Re: [PATCH 1/2] accel/tcg/plugin: export host insn size

[Wu, Fei]

On 4/10/2023 6:36 PM, Alex Bennée wrote:
> 
> Richard Henderson <richard.henderson@linaro.org> writes:
> 
>> On 4/6/23 00:46, Alex Bennée wrote:
>>> If your aim is to examine JIT efficiency what is wrong with the current
>>> "info jit" that you can access via the HMP? Also I'm wondering if its
>>> time to remove the #ifdefs from CONFIG_PROFILER because I doubt the
>>> extra data it collects is that expensive.
>>> Richard, what do you think?
>>
>> What is it that you want from CONFIG_PROFILER that you can't get from perf?
>> I've been tempted to remove CONFIG_PROFILER entirely.
> 
> I think perf is pretty good at getting the hot paths in the translator
> and pretty much all of the timer related stuff in CONFIG_PROFILER could
> be dropped. However some of the additional information about TCG ops
> usage and distribution is useful. That said last time I had a tilt at
> this on the back of a GSoC project:
> 
>   Subject: [PATCH  v9 00/13] TCG code quality tracking and perf integration
>   Date: Mon,  7 Oct 2019 16:28:26 +0100
>   Message-Id: <20191007152839.30804-1-alex.bennee@linaro.org>
> 
> The series ended up moving all the useful bits of CONFIG_PROFILER into
> tb stats which was dynamically controlled on a per TB basis. Now that
> the perf integration stuff was merged maybe there is a simpler series to
> be picked out of the remains?
> 
> Fei Wu,
> 
> Have you looked at the above series? Is that gathering the sort of
> things you need? Is this all in service of examining the translation
> quality of hot code?
> 
Yes, it does have what I want, I suppose this wiki is for the series:
    https://wiki.qemu.org/Features/TCGCodeQuality

btw, the archive seems broken and cannot show the whole series:
    https://www.mail-archive.com/qemu-devel@nongnu.org/msg650258.html

Thanks,
Fei.

>>
>>
>> r~
> 
>