On Thu, Feb 01, 2024 at 05:02:56PM +0100, Daniel Bristot de Oliveira wrote:
On 2/1/24 16:44, Greg KH wrote:
On Thu, Feb 01, 2024 at 04:13:39PM +0100, Daniel Bristot de Oliveira wrote:
Currently, the timerlat's hrtimer is initialized at the first read of timerlat_fd, and destroyed at close(). It works, but it causes an error if the user program open() and close() the file without reading.
What error exactly happens? Userspace, or the kernel crashes?
sorry, kernel crash:
# echo NO_OSNOISE_WORKLOAD > /sys/kernel/debug/tracing/osnoise/options # echo timerlat > /sys/kernel/debug/tracing/current_tracer
# cat ./timerlat_load.py #!/usr/bin/env python3
timerlat_fd = open("/sys/kernel/tracing/osnoise/per_cpu/cpu0/timerlat_fd", 'r') timerlat_fd.close();
# ./taskset -c 0 ./timerlat_load.py
<BOOM>
Then obviously, this is a real, functional, change, so say so in the kernel changelog :)
thanks,
greg k-h