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Date: Thu, 22 Sep 2011 23:54:17 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Colin Cross <ccross@android.com>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>, Ingo Molnar <mingo@elte.hu>,
        Peter Zijlstra <peterz@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Alexey Dobriyan <adobriyan@gmail.com>
Subject: Re: [PATCH 1/3] fs: seq_file: add seq_reserve
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On Thu, 22 Sep 2011 13:57:07 -0700
Colin Cross <ccross@android.com> wrote:

> Adds a seq_reserve function to allow users of the seq_file interface to
> increase the initial size of the buffer.  Avoids repeated allocations and
> calls to the show function in cases where large buffers of known size are
> needed.

Would it not be better to have something akin to


	void seq_set_buffer(struct seq_file *m, void *ptr, size_t size)
	{
		m->buf = ptr;
		m->size = size;
		m->private = 1;
	}

and let the caller simply provide a buffer by any means it wishes (even
statically) and free it again itself. That keeps the caller fully in
control when it wishes to be.

Alan