[tip:smp/hotplug] x86/mtrr: Remove get_online_cpus() from mtrr_save_state()

tip-bot for Sebastian Andrzej Siewior
2017-04-20T11:23:32Z

Commit-ID: 9ef0b62e7059e3ea85e2e5c4894bc2cb78b04eed
Gitweb: http://git.kernel.org/tip/9ef0b62e7059e3ea85e2e5c4894bc2cb78b04eed
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate: Tue, 18 Apr 2017 19:04:47 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 20 Apr 2017 13:08:51 +0200

x86/mtrr: Remove get_online_cpus() from mtrr_save_state()

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: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170418170552.775914295@linutronix.de

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

diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c
index 24e87e7..8fd1f8d 100644
--- 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)