests/size/.gitignore 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/.gitignore b/tools/testing/selftests/size/.gitignore new file mode 100644 index 0000000..189b781 --- /dev/null +++ b/tools/testing/selftests/size/.gitignore @@ -0,0 +1 @@ +get_size diff --git a/tools/testing/selftests/size/Makefile b/tools/testing/selftests/size/Makefile new file mode 100644 index 0000000..04dc25e --- /dev/null +++ b/tools/testing/selftests/size/Makefile @@ -0,0 +1,12 @@ +CC = $(CROSS_COMPILE)gcc + +all: get_size + +get_size: get_size.c + $(CC) -static -ffreestanding -nostartfiles -s $< -o $@ + +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..2d1af7c --- /dev/null +++ b/tools/testing/selftests/size/get_size.c @@ -0,0 +1,100 @@ +/* + * Copyright 2014 Sony Mobile Communications Inc. + * + * 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 it's own + * number output and print routines, and using __builtin_strlen() + */ + +#include +#include + +#define STDOUT_FILENO 1 + +static int print(const char *s) +{ + return write(STDOUT_FILENO, s, __builtin_strlen(s)); +} + +static inline char *num_to_str(unsigned long num, char *buf, int len) +{ + unsigned int digit; + + /* put digits in buffer from back to front */ + buf += len - 1; + *buf = 0; + do { + digit = num % 10; + *(--buf) = digit + '0'; + num /= 10; + } while (num > 0); + + return buf; +} + +static int print_num(unsigned long num) +{ + char num_buf[30]; + + return print(num_to_str(num, num_buf, sizeof(num_buf))); +} + +static int print_k_value(const char *s, unsigned long num, unsigned long units) +{ + unsigned long long temp; + int ccode; + + print(s); + + temp = num; + temp = (temp * units)/1024; + num = temp; + ccode = print_num(num); + print("\n"); + return ccode; +} + +/* this program has no main(), as startup libraries are not used */ +void _start(void) +{ + int ccode; + struct sysinfo info; + unsigned long used; + + print("Testing system size.\n"); + print("1..1\n"); + + ccode = sysinfo(&info); + if (ccode < 0) { + print("not ok 1 get runtime memory use\n"); + print("# could not get sysinfo\n"); + _exit(ccode); + } + /* ignore cache complexities for now */ + used = info.totalram - info.freeram - info.bufferram; + print_k_value("ok 1 get runtime memory use # size = ", used, + info.mem_unit); + + print("# System runtime memory report (units in Kilobytes):\n"); + print_k_value("# Total: ", info.totalram, info.mem_unit); + print_k_value("# Free: ", info.freeram, info.mem_unit); + print_k_value("# Buffer: ", info.bufferram, info.mem_unit); + print_k_value("# In use: ", used, info.mem_unit); + + _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@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/