编写Linux驱动测试用例是确保驱动稳定性和功能正确性的关键步骤。以下是编写Linux驱动测试用例的详细方法和最佳实践。
在开始编写测试用例前,需要搭建合适的测试环境:
# 安装必要的开发工具
sudo apt-get install build-essential linux-headers-$(uname -r)
Linux驱动测试常用的框架:
#include <kunit/test.h>
static void example_test(struct kunit *test)
{
int result = some_driver_function();
KUNIT_EXPECT_EQ(test, result, 0);
}
static struct kunit_case example_test_cases[] = {
KUNIT_CASE(example_test),
{}
};
static struct kunit_suite example_test_suite = {
.name = "example_driver_test",
.test_cases = example_test_cases,
};
kunit_test_suite(example_test_suite);
#include "../kselftest.h"
static int example_test(void)
{
int ret;
ret = test_driver_feature();
if (ret != 0) {
ksft_print_msg("Test failed: %d\n", ret);
return KSFT_FAIL;
}
return KSFT_PASS;
}
int main(int argc, char **argv)
{
ksft_print_header();
ksft_set_plan(1);
ksft_test_result(example_test() == KSFT_PASS, "Driver feature test");
ksft_finished();
return 0;
}
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#define DEVICE_PATH "/dev/example"
int main()
{
int fd = open(DEVICE_PATH, O_RDWR);
if (fd < 0) {
perror("Failed to open device");
return -1;
}
// 测试写入
char buf[32] = "test data";
if (write(fd, buf, sizeof(buf)) != sizeof(buf)) {
perror("Write failed");
close(fd);
return -1;
}
// 测试读取
if (read(fd, buf, sizeof(buf)) != sizeof(buf)) {
perror("Read failed");
close(fd);
return -1;
}
close(fd);
return 0;
}
#include <time.h>
void test_performance()
{
struct timespec start, end;
clock_gettime(CLOCK_MONOTONIC, &start);
// 执行测试操作
perform_driver_operation();
clock_gettime(CLOCK_MONOTONIC, &end);
double elapsed = (end.tv_sec - start.tv_sec) +
(end.tv_nsec - start.tv_nsec) / 1e9;
printf("Operation took %.6f seconds\n", elapsed);
}
#include <pthread.h>
#define THREAD_COUNT 10
void *test_thread(void *arg)
{
// 并发访问驱动
int fd = open(DEVICE_PATH, O_RDWR);
// ... 执行操作
close(fd);
return NULL;
}
void test_concurrency()
{
pthread_t threads[THREAD_COUNT];
for (int i = 0; i < THREAD_COUNT; i++) {
pthread_create(&threads[i], NULL, test_thread, NULL);
}
for (int i = 0; i < THREAD_COUNT; i++) {
pthread_join(threads[i], NULL);
}
}
obj-m := example_driver.o
test-objs := example_test.o
all:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
gcc -o driver_test driver_test.c
test:
insmod example_driver.ko
./driver_test
rmmod example_driver.ko
clean:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean
rm -f driver_test
可以在CI系统中添加测试步骤,例如在GitLab CI中:
test_driver:
stage: test
script:
- make
- make test
only:
- merge_requests
使用gcov和lcov分析测试覆盖率:
# 在Makefile中添加调试标志
EXTRA_CFLAGS += -fprofile-arcs -ftest-coverage
# 生成覆盖率报告
lcov --capture --directory . --output-file coverage.info
genhtml coverage.info --output-directory coverage_report
通过以上方法,您可以构建全面的Linux驱动测试套件,确保驱动的稳定性和可靠性。