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Date: Fri, 30 Jul 2004 13:02:38 -0700
From: Andrew Morton <akpm@osdl.org>
To: Andi Kleen <ak@suse.de>
Cc: linux-kernel@vger.kernel.org, James.Bottomley@HansenPartnership.com
Subject: Re: [PATCH] Improve pci_alloc_consistent wrapper on preemptive
 kernels
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Andi Kleen <ak@suse.de> wrote:
>
> This is a minor optimization for the pci_alloc_consistent wrapper for
>  the generic dma API. When the kernel is compiled preemptive the caller
>  can decide if the allocation needs to be GFP_KERNEL or GFP_ATOMIC.

We're paying for past sins here.  I think it would be better to create a
new version of pci_alloc_consistent() which takes gfp_flags, then migrate
the drivers you care about to use it.  That way the benefit is available on
non-preempt kernels too.

The ultimate aim of course would be to deprecate then remove the old
function.