Initial import

1 files changed, 740 insertions, 0 deletions

diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h
new file mode 100644
index 000000000..c78e88ce5
--- /dev/null
+++ b/include/trace/events/rcu.h
@@ -0,0 +1,740 @@
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM rcu
+
+#if !defined(_TRACE_RCU_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_RCU_H
+
+#include <linux/tracepoint.h>
+
+/*
+ * Tracepoint for start/end markers used for utilization calculations.
+ * By convention, the string is of the following forms:
+ *
+ * "Start <activity>" -- Mark the start of the specified activity,
+ *			 such as "context switch".  Nesting is permitted.
+ * "End <activity>" -- Mark the end of the specified activity.
+ *
+ * An "@" character within "<activity>" is a comment character: Data
+ * reduction scripts will ignore the "@" and the remainder of the line.
+ */
+TRACE_EVENT(rcu_utilization,
+
+	TP_PROTO(const char *s),
+
+	TP_ARGS(s),
+
+	TP_STRUCT__entry(
+		__field(const char *, s)
+	),
+
+	TP_fast_assign(
+		__entry->s = s;
+	),
+
+	TP_printk("%s", __entry->s)
+);
+
+#ifdef CONFIG_RCU_TRACE
+
+#if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
+
+/*
+ * Tracepoint for grace-period events.  Takes a string identifying the
+ * RCU flavor, the grace-period number, and a string identifying the
+ * grace-period-related event as follows:
+ *
+ *	"AccReadyCB": CPU acclerates new callbacks to RCU_NEXT_READY_TAIL.
+ *	"AccWaitCB": CPU accelerates new callbacks to RCU_WAIT_TAIL.
+ *	"newreq": Request a new grace period.
+ *	"start": Start a grace period.
+ *	"cpustart": CPU first notices a grace-period start.
+ *	"cpuqs": CPU passes through a quiescent state.
+ *	"cpuonl": CPU comes online.
+ *	"cpuofl": CPU goes offline.
+ *	"reqwait": GP kthread sleeps waiting for grace-period request.
+ *	"reqwaitsig": GP kthread awakened by signal from reqwait state.
+ *	"fqswait": GP kthread waiting until time to force quiescent states.
+ *	"fqsstart": GP kthread starts forcing quiescent states.
+ *	"fqsend": GP kthread done forcing quiescent states.
+ *	"fqswaitsig": GP kthread awakened by signal from fqswait state.
+ *	"end": End a grace period.
+ *	"cpuend": CPU first notices a grace-period end.
+ */
+TRACE_EVENT(rcu_grace_period,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum, const char *gpevent),
+
+	TP_ARGS(rcuname, gpnum, gpevent),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(const char *, gpevent)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->gpevent = gpevent;
+	),
+
+	TP_printk("%s %lu %s",
+		  __entry->rcuname, __entry->gpnum, __entry->gpevent)
+);
+
+/*
+ * Tracepoint for future grace-period events, including those for no-callbacks
+ * CPUs.  The caller should pull the data from the rcu_node structure,
+ * other than rcuname, which comes from the rcu_state structure, and event,
+ * which is one of the following:
+ *
+ * "Startleaf": Request a nocb grace period based on leaf-node data.
+ * "Startedleaf": Leaf-node start proved sufficient.
+ * "Startedleafroot": Leaf-node start proved sufficient after checking root.
+ * "Startedroot": Requested a nocb grace period based on root-node data.
+ * "StartWait": Start waiting for the requested grace period.
+ * "ResumeWait": Resume waiting after signal.
+ * "EndWait": Complete wait.
+ * "Cleanup": Clean up rcu_node structure after previous GP.
+ * "CleanupMore": Clean up, and another no-CB GP is needed.
+ */
+TRACE_EVENT(rcu_future_grace_period,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum, unsigned long completed,
+		 unsigned long c, u8 level, int grplo, int grphi,
+		 const char *gpevent),
+
+	TP_ARGS(rcuname, gpnum, completed, c, level, grplo, grphi, gpevent),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(unsigned long, completed)
+		__field(unsigned long, c)
+		__field(u8, level)
+		__field(int, grplo)
+		__field(int, grphi)
+		__field(const char *, gpevent)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->completed = completed;
+		__entry->c = c;
+		__entry->level = level;
+		__entry->grplo = grplo;
+		__entry->grphi = grphi;
+		__entry->gpevent = gpevent;
+	),
+
+	TP_printk("%s %lu %lu %lu %u %d %d %s",
+		  __entry->rcuname, __entry->gpnum, __entry->completed,
+		  __entry->c, __entry->level, __entry->grplo, __entry->grphi,
+		  __entry->gpevent)
+);
+
+/*
+ * Tracepoint for grace-period-initialization events.  These are
+ * distinguished by the type of RCU, the new grace-period number, the
+ * rcu_node structure level, the starting and ending CPU covered by the
+ * rcu_node structure, and the mask of CPUs that will be waited for.
+ * All but the type of RCU are extracted from the rcu_node structure.
+ */
+TRACE_EVENT(rcu_grace_period_init,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum, u8 level,
+		 int grplo, int grphi, unsigned long qsmask),
+
+	TP_ARGS(rcuname, gpnum, level, grplo, grphi, qsmask),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(u8, level)
+		__field(int, grplo)
+		__field(int, grphi)
+		__field(unsigned long, qsmask)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->level = level;
+		__entry->grplo = grplo;
+		__entry->grphi = grphi;
+		__entry->qsmask = qsmask;
+	),
+
+	TP_printk("%s %lu %u %d %d %lx",
+		  __entry->rcuname, __entry->gpnum, __entry->level,
+		  __entry->grplo, __entry->grphi, __entry->qsmask)
+);
+
+/*
+ * Tracepoint for RCU no-CBs CPU callback handoffs.  This event is intended
+ * to assist debugging of these handoffs.
+ *
+ * The first argument is the name of the RCU flavor, and the second is
+ * the number of the offloaded CPU are extracted.  The third and final
+ * argument is a string as follows:
+ *
+ *	"WakeEmpty": Wake rcuo kthread, first CB to empty list.
+ *	"WakeEmptyIsDeferred": Wake rcuo kthread later, first CB to empty list.
+ *	"WakeOvf": Wake rcuo kthread, CB list is huge.
+ *	"WakeOvfIsDeferred": Wake rcuo kthread later, CB list is huge.
+ *	"WakeNot": Don't wake rcuo kthread.
+ *	"WakeNotPoll": Don't wake rcuo kthread because it is polling.
+ *	"DeferredWake": Carried out the "IsDeferred" wakeup.
+ *	"Poll": Start of new polling cycle for rcu_nocb_poll.
+ *	"Sleep": Sleep waiting for CBs for !rcu_nocb_poll.
+ *	"WokeEmpty": rcuo kthread woke to find empty list.
+ *	"WokeNonEmpty": rcuo kthread woke to find non-empty list.
+ *	"WaitQueue": Enqueue partially done, timed wait for it to complete.
+ *	"WokeQueue": Partial enqueue now complete.
+ */
+TRACE_EVENT(rcu_nocb_wake,
+
+	TP_PROTO(const char *rcuname, int cpu, const char *reason),
+
+	TP_ARGS(rcuname, cpu, reason),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(int, cpu)
+		__field(const char *, reason)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->cpu = cpu;
+		__entry->reason = reason;
+	),
+
+	TP_printk("%s %d %s", __entry->rcuname, __entry->cpu, __entry->reason)
+);
+
+/*
+ * Tracepoint for tasks blocking within preemptible-RCU read-side
+ * critical sections.  Track the type of RCU (which one day might
+ * include SRCU), the grace-period number that the task is blocking
+ * (the current or the next), and the task's PID.
+ */
+TRACE_EVENT(rcu_preempt_task,
+
+	TP_PROTO(const char *rcuname, int pid, unsigned long gpnum),
+
+	TP_ARGS(rcuname, pid, gpnum),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(int, pid)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->pid = pid;
+	),
+
+	TP_printk("%s %lu %d",
+		  __entry->rcuname, __entry->gpnum, __entry->pid)
+);
+
+/*
+ * Tracepoint for tasks that blocked within a given preemptible-RCU
+ * read-side critical section exiting that critical section.  Track the
+ * type of RCU (which one day might include SRCU) and the task's PID.
+ */
+TRACE_EVENT(rcu_unlock_preempted_task,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum, int pid),
+
+	TP_ARGS(rcuname, gpnum, pid),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(int, pid)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->pid = pid;
+	),
+
+	TP_printk("%s %lu %d", __entry->rcuname, __entry->gpnum, __entry->pid)
+);
+
+/*
+ * Tracepoint for quiescent-state-reporting events.  These are
+ * distinguished by the type of RCU, the grace-period number, the
+ * mask of quiescent lower-level entities, the rcu_node structure level,
+ * the starting and ending CPU covered by the rcu_node structure, and
+ * whether there are any blocked tasks blocking the current grace period.
+ * All but the type of RCU are extracted from the rcu_node structure.
+ */
+TRACE_EVENT(rcu_quiescent_state_report,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum,
+		 unsigned long mask, unsigned long qsmask,
+		 u8 level, int grplo, int grphi, int gp_tasks),
+
+	TP_ARGS(rcuname, gpnum, mask, qsmask, level, grplo, grphi, gp_tasks),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(unsigned long, mask)
+		__field(unsigned long, qsmask)
+		__field(u8, level)
+		__field(int, grplo)
+		__field(int, grphi)
+		__field(u8, gp_tasks)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->mask = mask;
+		__entry->qsmask = qsmask;
+		__entry->level = level;
+		__entry->grplo = grplo;
+		__entry->grphi = grphi;
+		__entry->gp_tasks = gp_tasks;
+	),
+
+	TP_printk("%s %lu %lx>%lx %u %d %d %u",
+		  __entry->rcuname, __entry->gpnum,
+		  __entry->mask, __entry->qsmask, __entry->level,
+		  __entry->grplo, __entry->grphi, __entry->gp_tasks)
+);
+
+/*
+ * Tracepoint for quiescent states detected by force_quiescent_state().
+ * These trace events include the type of RCU, the grace-period number
+ * that was blocked by the CPU, the CPU itself, and the type of quiescent
+ * state, which can be "dti" for dyntick-idle mode, "ofl" for CPU offline,
+ * or "kick" when kicking a CPU that has been in dyntick-idle mode for
+ * too long.
+ */
+TRACE_EVENT(rcu_fqs,
+
+	TP_PROTO(const char *rcuname, unsigned long gpnum, int cpu, const char *qsevent),
+
+	TP_ARGS(rcuname, gpnum, cpu, qsevent),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(unsigned long, gpnum)
+		__field(int, cpu)
+		__field(const char *, qsevent)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->gpnum = gpnum;
+		__entry->cpu = cpu;
+		__entry->qsevent = qsevent;
+	),
+
+	TP_printk("%s %lu %d %s",
+		  __entry->rcuname, __entry->gpnum,
+		  __entry->cpu, __entry->qsevent)
+);
+
+#endif /* #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU) */
+
+/*
+ * Tracepoint for dyntick-idle entry/exit events.  These take a string
+ * as argument: "Start" for entering dyntick-idle mode, "End" for
+ * leaving it, "--=" for events moving towards idle, and "++=" for events
+ * moving away from idle.  "Error on entry: not idle task" and "Error on
+ * exit: not idle task" indicate that a non-idle task is erroneously
+ * toying with the idle loop.
+ *
+ * These events also take a pair of numbers, which indicate the nesting
+ * depth before and after the event of interest.  Note that task-related
+ * events use the upper bits of each number, while interrupt-related
+ * events use the lower bits.
+ */
+TRACE_EVENT(rcu_dyntick,
+
+	TP_PROTO(const char *polarity, long long oldnesting, long long newnesting),
+
+	TP_ARGS(polarity, oldnesting, newnesting),
+
+	TP_STRUCT__entry(
+		__field(const char *, polarity)
+		__field(long long, oldnesting)
+		__field(long long, newnesting)
+	),
+
+	TP_fast_assign(
+		__entry->polarity = polarity;
+		__entry->oldnesting = oldnesting;
+		__entry->newnesting = newnesting;
+	),
+
+	TP_printk("%s %llx %llx", __entry->polarity,
+		  __entry->oldnesting, __entry->newnesting)
+);
+
+/*
+ * Tracepoint for RCU preparation for idle, the goal being to get RCU
+ * processing done so that the current CPU can shut off its scheduling
+ * clock and enter dyntick-idle mode.  One way to accomplish this is
+ * to drain all RCU callbacks from this CPU, and the other is to have
+ * done everything RCU requires for the current grace period.  In this
+ * latter case, the CPU will be awakened at the end of the current grace
+ * period in order to process the remainder of its callbacks.
+ *
+ * These tracepoints take a string as argument:
+ *
+ *	"No callbacks": Nothing to do, no callbacks on this CPU.
+ *	"In holdoff": Nothing to do, holding off after unsuccessful attempt.
+ *	"Begin holdoff": Attempt failed, don't retry until next jiffy.
+ *	"Dyntick with callbacks": Entering dyntick-idle despite callbacks.
+ *	"Dyntick with lazy callbacks": Entering dyntick-idle w/lazy callbacks.
+ *	"More callbacks": Still more callbacks, try again to clear them out.
+ *	"Callbacks drained": All callbacks processed, off to dyntick idle!
+ *	"Timer": Timer fired to cause CPU to continue processing callbacks.
+ *	"Demigrate": Timer fired on wrong CPU, woke up correct CPU.
+ *	"Cleanup after idle": Idle exited, timer canceled.
+ */
+TRACE_EVENT(rcu_prep_idle,
+
+	TP_PROTO(const char *reason),
+
+	TP_ARGS(reason),
+
+	TP_STRUCT__entry(
+		__field(const char *, reason)
+	),
+
+	TP_fast_assign(
+		__entry->reason = reason;
+	),
+
+	TP_printk("%s", __entry->reason)
+);
+
+/*
+ * Tracepoint for the registration of a single RCU callback function.
+ * The first argument is the type of RCU, the second argument is
+ * a pointer to the RCU callback itself, the third element is the
+ * number of lazy callbacks queued, and the fourth element is the
+ * total number of callbacks queued.
+ */
+TRACE_EVENT(rcu_callback,
+
+	TP_PROTO(const char *rcuname, struct rcu_head *rhp, long qlen_lazy,
+		 long qlen),
+
+	TP_ARGS(rcuname, rhp, qlen_lazy, qlen),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(void *, rhp)
+		__field(void *, func)
+		__field(long, qlen_lazy)
+		__field(long, qlen)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->rhp = rhp;
+		__entry->func = rhp->func;
+		__entry->qlen_lazy = qlen_lazy;
+		__entry->qlen = qlen;
+	),
+
+	TP_printk("%s rhp=%p func=%pf %ld/%ld",
+		  __entry->rcuname, __entry->rhp, __entry->func,
+		  __entry->qlen_lazy, __entry->qlen)
+);
+
+/*
+ * Tracepoint for the registration of a single RCU callback of the special
+ * kfree() form.  The first argument is the RCU type, the second argument
+ * is a pointer to the RCU callback, the third argument is the offset
+ * of the callback within the enclosing RCU-protected data structure,
+ * the fourth argument is the number of lazy callbacks queued, and the
+ * fifth argument is the total number of callbacks queued.
+ */
+TRACE_EVENT(rcu_kfree_callback,
+
+	TP_PROTO(const char *rcuname, struct rcu_head *rhp, unsigned long offset,
+		 long qlen_lazy, long qlen),
+
+	TP_ARGS(rcuname, rhp, offset, qlen_lazy, qlen),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(void *, rhp)
+		__field(unsigned long, offset)
+		__field(long, qlen_lazy)
+		__field(long, qlen)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->rhp = rhp;
+		__entry->offset = offset;
+		__entry->qlen_lazy = qlen_lazy;
+		__entry->qlen = qlen;
+	),
+
+	TP_printk("%s rhp=%p func=%ld %ld/%ld",
+		  __entry->rcuname, __entry->rhp, __entry->offset,
+		  __entry->qlen_lazy, __entry->qlen)
+);
+
+/*
+ * Tracepoint for marking the beginning rcu_do_batch, performed to start
+ * RCU callback invocation.  The first argument is the RCU flavor,
+ * the second is the number of lazy callbacks queued, the third is
+ * the total number of callbacks queued, and the fourth argument is
+ * the current RCU-callback batch limit.
+ */
+TRACE_EVENT(rcu_batch_start,
+
+	TP_PROTO(const char *rcuname, long qlen_lazy, long qlen, long blimit),
+
+	TP_ARGS(rcuname, qlen_lazy, qlen, blimit),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(long, qlen_lazy)
+		__field(long, qlen)
+		__field(long, blimit)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->qlen_lazy = qlen_lazy;
+		__entry->qlen = qlen;
+		__entry->blimit = blimit;
+	),
+
+	TP_printk("%s CBs=%ld/%ld bl=%ld",
+		  __entry->rcuname, __entry->qlen_lazy, __entry->qlen,
+		  __entry->blimit)
+);
+
+/*
+ * Tracepoint for the invocation of a single RCU callback function.
+ * The first argument is the type of RCU, and the second argument is
+ * a pointer to the RCU callback itself.
+ */
+TRACE_EVENT(rcu_invoke_callback,
+
+	TP_PROTO(const char *rcuname, struct rcu_head *rhp),
+
+	TP_ARGS(rcuname, rhp),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(void *, rhp)
+		__field(void *, func)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->rhp = rhp;
+		__entry->func = rhp->func;
+	),
+
+	TP_printk("%s rhp=%p func=%pf",
+		  __entry->rcuname, __entry->rhp, __entry->func)
+);
+
+/*
+ * Tracepoint for the invocation of a single RCU callback of the special
+ * kfree() form.  The first argument is the RCU flavor, the second
+ * argument is a pointer to the RCU callback, and the third argument
+ * is the offset of the callback within the enclosing RCU-protected
+ * data structure.
+ */
+TRACE_EVENT(rcu_invoke_kfree_callback,
+
+	TP_PROTO(const char *rcuname, struct rcu_head *rhp, unsigned long offset),
+
+	TP_ARGS(rcuname, rhp, offset),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(void *, rhp)
+		__field(unsigned long, offset)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->rhp = rhp;
+		__entry->offset	= offset;
+	),
+
+	TP_printk("%s rhp=%p func=%ld",
+		  __entry->rcuname, __entry->rhp, __entry->offset)
+);
+
+/*
+ * Tracepoint for exiting rcu_do_batch after RCU callbacks have been
+ * invoked.  The first argument is the name of the RCU flavor,
+ * the second argument is number of callbacks actually invoked,
+ * the third argument (cb) is whether or not any of the callbacks that
+ * were ready to invoke at the beginning of this batch are still
+ * queued, the fourth argument (nr) is the return value of need_resched(),
+ * the fifth argument (iit) is 1 if the current task is the idle task,
+ * and the sixth argument (risk) is the return value from
+ * rcu_is_callbacks_kthread().
+ */
+TRACE_EVENT(rcu_batch_end,
+
+	TP_PROTO(const char *rcuname, int callbacks_invoked,
+		 char cb, char nr, char iit, char risk),
+
+	TP_ARGS(rcuname, callbacks_invoked, cb, nr, iit, risk),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(int, callbacks_invoked)
+		__field(char, cb)
+		__field(char, nr)
+		__field(char, iit)
+		__field(char, risk)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->callbacks_invoked = callbacks_invoked;
+		__entry->cb = cb;
+		__entry->nr = nr;
+		__entry->iit = iit;
+		__entry->risk = risk;
+	),
+
+	TP_printk("%s CBs-invoked=%d idle=%c%c%c%c",
+		  __entry->rcuname, __entry->callbacks_invoked,
+		  __entry->cb ? 'C' : '.',
+		  __entry->nr ? 'S' : '.',
+		  __entry->iit ? 'I' : '.',
+		  __entry->risk ? 'R' : '.')
+);
+
+/*
+ * 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(const char *rcutorturename, struct rcu_head *rhp,
+		 unsigned long secs, unsigned long c_old, unsigned long c),
+
+	TP_ARGS(rcutorturename, rhp, secs, c_old, c),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcutorturename)
+		__field(struct rcu_head *, rhp)
+		__field(unsigned long, secs)
+		__field(unsigned long, c_old)
+		__field(unsigned long, c)
+	),
+
+	TP_fast_assign(
+		__entry->rcutorturename = rcutorturename;
+		__entry->rhp = rhp;
+		__entry->secs = secs;
+		__entry->c_old = c_old;
+		__entry->c = c;
+	),
+
+	TP_printk("%s torture read %p %luus c: %lu %lu",
+		  __entry->rcutorturename, __entry->rhp,
+		  __entry->secs, __entry->c_old, __entry->c)
+);
+
+/*
+ * Tracepoint for _rcu_barrier() execution.  The string "s" describes
+ * the _rcu_barrier phase:
+ *	"Begin": _rcu_barrier() started.
+ *	"Check": _rcu_barrier() checking for piggybacking.
+ *	"EarlyExit": _rcu_barrier() piggybacked, thus early exit.
+ *	"Inc1": _rcu_barrier() piggyback check counter incremented.
+ *	"OfflineNoCB": _rcu_barrier() found callback on never-online CPU
+ *	"OnlineNoCB": _rcu_barrier() found online no-CBs CPU.
+ *	"OnlineQ": _rcu_barrier() found online CPU with callbacks.
+ *	"OnlineNQ": _rcu_barrier() found online CPU, no callbacks.
+ *	"IRQ": An rcu_barrier_callback() callback posted on remote CPU.
+ *	"CB": An rcu_barrier_callback() invoked a callback, not the last.
+ *	"LastCB": An rcu_barrier_callback() invoked the last callback.
+ *	"Inc2": _rcu_barrier() piggyback check counter incremented.
+ * The "cpu" argument is the CPU or -1 if meaningless, the "cnt" argument
+ * is the count of remaining callbacks, and "done" is the piggybacking count.
+ */
+TRACE_EVENT(rcu_barrier,
+
+	TP_PROTO(const char *rcuname, const char *s, int cpu, int cnt, unsigned long done),
+
+	TP_ARGS(rcuname, s, cpu, cnt, done),
+
+	TP_STRUCT__entry(
+		__field(const char *, rcuname)
+		__field(const char *, s)
+		__field(int, cpu)
+		__field(int, cnt)
+		__field(unsigned long, done)
+	),
+
+	TP_fast_assign(
+		__entry->rcuname = rcuname;
+		__entry->s = s;
+		__entry->cpu = cpu;
+		__entry->cnt = cnt;
+		__entry->done = done;
+	),
+
+	TP_printk("%s %s cpu %d remaining %d # %lu",
+		  __entry->rcuname, __entry->s, __entry->cpu, __entry->cnt,
+		  __entry->done)
+);
+
+#else /* #ifdef CONFIG_RCU_TRACE */
+
+#define trace_rcu_grace_period(rcuname, gpnum, gpevent) do { } while (0)
+#define trace_rcu_grace_period_init(rcuname, gpnum, level, grplo, grphi, \
+				    qsmask) do { } while (0)
+#define trace_rcu_future_grace_period(rcuname, gpnum, completed, c, \
+				      level, grplo, grphi, event) \
+				      do { } while (0)
+#define trace_rcu_nocb_wake(rcuname, cpu, reason) do { } while (0)
+#define trace_rcu_preempt_task(rcuname, pid, gpnum) do { } while (0)
+#define trace_rcu_unlock_preempted_task(rcuname, gpnum, pid) do { } while (0)
+#define trace_rcu_quiescent_state_report(rcuname, gpnum, mask, qsmask, level, \
+					 grplo, grphi, gp_tasks) do { } \
+	while (0)
+#define trace_rcu_fqs(rcuname, gpnum, cpu, qsevent) do { } while (0)
+#define trace_rcu_dyntick(polarity, oldnesting, newnesting) do { } while (0)
+#define trace_rcu_prep_idle(reason) do { } while (0)
+#define trace_rcu_callback(rcuname, rhp, qlen_lazy, qlen) do { } while (0)
+#define trace_rcu_kfree_callback(rcuname, rhp, offset, qlen_lazy, qlen) \
+	do { } while (0)
+#define trace_rcu_batch_start(rcuname, qlen_lazy, qlen, blimit) \
+	do { } while (0)
+#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, cb, nr, iit, risk) \
+	do { } while (0)
+#define trace_rcu_torture_read(rcutorturename, rhp, secs, c_old, c) \
+	do { } while (0)
+#define trace_rcu_barrier(name, s, cpu, cnt, done) do { } while (0)
+
+#endif /* #else #ifdef CONFIG_RCU_TRACE */
+
+#endif /* _TRACE_RCU_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>