Re: [guv v2 04/31] net: Replace __get_cpu_var uses
From: David Miller <davem@davemloft.net>
Date: 2013-09-03 03:28:00
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From: David Howells <dhowells@redhat.com> Date: Mon, 02 Sep 2013 22:35:06 +0100
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().