Some of the Linux kernel's RCU implementations provide several mechanisms to promote forward progress that operate over different timeframes. This commit therefore causes rcu_torture_fwd_prog() to vary the duration of its forward-progress testing in order to test each such mechanism.
Signed-off-by: Paul E. McKenney <[email protected]> --- kernel/rcu/rcutorture.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 8ab23143c244..89cc4d9c9a0c 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1676,16 +1676,21 @@ static int rcu_torture_fwd_prog(void *args) unsigned long cver; unsigned long gps; int idx; + int sd; + int sd4; unsigned long stopat; bool tested = false; int tested_tries = 0; + static DEFINE_TORTURE_RANDOM(trs); VERBOSE_TOROUT_STRING("rcu_torture_fwd_progress task started"); do { schedule_timeout_interruptible(fwd_progress_holdoff * HZ); cver = READ_ONCE(rcu_torture_current_version); gps = cur_ops->get_gp_seq(); - stopat = jiffies + cur_ops->stall_dur() / fwd_progress_div; + sd = cur_ops->stall_dur() + 1; + sd4 = (sd + fwd_progress_div - 1) / fwd_progress_div; + stopat = jiffies + sd4 + torture_random(&trs) % (sd - sd4); while (time_before(jiffies, stopat) && !torture_must_stop()) { idx = cur_ops->readlock(); udelay(10); -- 2.17.1
