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| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-02-19 10:51:42 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2014-05-13 11:18:18 -0700 |
| commit | ad0dc7f94dbf417b1c7d42e1f0b250f045b27f8f (patch) | |
| tree | 7ab989cc1da5014778a7bd24ec94184104e5b517 /kernel/rcu/tree.c | |
| parent | c9eaa447e77efe77b7fa4c953bd62de8297fd6c5 (diff) | |
| download | linux-ad0dc7f94dbf417b1c7d42e1f0b250f045b27f8f.tar.bz2 | |
rcutorture: Add forward-progress checking for writer
The rcutorture output currently does not distinguish between stalls in
the RCU implementation and stalls in the rcu_torture_writer() kthreads.
This commit therefore adds some diagnostics to help distinguish between
these two conditions, at least for the non-SRCU implementations. (SRCU
does not provide evidence of update-side forward progress by design.)
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcu/tree.c')
| -rw-r--r-- | kernel/rcu/tree.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 0c47e300210a..3d15b5a82ae8 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -294,6 +294,39 @@ void rcutorture_record_test_transition(void) EXPORT_SYMBOL_GPL(rcutorture_record_test_transition); /* + * Send along grace-period-related data for rcutorture diagnostics. + */ +void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags, + unsigned long *gpnum, unsigned long *completed) +{ + struct rcu_state *rsp = NULL; + + switch (test_type) { + case RCU_FLAVOR: + rsp = rcu_state; + break; + case RCU_BH_FLAVOR: + rsp = &rcu_bh_state; + break; + case RCU_SCHED_FLAVOR: + rsp = &rcu_sched_state; + break; + default: + break; + } + if (rsp != NULL) { + *flags = ACCESS_ONCE(rsp->gp_flags); + *gpnum = ACCESS_ONCE(rsp->gpnum); + *completed = ACCESS_ONCE(rsp->completed); + return; + } + *flags = 0; + *gpnum = 0; + *completed = 0; +} +EXPORT_SYMBOL_GPL(rcutorture_get_gp_data); + +/* * Record the number of writer passes through the current rcutorture test. * This is also used to correlate debugfs tracing stats with the rcutorture * messages. |