[PATCH tip/core/rcu 41/52] rcu: Remove rcu_data structure's ->rsp field
From: Paul E. McKenney
Date: Wed Aug 29 2018 - 18:40:07 EST
Now that there is only one rcu_state structure, there is no need for the
rcu_data structure to indicate which it corresponds to. This commit
therefore removes the rcu_data structure's ->rsp field, replacing all
remaining uses of it with &rcu_state.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 28 +++++++++++++--------------
kernel/rcu/tree.h | 1 -
kernel/rcu/tree_plugin.h | 42 ++++++++++++++++++++--------------------
3 files changed, 34 insertions(+), 37 deletions(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 35b705c1da40..bc52f8c16faf 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1069,7 +1069,7 @@ static int dyntick_save_progress_counter(struct rcu_data *rdp)
{
rdp->dynticks_snap = rcu_dynticks_snap(rdp->dynticks);
if (rcu_dynticks_in_eqs(rdp->dynticks_snap)) {
- trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("dti"));
+ trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("dti"));
rcu_gpnum_ovf(rdp->mynode, rdp);
return 1;
}
@@ -1119,7 +1119,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
* of the current RCU grace period.
*/
if (rcu_dynticks_in_eqs_since(rdp->dynticks, rdp->dynticks_snap)) {
- trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("dti"));
+ trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("dti"));
rdp->dynticks_fqs++;
rcu_gpnum_ovf(rnp, rdp);
return 1;
@@ -1133,20 +1133,20 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
*/
jtsq = jiffies_till_sched_qs;
ruqp = per_cpu_ptr(&rcu_dynticks.rcu_urgent_qs, rdp->cpu);
- if (time_after(jiffies, rdp->rsp->gp_start + jtsq) &&
+ if (time_after(jiffies, rcu_state.gp_start + jtsq) &&
READ_ONCE(rdp->rcu_qs_ctr_snap) != per_cpu(rcu_dynticks.rcu_qs_ctr, rdp->cpu) &&
rcu_seq_current(&rdp->gp_seq) == rnp->gp_seq && !rdp->gpwrap) {
- trace_rcu_fqs(rdp->rsp->name, rdp->gp_seq, rdp->cpu, TPS("rqc"));
+ trace_rcu_fqs(rcu_state.name, rdp->gp_seq, rdp->cpu, TPS("rqc"));
rcu_gpnum_ovf(rnp, rdp);
return 1;
- } else if (time_after(jiffies, rdp->rsp->gp_start + jtsq)) {
+ } else if (time_after(jiffies, rcu_state.gp_start + jtsq)) {
/* Load rcu_qs_ctr before store to rcu_urgent_qs. */
smp_store_release(ruqp, true);
}
/* If waiting too long on an offline CPU, complain. */
if (!(rdp->grpmask & rcu_rnp_online_cpus(rnp)) &&
- time_after(jiffies, rdp->rsp->gp_start + HZ)) {
+ time_after(jiffies, rcu_state.gp_start + HZ)) {
bool onl;
struct rcu_node *rnp1;
@@ -1184,12 +1184,12 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
*/
rnhqp = &per_cpu(rcu_dynticks.rcu_need_heavy_qs, rdp->cpu);
if (!READ_ONCE(*rnhqp) &&
- (time_after(jiffies, rdp->rsp->gp_start + jtsq) ||
- time_after(jiffies, rdp->rsp->jiffies_resched))) {
+ (time_after(jiffies, rcu_state.gp_start + jtsq) ||
+ time_after(jiffies, rcu_state.jiffies_resched))) {
WRITE_ONCE(*rnhqp, true);
/* Store rcu_need_heavy_qs before rcu_urgent_qs. */
smp_store_release(ruqp, true);
- rdp->rsp->jiffies_resched += jtsq; /* Re-enable beating. */
+ rcu_state.jiffies_resched += jtsq; /* Re-enable beating. */
}
/*
@@ -1198,7 +1198,7 @@ static int rcu_implicit_dynticks_qs(struct rcu_data *rdp)
* see if the CPU is getting hammered with interrupts, but only
* once per grace period, just to keep the IPIs down to a dull roar.
*/
- if (jiffies - rdp->rsp->gp_start > rcu_jiffies_till_stall_check() / 2) {
+ if (jiffies - rcu_state.gp_start > rcu_jiffies_till_stall_check() / 2) {
resched_cpu(rdp->cpu);
if (IS_ENABLED(CONFIG_IRQ_WORK) &&
!rdp->rcu_iw_pending && rdp->rcu_iw_gp_seq != rnp->gp_seq &&
@@ -1525,7 +1525,7 @@ void rcu_cpu_stall_reset(void)
static void trace_rcu_this_gp(struct rcu_node *rnp, struct rcu_data *rdp,
unsigned long gp_seq_req, const char *s)
{
- trace_rcu_future_grace_period(rdp->rsp->name, rnp->gp_seq, gp_seq_req,
+ trace_rcu_future_grace_period(rcu_state.name, rnp->gp_seq, gp_seq_req,
rnp->level, rnp->grplo, rnp->grphi, s);
}
@@ -1549,7 +1549,7 @@ static bool rcu_start_this_gp(struct rcu_node *rnp_start, struct rcu_data *rdp,
unsigned long gp_seq_req)
{
bool ret = false;
- struct rcu_state *rsp = rdp->rsp;
+ struct rcu_state *rsp = &rcu_state;
struct rcu_node *rnp;
/*
@@ -3166,8 +3166,7 @@ static void _rcu_barrier_trace(const char *s, int cpu, unsigned long done)
*/
static void rcu_barrier_callback(struct rcu_head *rhp)
{
- struct rcu_data *rdp = container_of(rhp, struct rcu_data, barrier_head);
- struct rcu_state *rsp = rdp->rsp;
+ struct rcu_state *rsp = &rcu_state;
if (atomic_dec_and_test(&rsp->barrier_cpu_count)) {
_rcu_barrier_trace(TPS("LastCB"), -1, rsp->barrier_sequence);
@@ -3364,7 +3363,6 @@ rcu_boot_init_percpu_data(int cpu)
rdp->rcu_onl_gp_seq = rcu_state.gp_seq;
rdp->rcu_onl_gp_flags = RCU_GP_CLEANED;
rdp->cpu = cpu;
- rdp->rsp = &rcu_state;
rcu_boot_init_nocb_percpu_data(rdp);
}
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index b21d79bdab23..6f1b1a3fc23d 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -265,7 +265,6 @@ struct rcu_data {
short rcu_onl_gp_flags; /* ->gp_flags at last online. */
int cpu;
- struct rcu_state *rsp;
};
/* Values for nocb_defer_wakeup field in struct rcu_data. */
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index b60d3df92ff5..5423f9e58494 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -350,7 +350,7 @@ void rcu_note_context_switch(bool preempt)
*/
WARN_ON_ONCE((rdp->grpmask & rcu_rnp_online_cpus(rnp)) == 0);
WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
- trace_rcu_preempt_task(rdp->rsp->name,
+ trace_rcu_preempt_task(rcu_state.name,
t->pid,
(rnp->qsmask & rdp->grpmask)
? rnp->gp_seq
@@ -1951,7 +1951,7 @@ static void wake_nocb_leader_defer(struct rcu_data *rdp, int waketype,
if (rdp->nocb_defer_wakeup == RCU_NOCB_WAKE_NOT)
mod_timer(&rdp->nocb_timer, jiffies + 1);
WRITE_ONCE(rdp->nocb_defer_wakeup, waketype);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, reason);
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, reason);
raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags);
}
@@ -2030,7 +2030,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
/* If we are not being polled and there is a kthread, awaken it ... */
t = READ_ONCE(rdp->nocb_kthread);
if (rcu_nocb_poll || !t) {
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("WakeNotPoll"));
return;
}
@@ -2039,7 +2039,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
if (!irqs_disabled_flags(flags)) {
/* ... if queue was empty ... */
wake_nocb_leader(rdp, false);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("WakeEmpty"));
} else {
wake_nocb_leader_defer(rdp, RCU_NOCB_WAKE,
@@ -2050,7 +2050,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
/* ... or if many callbacks queued. */
if (!irqs_disabled_flags(flags)) {
wake_nocb_leader(rdp, true);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("WakeOvf"));
} else {
wake_nocb_leader_defer(rdp, RCU_NOCB_WAKE_FORCE,
@@ -2058,7 +2058,7 @@ static void __call_rcu_nocb_enqueue(struct rcu_data *rdp,
}
rdp->qlen_last_fqs_check = LONG_MAX / 2;
} else {
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WakeNot"));
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WakeNot"));
}
return;
}
@@ -2080,12 +2080,12 @@ static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
return false;
__call_rcu_nocb_enqueue(rdp, rhp, &rhp->next, 1, lazy, flags);
if (__is_kfree_rcu_offset((unsigned long)rhp->func))
- trace_rcu_kfree_callback(rdp->rsp->name, rhp,
+ trace_rcu_kfree_callback(rcu_state.name, rhp,
(unsigned long)rhp->func,
-atomic_long_read(&rdp->nocb_q_count_lazy),
-atomic_long_read(&rdp->nocb_q_count));
else
- trace_rcu_callback(rdp->rsp->name, rhp,
+ trace_rcu_callback(rcu_state.name, rhp,
-atomic_long_read(&rdp->nocb_q_count_lazy),
-atomic_long_read(&rdp->nocb_q_count));
@@ -2135,7 +2135,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp)
struct rcu_node *rnp = rdp->mynode;
local_irq_save(flags);
- c = rcu_seq_snap(&rdp->rsp->gp_seq);
+ c = rcu_seq_snap(&rcu_state.gp_seq);
if (!rdp->gpwrap && ULONG_CMP_GE(rdp->gp_seq_needed, c)) {
local_irq_restore(flags);
} else {
@@ -2180,7 +2180,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
/* Wait for callbacks to appear. */
if (!rcu_nocb_poll) {
- trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Sleep"));
+ trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu, TPS("Sleep"));
swait_event_interruptible_exclusive(my_rdp->nocb_wq,
!READ_ONCE(my_rdp->nocb_leader_sleep));
raw_spin_lock_irqsave(&my_rdp->nocb_lock, flags);
@@ -2190,7 +2190,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
raw_spin_unlock_irqrestore(&my_rdp->nocb_lock, flags);
} else if (firsttime) {
firsttime = false; /* Don't drown trace log with "Poll"! */
- trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, TPS("Poll"));
+ trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu, TPS("Poll"));
}
/*
@@ -2217,7 +2217,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
if (rcu_nocb_poll) {
schedule_timeout_interruptible(1);
} else {
- trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, my_rdp->cpu,
TPS("WokeEmpty"));
}
goto wait_again;
@@ -2262,7 +2262,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
static void nocb_follower_wait(struct rcu_data *rdp)
{
for (;;) {
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("FollowerSleep"));
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("FollowerSleep"));
swait_event_interruptible_exclusive(rdp->nocb_wq,
READ_ONCE(rdp->nocb_follower_head));
if (smp_load_acquire(&rdp->nocb_follower_head)) {
@@ -2270,7 +2270,7 @@ static void nocb_follower_wait(struct rcu_data *rdp)
return;
}
WARN_ON(signal_pending(current));
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeEmpty"));
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeEmpty"));
}
}
@@ -2305,10 +2305,10 @@ static int rcu_nocb_kthread(void *arg)
rdp->nocb_follower_tail = &rdp->nocb_follower_head;
raw_spin_unlock_irqrestore(&rdp->nocb_lock, flags);
BUG_ON(!list);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("WokeNonEmpty"));
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("WokeNonEmpty"));
/* Each pass through the following loop invokes a callback. */
- trace_rcu_batch_start(rdp->rsp->name,
+ trace_rcu_batch_start(rcu_state.name,
atomic_long_read(&rdp->nocb_q_count_lazy),
atomic_long_read(&rdp->nocb_q_count), -1);
c = cl = 0;
@@ -2316,23 +2316,23 @@ static int rcu_nocb_kthread(void *arg)
next = list->next;
/* Wait for enqueuing to complete, if needed. */
while (next == NULL && &list->next != tail) {
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("WaitQueue"));
schedule_timeout_interruptible(1);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu,
TPS("WokeQueue"));
next = list->next;
}
debug_rcu_head_unqueue(list);
local_bh_disable();
- if (__rcu_reclaim(rdp->rsp->name, list))
+ if (__rcu_reclaim(rcu_state.name, list))
cl++;
c++;
local_bh_enable();
cond_resched_tasks_rcu_qs();
list = next;
}
- trace_rcu_batch_end(rdp->rsp->name, c, !!list, 0, 0, 1);
+ trace_rcu_batch_end(rcu_state.name, c, !!list, 0, 0, 1);
smp_mb__before_atomic(); /* _add after CB invocation. */
atomic_long_add(-c, &rdp->nocb_q_count);
atomic_long_add(-cl, &rdp->nocb_q_count_lazy);
@@ -2360,7 +2360,7 @@ static void do_nocb_deferred_wakeup_common(struct rcu_data *rdp)
ndw = READ_ONCE(rdp->nocb_defer_wakeup);
WRITE_ONCE(rdp->nocb_defer_wakeup, RCU_NOCB_WAKE_NOT);
__wake_nocb_leader(rdp, ndw == RCU_NOCB_WAKE_FORCE, flags);
- trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, TPS("DeferredWake"));
+ trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("DeferredWake"));
}
/* Do a deferred wakeup of rcu_nocb_kthread() from a timer handler. */
--
2.17.1