linux/include/trace/events/rcu.h
Steven Rostedt (Red Hat) e66c33d579 rcu: Add const annotation to char * for RCU tracepoints and functions
All the RCU tracepoints and functions that reference char pointers do
so with just 'char *' even though they do not modify the contents of
the string itself. This will cause warnings if a const char * is used
in one of these functions.

The RCU tracepoints store the pointer to the string to refer back to them
when the trace output is displayed. As this can be minutes, hours or
even days later, those strings had better be constant.

This change also opens the door to allow the RCU tracepoint strings and
their addresses to be exported so that userspace tracing tools can
translate the contents of the pointers of the RCU tracepoints.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2013-07-29 17:07:49 -04:00

686 lines
20 KiB
C

#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_TREE_PREEMPT_RCU)
/*
* Tracepoint for grace-period events: starting and ending a grace
* period ("start" and "end", respectively), a CPU noting the start
* of a new grace period or the end of an old grace period ("cpustart"
* and "cpuend", respectively), a CPU passing through a quiescent
* state ("cpuqs"), a CPU coming online or going offline ("cpuonl"
* and "cpuofl", respectively), a CPU being kicked for being too
* long in dyntick-idle mode ("kick"), a CPU accelerating its new
* callbacks to RCU_NEXT_READY_TAIL ("AccReadyCB"), and a CPU
* accelerating its new callbacks to RCU_WAIT_TAIL ("AccWaitCB").
*/
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 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_TREE_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,
bool cb, bool nr, bool iit, bool risk),
TP_ARGS(rcuname, callbacks_invoked, cb, nr, iit, risk),
TP_STRUCT__entry(
__field(const char *, rcuname)
__field(int, callbacks_invoked)
__field(bool, cb)
__field(bool, nr)
__field(bool, iit)
__field(bool, 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_callback() started.
* "Check": rcu_barrier_callback() checking for piggybacking.
* "EarlyExit": rcu_barrier_callback() piggybacked, thus early exit.
* "Inc1": rcu_barrier_callback() piggyback check counter incremented.
* "Offline": rcu_barrier_callback() found offline CPU
* "OnlineNoCB": rcu_barrier_callback() found online no-CBs CPU.
* "OnlineQ": rcu_barrier_callback() found online CPU with callbacks.
* "OnlineNQ": rcu_barrier_callback() 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_callback() 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_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>