Re: perf-trace: improving ioctl details

[Arnaldo Melo]

On February 18, 2026 2:09:26 PM GMT-03:00, David Ahern <dsahern@xxxxxxxxxx> wrote:
>Hi Arnaldo, Namhyung:
>
>I have a couple of patches to perf-trace to improve the details on ioctl
>calls. The first one tracks stats by individual filenames, and for the
>summary output prints the ioctl stats per filename.
>

Looks interesting!


>The second patch improves the output for the _IOC_NR element of the op
>argument. For flexibility across kernel versions and drivers, it adds
>the ability to read input files that contain the conversion from number
>to human readable name. The files (if the option is set) are parsed at
>start up. In addition to the summary, the cache is also used to improve
>the readability of each ioctl line.
>
>Questions for you:
>1. is such an open ended design acceptable for perf-trace?

Is it lazy, i.e. only when needed this cache/table gets loaded? 

>
>2. if yes, is there any preference on file format (json, yaml,
>key-value, ...)?

We already have JSON parsing infra, so probably that is better? 

Great to see you contributing to perf again! 

- Arnaldo

>
>Thanks,
>David

- Arnaldo