Messages in this thread | | | Date | Fri, 25 Jul 2008 01:42:52 -0700 (PDT) | Subject | Re: recent IDE regression | From | David Miller <> |
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From: Ben Dooks <ben-linux@fluff.org> Date: Fri, 25 Jul 2008 09:34:48 +0100
> On Thu, Jul 24, 2008 at 11:38:31PM -0700, David Miller wrote: > > diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c > > index 07da5fb..8aae917 100644 > > --- a/drivers/ide/ide-iops.c > > +++ b/drivers/ide/ide-iops.c > > @@ -510,10 +510,8 @@ void ide_fixstring (u8 *s, const int bytecount, const int byteswap) > > > > if (byteswap) { > > /* convert from big-endian to host byte order */ > > - for (p = end ; p != s;) { > > - unsigned short *pp = (unsigned short *) (p -= 2); > > - *pp = ntohs(*pp); > > - } > > + for (p = end ; p != s;) > > + be16_to_cpus((u16 *)(p -= 2)); > > personally, i would much prefer to see the loop being less evil > like: > > for (p = s; p < end; p += 2) > be16_to_cpus((u16 *)p); > > is there an architecture/compiler combo which really makes this > evil worthwile? on arm (gcc 4.2), both evaluate to the same number of > instructions.
Regardless of what we want to do with this ugly loop, the endianness macros should be fixed to consistently evaluate their arguments once just like real function calls do.
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