[PATCH tip/core/rcu 03/40] rcu: Make rcutorture's batches-completed API use ->gp_seq
From: Paul E. McKenney
Date: Mon Jun 25 2018 - 20:14:49 EST
The rcutorture test invokes rcu_batches_started(),
rcu_batches_completed(), rcu_batches_started_bh(),
rcu_batches_completed_bh(), rcu_batches_started_sched(), and
rcu_batches_completed_sched() to do grace-period consistency checks,
and rcuperf uses the _completed variants for statistics.
These functions use ->gpnum and ->completed. This commit therefore
replaces them with rcu_get_gp_seq(), rcu_bh_get_gp_seq(), and
rcu_sched_get_gp_seq(), adjusting rcutorture and rcuperf to make
use of them.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/rcu.h | 18 +++++----------
kernel/rcu/rcuperf.c | 26 ++++++++-------------
kernel/rcu/rcutorture.c | 50 +++++++++++++++-------------------------
kernel/rcu/tree.c | 51 ++++++++++-------------------------------
4 files changed, 45 insertions(+), 100 deletions(-)
diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
index db0870acfdff..f0907f9f6cd0 100644
--- a/kernel/rcu/rcu.h
+++ b/kernel/rcu/rcu.h
@@ -463,12 +463,9 @@ void srcutorture_get_gp_data(enum rcutorture_type test_type,
#endif
#ifdef CONFIG_TINY_RCU
-static inline unsigned long rcu_batches_started(void) { return 0; }
-static inline unsigned long rcu_batches_started_bh(void) { return 0; }
-static inline unsigned long rcu_batches_started_sched(void) { return 0; }
-static inline unsigned long rcu_batches_completed(void) { return 0; }
-static inline unsigned long rcu_batches_completed_bh(void) { return 0; }
-static inline unsigned long rcu_batches_completed_sched(void) { return 0; }
+static inline unsigned long rcu_get_gp_seq(void) { return 0; }
+static inline unsigned long rcu_bh_get_gp_seq(void) { return 0; }
+static inline unsigned long rcu_sched_get_gp_seq(void) { return 0; }
static inline unsigned long rcu_exp_batches_completed(void) { return 0; }
static inline unsigned long rcu_exp_batches_completed_sched(void) { return 0; }
static inline unsigned long
@@ -480,12 +477,9 @@ static inline void show_rcu_gp_kthreads(void) { }
#else /* #ifdef CONFIG_TINY_RCU */
extern unsigned long rcutorture_testseq;
extern unsigned long rcutorture_vernum;
-unsigned long rcu_batches_started(void);
-unsigned long rcu_batches_started_bh(void);
-unsigned long rcu_batches_started_sched(void);
-unsigned long rcu_batches_completed(void);
-unsigned long rcu_batches_completed_bh(void);
-unsigned long rcu_batches_completed_sched(void);
+unsigned long rcu_get_gp_seq(void);
+unsigned long rcu_bh_get_gp_seq(void);
+unsigned long rcu_sched_get_gp_seq(void);
unsigned long rcu_exp_batches_completed(void);
unsigned long rcu_exp_batches_completed_sched(void);
unsigned long srcu_batches_completed(struct srcu_struct *sp);
diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index df29119b2013..2b5a613afcf3 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -138,8 +138,7 @@ struct rcu_perf_ops {
void (*cleanup)(void);
int (*readlock)(void);
void (*readunlock)(int idx);
- unsigned long (*started)(void);
- unsigned long (*completed)(void);
+ unsigned long (*get_gp_seq)(void);
unsigned long (*exp_completed)(void);
void (*async)(struct rcu_head *head, rcu_callback_t func);
void (*gp_barrier)(void);
@@ -179,8 +178,7 @@ static struct rcu_perf_ops rcu_ops = {
.init = rcu_sync_perf_init,
.readlock = rcu_perf_read_lock,
.readunlock = rcu_perf_read_unlock,
- .started = rcu_batches_started,
- .completed = rcu_batches_completed,
+ .get_gp_seq = rcu_get_gp_seq,
.exp_completed = rcu_exp_batches_completed,
.async = call_rcu,
.gp_barrier = rcu_barrier,
@@ -209,8 +207,7 @@ static struct rcu_perf_ops rcu_bh_ops = {
.init = rcu_sync_perf_init,
.readlock = rcu_bh_perf_read_lock,
.readunlock = rcu_bh_perf_read_unlock,
- .started = rcu_batches_started_bh,
- .completed = rcu_batches_completed_bh,
+ .get_gp_seq = rcu_bh_get_gp_seq,
.exp_completed = rcu_exp_batches_completed_sched,
.async = call_rcu_bh,
.gp_barrier = rcu_barrier_bh,
@@ -266,8 +263,7 @@ static struct rcu_perf_ops srcu_ops = {
.init = rcu_sync_perf_init,
.readlock = srcu_perf_read_lock,
.readunlock = srcu_perf_read_unlock,
- .started = NULL,
- .completed = srcu_perf_completed,
+ .get_gp_seq = srcu_perf_completed,
.exp_completed = srcu_perf_completed,
.async = srcu_call_rcu,
.gp_barrier = srcu_rcu_barrier,
@@ -295,8 +291,7 @@ static struct rcu_perf_ops srcud_ops = {
.cleanup = srcu_sync_perf_cleanup,
.readlock = srcu_perf_read_lock,
.readunlock = srcu_perf_read_unlock,
- .started = NULL,
- .completed = srcu_perf_completed,
+ .get_gp_seq = srcu_perf_completed,
.exp_completed = srcu_perf_completed,
.async = srcu_call_rcu,
.gp_barrier = srcu_rcu_barrier,
@@ -325,8 +320,7 @@ static struct rcu_perf_ops sched_ops = {
.init = rcu_sync_perf_init,
.readlock = sched_perf_read_lock,
.readunlock = sched_perf_read_unlock,
- .started = rcu_batches_started_sched,
- .completed = rcu_batches_completed_sched,
+ .get_gp_seq = rcu_sched_get_gp_seq,
.exp_completed = rcu_exp_batches_completed_sched,
.async = call_rcu_sched,
.gp_barrier = rcu_barrier_sched,
@@ -353,8 +347,7 @@ static struct rcu_perf_ops tasks_ops = {
.init = rcu_sync_perf_init,
.readlock = tasks_perf_read_lock,
.readunlock = tasks_perf_read_unlock,
- .started = rcu_no_completed,
- .completed = rcu_no_completed,
+ .get_gp_seq = rcu_no_completed,
.async = call_rcu_tasks,
.gp_barrier = rcu_barrier_tasks,
.sync = synchronize_rcu_tasks,
@@ -447,8 +440,7 @@ rcu_perf_writer(void *arg)
b_rcu_perf_writer_started =
cur_ops->exp_completed() / 2;
} else {
- b_rcu_perf_writer_started =
- cur_ops->completed();
+ b_rcu_perf_writer_started = cur_ops->get_gp_seq();
}
}
@@ -505,7 +497,7 @@ rcu_perf_writer(void *arg)
cur_ops->exp_completed() / 2;
} else {
b_rcu_perf_writer_finished =
- cur_ops->completed();
+ cur_ops->get_gp_seq();
}
if (shutdown) {
smp_mb(); /* Assign before wake. */
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 5604bfac8df4..1f66597c7783 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -264,8 +264,7 @@ struct rcu_torture_ops {
int (*readlock)(void);
void (*read_delay)(struct torture_random_state *rrsp);
void (*readunlock)(int idx);
- unsigned long (*started)(void);
- unsigned long (*completed)(void);
+ unsigned long (*get_gp_seq)(void);
void (*deferred_free)(struct rcu_torture *p);
void (*sync)(void);
void (*exp_sync)(void);
@@ -305,10 +304,10 @@ static void rcu_read_delay(struct torture_random_state *rrsp)
* force_quiescent_state. */
if (!(torture_random(rrsp) % (nrealreaders * 2000 * longdelay_ms))) {
- started = cur_ops->completed();
+ started = cur_ops->get_gp_seq();
ts = rcu_trace_clock_local();
mdelay(longdelay_ms);
- completed = cur_ops->completed();
+ completed = cur_ops->get_gp_seq();
do_trace_rcu_torture_read(cur_ops->name, NULL, ts,
started, completed);
}
@@ -400,8 +399,7 @@ static struct rcu_torture_ops rcu_ops = {
.readlock = rcu_torture_read_lock,
.read_delay = rcu_read_delay,
.readunlock = rcu_torture_read_unlock,
- .started = rcu_batches_started,
- .completed = rcu_batches_completed,
+ .get_gp_seq = rcu_get_gp_seq,
.deferred_free = rcu_torture_deferred_free,
.sync = synchronize_rcu,
.exp_sync = synchronize_rcu_expedited,
@@ -442,8 +440,7 @@ static struct rcu_torture_ops rcu_bh_ops = {
.readlock = rcu_bh_torture_read_lock,
.read_delay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = rcu_bh_torture_read_unlock,
- .started = rcu_batches_started_bh,
- .completed = rcu_batches_completed_bh,
+ .get_gp_seq = rcu_bh_get_gp_seq,
.deferred_free = rcu_bh_torture_deferred_free,
.sync = synchronize_rcu_bh,
.exp_sync = synchronize_rcu_bh_expedited,
@@ -486,8 +483,7 @@ static struct rcu_torture_ops rcu_busted_ops = {
.readlock = rcu_torture_read_lock,
.read_delay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = rcu_torture_read_unlock,
- .started = rcu_no_completed,
- .completed = rcu_no_completed,
+ .get_gp_seq = rcu_no_completed,
.deferred_free = rcu_busted_torture_deferred_free,
.sync = synchronize_rcu_busted,
.exp_sync = synchronize_rcu_busted,
@@ -575,8 +571,7 @@ static struct rcu_torture_ops srcu_ops = {
.readlock = srcu_torture_read_lock,
.read_delay = srcu_read_delay,
.readunlock = srcu_torture_read_unlock,
- .started = NULL,
- .completed = srcu_torture_completed,
+ .get_gp_seq = srcu_torture_completed,
.deferred_free = srcu_torture_deferred_free,
.sync = srcu_torture_synchronize,
.exp_sync = srcu_torture_synchronize_expedited,
@@ -613,8 +608,7 @@ static struct rcu_torture_ops srcud_ops = {
.readlock = srcu_torture_read_lock,
.read_delay = srcu_read_delay,
.readunlock = srcu_torture_read_unlock,
- .started = NULL,
- .completed = srcu_torture_completed,
+ .get_gp_seq = srcu_torture_completed,
.deferred_free = srcu_torture_deferred_free,
.sync = srcu_torture_synchronize,
.exp_sync = srcu_torture_synchronize_expedited,
@@ -651,8 +645,7 @@ static struct rcu_torture_ops sched_ops = {
.readlock = sched_torture_read_lock,
.read_delay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = sched_torture_read_unlock,
- .started = rcu_batches_started_sched,
- .completed = rcu_batches_completed_sched,
+ .get_gp_seq = rcu_sched_get_gp_seq,
.deferred_free = rcu_sched_torture_deferred_free,
.sync = synchronize_sched,
.exp_sync = synchronize_sched_expedited,
@@ -690,8 +683,7 @@ static struct rcu_torture_ops tasks_ops = {
.readlock = tasks_torture_read_lock,
.read_delay = rcu_read_delay, /* just reuse rcu's version. */
.readunlock = tasks_torture_read_unlock,
- .started = rcu_no_completed,
- .completed = rcu_no_completed,
+ .get_gp_seq = rcu_no_completed,
.deferred_free = rcu_tasks_torture_deferred_free,
.sync = synchronize_rcu_tasks,
.exp_sync = synchronize_rcu_tasks,
@@ -1104,10 +1096,7 @@ static void rcu_torture_timer(struct timer_list *unused)
unsigned long long ts;
idx = cur_ops->readlock();
- if (cur_ops->started)
- started = cur_ops->started();
- else
- started = cur_ops->completed();
+ started = cur_ops->get_gp_seq();
ts = rcu_trace_clock_local();
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
@@ -1131,7 +1120,7 @@ static void rcu_torture_timer(struct timer_list *unused)
/* Should not happen, but... */
pipe_count = RCU_TORTURE_PIPE_LEN;
}
- completed = cur_ops->completed();
+ completed = cur_ops->get_gp_seq();
if (pipe_count > 1) {
do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu, ts,
started, completed);
@@ -1139,8 +1128,8 @@ static void rcu_torture_timer(struct timer_list *unused)
}
__this_cpu_inc(rcu_torture_count[pipe_count]);
completed = completed - started;
- if (cur_ops->started)
- completed++;
+ if (completed > ULONG_MAX >> 1)
+ completed = 0; /* Not all gp_seq have full range. */
if (completed > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
completed = RCU_TORTURE_PIPE_LEN;
@@ -1187,10 +1176,7 @@ rcu_torture_reader(void *arg)
mod_timer(&t, jiffies + 1);
}
idx = cur_ops->readlock();
- if (cur_ops->started)
- started = cur_ops->started();
- else
- started = cur_ops->completed();
+ started = cur_ops->get_gp_seq();
ts = rcu_trace_clock_local();
p = rcu_dereference_check(rcu_torture_current,
rcu_read_lock_bh_held() ||
@@ -1212,7 +1198,7 @@ rcu_torture_reader(void *arg)
/* Should not happen, but... */
pipe_count = RCU_TORTURE_PIPE_LEN;
}
- completed = cur_ops->completed();
+ completed = cur_ops->get_gp_seq();
if (pipe_count > 1) {
do_trace_rcu_torture_read(cur_ops->name, &p->rtort_rcu,
ts, started, completed);
@@ -1220,8 +1206,8 @@ rcu_torture_reader(void *arg)
}
__this_cpu_inc(rcu_torture_count[pipe_count]);
completed = completed - started;
- if (cur_ops->started)
- completed++;
+ if (completed > ULONG_MAX >> 1)
+ completed = 0; /* Not all gp_seq have full range. */
if (completed > RCU_TORTURE_PIPE_LEN) {
/* Should not happen, but... */
completed = RCU_TORTURE_PIPE_LEN;
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 90346ffd721f..0961f6c61894 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -530,58 +530,31 @@ static void force_quiescent_state(struct rcu_state *rsp);
static int rcu_pending(void);
/*
- * Return the number of RCU batches started thus far for debug & stats.
+ * Return the number of RCU GPs completed thus far for debug & stats.
*/
-unsigned long rcu_batches_started(void)
+unsigned long rcu_get_gp_seq(void)
{
- return rcu_state_p->gpnum;
+ return rcu_seq_ctr(READ_ONCE(rcu_state_p->gp_seq));
}
-EXPORT_SYMBOL_GPL(rcu_batches_started);
+EXPORT_SYMBOL_GPL(rcu_get_gp_seq);
/*
- * Return the number of RCU-sched batches started thus far for debug & stats.
+ * Return the number of RCU-sched GPs completed thus far for debug & stats.
*/
-unsigned long rcu_batches_started_sched(void)
+unsigned long rcu_sched_get_gp_seq(void)
{
- return rcu_sched_state.gpnum;
+ return rcu_seq_ctr(READ_ONCE(rcu_sched_state.gp_seq));
}
-EXPORT_SYMBOL_GPL(rcu_batches_started_sched);
+EXPORT_SYMBOL_GPL(rcu_sched_get_gp_seq);
/*
- * Return the number of RCU BH batches started thus far for debug & stats.
+ * Return the number of RCU-bh GPs completed thus far for debug & stats.
*/
-unsigned long rcu_batches_started_bh(void)
+unsigned long rcu_bh_get_gp_seq(void)
{
- return rcu_bh_state.gpnum;
+ return rcu_seq_ctr(READ_ONCE(rcu_bh_state.gp_seq));
}
-EXPORT_SYMBOL_GPL(rcu_batches_started_bh);
-
-/*
- * Return the number of RCU batches completed thus far for debug & stats.
- */
-unsigned long rcu_batches_completed(void)
-{
- return rcu_state_p->completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed);
-
-/*
- * Return the number of RCU-sched batches completed thus far for debug & stats.
- */
-unsigned long rcu_batches_completed_sched(void)
-{
- return rcu_sched_state.completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed_sched);
-
-/*
- * Return the number of RCU BH batches completed thus far for debug & stats.
- */
-unsigned long rcu_batches_completed_bh(void)
-{
- return rcu_bh_state.completed;
-}
-EXPORT_SYMBOL_GPL(rcu_batches_completed_bh);
+EXPORT_SYMBOL_GPL(rcu_bh_get_gp_seq);
/*
* Return the number of RCU expedited batches completed thus far for
--
2.17.1