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: Mark Davies <junk@eslaf.co.uk>
Suggested-by: Mark Davies <junk@eslaf.co.uk>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: fweisbec@gmail.com
Link: http://lkml.kernel.org/n/tip-69efsat90ibhnd577zy3z9gh@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 1246b85..895604f 100644 (file)
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/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;