Re: [patch 0/7] [RFC] SLUB: Improve allocpercpu to reduce per cpuaccess overhead
From: David Miller
Date: Thu Nov 01 2007 - 17:28:22 EST
From: Christoph Lameter <clameter@xxxxxxx>
Date: Thu, 1 Nov 2007 05:57:12 -0700 (PDT)
> That is basically what IA64 is doing but it not usable because you would
> have addresses that mean different things on different cpus. List head
> for example require back pointers. If you put a listhead into such a per
> cpu area then you may corrupt another cpus per cpu area.
Indeed, but as I pointed out in another mail it actually works if you
set some rules:
1) List insert and delete is only allowed on local CPU lists.
2) List traversal is allowed on remote CPU lists.
I bet we could get all of the per-cpu users to abide by this
rule if we wanted to.
The remaining issue with accessing per-cpu areas at multiple virtual
addresses is D-cache aliasing.
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