From c3377c2da6e594504c900d5ef72374c109e4ca99 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 21 Oct 2014 07:53:02 -0700 Subject: [PATCH] rcu: Remove "cpu" argument to rcu_check_callbacks() The "cpu" argument was kept around on the off-chance that RCU might offload scheduler-clock interrupts. However, this offload approach has been replaced by NO_HZ_FULL, which offloads -all- RCU processing from qualifying CPUs. It is therefore time to remove the "cpu" argument to rcu_check_callbacks(), which this commit does. Signed-off-by: Paul E. McKenney Reviewed-by: Pranith Kumar --- include/linux/rcupdate.h | 2 +- kernel/rcu/tiny.c | 2 +- kernel/rcu/tree.c | 6 +++--- kernel/time/timer.c | 3 +-- 4 files changed, 6 insertions(+), 7 deletions(-) diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index a4a819ffb2d1..b4ad275d90d0 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -260,7 +260,7 @@ static inline int rcu_preempt_depth(void) void rcu_init(void); void rcu_sched_qs(void); void rcu_bh_qs(void); -void rcu_check_callbacks(int cpu, int user); +void rcu_check_callbacks(int user); struct notifier_block; void rcu_idle_enter(void); void rcu_idle_exit(void); diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index c0623fc47125..01570c68d237 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -247,7 +247,7 @@ void rcu_bh_qs(void) * be called from hardirq context. It is normally called from the * scheduling-clock interrupt. */ -void rcu_check_callbacks(int cpu, int user) +void rcu_check_callbacks(int user) { RCU_TRACE(check_cpu_stalls()); if (user || rcu_is_cpu_rrupt_from_idle()) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index ab6fcfb4fe11..3107811bba69 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -2388,7 +2388,7 @@ static void rcu_do_batch(struct rcu_state *rsp, struct rcu_data *rdp) * invoked from the scheduling-clock interrupt. If rcu_pending returns * false, there is no point in invoking rcu_check_callbacks(). */ -void rcu_check_callbacks(int cpu, int user) +void rcu_check_callbacks(int user) { trace_rcu_utilization(TPS("Start scheduler-tick")); increment_cpu_stall_ticks(); @@ -2420,8 +2420,8 @@ void rcu_check_callbacks(int cpu, int user) rcu_bh_qs(); } - rcu_preempt_check_callbacks(cpu); - if (rcu_pending(cpu)) + rcu_preempt_check_callbacks(smp_processor_id()); + if (rcu_pending(smp_processor_id())) invoke_rcu_core(); if (user) rcu_note_voluntary_context_switch(current); diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 3260ffdb368f..2d3f5c504939 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -1377,12 +1377,11 @@ unsigned long get_next_timer_interrupt(unsigned long now) void update_process_times(int user_tick) { struct task_struct *p = current; - int cpu = smp_processor_id(); /* Note: this timer irq context must be accounted for as well. */ account_process_tick(p, user_tick); run_local_timers(); - rcu_check_callbacks(cpu, user_tick); + rcu_check_callbacks(user_tick); #ifdef CONFIG_IRQ_WORK if (in_irq()) irq_work_tick(); -- 2.20.1