Re: [PATCH v2 7/9] perf pmu: Merge PMU instances that match the same comma-separated json Unit

[sashiko-bot@kernel.org]

> Since commit 730670b1d108 ("perf pmu: Support more complex PMU event
> aliasing") a json event "Unit" with comma-separated parts matches PMU
> names with an optional number after each part. For example, the NVIDIA
> Tegra410 PCIe PMUs are named nvidia_pcie_pmu_<socket>_rc_<rc>, and the
> Unit "nvidia_pcie_pmu_,rc_" of their json events matches all of them.
> perf uses this match to attach json events and metrics to these PMUs.
> But perf uses a different match to decide which PMUs to combine in the
> counting result, and it only ignores the number at the end of the name.
> So the RCs of the same socket are combined, but the two sockets are not:
> nvidia_pcie_pmu_0_rc_<rc> and nvidia_pcie_pmu_1_rc_<rc> give two
> results.
> 
> On a dual-socket system, this gives one line per socket under the same
> name in the default output, and with --metric-only a metric column per
> socket, a "none" value for the other socket and a duplicate metric key:
> [ ... ]
>   $ perf stat -a --per-socket -j --metric-only -M pcie_avg_wr_bandwidth_to_all_dst -- sleep 1
>   {"socket" : "S268435456", "counters" : 6, "MB/s  pcie_avg_wr_bandwidth_to_all_dst" : "0.0"}
>   {"socket" : "S285212672", "counters" : 6, "MB/s  pcie_avg_wr_bandwidth_to_all_dst" : "0.0"}
> 
> Signed-off-by: Besar Wicaksono <bwicaksono@nvidia.com>

Sashiko has reviewed this patch and found no issues.

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