"Wu, Fei" <fei2...@intel.com> writes:
> On 4/11/2023 3:27 PM, Alex Bennée wrote: >> >> "Wu, Fei" <fei2...@intel.com> writes: >> >>> On 4/10/2023 6:36 PM, Alex Bennée wrote: >>>> >>>> Richard Henderson <richard.hender...@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.ben...@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 >> >> Yes. >> >>> >>> btw, the archive seems broken and cannot show the whole series: >>> https://www.mail-archive.com/qemu-devel@nongnu.org/msg650258.html >> >> I have a v10 branch here: >> >> https://github.com/stsquad/qemu/tree/tcg/tbstats-and-perf-v10 >> >> I think the top two patches can be dropped on a re-base as the JIT/perf >> integration is already merged. It might be a tricky re-base though. >> Depends on how much churn there has been in the tree since. >> > I'd like to try it. Why has it not been merged upstream? Bits have been merged (the perf jit support) but the original GSoC student moved on and I ran out of time to work on it. It became yet another back burner series that awaits some spare hacking time. > > Thanks, > Fei. > >>> >>> Thanks, >>> Fei. >>> >>>>> >>>>> >>>>> r~ >>>> >>>> >> >> -- Alex Bennée Virtualisation Tech Lead @ Linaro
