Re: [RFC v3][PATCH 0/2] Make ftrace able to trace function return

From: Frédéric Weisbecker
Date: Tue Nov 11 2008 - 14:15:01 EST


2008/11/11 Ingo Molnar <mingo@xxxxxxx>:
>
> * Frédéric Weisbecker <fweisbec@xxxxxxxxx> wrote:
>
>> > at the risk of bikeshed-painting this issue too much, the problem
>> > with function_return is that it has little meaning to actual users
>> > and even to developers. What does the "return" mean? We know what
>> > it means, because we know that opposed to function entry we'll
>> > also capture function returns, and hence be able to do full
>> > function call tracing.
>> >
>> > so function_full i thought to conduct this aspect of it better.
>> > But suggestions are welcome.
>>
>>
>> Ok. Let's change into function_full, after all, I think that this
>> tool will be mostly used with a parsing pass of its traces with a
>> script to produce statistics and hierarchical representation like
>> does draw_functrace.py After that, the order of apparition of the
>> functions in the trace will not really matter.
>
> how about function_cost ?
>
> that's what it's primarily about at this stage: the ability to capture
> entry+exit, and have the cost printed.
>
> as opposed to function tracer, which traces function entry events, but
> does not try to build a coherent picture about per function execution
> cost.
>
> Ingo
>

Ah yes. That's better!
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