arch/sh/kernel/smp.c - third_party/linux - Git at Google

 /*
  * arch/sh/kernel/smp.c
  *
  * SMP support for the SuperH processors.
  *
  * Copyright (C) 2002 - 2007 Paul Mundt
  * Copyright (C) 2006 - 2007 Akio Idehara
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  */
 #include <linux/err.h>
 #include <linux/cache.h>
 #include <linux/cpumask.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/mm.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
 #include <asm/atomic.h>
 #include <asm/processor.h>
 #include <asm/system.h>
 #include <asm/mmu_context.h>
 #include <asm/smp.h>
 #include <asm/cacheflush.h>
 #include <asm/sections.h>

 int __cpu_number_map[NR_CPUS];		/* Map physical to logical */
 int __cpu_logical_map[NR_CPUS];		/* Map logical to physical */

 cpumask_t cpu_possible_map;
 EXPORT_SYMBOL(cpu_possible_map);

 cpumask_t cpu_online_map;
 EXPORT_SYMBOL(cpu_online_map);

 static atomic_t cpus_booted = ATOMIC_INIT(0);

 /*
  * Run specified function on a particular processor.
  */
 void __smp_call_function(unsigned int cpu);

 static inline void __init smp_store_cpu_info(unsigned int cpu)
 {
 	struct sh_cpuinfo *c = cpu_data + cpu;

 	c->loops_per_jiffy = loops_per_jiffy;
 }

 void __init smp_prepare_cpus(unsigned int max_cpus)
 {
 	unsigned int cpu = smp_processor_id();

 	init_new_context(current, &init_mm);
 	current_thread_info()->cpu = cpu;
 	plat_prepare_cpus(max_cpus);

 #ifndef CONFIG_HOTPLUG_CPU
 	cpu_present_map = cpu_possible_map;
 #endif
 }

 void __devinit smp_prepare_boot_cpu(void)
 {
 	unsigned int cpu = smp_processor_id();

 	__cpu_number_map[0] = cpu;
 	__cpu_logical_map[0] = cpu;

 	cpu_set(cpu, cpu_online_map);
 	cpu_set(cpu, cpu_possible_map);
 }

 asmlinkage void __cpuinit start_secondary(void)
 {
 	unsigned int cpu;
 	struct mm_struct *mm = &init_mm;

 	atomic_inc(&mm->mm_count);
 	atomic_inc(&mm->mm_users);
 	current->active_mm = mm;
 	BUG_ON(current->mm);
 	enter_lazy_tlb(mm, current);

 	per_cpu_trap_init();

 	preempt_disable();

 	local_irq_enable();

 	calibrate_delay();

 	cpu = smp_processor_id();
 	smp_store_cpu_info(cpu);

 	cpu_set(cpu, cpu_online_map);

 	cpu_idle();
 }

 extern struct {
 	unsigned long sp;
 	unsigned long bss_start;
 	unsigned long bss_end;
 	void *start_kernel_fn;
 	void *cpu_init_fn;
 	void *thread_info;
 } stack_start;

 int __cpuinit __cpu_up(unsigned int cpu)
 {
 	struct task_struct *tsk;
 	unsigned long timeout;

 	tsk = fork_idle(cpu);
 	if (IS_ERR(tsk)) {
 		printk(KERN_ERR "Failed forking idle task for cpu %d\n", cpu);
 		return PTR_ERR(tsk);
 	}

 	/* Fill in data in head.S for secondary cpus */
 	stack_start.sp = tsk->thread.sp;
 	stack_start.thread_info = tsk->stack;
 	stack_start.bss_start = 0; /* don't clear bss for secondary cpus */
 	stack_start.start_kernel_fn = start_secondary;

 	flush_cache_all();

 	plat_start_cpu(cpu, (unsigned long)_stext);

 	timeout = jiffies + HZ;
 	while (time_before(jiffies, timeout)) {
 		if (cpu_online(cpu))
 			break;

 		udelay(10);
 	}

 	if (cpu_online(cpu))
 		return 0;

 	return -ENOENT;
 }

 void __init smp_cpus_done(unsigned int max_cpus)
 {
 	unsigned long bogosum = 0;
 	int cpu;

 	for_each_online_cpu(cpu)
 		bogosum += cpu_data[cpu].loops_per_jiffy;

 	printk(KERN_INFO "SMP: Total of %d processors activated "
 	       "(%lu.%02lu BogoMIPS).\n", num_online_cpus(),
 	       bogosum / (500000/HZ),
 	       (bogosum / (5000/HZ)) % 100);
 }

 void smp_send_reschedule(int cpu)
 {
 	plat_send_ipi(cpu, SMP_MSG_RESCHEDULE);
 }

 static void stop_this_cpu(void *unused)
 {
 	cpu_clear(smp_processor_id(), cpu_online_map);
 	local_irq_disable();

 	for (;;)
 		cpu_relax();
 }

 void smp_send_stop(void)
 {
 	smp_call_function(stop_this_cpu, 0, 1, 0);
 }

 struct smp_fn_call_struct smp_fn_call = {
 	.lock		= SPIN_LOCK_UNLOCKED,
 	.finished	= ATOMIC_INIT(0),
 };

 /*
  * The caller of this wants the passed function to run on every cpu.  If wait
  * is set, wait until all cpus have finished the function before returning.
  * The lock is here to protect the call structure.
  * You must not call this function with disabled interrupts or from a
  * hardware interrupt handler or from a bottom half handler.
  */
 int smp_call_function(void (*func)(void *info), void *info, int retry, int wait)
 {
 	unsigned int nr_cpus = atomic_read(&cpus_booted);
 	int i;

 	/* Can deadlock when called with interrupts disabled */
 	WARN_ON(irqs_disabled());

 	spin_lock(&smp_fn_call.lock);

 	atomic_set(&smp_fn_call.finished, 0);
 	smp_fn_call.fn = func;
 	smp_fn_call.data = info;

 	for (i = 0; i < nr_cpus; i++)
 		if (i != smp_processor_id())
 			plat_send_ipi(i, SMP_MSG_FUNCTION);

 	if (wait)
 		while (atomic_read(&smp_fn_call.finished) != (nr_cpus - 1));

 	spin_unlock(&smp_fn_call.lock);

 	return 0;
 }

 /* Not really SMP stuff ... */
 int setup_profiling_timer(unsigned int multiplier)
 {
 	return 0;
 }

 static void flush_tlb_all_ipi(void *info)
 {
 	local_flush_tlb_all();
 }

 void flush_tlb_all(void)
 {
 	on_each_cpu(flush_tlb_all_ipi, 0, 1, 1);
 }

 static void flush_tlb_mm_ipi(void *mm)
 {
 	local_flush_tlb_mm((struct mm_struct *)mm);
 }

 /*
  * The following tlb flush calls are invoked when old translations are
  * being torn down, or pte attributes are changing. For single threaded
  * address spaces, a new context is obtained on the current cpu, and tlb
  * context on other cpus are invalidated to force a new context allocation
  * at switch_mm time, should the mm ever be used on other cpus. For
  * multithreaded address spaces, intercpu interrupts have to be sent.
  * Another case where intercpu interrupts are required is when the target
  * mm might be active on another cpu (eg debuggers doing the flushes on
  * behalf of debugees, kswapd stealing pages from another process etc).
  * Kanoj 07/00.
  */

 void flush_tlb_mm(struct mm_struct *mm)
 {
 	preempt_disable();

 	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
 		smp_call_function(flush_tlb_mm_ipi, (void *)mm, 1, 1);
 	} else {
 		int i;
 		for (i = 0; i < num_online_cpus(); i++)
 			if (smp_processor_id() != i)
 				cpu_context(i, mm) = 0;
 	}
 	local_flush_tlb_mm(mm);

 	preempt_enable();
 }

 struct flush_tlb_data {
 	struct vm_area_struct *vma;
 	unsigned long addr1;
 	unsigned long addr2;
 };

 static void flush_tlb_range_ipi(void *info)
 {
 	struct flush_tlb_data *fd = (struct flush_tlb_data *)info;

 	local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
 }

 void flush_tlb_range(struct vm_area_struct *vma,
 		     unsigned long start, unsigned long end)
 {
 	struct mm_struct *mm = vma->vm_mm;

 	preempt_disable();
 	if ((atomic_read(&mm->mm_users) != 1) || (current->mm != mm)) {
 		struct flush_tlb_data fd;

 		fd.vma = vma;
 		fd.addr1 = start;
 		fd.addr2 = end;
 		smp_call_function(flush_tlb_range_ipi, (void *)&fd, 1, 1);
 	} else {
 		int i;
 		for (i = 0; i < num_online_cpus(); i++)
 			if (smp_processor_id() != i)
 				cpu_context(i, mm) = 0;
 	}
 	local_flush_tlb_range(vma, start, end);
 	preempt_enable();
 }

 static void flush_tlb_kernel_range_ipi(void *info)
 {
 	struct flush_tlb_data *fd = (struct flush_tlb_data *)info;

 	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
 }

 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 {
 	struct flush_tlb_data fd;

 	fd.addr1 = start;
 	fd.addr2 = end;
 	on_each_cpu(flush_tlb_kernel_range_ipi, (void *)&fd, 1, 1);
 }

 static void flush_tlb_page_ipi(void *info)
 {
 	struct flush_tlb_data *fd = (struct flush_tlb_data *)info;

 	local_flush_tlb_page(fd->vma, fd->addr1);
 }

 void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
 {
 	preempt_disable();
 	if ((atomic_read(&vma->vm_mm->mm_users) != 1) ||
 	    (current->mm != vma->vm_mm)) {
 		struct flush_tlb_data fd;

 		fd.vma = vma;
 		fd.addr1 = page;
 		smp_call_function(flush_tlb_page_ipi, (void *)&fd, 1, 1);
 	} else {
 		int i;
 		for (i = 0; i < num_online_cpus(); i++)
 			if (smp_processor_id() != i)
 				cpu_context(i, vma->vm_mm) = 0;
 	}
 	local_flush_tlb_page(vma, page);
 	preempt_enable();
 }

 static void flush_tlb_one_ipi(void *info)
 {
 	struct flush_tlb_data *fd = (struct flush_tlb_data *)info;
 	local_flush_tlb_one(fd->addr1, fd->addr2);
 }

 void flush_tlb_one(unsigned long asid, unsigned long vaddr)
 {
 	struct flush_tlb_data fd;

 	fd.addr1 = asid;
 	fd.addr2 = vaddr;

 	smp_call_function(flush_tlb_one_ipi, (void *)&fd, 1, 1);
 	local_flush_tlb_one(asid, vaddr);
 }
	/*
	* arch/sh/kernel/smp.c
	*
	* SMP support for the SuperH processors.
	*
	* Copyright (C) 2002 - 2007 Paul Mundt
	* Copyright (C) 2006 - 2007 Akio Idehara
	*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*/
	#include <linux/err.h>
	#include <linux/cache.h>
	#include <linux/cpumask.h>
	#include <linux/delay.h>
	#include <linux/init.h>
	#include <linux/spinlock.h>
	#include <linux/mm.h>
	#include <linux/module.h>
	#include <linux/interrupt.h>
	#include <asm/atomic.h>
	#include <asm/processor.h>
	#include <asm/system.h>
	#include <asm/mmu_context.h>
	#include <asm/smp.h>
	#include <asm/cacheflush.h>
	#include <asm/sections.h>

	int __cpu_number_map[NR_CPUS]; /* Map physical to logical */
	int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */

	cpumask_t cpu_possible_map;
	EXPORT_SYMBOL(cpu_possible_map);

	cpumask_t cpu_online_map;
	EXPORT_SYMBOL(cpu_online_map);

	static atomic_t cpus_booted = ATOMIC_INIT(0);

	/*
	* Run specified function on a particular processor.
	*/
	void __smp_call_function(unsigned int cpu);

	static inline void __init smp_store_cpu_info(unsigned int cpu)
	{
	struct sh_cpuinfo *c = cpu_data + cpu;

	c->loops_per_jiffy = loops_per_jiffy;
	}

	void __init smp_prepare_cpus(unsigned int max_cpus)
	{
	unsigned int cpu = smp_processor_id();

	init_new_context(current, &init_mm);
	current_thread_info()->cpu = cpu;
	plat_prepare_cpus(max_cpus);

	#ifndef CONFIG_HOTPLUG_CPU
	cpu_present_map = cpu_possible_map;
	#endif
	}

	void __devinit smp_prepare_boot_cpu(void)
	{
	unsigned int cpu = smp_processor_id();

	__cpu_number_map[0] = cpu;
	__cpu_logical_map[0] = cpu;

	cpu_set(cpu, cpu_online_map);
	cpu_set(cpu, cpu_possible_map);
	}

	asmlinkage void __cpuinit start_secondary(void)
	{
	unsigned int cpu;
	struct mm_struct *mm = &init_mm;

	atomic_inc(&mm->mm_count);
	atomic_inc(&mm->mm_users);
	current->active_mm = mm;
	BUG_ON(current->mm);
	enter_lazy_tlb(mm, current);

	per_cpu_trap_init();

	preempt_disable();

	local_irq_enable();

	calibrate_delay();

	cpu = smp_processor_id();
	smp_store_cpu_info(cpu);

	cpu_set(cpu, cpu_online_map);

	cpu_idle();
	}

	extern struct {
	unsigned long sp;
	unsigned long bss_start;
	unsigned long bss_end;
	void *start_kernel_fn;
	void *cpu_init_fn;
	void *thread_info;
	} stack_start;

	int __cpuinit __cpu_up(unsigned int cpu)
	{
	struct task_struct *tsk;
	unsigned long timeout;

	tsk = fork_idle(cpu);
	if (IS_ERR(tsk)) {
	printk(KERN_ERR "Failed forking idle task for cpu %d\n", cpu);
	return PTR_ERR(tsk);
	}

	/* Fill in data in head.S for secondary cpus */
	stack_start.sp = tsk->thread.sp;
	stack_start.thread_info = tsk->stack;
	stack_start.bss_start = 0; /* don't clear bss for secondary cpus */
	stack_start.start_kernel_fn = start_secondary;

	flush_cache_all();

	plat_start_cpu(cpu, (unsigned long)_stext);

	timeout = jiffies + HZ;
	while (time_before(jiffies, timeout)) {
	if (cpu_online(cpu))
	break;

	udelay(10);
	}

	if (cpu_online(cpu))
	return 0;

	return -ENOENT;
	}

	void __init smp_cpus_done(unsigned int max_cpus)
	{
	unsigned long bogosum = 0;
	int cpu;

	for_each_online_cpu(cpu)
	bogosum += cpu_data[cpu].loops_per_jiffy;

	printk(KERN_INFO "SMP: Total of %d processors activated "
	"(%lu.%02lu BogoMIPS).\n", num_online_cpus(),
	bogosum / (500000/HZ),
	(bogosum / (5000/HZ)) % 100);
	}

	void smp_send_reschedule(int cpu)
	{
	plat_send_ipi(cpu, SMP_MSG_RESCHEDULE);
	}

	static void stop_this_cpu(void *unused)
	{
	cpu_clear(smp_processor_id(), cpu_online_map);
	local_irq_disable();

	for (;;)
	cpu_relax();
	}

	void smp_send_stop(void)
	{
	smp_call_function(stop_this_cpu, 0, 1, 0);
	}

	struct smp_fn_call_struct smp_fn_call = {
	.lock = SPIN_LOCK_UNLOCKED,
	.finished = ATOMIC_INIT(0),
	};

	/*
	* The caller of this wants the passed function to run on every cpu. If wait
	* is set, wait until all cpus have finished the function before returning.
	* The lock is here to protect the call structure.
	* You must not call this function with disabled interrupts or from a
	* hardware interrupt handler or from a bottom half handler.
	*/
	int smp_call_function(void (func)(void info), void *info, int retry, int wait)
	{
	unsigned int nr_cpus = atomic_read(&cpus_booted);
	int i;

	/* Can deadlock when called with interrupts disabled */
	WARN_ON(irqs_disabled());

	spin_lock(&smp_fn_call.lock);

	atomic_set(&smp_fn_call.finished, 0);
	smp_fn_call.fn = func;
	smp_fn_call.data = info;

	for (i = 0; i < nr_cpus; i++)
	if (i != smp_processor_id())
	plat_send_ipi(i, SMP_MSG_FUNCTION);

	if (wait)
	while (atomic_read(&smp_fn_call.finished) != (nr_cpus - 1));

	spin_unlock(&smp_fn_call.lock);

	return 0;
	}

	/* Not really SMP stuff ... */
	int setup_profiling_timer(unsigned int multiplier)
	{
	return 0;
	}

	static void flush_tlb_all_ipi(void *info)
	{
	local_flush_tlb_all();
	}

	void flush_tlb_all(void)
	{
	on_each_cpu(flush_tlb_all_ipi, 0, 1, 1);
	}

	static void flush_tlb_mm_ipi(void *mm)
	{
	local_flush_tlb_mm((struct mm_struct *)mm);
	}

	/*
	* The following tlb flush calls are invoked when old translations are
	* being torn down, or pte attributes are changing. For single threaded
	* address spaces, a new context is obtained on the current cpu, and tlb
	* context on other cpus are invalidated to force a new context allocation
	* at switch_mm time, should the mm ever be used on other cpus. For
	* multithreaded address spaces, intercpu interrupts have to be sent.
	* Another case where intercpu interrupts are required is when the target
	* mm might be active on another cpu (eg debuggers doing the flushes on
	* behalf of debugees, kswapd stealing pages from another process etc).
	* Kanoj 07/00.
	*/

	void flush_tlb_mm(struct mm_struct *mm)
	{
	preempt_disable();

	if ((atomic_read(&mm->mm_users) != 1) \|\| (current->mm != mm)) {
	smp_call_function(flush_tlb_mm_ipi, (void *)mm, 1, 1);
	} else {
	int i;
	for (i = 0; i < num_online_cpus(); i++)
	if (smp_processor_id() != i)
	cpu_context(i, mm) = 0;
	}
	local_flush_tlb_mm(mm);

	preempt_enable();
	}

	struct flush_tlb_data {
	struct vm_area_struct *vma;
	unsigned long addr1;
	unsigned long addr2;
	};

	static void flush_tlb_range_ipi(void *info)
	{
	struct flush_tlb_data fd = (struct flush_tlb_data )info;

	local_flush_tlb_range(fd->vma, fd->addr1, fd->addr2);
	}

	void flush_tlb_range(struct vm_area_struct *vma,
	unsigned long start, unsigned long end)
	{
	struct mm_struct *mm = vma->vm_mm;

	preempt_disable();
	if ((atomic_read(&mm->mm_users) != 1) \|\| (current->mm != mm)) {
	struct flush_tlb_data fd;

	fd.vma = vma;
	fd.addr1 = start;
	fd.addr2 = end;
	smp_call_function(flush_tlb_range_ipi, (void *)&fd, 1, 1);
	} else {
	int i;
	for (i = 0; i < num_online_cpus(); i++)
	if (smp_processor_id() != i)
	cpu_context(i, mm) = 0;
	}
	local_flush_tlb_range(vma, start, end);
	preempt_enable();
	}

	static void flush_tlb_kernel_range_ipi(void *info)
	{
	struct flush_tlb_data fd = (struct flush_tlb_data )info;

	local_flush_tlb_kernel_range(fd->addr1, fd->addr2);
	}

	void flush_tlb_kernel_range(unsigned long start, unsigned long end)
	{
	struct flush_tlb_data fd;

	fd.addr1 = start;
	fd.addr2 = end;
	on_each_cpu(flush_tlb_kernel_range_ipi, (void *)&fd, 1, 1);
	}

	static void flush_tlb_page_ipi(void *info)
	{
	struct flush_tlb_data fd = (struct flush_tlb_data )info;

	local_flush_tlb_page(fd->vma, fd->addr1);
	}

	void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
	{
	preempt_disable();
	if ((atomic_read(&vma->vm_mm->mm_users) != 1) \|\|
	(current->mm != vma->vm_mm)) {
	struct flush_tlb_data fd;

	fd.vma = vma;
	fd.addr1 = page;
	smp_call_function(flush_tlb_page_ipi, (void *)&fd, 1, 1);
	} else {
	int i;
	for (i = 0; i < num_online_cpus(); i++)
	if (smp_processor_id() != i)
	cpu_context(i, vma->vm_mm) = 0;
	}
	local_flush_tlb_page(vma, page);
	preempt_enable();
	}

	static void flush_tlb_one_ipi(void *info)
	{
	struct flush_tlb_data fd = (struct flush_tlb_data )info;
	local_flush_tlb_one(fd->addr1, fd->addr2);
	}

	void flush_tlb_one(unsigned long asid, unsigned long vaddr)
	{
	struct flush_tlb_data fd;

	fd.addr1 = asid;
	fd.addr2 = vaddr;

	smp_call_function(flush_tlb_one_ipi, (void *)&fd, 1, 1);
	local_flush_tlb_one(asid, vaddr);
	}