Commit d4c08f2a authored by Paul E. McKenney's avatar Paul E. McKenney Committed by Paul E. McKenney

rcu: Add grace-period, quiescent-state, and call_rcu trace events

Add trace events to record grace-period start and end, quiescent states,
CPUs noticing grace-period start and end, grace-period initialization,
call_rcu() invocation, tasks blocking in RCU read-side critical sections,
tasks exiting those same critical sections, force_quiescent_state()
detection of dyntick-idle and offline CPUs, CPUs entering and leaving
dyntick-idle mode (except from NMIs), CPUs coming online and going
offline, and CPUs being kicked for staying in dyntick-idle mode for too
long (as in many weeks, even on 32-bit systems).
Signed-off-by: default avatarPaul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>

rcu: Add the rcu flavor to callback trace events

The earlier trace events for registering RCU callbacks and for invoking
them did not include the RCU flavor (rcu_bh, rcu_preempt, or rcu_sched).
This commit adds the RCU flavor to those trace events.
Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
parent 965a002b
...@@ -34,6 +34,297 @@ TRACE_EVENT(rcu_utilization, ...@@ -34,6 +34,297 @@ TRACE_EVENT(rcu_utilization,
TP_printk("%s", __entry->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), and a CPU being kicked for being too
* long in dyntick-idle mode ("kick").
*/
TRACE_EVENT(rcu_grace_period,
TP_PROTO(char *rcuname, unsigned long gpnum, char *gpevent),
TP_ARGS(rcuname, gpnum, gpevent),
TP_STRUCT__entry(
__field(char *, rcuname)
__field(unsigned long, gpnum)
__field(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 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(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(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(char *rcuname, int pid, unsigned long gpnum),
TP_ARGS(rcuname, pid, gpnum),
TP_STRUCT__entry(
__field(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(char *rcuname, unsigned long gpnum, int pid),
TP_ARGS(rcuname, gpnum, pid),
TP_STRUCT__entry(
__field(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(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(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(char *rcuname, unsigned long gpnum, int cpu, char *qsevent),
TP_ARGS(rcuname, gpnum, cpu, qsevent),
TP_STRUCT__entry(
__field(char *, rcuname)
__field(unsigned long, gpnum)
__field(int, cpu)
__field(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 and "End" for
* leaving it.
*/
TRACE_EVENT(rcu_dyntick,
TP_PROTO(char *polarity),
TP_ARGS(polarity),
TP_STRUCT__entry(
__field(char *, polarity)
),
TP_fast_assign(
__entry->polarity = polarity;
),
TP_printk("%s", __entry->polarity)
);
/*
* 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, and the third element is the
* new RCU callback queue length for the current CPU.
*/
TRACE_EVENT(rcu_callback,
TP_PROTO(char *rcuname, struct rcu_head *rhp, long qlen),
TP_ARGS(rcuname, rhp, qlen),
TP_STRUCT__entry(
__field(char *, rcuname)
__field(void *, rhp)
__field(void *, func)
__field(long, qlen)
),
TP_fast_assign(
__entry->rcuname = rcuname;
__entry->rhp = rhp;
__entry->func = rhp->func;
__entry->qlen = qlen;
),
TP_printk("%s rhp=%p func=%pf %ld",
__entry->rcuname, __entry->rhp, __entry->func, __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,
* and the fourth argument is the new RCU callback queue length for the
* current CPU.
*/
TRACE_EVENT(rcu_kfree_callback,
TP_PROTO(char *rcuname, struct rcu_head *rhp, unsigned long offset,
long qlen),
TP_ARGS(rcuname, rhp, offset, qlen),
TP_STRUCT__entry(
__field(char *, rcuname)
__field(void *, rhp)
__field(unsigned long, offset)
__field(long, qlen)
),
TP_fast_assign(
__entry->rcuname = rcuname;
__entry->rhp = rhp;
__entry->offset = offset;
__entry->qlen = qlen;
),
TP_printk("%s rhp=%p func=%ld %ld",
__entry->rcuname, __entry->rhp, __entry->offset,
__entry->qlen)
);
/* /*
* Tracepoint for marking the beginning rcu_do_batch, performed to start * Tracepoint for marking the beginning rcu_do_batch, performed to start
* RCU callback invocation. The first argument is the RCU flavor, * RCU callback invocation. The first argument is the RCU flavor,
...@@ -65,50 +356,58 @@ TRACE_EVENT(rcu_batch_start, ...@@ -65,50 +356,58 @@ TRACE_EVENT(rcu_batch_start,
/* /*
* Tracepoint for the invocation of a single RCU callback function. * Tracepoint for the invocation of a single RCU callback function.
* The argument is a pointer to the RCU callback itself. * 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, TRACE_EVENT(rcu_invoke_callback,
TP_PROTO(struct rcu_head *rhp), TP_PROTO(char *rcuname, struct rcu_head *rhp),
TP_ARGS(rhp), TP_ARGS(rcuname, rhp),
TP_STRUCT__entry( TP_STRUCT__entry(
__field(char *, rcuname)
__field(void *, rhp) __field(void *, rhp)
__field(void *, func) __field(void *, func)
), ),
TP_fast_assign( TP_fast_assign(
__entry->rcuname = rcuname;
__entry->rhp = rhp; __entry->rhp = rhp;
__entry->func = rhp->func; __entry->func = rhp->func;
), ),
TP_printk("rhp=%p func=%pf", __entry->rhp, __entry->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 * Tracepoint for the invocation of a single RCU callback of the special
* kfree() form. The first argument is a pointer to the RCU callback * kfree() form. The first argument is the RCU flavor, the second
* and the second argument is the offset of the callback within the * argument is a pointer to the RCU callback, and the third argument
* enclosing RCU-protected data structure. * is the offset of the callback within the enclosing RCU-protected
* data structure.
*/ */
TRACE_EVENT(rcu_invoke_kfree_callback, TRACE_EVENT(rcu_invoke_kfree_callback,
TP_PROTO(struct rcu_head *rhp, unsigned long offset), TP_PROTO(char *rcuname, struct rcu_head *rhp, unsigned long offset),
TP_ARGS(rhp, offset), TP_ARGS(rcuname, rhp, offset),
TP_STRUCT__entry( TP_STRUCT__entry(
__field(char *, rcuname)
__field(void *, rhp) __field(void *, rhp)
__field(unsigned long, offset) __field(unsigned long, offset)
), ),
TP_fast_assign( TP_fast_assign(
__entry->rcuname = rcuname;
__entry->rhp = rhp; __entry->rhp = rhp;
__entry->offset = offset; __entry->offset = offset;
), ),
TP_printk("rhp=%p func=%ld", __entry->rhp, __entry->offset) TP_printk("%s rhp=%p func=%ld",
__entry->rcuname, __entry->rhp, __entry->offset)
); );
/* /*
...@@ -136,6 +435,24 @@ TRACE_EVENT(rcu_batch_end, ...@@ -136,6 +435,24 @@ TRACE_EVENT(rcu_batch_end,
__entry->rcuname, __entry->callbacks_invoked) __entry->rcuname, __entry->callbacks_invoked)
); );
#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_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) do { } while (0)
#define trace_rcu_callback(rcuname, rhp, qlen) do { } while (0)
#define trace_rcu_kfree_callback(rcuname, rhp, offset, qlen) do { } while (0)
#define trace_rcu_batch_start(rcuname, 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) do { } while (0)
#endif /* #else #ifdef CONFIG_RCU_TRACE */
#endif /* _TRACE_RCU_H */ #endif /* _TRACE_RCU_H */
/* This part must be outside protection */ /* This part must be outside protection */
......
...@@ -69,15 +69,15 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head) ...@@ -69,15 +69,15 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head)
extern void kfree(const void *); extern void kfree(const void *);
static inline void __rcu_reclaim(struct rcu_head *head) static inline void __rcu_reclaim(char *rn, struct rcu_head *head)
{ {
unsigned long offset = (unsigned long)head->func; unsigned long offset = (unsigned long)head->func;
if (__is_kfree_rcu_offset(offset)) { if (__is_kfree_rcu_offset(offset)) {
RCU_TRACE(trace_rcu_invoke_kfree_callback(head, offset)); RCU_TRACE(trace_rcu_invoke_kfree_callback(rn, head, offset));
kfree((void *)head - offset); kfree((void *)head - offset);
} else { } else {
RCU_TRACE(trace_rcu_invoke_callback(head)); RCU_TRACE(trace_rcu_invoke_callback(rn, head));
head->func(head); head->func(head);
} }
} }
......
...@@ -147,6 +147,7 @@ void rcu_check_callbacks(int cpu, int user) ...@@ -147,6 +147,7 @@ void rcu_check_callbacks(int cpu, int user)
*/ */
static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
{ {
char *rn = NULL;
struct rcu_head *next, *list; struct rcu_head *next, *list;
unsigned long flags; unsigned long flags;
RCU_TRACE(int cb_count = 0); RCU_TRACE(int cb_count = 0);
...@@ -171,12 +172,13 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp) ...@@ -171,12 +172,13 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
local_irq_restore(flags); local_irq_restore(flags);
/* Invoke the callbacks on the local list. */ /* Invoke the callbacks on the local list. */
RCU_TRACE(rn = rcp->name);
while (list) { while (list) {
next = list->next; next = list->next;
prefetch(next); prefetch(next);
debug_rcu_head_unqueue(list); debug_rcu_head_unqueue(list);
local_bh_disable(); local_bh_disable();
__rcu_reclaim(list); __rcu_reclaim(rn, list);
local_bh_enable(); local_bh_enable();
list = next; list = next;
RCU_TRACE(cb_count++); RCU_TRACE(cb_count++);
......
...@@ -166,6 +166,8 @@ void rcu_sched_qs(int cpu) ...@@ -166,6 +166,8 @@ void rcu_sched_qs(int cpu)
rdp->passed_quiesc_completed = rdp->gpnum - 1; rdp->passed_quiesc_completed = rdp->gpnum - 1;
barrier(); barrier();
if (rdp->passed_quiesc == 0)
trace_rcu_grace_period("rcu_sched", rdp->gpnum, "cpuqs");
rdp->passed_quiesc = 1; rdp->passed_quiesc = 1;
} }
...@@ -175,6 +177,8 @@ void rcu_bh_qs(int cpu) ...@@ -175,6 +177,8 @@ void rcu_bh_qs(int cpu)
rdp->passed_quiesc_completed = rdp->gpnum - 1; rdp->passed_quiesc_completed = rdp->gpnum - 1;
barrier(); barrier();
if (rdp->passed_quiesc == 0)
trace_rcu_grace_period("rcu_bh", rdp->gpnum, "cpuqs");
rdp->passed_quiesc = 1; rdp->passed_quiesc = 1;
} }
...@@ -319,6 +323,7 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp) ...@@ -319,6 +323,7 @@ static int rcu_implicit_offline_qs(struct rcu_data *rdp)
* trust its state not to change because interrupts are disabled. * trust its state not to change because interrupts are disabled.
*/ */
if (cpu_is_offline(rdp->cpu)) { if (cpu_is_offline(rdp->cpu)) {
trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, "ofl");
rdp->offline_fqs++; rdp->offline_fqs++;
return 1; return 1;
} }
...@@ -359,6 +364,7 @@ void rcu_enter_nohz(void) ...@@ -359,6 +364,7 @@ void rcu_enter_nohz(void)
local_irq_restore(flags); local_irq_restore(flags);
return; return;
} }
trace_rcu_dyntick("Start");
/* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */ /* CPUs seeing atomic_inc() must see prior RCU read-side crit sects */
smp_mb__before_atomic_inc(); /* See above. */ smp_mb__before_atomic_inc(); /* See above. */
atomic_inc(&rdtp->dynticks); atomic_inc(&rdtp->dynticks);
...@@ -396,6 +402,7 @@ void rcu_exit_nohz(void) ...@@ -396,6 +402,7 @@ void rcu_exit_nohz(void)
/* CPUs seeing atomic_inc() must see later RCU read-side crit sects */ /* CPUs seeing atomic_inc() must see later RCU read-side crit sects */
smp_mb__after_atomic_inc(); /* See above. */ smp_mb__after_atomic_inc(); /* See above. */
WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1)); WARN_ON_ONCE(!(atomic_read(&rdtp->dynticks) & 0x1));
trace_rcu_dyntick("End");
local_irq_restore(flags); local_irq_restore(flags);
} }
...@@ -501,6 +508,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp) ...@@ -501,6 +508,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
* of the current RCU grace period. * of the current RCU grace period.
*/ */
if ((curr & 0x1) == 0 || ULONG_CMP_GE(curr, snap + 2)) { if ((curr & 0x1) == 0 || ULONG_CMP_GE(curr, snap + 2)) {
trace_rcu_fqs(rdp->rsp->name, rdp->gpnum, rdp->cpu, "dti");
rdp->dynticks_fqs++; rdp->dynticks_fqs++;
return 1; return 1;
} }
...@@ -683,6 +691,7 @@ static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct ...@@ -683,6 +691,7 @@ static void __note_new_gpnum(struct rcu_state *rsp, struct rcu_node *rnp, struct
* go looking for one. * go looking for one.
*/ */
rdp->gpnum = rnp->gpnum; rdp->gpnum = rnp->gpnum;
trace_rcu_grace_period(rsp->name, rdp->gpnum, "cpustart");
if (rnp->qsmask & rdp->grpmask) { if (rnp->qsmask & rdp->grpmask) {
rdp->qs_pending = 1; rdp->qs_pending = 1;
rdp->passed_quiesc = 0; rdp->passed_quiesc = 0;
...@@ -746,6 +755,7 @@ __rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_dat ...@@ -746,6 +755,7 @@ __rcu_process_gp_end(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_dat
/* Remember that we saw this grace-period completion. */ /* Remember that we saw this grace-period completion. */
rdp->completed = rnp->completed; rdp->completed = rnp->completed;
trace_rcu_grace_period(rsp->name, rdp->gpnum, "cpuend");
/* /*
* If we were in an extended quiescent state, we may have * If we were in an extended quiescent state, we may have
...@@ -856,6 +866,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) ...@@ -856,6 +866,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/* Advance to a new grace period and initialize state. */ /* Advance to a new grace period and initialize state. */
rsp->gpnum++; rsp->gpnum++;
trace_rcu_grace_period(rsp->name, rsp->gpnum, "start");
WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT); WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT);
rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */ rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */
rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS; rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS;
...@@ -870,6 +881,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) ...@@ -870,6 +881,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */ rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
rcu_start_gp_per_cpu(rsp, rnp, rdp); rcu_start_gp_per_cpu(rsp, rnp, rdp);
rcu_preempt_boost_start_gp(rnp); rcu_preempt_boost_start_gp(rnp);
trace_rcu_grace_period_init(rsp->name, rnp->gpnum,
rnp->level, rnp->grplo,
rnp->grphi, rnp->qsmask);
raw_spin_unlock_irqrestore(&rnp->lock, flags); raw_spin_unlock_irqrestore(&rnp->lock, flags);
return; return;
} }
...@@ -906,6 +920,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags) ...@@ -906,6 +920,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
if (rnp == rdp->mynode) if (rnp == rdp->mynode)
rcu_start_gp_per_cpu(rsp, rnp, rdp); rcu_start_gp_per_cpu(rsp, rnp, rdp);
rcu_preempt_boost_start_gp(rnp); rcu_preempt_boost_start_gp(rnp);
trace_rcu_grace_period_init(rsp->name, rnp->gpnum,
rnp->level, rnp->grplo,
rnp->grphi, rnp->qsmask);
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
} }
...@@ -939,6 +956,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags) ...@@ -939,6 +956,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
if (gp_duration > rsp->gp_max) if (gp_duration > rsp->gp_max)
rsp->gp_max = gp_duration; rsp->gp_max = gp_duration;
rsp->completed = rsp->gpnum; rsp->completed = rsp->gpnum;
trace_rcu_grace_period(rsp->name, rsp->completed, "end");
rsp->signaled = RCU_GP_IDLE; rsp->signaled = RCU_GP_IDLE;
rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */ rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */
} }
...@@ -967,6 +985,10 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp, ...@@ -967,6 +985,10 @@ rcu_report_qs_rnp(unsigned long mask, struct rcu_state *rsp,
return; return;
} }
rnp->qsmask &= ~mask; rnp->qsmask &= ~mask;
trace_rcu_quiescent_state_report(rsp->name, rnp->gpnum,
mask, rnp->qsmask, rnp->level,
rnp->grplo, rnp->grphi,
!!rnp->gp_tasks);
if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) { if (rnp->qsmask != 0 || rcu_preempt_blocked_readers_cgp(rnp)) {
/* Other bits still set at this level, so done. */ /* Other bits still set at this level, so done. */
...@@ -1135,11 +1157,20 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp) ...@@ -1135,11 +1157,20 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
if (rnp->qsmaskinit != 0) { if (rnp->qsmaskinit != 0) {
if (rnp != rdp->mynode) if (rnp != rdp->mynode)
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
else
trace_rcu_grace_period(rsp->name,
rnp->gpnum + 1 -
!!(rnp->qsmask & mask),
"cpuofl");
break; break;
} }
if (rnp == rdp->mynode) if (rnp == rdp->mynode) {
trace_rcu_grace_period(rsp->name,
rnp->gpnum + 1 -
!!(rnp->qsmask & mask),
"cpuofl");
need_report = rcu_preempt_offline_tasks(rsp, rnp, rdp); need_report = rcu_preempt_offline_tasks(rsp, rnp, rdp);
else } else
raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */
mask = rnp->grpmask; mask = rnp->grpmask;
rnp = rnp->parent; rnp = rnp->parent;
...@@ -1226,7 +1257,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) ...@@ -1226,7 +1257,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp)
next = list->next; next = list->next;
prefetch(next); prefetch(next);
debug_rcu_head_unqueue(list); debug_rcu_head_unqueue(list);
__rcu_reclaim(list); __rcu_reclaim(rsp->name, list);
list = next; list = next;
if (++count >= bl) if (++count >= bl)
break; break;
...@@ -1552,6 +1583,12 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), ...@@ -1552,6 +1583,12 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
rdp->nxttail[RCU_NEXT_TAIL] = &head->next; rdp->nxttail[RCU_NEXT_TAIL] = &head->next;
rdp->qlen++; rdp->qlen++;
if (__is_kfree_rcu_offset((unsigned long)func))
trace_rcu_kfree_callback(rsp->name, head, (unsigned long)func,
rdp->qlen);
else
trace_rcu_callback(rsp->name, head, rdp->qlen);
/* If interrupts were disabled, don't dive into RCU core. */ /* If interrupts were disabled, don't dive into RCU core. */
if (irqs_disabled_flags(flags)) { if (irqs_disabled_flags(flags)) {
local_irq_restore(flags); local_irq_restore(flags);
...@@ -1850,6 +1887,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp) ...@@ -1850,6 +1887,7 @@ rcu_boot_init_percpu_data(int cpu, struct rcu_state *rsp)
rdp->dynticks = &per_cpu(rcu_dynticks, cpu); rdp->dynticks = &per_cpu(rcu_dynticks, cpu);
#endif /* #ifdef CONFIG_NO_HZ */ #endif /* #ifdef CONFIG_NO_HZ */
rdp->cpu = cpu; rdp->cpu = cpu;
rdp->rsp = rsp;
raw_spin_unlock_irqrestore(&rnp->lock, flags); raw_spin_unlock_irqrestore(&rnp->lock, flags);
} }
...@@ -1898,6 +1936,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible) ...@@ -1898,6 +1936,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptible)
rdp->gpnum = rnp->completed; /* if GP in progress... */ rdp->gpnum = rnp->completed; /* if GP in progress... */
rdp->completed = rnp->completed; rdp->completed = rnp->completed;
rdp->passed_quiesc_completed = rnp->completed - 1; rdp->passed_quiesc_completed = rnp->completed - 1;
trace_rcu_grace_period(rsp->name, rdp->gpnum, "cpuonl");
} }
raw_spin_unlock(&rnp->lock); /* irqs already disabled. */ raw_spin_unlock(&rnp->lock); /* irqs already disabled. */
rnp = rnp->parent; rnp = rnp->parent;
......
...@@ -299,6 +299,7 @@ struct rcu_data { ...@@ -299,6 +299,7 @@ struct rcu_data {
unsigned long n_rp_need_nothing; unsigned long n_rp_need_nothing;
int cpu; int cpu;
struct rcu_state *rsp;
}; };
/* Values for signaled field in struct rcu_state. */ /* Values for signaled field in struct rcu_state. */
......
...@@ -124,6 +124,8 @@ static void rcu_preempt_qs(int cpu) ...@@ -124,6 +124,8 @@ static void rcu_preempt_qs(int cpu)
rdp->passed_quiesc_completed = rdp->gpnum - 1; rdp->passed_quiesc_completed = rdp->gpnum - 1;
barrier(); barrier();
if (rdp->passed_quiesc == 0)
trace_rcu_grace_period("rcu_preempt", rdp->gpnum, "cpuqs");
rdp->passed_quiesc = 1; rdp->passed_quiesc = 1;
current->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS; current->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
} }
...@@ -190,6 +192,11 @@ static void rcu_preempt_note_context_switch(int cpu) ...@@ -190,6 +192,11 @@ static void rcu_preempt_note_context_switch(int cpu)
if (rnp->qsmask & rdp->grpmask) if (rnp->qsmask & rdp->grpmask)
rnp->gp_tasks = &t->rcu_node_entry; rnp->gp_tasks = &t->rcu_node_entry;
} }
trace_rcu_preempt_task(rdp->rsp->name,
t->pid,
(rnp->qsmask & rdp->grpmask)
? rnp->gpnum
: rnp->gpnum + 1);
raw_spin_unlock_irqrestore(&rnp->lock, flags); raw_spin_unlock_irqrestore(&rnp->lock, flags);
} else if (t->rcu_read_lock_nesting < 0 && } else if (t->rcu_read_lock_nesting < 0 &&
t->rcu_read_unlock_special) { t->rcu_read_unlock_special) {
...@@ -344,6 +351,8 @@ static noinline void rcu_read_unlock_special(struct task_struct *t) ...@@ -344,6 +351,8 @@ static noinline void rcu_read_unlock_special(struct task_struct *t)
smp_mb(); /* ensure expedited fastpath sees end of RCU c-s. */ smp_mb(); /* ensure expedited fastpath sees end of RCU c-s. */
np = rcu_next_node_entry(t, rnp); np = rcu_next_node_entry(t, rnp);
list_del_init(&t->rcu_node_entry); list_del_init(&t->rcu_node_entry);
trace_rcu_unlock_preempted_task("rcu_preempt",
rnp->gpnum, t->pid);
if (&t->rcu_node_entry == rnp->gp_tasks) if (&t->rcu_node_entry == rnp->gp_tasks)
rnp->gp_tasks = np; rnp->gp_tasks = np;
if (&t->rcu_node_entry == rnp->exp_tasks) if (&t->rcu_node_entry == rnp->exp_tasks)
...@@ -364,10 +373,17 @@ static noinline void rcu_read_unlock_special(struct task_struct *t) ...@@ -364,10 +373,17 @@ static noinline void rcu_read_unlock_special(struct task_struct *t)
* we aren't waiting on any CPUs, report the quiescent state. * we aren't waiting on any CPUs, report the quiescent state.
* Note that rcu_report_unblock_qs_rnp() releases rnp->lock. * Note that rcu_report_unblock_qs_rnp() releases rnp->lock.
*/ */
if (empty) if (!empty && !rcu_preempt_blocked_readers_cgp(rnp)) {
raw_spin_unlock_irqrestore(&rnp->lock, flags); trace_rcu_quiescent_state_report("preempt_rcu",
else rnp->gpnum,
0, rnp->qsmask,
rnp->level,
rnp->grplo,
rnp->grphi,
!!rnp->gp_tasks);
rcu_report_unblock_qs_rnp(rnp, flags); rcu_report_unblock_qs_rnp(rnp, flags);
} else
raw_spin_unlock_irqrestore(&rnp->lock, flags);
#ifdef CONFIG_RCU_BOOST #ifdef CONFIG_RCU_BOOST
/* Unboost if we were boosted. */ /* Unboost if we were boosted. */
......
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