Using GCov in the FreeBSD kernel

[Venkatraman T]

Hi, I am trying to understand what how much effort it would take to get the code coverage in FreeBSD kernel using gcov.

My understanding is we have gcov in FreeBSD which gets code coverage on user space programs. The reasons that this can't be used in kernel right now is because:
1) gcov libs cannot use the standard C libs when the kernel code is compiled with the gcov flags
2) There might be some issues with the kernel's access to the file systems for dumping the .gcda files
What are the other issues that I need to look at?

There is also a kernel patch for Linux (LTP) that allows gcov to get coverage in the kernel. Will it easier to patch FreeBSD gcov libraries to run on the kernel or should I try and modify the Linux kernel patch to work on FreeBSD kernel. I am very new to anything in the kernel and would appreciate any insight on how to go about doing this.

Thanks
Venkat