From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1753182AbdFUQrM (ORCPT <rfc822;w@1wt.eu>);
        Wed, 21 Jun 2017 12:47:12 -0400
Received: from mga05.intel.com ([192.55.52.43]:13109 "EHLO mga05.intel.com"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1751007AbdFUQrK (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 21 Jun 2017 12:47:10 -0400
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.39,369,1493708400"; 
   d="scan'208";a="983589184"
Subject: Re: [PATCH V3 20/37] perf script: Add 'synth' event type for
 synthesized events
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>, Peter Zijlstra <peterz@infradead.org>,
        Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
        Wang Nan <wangnan0@huawei.com>, David Ahern <dsahern@gmail.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
References: <1495786658-18063-21-git-send-email-adrian.hunter@intel.com>
 <1498040239-32418-1-git-send-email-adrian.hunter@intel.com>
 <20170621135145.GO13640@kernel.org>
From: Adrian Hunter <adrian.hunter@intel.com>
Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki,
 Business Identity Code: 0357606 - 4, Domiciled in Helsinki
Message-ID: <66cdc4e6-58a4-e365-8a76-112daf71baf9@intel.com>
Date: Wed, 21 Jun 2017 19:41:04 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.1.1
MIME-Version: 1.0
In-Reply-To: <20170621135145.GO13640@kernel.org>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On 06/21/2017 04:51 PM, Arnaldo Carvalho de Melo wrote:
> Em Wed, Jun 21, 2017 at 01:17:19PM +0300, Adrian Hunter escreveu:
>> +++ b/tools/perf/util/event.h
>> @@ -252,6 +252,9 @@ enum auxtrace_error_type {
>>        PERF_AUXTRACE_ERROR_MAX
>> };
> 
>> +/* Attribute type for custom synthesized events */
>> +#define PERF_TYPE_SYNTH		3000000000
> 
> Why don't you make it PERF_TYPE_MAX and bump PERF_TYPE_MAX by one? I.e.
> this way we have what can be in attr.type in a nice enumeration, can
> validate it more easily (attr.type < PERF_TYPE_MAX) and will not need to 
> do those conversions to/from OUTPUT_TYPE_/PERF_TYPE_).

PERF_TYPE_ is dynamically allocated above PERF_TYPE_MAX for PMUs.  Presently
perf_pmu_register() calls idr_alloc() with end=0 which limits the allocation
to INT_MAX.

> Peter: now its not the PERF_RECORD_ namespace that userspaces want a
> chunk of, its PERF_TYPE_, which so far has been pretty stable, grabing
> _one_ for event synthesizing things like Intel PT (and ARM's coresight,
> I think) directly at include/uapi/linux/perf_event.h's perf_type_id enum
> looks cleaner, no?