Re: GFP_DMA32 and PAE x86 machines

2007-05-31 Thread Andi Kleen
> Funnily enough I have just today with an app I have which uses 1.2GB > of textures :-) Realistic app which is something users really run? Also do the other constraints above apply? If you use pci_alloc_coherent() then it will already take care of the rules above btw (e.g. DTRT when the machine

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread William Lee Irwin III
On 5/31/07, Andi Kleen <[EMAIL PROTECTED]> wrote: >> Please give a very very strong rationale why you want it. Did you actually >> run into such a situation yourself yet? On Thu, May 31, 2007 at 09:09:58AM +1000, Dave Airlie wrote: > Funnily enough I have just today with an app I have which uses 1

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread Dave Airlie
On 5/31/07, Andi Kleen <[EMAIL PROTECTED]> wrote: On Thursday 31 May 2007 00:07:45 Dave Airlie wrote: > Depending on split all lowmem is below 1GB which isn't exactly > optimal, I'd llike all 4GB for DMA. Well it would be for a quite specialized limited use case: - Memory the kernel doesn't need

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread H. Peter Anvin
Andi Kleen wrote: > On Thursday 31 May 2007 00:07:45 Dave Airlie wrote: >> Depending on split all lowmem is below 1GB which isn't exactly >> optimal, I'd llike all 4GB for DMA. > > Well it would be for a quite specialized limited use case: > - Memory the kernel doesn't need to map (after all kmap

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread Andi Kleen
On Thursday 31 May 2007 00:07:45 Dave Airlie wrote: > Depending on split all lowmem is below 1GB which isn't exactly > optimal, I'd llike all 4GB for DMA. Well it would be for a quite specialized limited use case: - Memory the kernel doesn't need to map (after all kmap is evil) - You need more t

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread H. Peter Anvin
Dave Airlie wrote: > Depending on split all lowmem is below 1GB which isn't exactly > optimal, I'd llike all 4GB for DMA. Yes, but creating new memory zones is expensive. -hpa - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROT

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread Dave Airlie
Depending on split all lowmem is below 1GB which isn't exactly optimal, I'd llike all 4GB for DMA. Dave. On 5/31/07, H. Peter Anvin <[EMAIL PROTECTED]> wrote: Dave Airlie wrote: > Just a question, > > So we have GFP_DMA32 on x86-64 to gives us memory below 4G? so we not > have the same on PAE b

Re: GFP_DMA32 and PAE x86 machines

2007-05-30 Thread H. Peter Anvin
Dave Airlie wrote: > Just a question, > > So we have GFP_DMA32 on x86-64 to gives us memory below 4G? so we not > have the same on PAE based x86 machines so I can use a consistent API > from the drm? > > Otherwise it'll be stick some ifdefs in the drm to deal with it.. > Well, all lowmem is bel