diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-07-25 05:50:40 +0200 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2018-08-29 18:20:48 +0200 |
| commit | f4de46ed5bbc8ba9acebc8ac75809751b716e470 (patch) | |
| tree | 0cdda95c3df98eae1e057288762f7e2b442f44d8 /kernel/rcu | |
| parent | rcutorture: Adjust number of reader kthreads per CPU-hotplug operations (diff) | |
| download | linux-f4de46ed5bbc8ba9acebc8ac75809751b716e470.tar.xz linux-f4de46ed5bbc8ba9acebc8ac75809751b716e470.zip | |
rcutorture: Print forward-progress test interval on error
This commit prints the duration of the forward-progress test interval in
the case that no forward progress was observed as an aid to debugging.
When forward progress does happen, it prints out the number of
rcu_torture_writer() versions and grace periods that elapsed during the
forward-progress test. At the end of the run, it also prints the number
of attempted and actual forward-progress tests.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/rcutorture.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 50015b78a43f..7df8142a6a22 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -1702,6 +1702,7 @@ static void rcu_torture_fwd_prog_cb(struct rcu_head *rhp) static int rcu_torture_fwd_prog(void *args) { unsigned long cver; + unsigned long dur; struct fwd_cb_state fcs = { .stop = 0 }; unsigned long gps; int idx; @@ -1709,7 +1710,7 @@ static int rcu_torture_fwd_prog(void *args) int sd4; bool selfpropcb = false; unsigned long stopat; - bool tested = false; + int tested = 0; int tested_tries = 0; static DEFINE_TORTURE_RANDOM(trs); @@ -1727,7 +1728,8 @@ static int rcu_torture_fwd_prog(void *args) gps = cur_ops->get_gp_seq(); sd = cur_ops->stall_dur() + 1; sd4 = (sd + fwd_progress_div - 1) / fwd_progress_div; - stopat = jiffies + sd4 + torture_random(&trs) % (sd - sd4); + dur = sd4 + torture_random(&trs) % (sd - sd4); + stopat = jiffies + dur; while (time_before(jiffies, stopat) && !torture_must_stop()) { idx = cur_ops->readlock(); udelay(10); @@ -1737,10 +1739,11 @@ static int rcu_torture_fwd_prog(void *args) } tested_tries++; if (!time_before(jiffies, stopat) && !torture_must_stop()) { - tested = true; - cver = cver == READ_ONCE(rcu_torture_current_version); + tested++; + cver = READ_ONCE(rcu_torture_current_version) - cver; gps = rcutorture_seq_diff(cur_ops->get_gp_seq(), gps); - WARN_ON_ONCE(cver && gps < 2); + WARN_ON(!cver && gps < 2); + pr_alert("%s: Duration %ld cver %ld gps %ld\n", __func__, dur, cver, gps); } /* Avoid slow periods, better to test when busy. */ stutter_wait("rcu_torture_fwd_prog"); @@ -1754,6 +1757,7 @@ static int rcu_torture_fwd_prog(void *args) } /* Short runs might not contain a valid forward-progress attempt. */ WARN_ON(!tested && tested_tries >= 5); + pr_alert("%s: tested %d tested_tries %d\n", __func__, tested, tested_tries); torture_kthread_stopping("rcu_torture_fwd_prog"); return 0; } |