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To: "Bryan O'Sullivan" <bos@pathscale.com>
Cc: Andrew Morton <akpm@osdl.org>, Sam Ravnborg <sam@ravnborg.org>,
       hch@infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1 of 3] Introduce __raw_memcpy_toio32
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From: Roland Dreier <rdreier@cisco.com>
Date: Wed, 11 Jan 2006 11:01:39 -0800
In-Reply-To: <1137005865.11245.47.camel@camp4.serpentine.com> (Bryan
 O'Sullivan's message of "Wed, 11 Jan 2006 10:57:45 -0800")
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    Bryan> The memcpy32 routine is, but __raw_memcpy_toio32 simply
    Bryan> calls it, so we have two jump/ret pairs instead of one.

Oh, I think you're misunderstanding Andrew's idea.  Just create a
generic __raw_memcpy_toio32() that is always compiled, but mark it
with attribute((weak)).  Then x86_64 can define its own version of
__raw_memcpy_toio32(), which will override the weak generic version.

 - R.