[PATCH v5 15/45] tick: Use get/put_online_cpus_atomic() to prevent CPU offline
Srivatsa S. Bhat
srivatsa.bhat at linux.vnet.ibm.com
Tue Jan 22 02:36:55 EST 2013
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 <srivatsa.bhat at linux.vnet.ibm.com>
---
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();
}
/*
More information about the linux-arm-kernel
mailing list