Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / arch / x86 / oprofile / nmi_int.c

diff --git a/arch/x86/oprofile/nmi_int.c b/arch/x86/oprofile/nmi_int.c
index cf97500..68894fd 100644 (file)
--- a/arch/x86/oprofile/nmi_int.c
+++ b/arch/x86/oprofile/nmi_int.c
@@ -112,8 +112,10 @@ static void nmi_cpu_start(void *dummy)
 static int nmi_start(void)
 {
        get_online_cpus();
-       on_each_cpu(nmi_cpu_start, NULL, 1);
        ctr_running = 1;
+       /* make ctr_running visible to the nmi handler: */
+       smp_mb();
+       on_each_cpu(nmi_cpu_start, NULL, 1);
        put_online_cpus();
        return 0;
 }
@@ -504,15 +506,18 @@ static int nmi_setup(void)
 
        nmi_enabled = 0;
        ctr_running = 0;
-       barrier();
+       /* make variables visible to the nmi handler: */
+       smp_mb();
        err = register_die_notifier(&profile_exceptions_nb);
        if (err)
                goto fail;
 
        get_online_cpus();
        register_cpu_notifier(&oprofile_cpu_nb);
-       on_each_cpu(nmi_cpu_setup, NULL, 1);
        nmi_enabled = 1;
+       /* make nmi_enabled visible to the nmi handler: */
+       smp_mb();
+       on_each_cpu(nmi_cpu_setup, NULL, 1);
        put_online_cpus();
 
        return 0;
@@ -531,7 +536,8 @@ static void nmi_shutdown(void)
        nmi_enabled = 0;
        ctr_running = 0;
        put_online_cpus();
-       barrier();
+       /* make variables visible to the nmi handler: */
+       smp_mb();
        unregister_die_notifier(&profile_exceptions_nb);
        msrs = &get_cpu_var(cpu_msrs);
        model->shutdown(msrs);