In the mips, mips64, and even the i386 arch, arch/kernel/smp.c has
this in smp_call_function:
spin_lock(&call_lock);
call_data = &data;
/* Send a message to all other CPUs and wait for them to respond */
for (i = 0; i < smp_num_cpus; i++)
if (i != cpu)
core_send_ipi(i, SMP_CALL_FUNCTION);
call_data isn't volatile, it's a plain static *. So how can we be sure
that "call_data = &data" does anything other than change a register?
The i386 has a wb() after the assignment; we don't even have that.
greg
