Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Message-ID: <5e2262a3-ec27-fa3e-c5d1-3a5e25a42042@linux.intel.com>
Date:   Wed, 13 Oct 2021 17:37:47 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101
 Thunderbird/91.2.0
Subject: Re: [PATCH] perf/x86/intel: fix ICL/SPR INST_RETIRED.PREC_DIST
 encodings
Content-Language: en-US
To:     Stephane Eranian <eranian@google.com>, linux-kernel@vger.kernel.org
Cc:     peterz@infradead.org, kan.liang@intel.com
References: <20211014001214.2680534-1-eranian@google.com>
From:   Andi Kleen <ak@linux.intel.com>
In-Reply-To: <20211014001214.2680534-1-eranian@google.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 10/13/2021 5:12 PM, Stephane Eranian wrote:
> This patch fixes the encoding for INST_RETIRED.PREC_DIST as published by Intel
> (download.01.org/perfmon/) for Icelake. The official encoding
> is event code 0x00 umask 0x1, a change from Skylake where it was code 0xc0
> umask 0x1.
>
> With this patch applied it is possible to run:
> $ perf record -a -e cpu/event=0x00,umask=0x1/pp .....
>
> Whereas before this would fail.
>
> To avoid problems with tools which may use the old code, we maintain the old
> encoding for Icelake.
>
> Signed-off-by: Stephane Eranian <eranian@google.com>


Make sense.

Reviewed-by: Andi Kleen <ak@linux.intel.com>


-Andi