Re: [PATCH v3 0/7] perf: Add ioctl for PMU driver configuration

[Kim Phillips]

On Wed, 18 Jul 2018 15:48:00 -0600
Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> wrote:

> This set adds the capability to communiate event specific configuration
> to the PMU kernel driver using an ioctl().  The functionatlity is made
> generic enough for anyone to use but is targeted at the identification
> of CoreSight sinks when operating in CPU-wide trace scenarios.
> 
> ---
> Changes for V3:
> . Return an error for CPU-wide scenarios while the feature is being
>   implemented (Kim)

Hi, I'm giving this series a short test-drive on Juno.

It yields success for the --per-thread case..:

$ sudo taskset -c 0 ./perf record -e cs_etm/@20010000.etf/ --per-thread uname -a
Linux juno 4.18.0-rc8-00011-gb82af52c4b35-dirty #147 SMP PREEMPT Thu Aug 9 11:20:37 CDT 2018 aarch64 GNU/Linux
[ perf record: Woken up 0 times to write data ]
Warning:
AUX data lost 1 times out of 2!

[ perf record: Captured and wrote 0.067 MB perf.data ]
$ 

..but not for CPU-wide?:

$ sudo taskset -c 0 ./perf record -e cs_etm/@20010000.etf/ uname -a
failed to mmap with 12 (Cannot allocate memory)
$ sudo taskset -c 0 ./perf record -e cs_etm/@20010000.etf/ -C 0 uname -a
failed to mmap with 12 (Cannot allocate memory)
$ 

Thanks,

Kim