From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Date: Thu, 25 Apr 2002 01:01:59 +0000 Subject: [Linux-ia64] Re: PCI DAC routines for SN Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Wed, Apr 24, 2002 at 05:43:18PM -0700, David S. Miller wrote: > We don't add things to Linux that we "might need" we add things > we actually need. It is a slight performance problem too. I fully understand and agree with that, and I don't propose adding the call just for the fun of it. It's just that most of the time, it's easier software-wise to use the 64 bit consistent mappings if your device can support it (e.g. generic ia64, ia64/sn). > I don't think the hardware folks would be happy to hear that you're > willing to sacrifice real hardware cycles just for some DAC nirvana > or whatever it is you have for this issue. I don't think the performance impact of those extra cycles would be measurable, but I'd be happy to see any numbers you might have to the contrary. Jesse