Re: [PATCH v9 00/16] New perf ilist app

[Namhyung Kim <namhyung@kernel.org>]

On Sat, Jul 26, 2025 at 04:12:29PM -0700, Namhyung Kim wrote:
> Hi Ian,
> 
> On Fri, Jul 25, 2025 at 11:51:46AM -0700, Ian Rogers wrote:
> > This patch series builds up to the addition of a new ilist app written
> > in python using textual [1] for the UI. The app presents perf PMUs and
> > events, displays the event information as in `perf list` while at the
> > bottom of the console showing recent activity of the event in total
> > and across all CPUs. It also displays metrics, placed in a tree
> > through their metric group, again with counts being displayed in the
> > bottom panel.
> > 
> > The first ground work patches of fixes, cleanup and refactoring were
> > separated into their own series here:
> > https://lore.kernel.org/lkml/20250709214029.1769089-1-irogers@google.com/
> > 
> > The second part of the patches adds event json for the software PMU
> > and makes the tracepoint PMU support iteration of events and the
> > like. Without these improvements the tracepoint and software PMUs will
> > appear to have no events in the ilist app. As the software PMU moves
> > parsing to json, the legacy hard coded parsing is removed. This has
> > proven controversial for hardware events and so that cleanup isn't
> > done here.
> 
> Even software PMU can be controversial. :)  But I think we can try this
> first.  Basically this will change the output `perf list` and the event
> parsing behavior.
> 
> For example, `perf list sw` will look like:
> 
> software:
>   alignment-faults
>        [Number of kernel handled memory alignment faults. Unit: software]
>   bpf-output
>        [An event used by BPF programs to write to the perf ring buffer. Unit: software]
>   cgroup-switches
>        [Number of context switches to a task in a different cgroup. Unit: software]
>   context-switches
>        [Number of context switches [This event is an alias of cs]. Unit: software]
>   cpu-clock
>        [Per-CPU high-resolution timer based event. Unit: software]
>   cpu-migrations
>        [Number of times a process has migrated to a new CPU [This event is an alias of migrations]. Unit: software]
>   cs
>        [Number of context switches [This event is an alias of context-switches]. Unit: software]
>   dummy
>        [A placeholder event that doesn't count anything. Unit: software]
>   ...
> 
> Let's add this change and see if people complain..
> 
> Btw, I think the alias can be one-way.  IOW 'context-switches' is a
> software event and 'cs' is an alias to it, not vice versa.  I'll make
> the change.

Hmm.. this needs to rebuild the string index and causes a build error.
I'll just leave it as is and we can update it later.

Thanks,
Namhyung