Date: Wed, 15 Feb 2012 13:34:11 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
To: Xi Wang <xi.wang@gmail.com>
cc: Pekka Enberg <penberg@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Jesper Juhl <jj@chaosbits.net>, Jens Axboe <axboe@kernel.dk>,
        linux-kernel@vger.kernel.org, Matt Mackall <mpm@selenic.com>,
        David Rientjes <rientjes@google.com>
Subject: Re: Uninline kcalloc
In-Reply-To: <07635976-4FC3-4E14-9B94-CE4D6446FD4E@gmail.com>
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On Wed, 15 Feb 2012, Xi Wang wrote:

> for overflow, one has to write:
>
>         size_t s = calculate_array_size(n, size);
>         if (s)
>                 p = kmalloc(s, ...);
>
> This "if" thing is just too verbose --- you need three lines to
> allocate an array.
>
> We could change calculate_array_size() to return ULONG_MAX or some
> large number with which kmalloc() would fail.  Then one would write:

Any allocation larger than MAX_ORDER << PAGE_SHIFT will fail since the
page allocator cannot serve larger contigous pages.


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