per-cpu data...

[Rusty Russell <rusty@rustcorp.com.au>]

IIUC, __per_cpu_data is insufficient for Alpha as stands, to use
thread-specific gcc tricks (__thread prepended to the decl, even
though they had a perfectly good __attribute__ extension already).

So, I guess we're stuck with something like:

DECLARE_PER_CPU(int x);

If we're going to do this, we can also mangle the name as well to
avoid accidental "direct" accesses:

eg:
	#define DECLARE_PER_CPU(var) 
		var##__percpu __attribute__((section(".percpu")))

	/* If not SMP: */
	#define per_cpu(var) var##__percpu

(From my reading, ## on "int x" and "__per_cpu" is well-defined).

Thoughts?
Rusty.
--
  Anyone who quotes me in their sig is an idiot. -- Rusty Russell.