linux-kernel - Re: [PATCH 1/3] perf header: Add die information in CPU topology

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Message-ID: <20190528090014.GF27906@krava>
Date:   Tue, 28 May 2019 11:00:14 +0200
From:   Jiri Olsa <jolsa@...hat.com>
To:     kan.liang@...ux.intel.com
Cc:     acme@...nel.org, jolsa@...nel.org, mingo@...hat.com,
        linux-kernel@...r.kernel.org, peterz@...radead.org,
        ak@...ux.intel.com
Subject: Re: [PATCH 1/3] perf header: Add die information in CPU topology

On Thu, May 23, 2019 at 01:41:19PM -0700, kan.liang@...ux.intel.com wrote:
> From: Kan Liang <kan.liang@...ux.intel.com>
> 
> With the new CPUID.1F, a new level type of CPU topology, 'die', is
> introduced. The 'die' information in CPU topology should be added in
> perf header.
> 
> To be compatible with old perf.data, the patch checks the section size
> before reading the die information. The new info is added at the end of
> the cpu_topology section, the old perf tool ignores the extra data.
> It never reads data crossing the section boundary.
> 
> The new perf tool with the patch can be used on legacy kernel. Add a
> new function check_x86_die_exists() to check if die topology
> information is supported by kernel. The function only check X86 and
> CPU 0. Assuming other CPUs have same topology.

[jolsa@...l-r440-01 perf]$ sudo ./perf stat -e cycles --per-die -a -I 1000
#           time die cpus             counts unit events
     1.000526089 S0-D0          20          6,828,029      cycles
     1.000526089 S1-D0          20          2,609,924      cycles
     2.002578005 S0-D0          20          5,280,361      cycles


the title is shifted from the values

jirka