Date: Wed, 16 Nov 2016 09:13:55 +0100
From: Ingo Molnar <mingo@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg KH <gregkh@linuxfoundation.org>,
        Christoph Hellwig <hch@infradead.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Kees Cook <keescook@chromium.org>, Will Deacon <will.deacon@arm.com>,
        elena.reshetova@intel.com, Arnd Bergmann <arnd@arndb.de>,
        Thomas Gleixner <tglx@linutronix.de>, Peter Anvin <hpa@zytor.com>,
        dave@progbits.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] printk, locking/atomics, kref: Introduce new %pAr and
 %pAk format string options for atomic_t and 'struct kref'
Message-ID: <20161116081354.GB1270@gmail.com>
References: <20161114173946.501528675@infradead.org>
 <20161114174446.486581399@infradead.org>
 <20161114181655.GA21516@infradead.org>
 <20161115072855.GB28248@kroah.com>
 <20161115083736.GA15734@gmail.com>
 <CA+55aFz1QBi1Of3UUzc=6HWM7wPe7FaztoxKtCLuneuzu+4=YQ@mail.gmail.com>
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Tue, Nov 15, 2016 at 12:37 AM, Ingo Molnar <mingo@kernel.org> wrote:
> > +atomic variables such atomic_t or struct kref:
> > +
> > +       %pAr    atomic_t count
> > +       %pAk    struct kref count
> 
> Not a huge fan. That "r" makes sense to you ("raw" atomic), but it
> makes no sense to a user. An atomic isn't "raw" to anybody else. It's
> just an atomic.

So in the latestest patch this has evolved to:

        %pAa - print the 'atomic_t'    count in decimal
        %pAk - print the 'struct kref' count in decimal
        %pAr - print the 'refcount_t'  count in decimal

... are you still hating it?

> Also, we have 'atomic64_t", which this doesn't cover at all.

We could use a somewhat logical letter for atomic64_t too:

	%pAA - print the 'atomic64_t'  count in decimal

... as 'A' is the bigger version of 'a', just like atomic64_t is the bigger 
version of atomic_t! ;-)

> I'd suggest just %pA, %pA64, %pAkref or something. Which leaves us the
> choice to add more atomic versions later without having to make up
> random one-letter things that make no sense.

It's a bit more work, but we could do that too, if you still don't like the above 
single letter abbreviations.

Thanks,

	Ingo