On 04/24/2014 06:36 PM, Stephane Eranian wrote: > On Thu, Apr 24, 2014 at 12:25 PM, Yan, Zheng <zheng.z....@intel.com> wrote: >> On 04/24/2014 04:14 PM, Ingo Molnar wrote: >>> >>> * Stephane Eranian <eran...@google.com> wrote: >>> >>>>>> Most of the codes without comments are hardware specific codes. >>>>>> The corresponding contents in Intel uncore documents are big >>>>>> tables/lists, nothing tricky/interesting. I really don't know how >>>>>> to comment these code. >>>>> >>>>> Have a look at other PMU drivers, such as >>>>> arch/x86/kernel/cpu/perf_event_intel_rapl.c, which begin with a >>>>> general explanation attached below. >>>> >>>> I think a more useful modularization would be to split that huge >>>> file (perf_event_intel_uncore.c) into smaller files like we do for >>>> the core PMU. There is just too much stuff in this file for my own >>>> taste. Hard to navigate and I spend quite some time looking at it >>>> and modifying it! >>>> >>>> You could follow the model of the core PMU support files. >>>> You'd have a "core" file with the common routines, and then >>>> a file perf processor: >>>> - perf_event_intel_uncore.c >>>> - perf_event_intel_snbep_uncore.c >>>> - perf_event_intel_nhmex_uncore.c >>>> - perf_event_intel_ivt_uncore.c >>>> - ... >>>> >>>> Each processor specific module, would be a kernel module. The core >>>> could be one too. Note that this would not alleviate the need for >>>> some basic descriptions at the beginning of each file outlining the >>>> PMU boxes exported to a minimum. >> >> Most of hardware specific codes in the Intel uncore driver are for >> SandyBridge/IvyBridge/Haswell. Uncore subsystem in these CPUs are similar. >> One module per CPU type means we have to duplicate lots of code. I don't >> think it's a good idea. >> > Then, at least split nhm_ex from the rest. It is very big.
Ok, will do. Regards Yan, Zheng >> >>> >>> This structure you outline sounds like a good first step, I like it. >>> >>> To simplify this restructuring, initially we could even keep the core >>> uncore bits in the core (ha!), to not have module-on-module >>> dependencies. >>> >>> Thanks, >>> >>> Ingo >>> >> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
