Re: question regarding cacheline size

[Jeff Garzik]

Tejun Heo wrote:
> arch/i386/pci/common.c overrides cacheline size to min 32 regardless of 
> actual size.  So, we seem to be using larger cacheline size for MWI 
> already.

It clamps the minimum size to 32, yes, but on modern machines common.c 
configures it to a larger size.


> Jeff pointed out that there actually are devices which limit CLS config. 
>  IMHO, making PCI configure CLS automatically and provide helpers to LLD 
> to override it if necessary should cut it.

We still have to add a raft of quirks, if we start automatically 
configurating CLS...  Also, many PCI devices hardcode it to zero.

If we start configuring CLS automatically, I forsee a period of breakage...

	Jeff


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