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Subject: Re: [PATCH v4 3/4] perf/core: Remove pmu linear searching code
To:     Ian Rogers <irogers@google.com>
Cc:     Marc Zyngier <maz@kernel.org>,
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From:   Thomas Richter <tmricht@linux.ibm.com>
Organization: IBM
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On 5/30/23 16:00, Ian Rogers wrote:
> ls /sys/devices/*/cpu*

Hi Ian,

here is the output yo requested:

# ls /sys/devices/*/cpu*
cpu0  cpu3  cpu6         hotplug     modalias  possible  smt
cpu1  cpu4  cpu7         isolated    offline   present   uevent
cpu2  cpu5  dispatching  kernel_max  online    rescan    vulnerabilities
#

In fact it is the same as 
# ls  /sys/devices/system/cpu/
cpu0  cpu3  cpu6         hotplug     modalias  possible  smt
cpu1  cpu4  cpu7         isolated    offline   present   uevent
cpu2  cpu5  dispatching  kernel_max  online    rescan    vulnerabilities
# 
This directory tree has nothing to do with events for perf, it is
merely used to support CPU hotplug on s390.

The PMUs on s390 are
# ls -ld /sys/devices/{cpum_,pai_}*
drwxr-xr-x 4 root root 0 May 25 15:45 /sys/devices/cpum_cf
drwxr-xr-x 4 root root 0 May 25 15:45 /sys/devices/cpum_cf_diag
drwxr-xr-x 4 root root 0 May 25 15:45 /sys/devices/cpum_sf
drwxr-xr-x 4 root root 0 May 25 15:45 /sys/devices/pai_crypto
drwxr-xr-x 4 root root 0 May 25 15:45 /sys/devices/pai_ext
# 

I hope his helps.

-- 
Thomas Richter, Dept 3303, IBM s390 Linux Development, Boeblingen, Germany
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