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| author | Paul E. McKenney <paul.mckenney@linaro.org> | 2011-10-02 07:44:32 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2011-12-11 10:31:26 -0800 |
| commit | 91afaf300269aa99a4d646969b3258b74294ac4d (patch) | |
| tree | b4d7dd5f5c9933be7873b206624f7b55eb25d906 /kernel | |
| parent | a8eecf2248a45bf69f0625b23c003ad2ccd765ee (diff) | |
| download | linux-91afaf300269aa99a4d646969b3258b74294ac4d.tar.bz2 | |
rcu: Add failure tracing to rcutorture
Trace the rcutorture RCU accesses and dump the trace buffer when the
first failure is detected.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/rcupdate.c | 10 | ||||
| -rw-r--r-- | kernel/rcutorture.c | 18 |
2 files changed, 28 insertions, 0 deletions
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index c5b98e565aee..92e771d7b44b 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -316,3 +316,13 @@ struct debug_obj_descr rcuhead_debug_descr = { }; EXPORT_SYMBOL_GPL(rcuhead_debug_descr); #endif /* #ifdef CONFIG_DEBUG_OBJECTS_RCU_HEAD */ + +#if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) || defined(CONFIG_RCU_TRACE) +void do_trace_rcu_torture_read(char *rcutorturename, struct rcu_head *rhp) +{ + trace_rcu_torture_read(rcutorturename, rhp); +} +EXPORT_SYMBOL_GPL(do_trace_rcu_torture_read); +#else +#define do_trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) +#endif diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 764825c2685c..df35228e743b 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -913,6 +913,18 @@ rcu_torture_fakewriter(void *arg) return 0; } +void rcutorture_trace_dump(void) +{ + static atomic_t beenhere = ATOMIC_INIT(0); + + if (atomic_read(&beenhere)) + return; + if (atomic_xchg(&beenhere, 1) != 0) + return; + do_trace_rcu_torture_read(cur_ops->name, (struct rcu_head *)~0UL); + ftrace_dump(DUMP_ALL); +} + /* * RCU torture reader from timer handler. Dereferences rcu_torture_current, * incrementing the corresponding element of the pipeline array. The @@ -934,6 +946,7 @@ static void rcu_torture_timer(unsigned long unused) rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || srcu_read_lock_held(&srcu_ctl)); + do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); if (p == NULL) { /* Leave because rcu_torture_writer is not yet underway */ cur_ops->readunlock(idx); @@ -951,6 +964,8 @@ static void rcu_torture_timer(unsigned long unused) /* Should not happen, but... */ pipe_count = RCU_TORTURE_PIPE_LEN; } + if (pipe_count > 1) + rcutorture_trace_dump(); __this_cpu_inc(rcu_torture_count[pipe_count]); completed = cur_ops->completed() - completed; if (completed > RCU_TORTURE_PIPE_LEN) { @@ -994,6 +1009,7 @@ rcu_torture_reader(void *arg) rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || srcu_read_lock_held(&srcu_ctl)); + do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu); if (p == NULL) { /* Wait for rcu_torture_writer to get underway */ cur_ops->readunlock(idx); @@ -1009,6 +1025,8 @@ rcu_torture_reader(void *arg) /* Should not happen, but... */ pipe_count = RCU_TORTURE_PIPE_LEN; } + if (pipe_count > 1) + rcutorture_trace_dump(); __this_cpu_inc(rcu_torture_count[pipe_count]); completed = cur_ops->completed() - completed; if (completed > RCU_TORTURE_PIPE_LEN) { |