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Date:   Fri, 4 Oct 2019 13:22:37 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Daniel Bristot de Oliveira <bristot@redhat.com>,
        linux-kernel@vger.kernel.org, x86@kernel.org,
        Nadav Amit <nadav.amit@gmail.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Song Liu <songliubraving@fb.com>,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH 3/3] x86/ftrace: Use text_poke()
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On Thu, Oct 03, 2019 at 06:10:45PM -0400, Steven Rostedt wrote:
> But still, we are going from 120 to 660 IPIs for every CPU. Not saying
> it's a problem, but something that we should note. Someone (those that
> don't like kernel interference) may complain.

It is machine wide function tracing, interference is going to happen..
:-)

Anyway, we can grow the batch size if sufficient benefit can be shown to
exist.