Re: [RFC PATCH v2 2/2] kbuild: call check-atomics.sh only if prerequisites change

From: Masahiro Yamada <masahiroy@kernel.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Mailhol <mailhol.vincent@wanadoo.fr>,
	Michal Marek <michal.lkml@markovi.net>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Andy Shevchenko <andy.shevchenko@gmail.com>,
	Rikard Falkeborn <rikard.falkeborn@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>, Will Deacon <will@kernel.org>
Subject: Re: [RFC PATCH v2 2/2] kbuild: call check-atomics.sh only if prerequisites change
Date: Sun, 15 May 2022 01:26:23 +0900	[thread overview]
Message-ID: <CAK7LNAR+F5PspM+6CP+H+443nJYy+Rg3jmKp1NyJeepq9sSFQA@mail.gmail.com> (raw)
In-Reply-To: <20220514145551.GC100765@worktop.programming.kicks-ass.net>

On Sat, May 14, 2022 at 11:56 PM Peter Zijlstra <peterz@infradead.org> wrote:
>
> On Sat, May 14, 2022 at 03:14:48PM +0200, Peter Zijlstra wrote:
> > On Sat, May 14, 2022 at 04:01:18AM +0900, Masahiro Yamada wrote:
> > > I wrote a different patch.
> > > https://lore.kernel.org/lkml/20220513185340.239753-1-masahiroy@kernel.org/T/#u
> >
> > I'm not seeing that in my inbox :-(
> >
> > AFAICT this way 'make tags' will not find and index the files, which is
> > a total no-go.
> >
> > NAK
>
> Additionally, if you spuriously regenerate these files, you'll risk
> rebuilding huge parts of the kernel through the dependencies.

This is just one-time copying.
Rebuild only happens just once.

BTW, gen-atomics.sh takes more than 1 sec.
Do you think gen-atomics.sh can be much faster
if it is rewritten by Python or Perl?
Then, we can drop 5000 lines from the git repository.

-- 
Best Regards
Masahiro Yamada