From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755339AbaJ1V6H (ORCPT ); Tue, 28 Oct 2014 17:58:07 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:51223 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751390AbaJ1V5f (ORCPT ); Tue, 28 Oct 2014 17:57:35 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 03/10] rcu: Remove "cpu" argument to rcu_check_callbacks() Date: Tue, 28 Oct 2014 14:53:30 -0700 Message-Id: <1414533217-24910-3-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1414533217-24910-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20141028215140.GA23970@linux.vnet.ibm.com> <1414533217-24910-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14102821-0025-0000-0000-000000F04B2D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" 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 However, this offload approach has been replaced by NO_HZ_FULL, which offloads -all- RCU processing from qualifying CPUs.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 --- 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(); -- 1.8.1.5