[patch V2 05/24] x86/mtrr: Remove get_online_cpus() from mtrr_save_state()

Thomas Gleixner
2017-04-18T19:49:52Z

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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

mtrr_save_state() is invoked from native_cpu_up() which is in the context
of a CPU hotplug operation and therefor calling get_online_cpus() is
pointless.

While this works in the current get_online_cpus() implementation it
prevents from converting the hotplug locking to percpu rwsems.

Remove it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: x86@kernel.org

---
arch/x86/kernel/cpu/mtrr/main.c | 2 --
1 file changed, 2 deletions(-)

--- a/arch/x86/kernel/cpu/mtrr/main.c
+++ b/arch/x86/kernel/cpu/mtrr/main.c
@@ -807,10 +807,8 @@ void mtrr_save_state(void)
if (!mtrr_enabled())
return;

- get_online_cpus();
first_cpu = cpumask_first(cpu_online_mask);
smp_call_function_single(first_cpu, mtrr_save_fixed_ranges, NULL, 1);
- put_online_cpus();
}

void set_mtrr_aps_delayed_init(void)