Message-ID: <CAHk-=wjRWi1cUPQ2BrWCi-Tm3Xv3is0SbAktqkYQx5VBF3cNoA@mail.gmail.com>
Date: Tue, 11 Jun 2024 16:48:51 -0700
From: Linus Torvalds <torvalds@...ux-foundation.org>
To: Yury Norov <yury.norov@...il.com>
Cc: Linus Walleij <linus.walleij@...aro.org>, linux-kernel@...r.kernel.org, 
	Jani Nikula <jani.nikula@...ux.intel.com>, 
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>, 
	"Rafael J. Wysocki" <rafael.j.wysocki@...el.com>, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Guenter Roeck <linux@...ck-us.net>, 
	Randy Dunlap <rdunlap@...radead.org>, Andi Shyti <andi.shyti@...nel.org>, 
	Lee Jones <lee@...nel.org>, Arseniy Krasnov <AVKrasnov@...rdevices.ru>, 
	Johannes Berg <johannes.berg@...el.com>, Bjorn Helgaas <bhelgaas@...gle.com>, 
	Robert Richter <rrichter@....com>, Vinod Koul <vkoul@...nel.org>, Hans de Goede <hdegoede@...hat.com>, 
	Nikita Kravets <teackot@...il.com>, Jiri Slaby <jirislaby@...nel.org>, 
	Heikki Krogerus <heikki.krogerus@...ux.intel.com>, 
	Kent Overstreet <kent.overstreet@...ux.dev>, Eric Biggers <ebiggers@...gle.com>, 
	Kees Cook <keescook@...omium.org>, Ingo Molnar <mingo@...nel.org>, 
	"Steven Rostedt (Google)" <rostedt@...dmis.org>, Daniel Bristot de Oliveira <bristot@...nel.org>, 
	Andrew Morton <akpm@...ux-foundation.org>, Hugh Dickins <hughd@...gle.com>, 
	John Johansen <john.johansen@...onical.com>, Eric Snowberg <eric.snowberg@...cle.com>, 
	Takashi Iwai <tiwai@...e.de>, Takashi Sakamoto <o-takashi@...amocchi.jp>, Mark Brown <broonie@...nel.org>, 
	Kuninori Morimoto <kuninori.morimoto.gx@...esas.com>, Nicholas Piggin <npiggin@...il.com>, 
	Christophe Leroy <christophe.leroy@...roup.eu>, Thomas Gleixner <tglx@...utronix.de>, 
	Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, 
	Dave Hansen <dave.hansen@...ux.intel.com>, "H. Peter Anvin" <hpa@...or.com>, 
	David Howells <dhowells@...hat.com>, "David S. Miller" <davem@...emloft.net>, 
	"Rafael J. Wysocki" <rafael@...nel.org>, Len Brown <lenb@...nel.org>, Sergey Shtylyov <s.shtylyov@....ru>, 
	Damien Le Moal <dlemoal@...nel.org>, Niklas Cassel <cassel@...nel.org>, Stephen Boyd <sboyd@...nel.org>, 
	Florian Fainelli <florian.fainelli@...adcom.com>, Ray Jui <rjui@...adcom.com>, 
	Peter De Schrijver <pdeschrijver@...dia.com>, Prashant Gaikwad <pgaikwad@...dia.com>, 
	Thierry Reding <thierry.reding@...il.com>, Jonathan Hunter <jonathanh@...dia.com>, 
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, Maxime Ripard <mripard@...nel.org>, 
	Thomas Zimmermann <tzimmermann@...e.de>, David Airlie <airlied@...il.com>, Daniel Vetter <daniel@...ll.ch>, 
	Rodrigo Vivi <rodrigo.vivi@...el.com>, Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>, 
	Tvrtko Ursulin <tursulin@...ulin.net>, Karol Herbst <kherbst@...hat.com>, Lyude Paul <lyude@...hat.com>, 
	Danilo Krummrich <dakr@...hat.com>, Jean Delvare <jdelvare@...e.com>, 
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>, Pavel Machek <pavel@....cz>, 
	Jernej Skrabec <jernej.skrabec@...il.com>, Ulf Hansson <ulf.hansson@...aro.org>, 
	Eric Dumazet <edumazet@...gle.com>, Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
	Miri Korenblit <miriam.rachel.korenblit@...el.com>, Kalle Valo <kvalo@...nel.org>, 
	Kishon Vijay Abraham I <kishon@...nel.org>, Sebastian Reichel <sre@...nel.org>, 
	Daniel Lezcano <daniel.lezcano@...aro.org>, Tejun Heo <tj@...nel.org>, 
	Johannes Weiner <hannes@...xchg.org>, Peter Zijlstra <peterz@...radead.org>, 
	Juri Lelli <juri.lelli@...hat.com>, Vincent Guittot <vincent.guittot@...aro.org>, 
	Dietmar Eggemann <dietmar.eggemann@....com>, Ben Segall <bsegall@...gle.com>, 
	Mel Gorman <mgorman@...e.de>, Daniel Bristot de Oliveira <bristot@...hat.com>, 
	Valentin Schneider <vschneid@...hat.com>, Masami Hiramatsu <mhiramat@...nel.org>, 
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>, Jason Baron <jbaron@...mai.com>, 
	Paul Moore <paul@...l-moore.com>, James Morris <jmorris@...ei.org>, 
	"Serge E. Hallyn" <serge@...lyn.com>, Dmitry Kasatkin <dmitry.kasatkin@...il.com>, 
	Clemens Ladisch <clemens@...isch.de>, Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>
Subject: Re: [PATCH v1 1/1] treewide: Align match_string() with sysfs_match_string()

On Tue, 11 Jun 2024 at 14:38, Yury Norov <yury.norov@...il.com> wrote:
>
> On Mon, Jun 10, 2024 at 10:08:00AM +0200, Linus Walleij wrote:
>
> Hi Linus,

Real Linus here, not that other non-real one.

> I think about renaming set_bit() stuff for atomicity at least twice
> a year.

Yeah, no. The double underscores are historical, and not always great,
but when it comes to the bit ops they are at least fairly obvious: the
double-underscore version is the "unlocked" version.

That is, in fact, the very traditional logic for the in-kernel use:
the traditional model for double underscores is the "this is the
underlying implementation that doesn't do the whole thing, don't use
unless you know *exactly* what you are doing".

So for the bitops, it means "not atomic".

For user accesses, it meant "doesn't do the full checking".

And for a lot of other things, it meant "you need to take the proper lock".

So there's actually often that kind of unifying logic there.

For this match_string() thing, that was *not* the case. There the
double underscore just meant "non-array interface". I NAK'ed it
elsewhere for that - and other - reasons.

             Linus

Powered by blists - more mailing lists