cr0cd_fbsd

CR0.CD manipulate FreeBSD Kernel Module as a character device.
This is a FreeBSD version of cr0cd

Installation

$ git clone https://github.com/alphaKAI/cr0cd_fbsd
$ cd cr0cd_fbsd
$ make
$ gcc -o reader reader.c

Usage

CR0 exists on each of CPU core, you need specify which core will be disabled by taskset.

$ sudo kldload -v ./cr0cd.ko
$ taskset -c $CORE_NUMBER echo 1 > /dev/cr0cd # Disable CPU Cache
$ taskset -c $CORE_NUMBER some command # run on CPU Cache is disabled
$ taskset -c $CORE_NUMBER echo 0 > /dev/cr0cd # Enable CPU Cache
$ taskset -c $CORE_NUMBER ./reader # display current CR0 bits

Screenshot

This is an example of how CPU Cache disable affects.

Memory access speed down to 3GB/sec -> unmeasurable(too slow).

LICENSE

cr0cd is released under the MIT License.
Please see LICENSE for more details.
Copyright (C) 2019 Akihiro Shoji.