[PATCH v6 15/46] tick: Use get/put_online_cpus_atomic() to prevent CPU offline
From: Srivatsa S. Bhat <hidden>
Date: 2013-02-18 12:42:33
Also in:
linux-arch, linux-arm-kernel, linux-pm, lkml, netdev
Subsystem:
nohz, dynticks support, the rest · Maintainers:
Anna-Maria Behnsen, Frederic Weisbecker, Ingo Molnar, Thomas Gleixner, Linus Torvalds
Once stop_machine() is gone from the CPU offline path, we won't be able to depend on preempt_disable() or local_irq_disable() to prevent CPUs from going offline from under us. Use the get/put_online_cpus_atomic() APIs to prevent CPUs from going offline, while invoking from atomic context. Signed-off-by: Srivatsa S. Bhat <redacted> --- kernel/time/tick-broadcast.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index f113755..d123a2c 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c@@ -160,6 +160,7 @@ static void tick_do_broadcast(struct cpumask *mask) */ static void tick_do_periodic_broadcast(void) { + get_online_cpus_atomic(); raw_spin_lock(&tick_broadcast_lock); cpumask_and(to_cpumask(tmpmask),
@@ -167,6 +168,7 @@ static void tick_do_periodic_broadcast(void) tick_do_broadcast(to_cpumask(tmpmask)); raw_spin_unlock(&tick_broadcast_lock); + put_online_cpus_atomic(); } /*