linux/arch/mips/kernel/smp.c
Yong Zhang b789ad63ac MIPS: smp: Warn on too early irq enable
Just to catch a potential issue.

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: David Daney <david.daney@cavium.com>
Acked-by: David Daney <david.daney@cavium.com>
Patchwork: https://patchwork.linux-mips.org/patch/3852/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-07-19 11:23:44 +02:00

387 lines
8.9 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) 2000, 2001 Kanoj Sarcar
* Copyright (C) 2000, 2001 Ralf Baechle
* Copyright (C) 2000, 2001 Silicon Graphics, Inc.
* Copyright (C) 2000, 2001, 2003 Broadcom Corporation
*/
#include <linux/cache.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/threads.h>
#include <linux/module.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/sched.h>
#include <linux/cpumask.h>
#include <linux/cpu.h>
#include <linux/err.h>
#include <linux/ftrace.h>
#include <linux/atomic.h>
#include <asm/cpu.h>
#include <asm/processor.h>
#include <asm/r4k-timer.h>
#include <asm/mmu_context.h>
#include <asm/time.h>
#include <asm/setup.h>
#ifdef CONFIG_MIPS_MT_SMTC
#include <asm/mipsmtregs.h>
#endif /* CONFIG_MIPS_MT_SMTC */
volatile cpumask_t cpu_callin_map; /* Bitmask of started secondaries */
int __cpu_number_map[NR_CPUS]; /* Map physical to logical */
EXPORT_SYMBOL(__cpu_number_map);
int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */
EXPORT_SYMBOL(__cpu_logical_map);
/* Number of TCs (or siblings in Intel speak) per CPU core */
int smp_num_siblings = 1;
EXPORT_SYMBOL(smp_num_siblings);
/* representing the TCs (or siblings in Intel speak) of each logical CPU */
cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(cpu_sibling_map);
/* representing cpus for which sibling maps can be computed */
static cpumask_t cpu_sibling_setup_map;
static inline void set_cpu_sibling_map(int cpu)
{
int i;
cpu_set(cpu, cpu_sibling_setup_map);
if (smp_num_siblings > 1) {
for_each_cpu_mask(i, cpu_sibling_setup_map) {
if (cpu_data[cpu].core == cpu_data[i].core) {
cpu_set(i, cpu_sibling_map[cpu]);
cpu_set(cpu, cpu_sibling_map[i]);
}
}
} else
cpu_set(cpu, cpu_sibling_map[cpu]);
}
struct plat_smp_ops *mp_ops;
__cpuinit void register_smp_ops(struct plat_smp_ops *ops)
{
if (mp_ops)
printk(KERN_WARNING "Overriding previously set SMP ops\n");
mp_ops = ops;
}
/*
* First C code run on the secondary CPUs after being started up by
* the master.
*/
asmlinkage __cpuinit void start_secondary(void)
{
unsigned int cpu;
#ifdef CONFIG_MIPS_MT_SMTC
/* Only do cpu_probe for first TC of CPU */
if ((read_c0_tcbind() & TCBIND_CURTC) == 0)
#endif /* CONFIG_MIPS_MT_SMTC */
cpu_probe();
cpu_report();
per_cpu_trap_init(false);
mips_clockevent_init();
mp_ops->init_secondary();
/*
* XXX parity protection should be folded in here when it's converted
* to an option instead of something based on .cputype
*/
calibrate_delay();
preempt_disable();
cpu = smp_processor_id();
cpu_data[cpu].udelay_val = loops_per_jiffy;
notify_cpu_starting(cpu);
set_cpu_online(cpu, true);
set_cpu_sibling_map(cpu);
cpu_set(cpu, cpu_callin_map);
synchronise_count_slave();
/*
* irq will be enabled in ->smp_finish(), enabling it too early
* is dangerous.
*/
WARN_ON_ONCE(!irqs_disabled());
mp_ops->smp_finish();
cpu_idle();
}
/*
* Call into both interrupt handlers, as we share the IPI for them
*/
void __irq_entry smp_call_function_interrupt(void)
{
irq_enter();
generic_smp_call_function_single_interrupt();
generic_smp_call_function_interrupt();
irq_exit();
}
static void stop_this_cpu(void *dummy)
{
/*
* Remove this CPU:
*/
set_cpu_online(smp_processor_id(), false);
for (;;) {
if (cpu_wait)
(*cpu_wait)(); /* Wait if available. */
}
}
void smp_send_stop(void)
{
smp_call_function(stop_this_cpu, NULL, 0);
}
void __init smp_cpus_done(unsigned int max_cpus)
{
mp_ops->cpus_done();
synchronise_count_master();
}
/* called from main before smp_init() */
void __init smp_prepare_cpus(unsigned int max_cpus)
{
init_new_context(current, &init_mm);
current_thread_info()->cpu = 0;
mp_ops->prepare_cpus(max_cpus);
set_cpu_sibling_map(0);
#ifndef CONFIG_HOTPLUG_CPU
init_cpu_present(cpu_possible_mask);
#endif
}
/* preload SMP state for boot cpu */
void __devinit smp_prepare_boot_cpu(void)
{
set_cpu_possible(0, true);
set_cpu_online(0, true);
cpu_set(0, cpu_callin_map);
}
int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *tidle)
{
mp_ops->boot_secondary(cpu, tidle);
/*
* Trust is futile. We should really have timeouts ...
*/
while (!cpu_isset(cpu, cpu_callin_map))
udelay(100);
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, NULL, 1);
}
static void flush_tlb_mm_ipi(void *mm)
{
local_flush_tlb_mm((struct mm_struct *)mm);
}
/*
* Special Variant of smp_call_function for use by TLB functions:
*
* o No return value
* o collapses to normal function call on UP kernels
* o collapses to normal function call on systems with a single shared
* primary cache.
* o CONFIG_MIPS_MT_SMTC currently implies there is only one physical core.
*/
static inline void smp_on_other_tlbs(void (*func) (void *info), void *info)
{
#ifndef CONFIG_MIPS_MT_SMTC
smp_call_function(func, info, 1);
#endif
}
static inline void smp_on_each_tlb(void (*func) (void *info), void *info)
{
preempt_disable();
smp_on_other_tlbs(func, info);
func(info);
preempt_enable();
}
/*
* 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_on_other_tlbs(flush_tlb_mm_ipi, mm);
} else {
unsigned int cpu;
for_each_online_cpu(cpu) {
if (cpu != smp_processor_id() && cpu_context(cpu, mm))
cpu_context(cpu, 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 = 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 = {
.vma = vma,
.addr1 = start,
.addr2 = end,
};
smp_on_other_tlbs(flush_tlb_range_ipi, &fd);
} else {
unsigned int cpu;
for_each_online_cpu(cpu) {
if (cpu != smp_processor_id() && cpu_context(cpu, mm))
cpu_context(cpu, 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 = 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 = {
.addr1 = start,
.addr2 = end,
};
on_each_cpu(flush_tlb_kernel_range_ipi, &fd, 1);
}
static void flush_tlb_page_ipi(void *info)
{
struct flush_tlb_data *fd = 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 = {
.vma = vma,
.addr1 = page,
};
smp_on_other_tlbs(flush_tlb_page_ipi, &fd);
} else {
unsigned int cpu;
for_each_online_cpu(cpu) {
if (cpu != smp_processor_id() && cpu_context(cpu, vma->vm_mm))
cpu_context(cpu, vma->vm_mm) = 0;
}
}
local_flush_tlb_page(vma, page);
preempt_enable();
}
static void flush_tlb_one_ipi(void *info)
{
unsigned long vaddr = (unsigned long) info;
local_flush_tlb_one(vaddr);
}
void flush_tlb_one(unsigned long vaddr)
{
smp_on_each_tlb(flush_tlb_one_ipi, (void *) vaddr);
}
EXPORT_SYMBOL(flush_tlb_page);
EXPORT_SYMBOL(flush_tlb_one);