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Subject: Re: [PATCH RFC v2] slab: introduce kmalloc_array
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From: Xi Wang <xi.wang@gmail.com>
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Date: Tue, 14 Feb 2012 06:12:06 -0500
Cc: Christoph Lameter <cl@linux.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jesper Juhl <jj@chaosbits.net>, Jens Axboe <axboe@kernel.dk>,
        Pekka Enberg <penberg@kernel.org>, linux-kernel@vger.kernel.org,
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To: Dan Carpenter <dan.carpenter@oracle.com>
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On Feb 14, 2012, at 2:20 AM, Dan Carpenter wrote:
> I really think that's over thinking things.  Let's just match
> kcalloc() exactly except without zeroing.  The BUILD_BUG_ON() thing
> is an over complication as well.  We haven't needed it for
> kcalloc().

I don't think the BUILD_BUG_ON macro is useful here nor in kcalloc
(besides gcc won't give you much handy information).

Just matching the new non-zeroing array allocator with kcalloc seems
like the right thing to do.  We had quite a few patches that could
be simpler with it.  For now I don't feel like it's necessary to
change the API (e.g., making gfp_t as the first argument), do "smart"
optimizations (e.g., recognizing the first argument is a constant),
nor add more allocators (e.g., to match vmalloc, kmalloc_node).

- xi