Subject: [PATCHv6 11/11] ARM: smp: Remove local timer API

From: [email-masked] (Stephen Boyd)
Date: Mon, 13 May 2013 12:26:15 -0700

There are no more users of this API, remove it.

Cc: Russell King <[email-masked]>
Acked-by: Tony Lindgren <[email-masked]>
Signed-off-by: Stephen Boyd <[email-masked]>
---
 arch/arm/Kconfig                  | 10 ------
 arch/arm/include/asm/localtimer.h | 34 -------------------
 arch/arm/kernel/smp.c             | 69 ---------------------------------------
 3 files changed, 113 deletions(-)
 delete mode 100644 arch/arm/include/asm/localtimer.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 177cb39..626a272 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1542,16 +1542,6 @@ config ARM_PSCI
 	  0022A ("Power State Coordination Interface System Software on
 	  ARM processors").
 
-config LOCAL_TIMERS
-	bool "Use local timer interrupts"
-	depends on SMP
-	default y
-	help
-	  Enable support for local timers on SMP platforms, rather then the
-	  legacy IPI broadcast method.  Local timers allows the system
-	  accounting to be spread across the timer interval, preventing a
-	  "thundering herd" at every timer tick.
-
 # The GPIO number here must be sorted by descending number. In case of
 # a multiplatform kernel, we just want the highest value required by the
 # selected platforms.
diff --git a/arch/arm/include/asm/localtimer.h b/arch/arm/include/asm/localtimer.h
deleted file mode 100644
index f77ffc1..0000000
--- a/arch/arm/include/asm/localtimer.h
+++ /dev/null
@@ -1,34 +0,0 @@
-/*
- *  arch/arm/include/asm/localtimer.h
- *
- *  Copyright (C) 2004-2005 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#ifndef __ASM_ARM_LOCALTIMER_H
-#define __ASM_ARM_LOCALTIMER_H
-
-#include <linux/errno.h>
-
-struct clock_event_device;
-
-struct local_timer_ops {
-	int  (*setup)(struct clock_event_device *);
-	void (*stop)(struct clock_event_device *);
-};
-
-#ifdef CONFIG_LOCAL_TIMERS
-/*
- * Register a local timer driver
- */
-int local_timer_register(struct local_timer_ops *);
-#else
-static inline int local_timer_register(struct local_timer_ops *ops)
-{
-	return -ENXIO;
-}
-#endif
-
-#endif
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 4dc883a..54aa994 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -41,7 +41,6 @@
 #include <asm/sections.h>
 #include <asm/tlbflush.h>
 #include <asm/ptrace.h>
-#include <asm/localtimer.h>
 #include <asm/smp_plat.h>
 #include <asm/virt.h>
 #include <asm/mach/arch.h>
@@ -133,8 +132,6 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
-static void percpu_timer_stop(void);
-
 static int platform_cpu_kill(unsigned int cpu)
 {
 	if (smp_ops.cpu_kill)
@@ -178,11 +175,6 @@ int __cpuinit __cpu_disable(void)
 	migrate_irqs();
 
 	/*
-	 * Stop the local timer for this CPU.
-	 */
-	percpu_timer_stop();
-
-	/*
 	 * Flush user cache and TLB mappings, and then remove this CPU
 	 * from the vm mask set of all processes.
 	 *
@@ -303,8 +295,6 @@ static void __cpuinit smp_store_cpu_info(unsigned int cpuid)
 	store_cpu_topology(cpuid);
 }
 
-static void percpu_timer_setup(void);
-
 /*
  * This is the secondary CPU boot entry.  We're using this CPUs
  * idle thread stack, but a set of temporary page tables.
@@ -359,11 +349,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void)
 	set_cpu_online(cpu, true);
 	complete(&cpu_running);
 
-	/*
-	 * Setup the percpu timer for this CPU.
-	 */
-	percpu_timer_setup();
-
 	local_irq_enable();
 	local_fiq_enable();
 
@@ -410,12 +395,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 		max_cpus = ncores;
 	if (ncores > 1 && max_cpus) {
 		/*
-		 * Enable the local timer or broadcast device for the
-		 * boot CPU, but only if we have more than one CPU.
-		 */
-		percpu_timer_setup();
-
-		/*
 		 * Initialise the present map, which describes the set of CPUs
 		 * actually populated at the present time. A platform should
 		 * re-initialize the map in the platforms smp_prepare_cpus()
@@ -491,11 +470,6 @@ u64 smp_irq_stat_cpu(unsigned int cpu)
 	return sum;
 }
 
-/*
- * Timer (local or broadcast) support
- */
-static DEFINE_PER_CPU(struct clock_event_device, percpu_clockevent);
-
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
 void tick_broadcast(const struct cpumask *mask)
 {
@@ -503,49 +477,6 @@ void tick_broadcast(const struct cpumask *mask)
 }
 #endif
 
-static struct local_timer_ops *lt_ops;
-
-#ifdef CONFIG_LOCAL_TIMERS
-int local_timer_register(struct local_timer_ops *ops)
-{
-	if (!is_smp() || !setup_max_cpus)
-		return -ENXIO;
-
-	if (lt_ops)
-		return -EBUSY;
-
-	lt_ops = ops;
-	return 0;
-}
-#endif
-
-static void __cpuinit percpu_timer_setup(void)
-{
-	unsigned int cpu = smp_processor_id();
-	struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
-	evt->cpumask = cpumask_of(cpu);
-
-	if (lt_ops)
-		lt_ops->setup(evt);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-/*
- * The generic clock events code purposely does not stop the local timer
- * on CPU_DEAD/CPU_DEAD_FROZEN hotplug events, so we have to do it
- * manually here.
- */
-static void percpu_timer_stop(void)
-{
-	unsigned int cpu = smp_processor_id();
-	struct clock_event_device *evt = &per_cpu(percpu_clockevent, cpu);
-
-	if (lt_ops)
-		lt_ops->stop(evt);
-}
-#endif
-
 static DEFINE_RAW_SPINLOCK(stop_lock);
 
 /*
-- 
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