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Date: Tue, 26 May 2009 06:32:35 -0500
Message-ID: <ed82fe3e0905260432xdc9556cp74edc723eafe24f7@mail.gmail.com>
Subject: Re: [PATCH V4 1/5] The macro spin_event_timeout() takes a condition
	and timeout value
From: Timur Tabi <timur@freescale.com>
To: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
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On Tue, May 26, 2009 at 2:29 AM, Geert Uytterhoeven
<Geert.Uytterhoeven@sonycom.com> wrote:

> static inline function, returning rc, instead of a macro?

It won't work as an inline function ...

>> + =A0 =A0 unsigned long __loops =3D tb_ticks_per_usec * timeout; =A0 =A0=
 =A0 =A0 =A0 =A0 =A0 =A0\
>> + =A0 =A0 unsigned long __start =3D get_tbl(); =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0\
>> + =A0 =A0 while ((rc =3D (condition)) && (tb_ticks_since(__start) <=3D _=
_loops)) \

There's no way to pass a expression to an inline function.  It has to
be a macro.  Here, the loop evaluates "condition" at every pass.  If
this were an inline function, "condition" would be evaluated once when
the function were called, and never again.

--=20
Timur Tabi
Linux kernel developer at Freescale