Date:   Tue, 4 Jan 2022 18:05:42 +0200
From:   Andy Shevchenko <andriy.shevchenko@intel.com>
To:     Ingo Molnar <mingo@kernel.org>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "David S. Miller" <davem@davemloft.net>,
        Ard Biesheuvel <ardb@kernel.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Al Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH 0000/2297] [ANNOUNCE, RFC] "Fast Kernel Headers" Tree
 -v1: Eliminate the Linux kernel's "Dependency Hell"
Message-ID: <YdRwVgv+GyUw5iKW@smile.fi.intel.com>
References: <YdIfz+LMewetSaEB@gmail.com>
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On Sun, Jan 02, 2022 at 10:57:35PM +0100, Ingo Molnar wrote:
> 
> I'm pleased to announce the first public version of my new "Fast Kernel 
> Headers" project that I've been working on since late 2020, which is a 
> comprehensive rework of the Linux kernel's header hierarchy & header 
> dependencies, with the dual goals of:
> 
>  - speeding up the kernel build (both absolute and incremental build times)
> 
>  - decoupling subsystem type & API definitions from each other
> 
> The fast-headers tree consists of over 25 sub-trees internally, spanning 
> over 2,200 commits, which can be found here:
> 
>    git://git.kernel.org/pub/scm/linux/kernel/git/mingo/tip.git master
> 
> As most kernel developers know, there's around ~10,000 main .h headers in 
> the Linux kernel, in the include/ and arch/*/include/ hierarchies. Over the 
> last 30+ years they have grown into a complicated & painful set of 
> cross-dependencies we are affectionately calling 'Dependency Hell'.

In the 64e013748e61 ("headers/deps: Optimize <linux/kernel.h>")
the linux/container_of.h and linux/stdarg.h are moved around (in the
linux/kernel.h) without any explanation in the commit message. Is it
necessary? If so, can you add a background note.

-- 
With Best Regards,
Andy Shevchenko