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Date: Fri, 30 Jul 2004 20:47:21 +0200
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From: Takashi Iwai <tiwai@suse.de>
To: Jeff Garzik <jgarzik@pobox.com>
Cc: Andi Kleen <ak@suse.de>, akpm@osdl.org, linux-kernel@vger.kernel.org,
       James.Bottomley@HansenPartnership.com
Subject: Re: [PATCH] Improve pci_alloc_consistent wrapper on preemptive kernels
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At Fri, 30 Jul 2004 14:07:57 -0400,
Jeff Garzik wrote:
> 
> Andi Kleen wrote:
> > On Fri, 30 Jul 2004 13:16:28 -0400
> > Jeff Garzik <jgarzik@pobox.com> wrote:
> > 
> > 
> > 
> >>1) Changing from GFP_ATOMIC to <something else> may break code
> > 
> > 
> > x86-64 did it for a long time and I am not aware of problems with it
> > (however I don't know how widespread CONFIG_PREEMPT use on x86-64 is) 
> > 
> > 
> >>2) Conversely from #1, I also worry why GFP_ATOMIC would be needed at 
> >>all.  I code all my drivers to require that pci_alloc_consistent() be 
> >>called from somewhere that is allowed to sleep.
> > 
> > 
> > Maybe you do, but others don't.
> 
> Certainly.  Therefore, changing from GFP_ATOMIC will increase likelihood 
> of breakage, no?

pci_alloc_consistent() was GFP_ATOMIC only on 2.4 anyway, so I don't
expect there would be any breakage...


Takashi