[PATCH 1/3] tick/rcu: Remove obsolete rcu_needs_cpu() parameters

Frederic Weisbecker
2022-02-08T16:16:48Z

With the removal of CONFIG_RCU_FAST_NO_HZ, the parameters in
rcu_needs_cpu() are not necessary anymore. Simply remove them.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Paul Menzel <pmenzel@molgen.mpg.de>
---
include/linux/rcutiny.h | 3 +--
include/linux/rcutree.h | 2 +-
kernel/rcu/tree.c | 3 +--
kernel/time/tick-sched.c | 10 ++++------
4 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/include/linux/rcutiny.h b/include/linux/rcutiny.h
index 858f4d429946..5fed476f977f 100644
--- a/include/linux/rcutiny.h
+++ b/include/linux/rcutiny.h
@@ -64,9 +64,8 @@ static inline void rcu_softirq_qs(void)
rcu_tasks_qs(current, (preempt)); \
} while (0)

-static inline int rcu_needs_cpu(u64 basemono, u64 *nextevt)
+static inline int rcu_needs_cpu(void)
{
- *nextevt = KTIME_MAX;
return 0;
}

diff --git a/include/linux/rcutree.h b/include/linux/rcutree.h
index 53209d669400..6cc91291d078 100644
--- a/include/linux/rcutree.h
+++ b/include/linux/rcutree.h
@@ -19,7 +19,7 @@

void rcu_softirq_qs(void);
void rcu_note_context_switch(bool preempt);
-int rcu_needs_cpu(u64 basem, u64 *nextevt);
+int rcu_needs_cpu(void);
void rcu_cpu_stall_reset(void);

/*
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index a4c25a6283b0..80faf2273ce9 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1086,9 +1086,8 @@ void rcu_irq_enter_irqson(void)
* Just check whether or not this CPU has non-offloaded RCU callbacks
* queued.
*/
-int rcu_needs_cpu(u64 basemono, u64 *nextevt)
+int rcu_needs_cpu(void)
{
- *nextevt = KTIME_MAX;
return !rcu_segcblist_empty(&this_cpu_ptr(&rcu_data)->cblist) &&
!rcu_rdp_is_offloaded(this_cpu_ptr(&rcu_data));
}
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 17a283ce2b20..2abb5112feb9 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -768,7 +768,7 @@ static inline bool local_timer_softirq_pending(void)

static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
{
- u64 basemono, next_tick, next_tmr, next_rcu, delta, expires;
+ u64 basemono, next_tick, delta, expires;
unsigned long basejiff;
unsigned int seq;

@@ -791,7 +791,7 @@ static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
* minimal delta which brings us back to this place
* immediately. Lather, rinse and repeat...
*/
- if (rcu_needs_cpu(basemono, &next_rcu) || arch_needs_cpu() ||
+ if (rcu_needs_cpu() || arch_needs_cpu() ||
irq_work_needs_cpu() || local_timer_softirq_pending()) {
next_tick = basemono + TICK_NSEC;
} else {
@@ -802,10 +802,8 @@ static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu)
* disabled this also looks at the next expiring
* hrtimer.
*/
- next_tmr = get_next_timer_interrupt(basejiff, basemono);
- ts->next_timer = next_tmr;
- /* Take the next rcu event into account */
- next_tick = next_rcu < next_tmr ? next_rcu : next_tmr;
+ next_tick = get_next_timer_interrupt(basejiff, basemono);
+ ts->next_timer = next_tick;
}

/*
--
2.25.1