Re: [guv v2 04/31] net: Replace __get_cpu_var uses

[David Howells]

David Miller <davem@xxxxxxxxxxxxx> wrote:

> > Would it be possible to use __thread annotations for per-CPU
> > variables, I wonder?
> 
> Paul Mackerras tried it on powerpc and you can't do it.
> 
> The problem is that there is no way to tell the compiler that sched()
> and similar (potentially) change the thread pointer base.
> 
> It really will cache pre-computed __thread pointer calculations across
> sched().

Yeah...  I thought there might be something like that - but I could see x86_64
using %fs as a base.

David
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