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From: Linus Walleij <linus.walleij@linaro.org>
Date: Thu, 2 May 2024 10:23:08 +0200
Message-ID: <CACRpkdb2eJWVYREhpCUoJnYeutBybBY8mic2SAUuU67MW5Hjbg@mail.gmail.com>
Subject: Re: [PATCH v3 4/9] drm/mipi-dsi: Reduce driver bloat of mipi_dsi_*_write_seq()
To: Douglas Anderson <dianders@chromium.org>
Cc: dri-devel@lists.freedesktop.org, Jani Nikula <jani.nikula@linux.intel.com>, 
	Dmitry Baryshkov <dmitry.baryshkov@linaro.org>, 
	Cong Yang <yangcong5@huaqin.corp-partner.google.com>, Hsin-Yi Wang <hsinyi@google.com>, 
	Brian Norris <briannorris@chromium.org>, Sam Ravnborg <sam@ravnborg.org>, 
	Neil Armstrong <neil.armstrong@linaro.org>, Javier Martinez Canillas <javierm@redhat.com>, 
	Joel Selvaraj <jo@jsfamily.in>, lvzhaoxiong@huaqin.corp-partner.google.com, 
	Daniel Vetter <daniel@ffwll.ch>, David Airlie <airlied@gmail.com>, 
	Maarten Lankhorst <maarten.lankhorst@linux.intel.com>, Maxime Ripard <mripard@kernel.org>, 
	Thomas Zimmermann <tzimmermann@suse.de>, linux-kernel@vger.kernel.org
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On Wed, May 1, 2024 at 5:43=E2=80=AFPM Douglas Anderson <dianders@chromium.=
org> wrote:

> Through a cooperative effort between Hsin-Yi Wang and Dmitry
> Baryshkov, we have realized the dev_err() in the
> mipi_dsi_*_write_seq() macros was causing quite a bit of bloat to the
> kernel. Let's hoist this call into drm_mipi_dsi.c by adding a "chatty"
> version of the functions that includes the print. While doing this,
> add a bit more comments to these macros making it clear that they
> print errors and also that they return out of _the caller's_ function.

This doesn't really explain why this takes so much less space.

Please add some explanation like that "the macro gets inlined
and thus the error report string gets inlined into every call to
mipi_dsi_dcs_write_seq() and mipi_dsi_generic_write_seq(),
by using a call to a "chatty" function, the usage is reduced to one
string in the chatty function and a function call at the invoking
site".

With some explanation like that +/- added in:
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij