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Date:   Thu, 18 Aug 2022 14:49:20 +0100
Message-ID: <87mtc1wtjz.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Dmitry Rokosov <DDRokosov@sberdevices.ru>
Cc:     "broonie@kernel.org" <broonie@kernel.org>,
        "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
        "rafael@kernel.org" <rafael@kernel.org>,
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        "linux@rasmusvillemoes.dk>" <linux@rasmusvillemoes.dk>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
        "andy.shevchenko@gmail.com" <andy.shevchenko@gmail.com>,
        kernel <kernel@sberdevices.ru>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1] regmap: introduce value tracing for regmap bulk operations
In-Reply-To: <20220818121515.6azkxyqetnunwsc6@CAB-WSD-L081021.sigma.sbrf.ru>
References: <20220816181451.5628-1-ddrokosov@sberdevices.ru>
        <20220818121515.6azkxyqetnunwsc6@CAB-WSD-L081021.sigma.sbrf.ru>
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On Thu, 18 Aug 2022 13:15:00 +0100,
Dmitry Rokosov <DDRokosov@sberdevices.ru> wrote:
> 
> +Thomas, Rasmus and Marc
> 
> On Tue, Aug 16, 2022 at 06:14:48PM +0000, Dmitry Rokosov wrote:
> > Currently, only one-register io operations support tracepoints with
> > value logging. For the regmap bulk operations developer can view
> > hw_start/hw_done tracepoints with starting reg number and registers
> > count to be reading or writing. This patch injects tracepoints with
> > dumping registers values in the hex format to regmap bulk reading
> > and writing.

I don't care much about regmap as a MMIO backend, but it strikes me as
odd that you end up with multiple ways of logging the same stuff (with
a memcpy in the middle of it).

Why can't this be done with a small amount of trace post-processing?

	M.

-- 
Without deviation from the norm, progress is not possible.