canonical address (l-value).  To get the virtually mapped
	alias (which is more efficient), use __ia64_per_cpu_var().  The
	latter is safe only if the address of the l-value is never passed
	to another CPU (i.e., not stored in any global place).
	For extremely efficient, portable per-CPU variables, there is
	now a new API local.h which was introduced by Rusty Russell.
	To use this, declare a variable of type local_t as a per-CPU
	variable and then use {__,}cpu_local_FOO() to manipulate such
	variables.  This patch also updated the atomic interface with
	a 64-bit counter.