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From: Namhyung Kim <namhyung@kernel.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, Namhyung Kim <namhyung.kim@lge.com>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
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        "zhangwei\(Jovi\)" <jovi.zhangwei@huawei.com>,
        Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Subject: Re: [PATCH 10/13] tracing/uprobes: Fetch args before reserving a ring buffer
References: <1383029621-7384-1-git-send-email-namhyung@kernel.org>
	<1383029621-7384-11-git-send-email-namhyung@kernel.org>
	<20131101150910.GA18278@redhat.com> <20131101152232.GA2703@redhat.com>
	<20131103202037.GA2785@redhat.com> <87txfs37ta.fsf@sejong.aot.lge.com>
	<20131104143813.GB4440@redhat.com>
Date: Tue, 05 Nov 2013 10:17:42 +0900
In-Reply-To: <20131104143813.GB4440@redhat.com> (Oleg Nesterov's message of
	"Mon, 4 Nov 2013 15:38:13 +0100")
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On Mon, 4 Nov 2013 15:38:13 +0100, Oleg Nesterov wrote:
> On 11/04, Namhyung Kim wrote:
>>
>> On Sun, 3 Nov 2013 21:20:37 +0100, Oleg Nesterov wrote:
>> >
>> > But. Perhaps it makes sense to at least add a couple of trivial
>> > helpers in 10/13? Something like arg_buf_get/put/init, just to
>> > simplify the potential changes.
>>
>> Good idea.  How about something like below?
>
> Thanks, I agree with any implementation ;)
>
>> static DEFINE_MUTEX(uprobe_buffer_mutex);
>
> but see my previous email, afaics we don't need it.

I see.  Probably checking the event_mutex is locked in front of the
_enable/disable function would be enough.

Thanks,
Namhyung