[PATCH tip/core/rcu 11/12] rcu: Rename rcu_data's ->deferred_qs to ->exp_deferred_qs

From: Paul E. McKenney
Date: Thu May 30 2019 - 10:57:04 EST


The rcu_data structure's ->deferred_qs field is used to indicate that the
current CPU is blocking an expedited grace period (perhaps a future one).
Given that it is used only for expedited grace periods, its current name
is misleading, so this commit renames it to ->exp_deferred_qs.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
---
kernel/rcu/tree.h | 2 +-
kernel/rcu/tree_exp.h | 8 ++++----
kernel/rcu/tree_plugin.h | 14 +++++++-------
3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 21d740f0b8dc..7acaf3a62d39 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -154,7 +154,7 @@ struct rcu_data {
bool core_needs_qs; /* Core waits for quiesc state. */
bool beenonline; /* CPU online at least once. */
bool gpwrap; /* Possible ->gp_seq wrap. */
- bool deferred_qs; /* This CPU awaiting a deferred QS? */
+ bool exp_deferred_qs; /* This CPU awaiting a deferred QS? */
struct rcu_node *mynode; /* This CPU's leaf of hierarchy */
unsigned long grpmask; /* Mask to apply to leaf qsmask. */
unsigned long ticks_this_gp; /* The number of scheduling-clock */
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index de1b4acf6979..e0c928d04be5 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -250,7 +250,7 @@ static void rcu_report_exp_cpu_mult(struct rcu_node *rnp,
*/
static void rcu_report_exp_rdp(struct rcu_data *rdp)
{
- WRITE_ONCE(rdp->deferred_qs, false);
+ WRITE_ONCE(rdp->exp_deferred_qs, false);
rcu_report_exp_cpu_mult(rdp->mynode, rdp->grpmask, true);
}

@@ -616,7 +616,7 @@ static void rcu_exp_handler(void *unused)
rcu_dynticks_curr_cpu_in_eqs()) {
rcu_report_exp_rdp(rdp);
} else {
- rdp->deferred_qs = true;
+ rdp->exp_deferred_qs = true;
set_tsk_need_resched(t);
set_preempt_need_resched();
}
@@ -638,7 +638,7 @@ static void rcu_exp_handler(void *unused)
if (t->rcu_read_lock_nesting > 0) {
raw_spin_lock_irqsave_rcu_node(rnp, flags);
if (rnp->expmask & rdp->grpmask) {
- rdp->deferred_qs = true;
+ rdp->exp_deferred_qs = true;
t->rcu_read_unlock_special.b.exp_hint = true;
}
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
@@ -661,7 +661,7 @@ static void rcu_exp_handler(void *unused)
*
* Otherwise, force a context switch after the CPU enables everything.
*/
- rdp->deferred_qs = true;
+ rdp->exp_deferred_qs = true;
if (!(preempt_count() & (PREEMPT_MASK | SOFTIRQ_MASK)) ||
WARN_ON_ONCE(rcu_dynticks_curr_cpu_in_eqs())) {
rcu_preempt_deferred_qs(t);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 58c7853f19e7..1aeb4ae187ce 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -237,10 +237,10 @@ static void rcu_preempt_ctxt_queue(struct rcu_node *rnp, struct rcu_data *rdp)
* no need to check for a subsequent expedited GP. (Though we are
* still in a quiescent state in any case.)
*/
- if (blkd_state & RCU_EXP_BLKD && rdp->deferred_qs)
+ if (blkd_state & RCU_EXP_BLKD && rdp->exp_deferred_qs)
rcu_report_exp_rdp(rdp);
else
- WARN_ON_ONCE(rdp->deferred_qs);
+ WARN_ON_ONCE(rdp->exp_deferred_qs);
}

/*
@@ -337,7 +337,7 @@ void rcu_note_context_switch(bool preempt)
* means that we continue to block the current grace period.
*/
rcu_qs();
- if (rdp->deferred_qs)
+ if (rdp->exp_deferred_qs)
rcu_report_exp_rdp(rdp);
trace_rcu_utilization(TPS("End context switch"));
barrier(); /* Avoid RCU read-side critical sections leaking up. */
@@ -451,7 +451,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
*/
special = t->rcu_read_unlock_special;
rdp = this_cpu_ptr(&rcu_data);
- if (!special.s && !rdp->deferred_qs) {
+ if (!special.s && !rdp->exp_deferred_qs) {
local_irq_restore(flags);
return;
}
@@ -459,7 +459,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
if (special.b.need_qs) {
rcu_qs();
t->rcu_read_unlock_special.b.need_qs = false;
- if (!t->rcu_read_unlock_special.s && !rdp->deferred_qs) {
+ if (!t->rcu_read_unlock_special.s && !rdp->exp_deferred_qs) {
local_irq_restore(flags);
return;
}
@@ -471,7 +471,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
* tasks are handled when removing the task from the
* blocked-tasks list below.
*/
- if (rdp->deferred_qs) {
+ if (rdp->exp_deferred_qs) {
rcu_report_exp_rdp(rdp);
if (!t->rcu_read_unlock_special.s) {
local_irq_restore(flags);
@@ -560,7 +560,7 @@ rcu_preempt_deferred_qs_irqrestore(struct task_struct *t, unsigned long flags)
*/
static bool rcu_preempt_need_deferred_qs(struct task_struct *t)
{
- return (__this_cpu_read(rcu_data.deferred_qs) ||
+ return (__this_cpu_read(rcu_data.exp_deferred_qs) ||
READ_ONCE(t->rcu_read_unlock_special.s)) &&
t->rcu_read_lock_nesting <= 0;
}
--
2.17.1