diff options
| -rw-r--r-- | include/linux/rcupdate.h | 8 | ||||
| -rw-r--r-- | include/trace/events/rcu.h | 26 | ||||
| -rw-r--r-- | kernel/rcupdate.c | 10 | ||||
| -rw-r--r-- | kernel/rcutorture.c | 18 |
4 files changed, 62 insertions, 0 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index cd1ad4b04c6..8d315b013e3 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -51,6 +51,8 @@ extern int rcutorture_runnable; /* for sysctl */ #if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) extern void rcutorture_record_test_transition(void); extern void rcutorture_record_progress(unsigned long vernum); +extern void do_trace_rcu_torture_read(char *rcutorturename, + struct rcu_head *rhp); #else static inline void rcutorture_record_test_transition(void) { @@ -58,6 +60,12 @@ static inline void rcutorture_record_test_transition(void) static inline void rcutorture_record_progress(unsigned long vernum) { } +#ifdef CONFIG_RCU_TRACE +extern void do_trace_rcu_torture_read(char *rcutorturename, + struct rcu_head *rhp); +#else +#define do_trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) +#endif #endif #define UINT_CMP_GE(a, b) (UINT_MAX / 2 >= (a) - (b)) diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index e5771804c50..172620a92b1 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -437,6 +437,31 @@ TRACE_EVENT(rcu_batch_end, __entry->rcuname, __entry->callbacks_invoked) ); +/* + * Tracepoint for rcutorture readers. The first argument is the name + * of the RCU flavor from rcutorture's viewpoint and the second argument + * is the callback address. + */ +TRACE_EVENT(rcu_torture_read, + + TP_PROTO(char *rcutorturename, struct rcu_head *rhp), + + TP_ARGS(rcutorturename, rhp), + + TP_STRUCT__entry( + __field(char *, rcutorturename) + __field(struct rcu_head *, rhp) + ), + + TP_fast_assign( + __entry->rcutorturename = rcutorturename; + __entry->rhp = rhp; + ), + + TP_printk("%s torture read %p", + __entry->rcutorturename, __entry->rhp) +); + #else /* #ifdef CONFIG_RCU_TRACE */ #define trace_rcu_grace_period(rcuname, gpnum, gpevent) do { } while (0) @@ -452,6 +477,7 @@ TRACE_EVENT(rcu_batch_end, #define trace_rcu_invoke_callback(rcuname, rhp) do { } while (0) #define trace_rcu_invoke_kfree_callback(rcuname, rhp, offset) do { } while (0) #define trace_rcu_batch_end(rcuname, callbacks_invoked) do { } while (0) +#define trace_rcu_torture_read(rcutorturename, rhp) do { } while (0) #endif /* #else #ifdef CONFIG_RCU_TRACE */ diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index c5b98e565ae..92e771d7b44 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 764825c2685..df35228e743 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) { |