Re: [PATCH] mm: Add new vma flag VM_LOCAL_CPU

[Peter Zijlstra]

On Tue, May 22, 2018 at 04:46:05PM +0000, Christopher Lameter wrote:
> On Tue, 22 May 2018, Dave Hansen wrote:
> 
> > On 05/22/2018 09:05 AM, Boaz Harrosh wrote:
> > > How can we implement "Private memory"?
> >
> > Per-cpu page tables would do it.
> 
> We already have that for percpu subsystem. See alloc_percpu()

x86 doesn't have per-cpu page tables. And the last time I looked, percpu
also didn't, it played games with staggered ranges in the vmalloc space
and used the [FG]S segment offset to make it work.

Doing proper per-cpu pagetables on x86 is possible, but quite involved
and expensive.