From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: >Re: [RFC] should VM_BUG_ON(cond) really evaluate cond
Date: Sun, 30 Oct 2011 18:41:34 +0100
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Cc: Andi Kleen <andi@firstfloor.org>,
	Ben Hutchings <bhutchings@solarflare.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Le dimanche 30 octobre 2011 =C3=A0 10:07 -0700, Linus Torvalds a =C3=A9=
crit :
> On Sun, Oct 30, 2011 at 8:16 AM, Eric Dumazet <eric.dumazet@gmail.com=
> wrote:
> >
> > Because it doesnt work if x is const.
>=20
> Just remove the const. Problem solved.
>=20
> Both cases of 'const' are totally arbitrary and useless. The
> test_bit() one is literally a cast to const (admittedly also *from*
> const, but nobody cares), and the atomic_read() one is just because i=
t
> uses a silly inline function where a macro would be simpler.
>=20

Oh well, I am lost. I always considered inline functione better because
of prototype checks.


Changing atomic_read(const atomic_t *v) prototype to
atomic_read(atomic_t *v) is not an option.


To save your time and my time, please select your favorite between :

1) The patch I did

2)=20
 static inline int atomic_read(const atomic_t *v)
 {
	return ACCESS_AT_MOST_ONCE(((atomic_t *)v)->counter);
 }

3)=20
 static inline int atomic_read(const atomic_t *v)
 {
	return ACCESS_AT_MOST_ONCE(*(int *)&(v)->counter);
 }

4) macro (I personnaly dont like it)
#define atomic_read(v) ACCESS_AT_MOST_ONCE(*(int *)&(v)->counter)

Thanks