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;
IronPort-SDR: WDrkQNQ2wXYPdbJ1VTWNmY+Pmc2zIORyEr9Xg/pLexEHXX127tR+YXmwvSm8Z5uC9d8PrfBeJf
 joQV+VHg4MOg==
IronPort-SDR: +H+uyDnAdfr8cJDrP055+A8lC6iSk1E+zH3WH4J/KfBmnxC9E6j7NkSanmzaGV1Ka3l1ePegPW
 qTH2sYsquYew==
Subject: Re: [PATCH v5 13/13] perf record: introduce --ctl-fd[-ack] options
To:     Alexey Budankov <alexey.budankov@linux.intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Andi Kleen <ak@linux.intel.com>,
        linux-kernel <linux-kernel@vger.kernel.org>
References: <e5cac8dd-7aa4-ec7c-671c-07756907acba@linux.intel.com>
 <8ffc9f9f-af58-deea-428b-f8a69004e3cb@linux.intel.com>
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: <923c40c7-7c0b-9fad-314d-69e7acbee201@intel.com>
Date:   Mon, 1 Jun 2020 19:30:58 +0300
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101
 Thunderbird/68.7.0
MIME-Version: 1.0
In-Reply-To: <8ffc9f9f-af58-deea-428b-f8a69004e3cb@linux.intel.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 1/06/20 7:05 pm, Alexey Budankov wrote:
> 
> Introduce --ctl-fd[-ack] options to pass open file descriptors numbers
> from command line. Extend perf-record.txt file with --ctl-fd[-ack]
> options description. Document possible usage model introduced by
> --ctl-fd[-ack] options by providing example bash shell script.

Hi

I am interested in using this also for taking snapshots.

Did you consider using a single option, or allowing either a file descriptor
or a pathname, or including also the event default of "disabled".

e.g. add "--control" and support all of:

--control
--control 11
--control 11,15
--control 11,15,disabled
--control 11,,disabled
--control /tmp/my-perf.fifo
--control /tmp/my-perf.fifo,/tmp/my-perf-ack.fifo
--control /tmp/my-perf.fifo,/tmp/my-perf-ack.fifo,disabled
--control /tmp/my-perf.fifo,,disabled

Regards
Adrian