[PATCH 2/5] stop_machine: yield CPU during stop machine

Christian Borntraeger
2016-10-21T12:00:32Z

stop_machine can take a very long time if the hypervisor does
overcommitment for guest CPUs. When waiting for "the one", lets
give up our CPU by using the new cpu_relax_yield.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
kernel/stop_machine.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index ec9ab2f..1eb8266 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -194,7 +194,7 @@ static int multi_cpu_stop(void *data)
/* Simple state machine */
do {
/* Chill out and ensure we re-read multi_stop_state. */
- cpu_relax();
+ cpu_relax_yield();
if (msdata->state != curstate) {
curstate = msdata->state;
switch (curstate) {
--
2.5.5