perf/x86: Fix Userspace RDPMC switch

The current code forgets to change the CR4 state on the current CPU.
Use on_each_cpu() instead of smp_call_function().
Reported-by: NMark Davies <junk@eslaf.co.uk>
Suggested-by: NMark Davies <junk@eslaf.co.uk>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/n/tip-69efsat90ibhnd577zy3z9gh@git.kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/perf_event.c

@@ -1826,7 +1826,7 @@ static ssize_t set_attr_rdpmc(struct device *cdev,
 
 	if (!!val != !!x86_pmu.attr_rdpmc) {
 		x86_pmu.attr_rdpmc = !!val;
-		smp_call_function(change_rdpmc, (void *)val, 1);
+		on_each_cpu(change_rdpmc, (void *)val, 1);
 	}
 
 	return count;