From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
Subject: Re: [RFC PATCH] libata: PIO via bounce buffer
Date: Sat, 1 Mar 2008 16:38:03 +0000
Message-ID: <20080301163803.2ff1d1bc@core>
References: <20080229135106.4fcf19e3@core>
	<47C8A2C0.7070005@garzik.org>
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To: Jeff Garzik <jeff@garzik.org>
Cc: linux-ide@vger.kernel.org

> Inside ata_bounce_pio_xfer(), get the buffer for your CPU.  If NULL or 
> too small, allocate new buffer, otherwise re-use existing buffer.
> 
> This method makes the common case _not_ allocate anything, which should 
> be obviously more efficient.

Obviously ?

kmalloc will usually return us a cache hot buffer very very fast. A
private allocator will return us an almost certainly cache cold buffer
slightly faster.

I'm not sure its that simple.

Alan