rcu: Make rcu_torture_fqs() exit loops at end of test
The rcu_torture_fqs() function can prevent the rcutorture tests from
completing, resulting in a hang. This commit therefore ensures that
rcu_torture_fqs() will exit its inner loops at the end of the test,
and also applies the newish ULONG_CMP_LT() macro to time comparisons.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index ade7771..2431d576 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -741,7 +741,7 @@
do {
/* Wait for the next test interval. */
oldstarttime = boost_starttime;
- while (jiffies - oldstarttime > ULONG_MAX / 2) {
+ while (ULONG_CMP_LT(jiffies, oldstarttime)) {
schedule_timeout_uninterruptible(1);
rcu_stutter_wait("rcu_torture_boost");
if (kthread_should_stop() ||
@@ -752,7 +752,7 @@
/* Do one boost-test interval. */
endtime = oldstarttime + test_boost_duration * HZ;
call_rcu_time = jiffies;
- while (jiffies - endtime > ULONG_MAX / 2) {
+ while (ULONG_CMP_LT(jiffies, endtime)) {
/* If we don't have a callback in flight, post one. */
if (!rbi.inflight) {
smp_mb(); /* RCU core before ->inflight = 1. */
@@ -818,11 +818,13 @@
VERBOSE_PRINTK_STRING("rcu_torture_fqs task started");
do {
fqs_resume_time = jiffies + fqs_stutter * HZ;
- while (jiffies - fqs_resume_time > LONG_MAX) {
+ while (ULONG_CMP_LT(jiffies, fqs_resume_time) &&
+ !kthread_should_stop()) {
schedule_timeout_interruptible(1);
}
fqs_burst_remaining = fqs_duration;
- while (fqs_burst_remaining > 0) {
+ while (fqs_burst_remaining > 0 &&
+ !kthread_should_stop()) {
cur_ops->fqs();
udelay(fqs_holdoff);
fqs_burst_remaining -= fqs_holdoff;