'Enable event tracing upon kernel module load
I want to use Ftrace event tracer for my kernel module.
It is important to me that I'll be able to trace right when the module loads- in similar fashion to enabling events during boot via the kernel command line.
I had no success with it, I did saw that some effort was made to make this possible (tracing: Enable tracepoints via module parameters).
Can someone point me out if (and if so, how) is this possible?
Solution 1:[1]
Make sure that you have enabled ftrace, debugfs in the kernel config, and those related modules.
After you mount the debugfs, there should be a directory called tracing under the debugfs. Ex /sys/kernel/debug/tracing
You can cat available_tracers to see what are the available tracers
and cat available_filter_functions to see what are the filter functions
You can set something like, ex: echo kfree_skb > set_ftrace_filter to enable the filter.
What did you try and failed at which point?
The official document got more details, https://www.kernel.org/doc/Documentation/trace/ftrace.txt
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Justin Yu |