Re: Fix "perf tools: Synthesize GROUP_DESC feature in pipe mode" in the LT 4.14 branch

[Jinpu Wang]

+cc Greg, stable

Greensky, James J <james.j.greensky@xxxxxxxxx> ä2018å12æ21æåä äå11:48åéï
>
> Commit d38d272592737ea88a20 ("perf tools: Synthesize GROUP_DESC feature in pipe mode") broke the LT 4.14 branch when using event groups in pipe-mode.
>
>   # perf record -e '{cycles,instructions,branches}' -- sleep 4 | perf report
>   # To display the perf.data header info, please use --header/--header-only options
>   #
>   Oxd7c [0x60]: failed to process type: 80
>   Error:
>   Failed to process sample
>
> Commit a2015516c5c0be932a69 ("perf record: Synthesize features before events in pipe mode") is the fix. Can we get this cherry-picked and applied?
>