[PATCH tip/core/rcu 05/52] rcu: Remove rsp parameter from rcu_gp_in_progress()

From: Paul E. McKenney
Date: Wed Aug 29 2018 - 18:43:42 EST


There now is only one rcu_state structure in a given build of the
Linux kernel, so there is no need to pass it as a parameter to RCU's
functions. This commit therefore removes the rsp parameter from
rcu_gp_in_progress().

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 30 +++++++++++++++---------------
kernel/rcu/tree_plugin.h | 2 +-
2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 8977e37fcba3..605e1c990619 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -189,9 +189,9 @@ unsigned long rcu_rnp_online_cpus(struct rcu_node *rnp)
* permit this function to be invoked without holding the root rcu_node
* structure's ->lock, but of course results can be subject to change.
*/
-static int rcu_gp_in_progress(struct rcu_state *rsp)
+static int rcu_gp_in_progress(void)
{
- return rcu_seq_state(rcu_seq_current(&rsp->gp_seq));
+ return rcu_seq_state(rcu_seq_current(&rcu_state.gp_seq));
}

void rcu_softirq_qs(void)
@@ -1296,7 +1296,7 @@ static void rcu_stall_kick_kthreads(struct rcu_state *rsp)
return;
j = READ_ONCE(rsp->jiffies_kick_kthreads);
if (time_after(jiffies, j) && rsp->gp_kthread &&
- (rcu_gp_in_progress(rsp) || READ_ONCE(rsp->gp_flags))) {
+ (rcu_gp_in_progress() || READ_ONCE(rsp->gp_flags))) {
WARN_ONCE(1, "Kicking %s grace-period kthread\n", rsp->name);
rcu_ftrace_dump(DUMP_ALL);
wake_up_process(rsp->gp_kthread);
@@ -1448,7 +1448,7 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
struct rcu_node *rnp;

if ((rcu_cpu_stall_suppress && !rcu_kick_kthreads) ||
- !rcu_gp_in_progress(rsp))
+ !rcu_gp_in_progress())
return;
rcu_stall_kick_kthreads(rsp);
j = jiffies;
@@ -1483,14 +1483,14 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
return; /* No stall or GP completed since entering function. */
rnp = rdp->mynode;
jn = jiffies + 3 * rcu_jiffies_till_stall_check() + 3;
- if (rcu_gp_in_progress(rsp) &&
+ if (rcu_gp_in_progress() &&
(READ_ONCE(rnp->qsmask) & rdp->grpmask) &&
cmpxchg(&rsp->jiffies_stall, js, jn) == js) {

/* We haven't checked in, so go dump stack. */
print_cpu_stall(rsp);

- } else if (rcu_gp_in_progress(rsp) &&
+ } else if (rcu_gp_in_progress() &&
ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY) &&
cmpxchg(&rsp->jiffies_stall, js, jn) == js) {

@@ -1588,7 +1588,7 @@ static bool rcu_start_this_gp(struct rcu_node *rnp_start, struct rcu_data *rdp,
}

/* If GP already in progress, just leave, otherwise start one. */
- if (rcu_gp_in_progress(rsp)) {
+ if (rcu_gp_in_progress()) {
trace_rcu_this_gp(rnp, rdp, gp_seq_req, TPS("Startedleafroot"));
goto unlock_out;
}
@@ -1845,7 +1845,7 @@ static bool rcu_gp_init(struct rcu_state *rsp)
}
WRITE_ONCE(rsp->gp_flags, 0); /* Clear all flags: New grace period. */

- if (WARN_ON_ONCE(rcu_gp_in_progress(rsp))) {
+ if (WARN_ON_ONCE(rcu_gp_in_progress())) {
/*
* Grace period already in progress, don't start another.
* Not supposed to be able to happen.
@@ -2194,7 +2194,7 @@ static void rcu_report_qs_rsp(unsigned long flags)
struct rcu_state *rsp = &rcu_state;

raw_lockdep_assert_held_rcu_node(rcu_get_root(rsp));
- WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
+ WARN_ON_ONCE(!rcu_gp_in_progress());
WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
raw_spin_unlock_irqrestore_rcu_node(rcu_get_root(rsp), flags);
rcu_gp_kthread_wake(rsp);
@@ -2681,7 +2681,7 @@ rcu_check_gp_start_stall(struct rcu_state *rsp, struct rcu_node *rnp,
struct rcu_node *rnp_root = rcu_get_root(rsp);
static atomic_t warned = ATOMIC_INIT(0);

- if (!IS_ENABLED(CONFIG_PROVE_RCU) || rcu_gp_in_progress(rsp) ||
+ if (!IS_ENABLED(CONFIG_PROVE_RCU) || rcu_gp_in_progress() ||
ULONG_CMP_GE(rnp_root->gp_seq, rnp_root->gp_seq_needed))
return;
j = jiffies; /* Expensive access, and in common case don't get here. */
@@ -2692,7 +2692,7 @@ rcu_check_gp_start_stall(struct rcu_state *rsp, struct rcu_node *rnp,

raw_spin_lock_irqsave_rcu_node(rnp, flags);
j = jiffies;
- if (rcu_gp_in_progress(rsp) ||
+ if (rcu_gp_in_progress() ||
ULONG_CMP_GE(rnp_root->gp_seq, rnp_root->gp_seq_needed) ||
time_before(j, READ_ONCE(rsp->gp_req_activity) + gpssdelay) ||
time_before(j, READ_ONCE(rsp->gp_activity) + gpssdelay) ||
@@ -2705,7 +2705,7 @@ rcu_check_gp_start_stall(struct rcu_state *rsp, struct rcu_node *rnp,
if (rnp_root != rnp)
raw_spin_lock_rcu_node(rnp_root); /* irqs already disabled. */
j = jiffies;
- if (rcu_gp_in_progress(rsp) ||
+ if (rcu_gp_in_progress() ||
ULONG_CMP_GE(rnp_root->gp_seq, rnp_root->gp_seq_needed) ||
time_before(j, rsp->gp_req_activity + gpssdelay) ||
time_before(j, rsp->gp_activity + gpssdelay) ||
@@ -2750,7 +2750,7 @@ __rcu_process_callbacks(struct rcu_state *rsp)
rcu_check_quiescent_state(rsp, rdp);

/* No grace period and unregistered callbacks? */
- if (!rcu_gp_in_progress(rsp) &&
+ if (!rcu_gp_in_progress() &&
rcu_segcblist_is_enabled(&rdp->cblist)) {
local_irq_save(flags);
if (!rcu_segcblist_restempty(&rdp->cblist, RCU_NEXT_READY_TAIL))
@@ -2840,7 +2840,7 @@ static void __call_rcu_core(struct rcu_state *rsp, struct rcu_data *rdp,
note_gp_changes(rsp, rdp);

/* Start a new grace period if one not already started. */
- if (!rcu_gp_in_progress(rsp)) {
+ if (!rcu_gp_in_progress()) {
rcu_accelerate_cbs_unlocked(rsp, rdp->mynode, rdp);
} else {
/* Give the grace period a kick. */
@@ -3104,7 +3104,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
return 1;

/* Has RCU gone idle with this CPU needing another grace period? */
- if (!rcu_gp_in_progress(rsp) &&
+ if (!rcu_gp_in_progress() &&
rcu_segcblist_is_enabled(&rdp->cblist) &&
!rcu_segcblist_restempty(&rdp->cblist, RCU_NEXT_READY_TAIL))
return 1;
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 566828ecaecb..99f517035a6e 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2655,7 +2655,7 @@ static bool rcu_nohz_full_cpu(struct rcu_state *rsp)
{
#ifdef CONFIG_NO_HZ_FULL
if (tick_nohz_full_cpu(smp_processor_id()) &&
- (!rcu_gp_in_progress(rsp) ||
+ (!rcu_gp_in_progress() ||
ULONG_CMP_LT(jiffies, READ_ONCE(rsp->gp_start) + HZ)))
return true;
#endif /* #ifdef CONFIG_NO_HZ_FULL */
--
2.17.1