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Date: Fri, 8 Nov 2013 11:25:02 -0500
From: Neil Horman <nhorman@tuxdriver.com>
To: Joe Perches <joe@perches.com>
Cc: Dave Jones <davej@redhat.com>, linux-kernel@vger.kernel.org,
        sebastien.dugue@bull.net, Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
        x86@kernel.org
Subject: Re: [PATCH v2 2/2] x86: add prefetching to do_csum
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On Wed, Nov 06, 2013 at 12:07:38PM -0800, Joe Perches wrote:
> On Wed, 2013-11-06 at 15:02 -0500, Neil Horman wrote:
> > On Wed, Nov 06, 2013 at 09:19:23AM -0800, Joe Perches wrote:
> []
> > > __always_inline instead of inline
> > > static __always_inline void prefetch_lines(const void *addr, size_t len)
> > > {
> > > 	const void *end = addr + len;
> > > ...
> > > 
> > > buff doesn't need a void * cast in prefetch_lines
> > > 
> > Actually I take back what I said here, we do need the cast, not for a conversion
> > from unsigned char * to void *, but rather to discard the const qualifier
> > without making the compiler complain.
> 
> Not if the function is changed to const void *
> and end is also const void * as shown.
> 
Addr is incremented in the for loop, so it can't be const.  I could add a loop
counter variable on the stack, but that doesn't seem like it would help anything

Neil

> 
>