The put_user function moves the value that the kernelvariable (var) specifies into the user-space address (PTR). The functions return zero on success.
put_user函数则将内核变量(var)指定的值移动到用户空间地址(ptr)。
2
You examined some important kernel parameters, what they do, and how to tune them, including how to make the best use of the variable page size support.
研究了一些重要的内核参数、它们的作用以及如何对它们进行调优，包括如何最适当地使用可变页面大小支持。
3
Once you have installed this package, make sure that /opt/cross/bin is part of your $PATH environment variable so the tools in the package will be accessible during the kernel build process.