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| author | Paul E. McKenney <paulmck@linux.ibm.com> | 2018-12-10 18:44:52 +0100 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.ibm.com> | 2019-01-26 00:37:10 +0100 |
| commit | 3a6cb58f159e64241b2af9374acad41a70939349 (patch) | |
| tree | ada940f453392a61ee945b23974647841ee65700 /kernel/rcu | |
| parent | torture: Explain and simplify odd "for" loop in mkinitrd.sh (diff) | |
| download | linux-3a6cb58f159e64241b2af9374acad41a70939349.tar.xz linux-3a6cb58f159e64241b2af9374acad41a70939349.zip | |
rcutorture: Add grace period after CPU offline
Beyond a certain point in the CPU-hotplug offline process, timers get
stranded on the outgoing CPU, and won't fire until that CPU comes back
online, which might well be never. This commit therefore adds a hook
in torture_onoff_init() that is invoked from torture_offline(), which
rcutorture uses to occasionally wait for a grace period. This should
result in failures for RCU implementations that rely on stranded timers
eventually firing in the absence of the CPU coming back online.
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/rcutorture.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 0955f3a20952..9eb9235c1ec9 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -2243,6 +2243,14 @@ static void rcu_test_debug_objects(void) #endif /* #else #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ } +static void rcutorture_sync(void) +{ + static unsigned long n; + + if (cur_ops->sync && !(++n & 0xfff)) + cur_ops->sync(); +} + static int __init rcu_torture_init(void) { @@ -2404,7 +2412,8 @@ rcu_torture_init(void) firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup); if (firsterr) goto unwind; - firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval); + firsterr = torture_onoff_init(onoff_holdoff * HZ, onoff_interval, + rcutorture_sync); if (firsterr) goto unwind; firsterr = rcu_torture_stall_init(); |