在 Linux 中，SD 卡、eMMC 设备都使用 mmc 总线，所以可以采用统一的测试方法。
这里的思路是，先生成一个 1MB 大小的文件，写入设备，然后读取出来存到另一个文件。再使用 cmp 命令对比两个文件的内容是否一致。存储设备可能存在多个分区，所以对每一个分区都进行一次以上测试。
mmc_test.sh：
#!/bin/bash
# Description:
# Test SD or eMMC device with mount point. Get mount point from /proc/mounts.if [ $# -ne 1 ]
thenecho "Usage $0 <mmc device>"echo "e.g. $0 mmcblk0"exit 2
fiMMC_DEVICE=$1
WRITE_TEST_FILE=/tmp/solid_disk_test.write
READ_TEST_FILE=/tmp/solid_disk_test.read# get all mount points
MOUNT_POINTS=(`cat /proc/mounts | grep media | grep ${MMC_DEVICE} | awk '{print $2}'`)dd if=/dev/zero of=${WRITE_TEST_FILE} bs=1024k count=1 > /dev/null 2>&1for i in ${MOUNT_POINTS[@]}
do# Write, read and compare.dd if=${WRITE_TEST_FILE} of=$i/RW_TEST bs=1024k count=1 > /dev/null 2>&1dd if=$i/RW_TEST of=${READ_TEST_FILE} > /dev/null 2>&1cmp ${WRITE_TEST_FILE} ${READ_TEST_FILE}if [ $? -eq 0 ]thenecho "Test pass!"exit 0fi
doneecho "Can not find $1, test failed!"
exit 3考虑到全新生产的板卡上 eMMC 可能还没分区，也就没有挂载，故对上面测试程序进行了改进。先检测是否存在 p1 分区。同时把全零的测试数据改为了使用随机数。
emmc_test.sh：
#!/bin/bash
# Description:
# Test eMMC device.MMC_DEVICE=/dev/mmcblk1
WRITE_TEST_FILE=/tmp/solid_disk_test.write
READ_TEST_FILE=/tmp/solid_disk_test.read# generate file to write.
dd if=/dev/urandom of=${WRITE_TEST_FILE} bs=1024k count=1 > /dev/null 2>&1if [[ ! -e ${MMC_DEVICE}p1 ]];then # there is no partition in emmc yet.dd if=${WRITE_TEST_FILE} of=${MMC_DEVICE} bs=1024k count=1 > /dev/null 2>&1dd if=${MMC_DEVICE} of=${READ_TEST_FILE} bs=1024k count=1 > /dev/null 2>&1cmp ${WRITE_TEST_FILE} ${READ_TEST_FILE}if [ $? -eq 0 ];thenecho "Test pass!"exit 0elseecho "Test failed!"exit 3fi
else# get all mount pointsMOUNT_POINTS=(`cat /proc/mounts | grep media | grep ${MMC_DEVICE} | awk '{print $2}'`)for i in ${MOUNT_POINTS[@]}do# Write, read and compare.dd if=${WRITE_TEST_FILE} of=$i/RW_TEST bs=1024k count=1 > /dev/null 2>&1dd if=$i/RW_TEST of=${READ_TEST_FILE} > /dev/null 2>&1cmp ${WRITE_TEST_FILE} ${READ_TEST_FILE}if [ $? -ne 0 ];thenecho "Test failed!"exit 3fidoneecho "Test pass!"exit 0
fi参考
《存储设备与总线性能测试工具 Fio》：https://blog.csdn.net/engrossment/article/details/100033300
2020年10月20日