Re: [PATCH perf-tools-next v4 4/5] perf ftrace: Support omitting execution duration in function graph tracer

[sashiko-bot@kernel.org]

> The Linux kernel's function graph tracer displays the execution duration
> of completed functions by default via the funcgraph-duration trace
> option. Whilst informative, in scenarios where the user is solely
> interested in the call graph topology, call flow sequence, or inlined
> hierarchy, the duration column can add visual clutter and widen each
> trace line.
> 
> Introduce support for omitting function duration by exposing the
> noduration sub-option under --graph-opts. Consistent with the existing
> nosleep-time and noirqs sub-options, it accepts an optional value, so
> noduration=0 explicitly retains the duration column; when specified
> more than once, the last occurrence takes effect. When enabled, perf
> ftrace configures the kernel's tracing instance option
> funcgraph-duration to 0, and restores it to 1 upon resetting tracing
> options.
> 
> Because the profile subcommand fundamentally requires function execution
> duration to compute timing statistics and call counts, combining
> noduration with perf ftrace profile is rejected with an explicit error.
> 
> Signed-off-by: Aaron Tomlin <atomlin@atomlin.com>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20261014161457.373253-1-atomlin@atomlin.com?part=4