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Date: Wed, 16 Apr 2008 14:34:26 -0400
From: Masami Hiramatsu <mhiramat@redhat.com>
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To: Pekka J Enberg <penberg@cs.helsinki.fi>
CC: Tom Zanussi <zanussi@comcast.net>, David Wilder <dwilder@us.ibm.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       systemtap-ml <systemtap@sources.redhat.com>,
       LKML <linux-kernel@vger.kernel.org>, tzanussi@gmail.com
Subject: Re: [PATCH -mm] relayfs: support larger relay buffer take 2
References: <4804C95F.2080204@redhat.com> <1208319769.7893.16.camel@charm-linux> <48063F80.9060404@redhat.com> <Pine.LNX.4.64.0804162110070.19171@sbz-30.cs.Helsinki.FI>
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Hi,

Pekka J Enberg wrote:
> Hi Masami,
> 
> On Wed, 16 Apr 2008, Masami Hiramatsu wrote:
>> +static struct page *relay_alloc_page_array(unsigned int n_pages)
>> +{
>> +	struct page *array;
>> +	unsigned int pa_size = n_pages * sizeof(struct page *);
>> +
>> +	if (pa_size > PAGE_SIZE) {
>> +		array = vmalloc(pa_size);
>> +		if (array)
>> +			memset(array, 0, pa_size);
>> +	} else {
>> +		array = kcalloc(n_pages, sizeof(struct page *), GFP_KERNEL);
>> +	}
>> +	return array;
>> +}
> 
> I think it's bit confusing to have relay_alloc_page_array() return a 
> pointer to struct page as it's really allocating an _array_ of pointers to 
> struct page. So why not just use void * here as the kernel memory 
> allocators do?

Thank you very much, it was my mistake.
It should return struct page **.

>> +static void relay_free_page_array(struct page *array)
>> +{
>> +	if (is_vmalloc_addr(array))
>> +		vfree(array);
>> +	else
>> +		kfree(array);
>> +}
> 
> Here as well.

Thanks,


-- 
Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division

e-mail: mhiramat@redhat.com