Re: [PATCH v3 0/9] perf/mem: AMD IBS and generic tools improvements

From: Ravi Bangoria
Date: Sun Apr 09 2023 - 22:24:21 EST


On 08-Apr-23 3:14 AM, Namhyung Kim wrote:
> Hi Ravi,
>
> On Fri, Apr 7, 2023 at 4:25 AM Ravi Bangoria <ravi.bangoria@xxxxxxx> wrote:
>>
>> Kernel IBS driver wasn't using new PERF_MEM_* APIs due to some of its
>> limitations. Mainly:
>>
>> 1. mem_lvl_num doesn't allow setting multiple sources whereas old API
>> allows it. Setting multiple data sources is useful because IBS on
>> pre-zen4 uarch doesn't provide fine granular DataSrc details (there
>> is only one such DataSrc(2h) though).
>> 2. perf mem sorting logic (sort__lvl_cmp()) ignores mem_lvl_num. perf
>> c2c (c2c_decode_stats()) does not use mem_lvl_num at all. perf mem
>> prints mem_lvl and mem_lvl_num both if both are set, which is ugly.
>>
>> Set mem_lvl_num, mem_remote and mem_hops for data_src via IBS. Handle
>> first issue using mem_lvl_num = ANY_CACHE | HOPS_0. In addition to
>> setting new API fields, convert all individual field assignments to
>> compile time wrapper macros built using PERF_MEM_S(). Also convert
>> DataSrc conditional code to array lookups.
>>
>> Interpretation of perf_mem_data_src by perf_mem__lvl_scnprintf() was
>> non-intuitive. Make it sane.
>
> Looks good, but I think you need to split kernel and user patches.

Patch #1 to #3 are kernel changes. Patch #4 to #9 are userspace changes.
Arnaldo, Peter, please let me know if you wants to split the series and
resend.

>
>>
>> v2: https://lore.kernel.org/r/20230327130851.1565-1-ravi.bangoria%40amd.com
>> v2->v3:
>> - IBS: Don't club RmtNode with DataSrc=7 (IO)
>> - Make perf_mem__lvl_scnprintf() more sane
>> - Introduce PERF_MEM_LVLNUM_UNC, set it along with PERF_MEM_LVL_UNC
>> and interpreat it in tool.
>> - Add PERF_MEM_LVLNUM_NA to default data_src value
>> - Change some of the IBS bit description according to latest PPR
>>
>> Namhyung Kim (1):
>> perf/x86/ibs: Set mem_lvl_num, mem_remote and mem_hops for data_src
>>
>> Ravi Bangoria (8):
>> perf/mem: Introduce PERF_MEM_LVLNUM_UNC
>> perf/mem: Add PERF_MEM_LVLNUM_NA to PERF_MEM_NA
>> perf headers: Sync uapi/linux/perf_event.h
>> perf mem: Add PERF_MEM_LVLNUM_NA to PERF_MEM_DATA_SRC_NONE
>> perf mem: Add support for printing PERF_MEM_LVLNUM_UNC
>> perf mem: Refactor perf_mem__lvl_scnprintf()
>> perf mem: Increase HISTC_MEM_LVL column size to 39 chars
>> perf script ibs: Change bit description according to latest PPR
>
> Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Thanks!