MN10300: SMP TLB flushing

Implement global TLB flushing for MN10300.  This will be used by the AM34 which
is SMP capable.

Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com>
Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
This commit is contained in:
Akira Takeuchi 2010-10-27 17:28:51 +01:00 committed by David Howells
parent dccbf4853a
commit 965ea4bbb9
4 changed files with 288 additions and 27 deletions

View File

@ -36,6 +36,22 @@
#define enter_lazy_tlb(mm, tsk) do {} while (0)
static inline void cpu_ran_vm(int cpu, struct mm_struct *mm)
{
#ifdef CONFIG_SMP
cpumask_set_cpu(cpu, mm_cpumask(mm));
#endif
}
static inline bool cpu_maybe_ran_vm(int cpu, struct mm_struct *mm)
{
#ifdef CONFIG_SMP
return cpumask_test_and_set_cpu(cpu, mm_cpumask(mm));
#else
return true;
#endif
}
#ifdef CONFIG_MN10300_TLB_USE_PIDR
extern unsigned long mmu_context_cache[NR_CPUS];
#define mm_context(mm) (mm->context.tlbpid[smp_processor_id()])
@ -127,7 +143,13 @@ static inline void activate_context(struct mm_struct *mm)
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
int cpu = smp_processor_id();
if (prev != next) {
#ifdef CONFIG_SMP
per_cpu(cpu_tlbstate, cpu).active_mm = next;
#endif
cpu_ran_vm(cpu, next);
PTBR = (unsigned long) next->pgd;
activate_context(next);
}

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@ -11,6 +11,7 @@
#ifndef _ASM_TLBFLUSH_H
#define _ASM_TLBFLUSH_H
#include <linux/mm.h>
#include <asm/processor.h>
struct tlb_state {
@ -93,39 +94,61 @@ void local_flush_tlb_page(struct mm_struct *mm, unsigned long addr)
* - flush_tlb_range(mm, start, end) flushes a range of pages
* - flush_tlb_pgtables(mm, start, end) flushes a range of page tables
*/
#define flush_tlb_all() \
do { \
preempt_disable(); \
local_flush_tlb_all(); \
preempt_enable(); \
} while (0)
#ifdef CONFIG_SMP
#define flush_tlb_mm(mm) \
do { \
preempt_disable(); \
local_flush_tlb_all(); \
preempt_enable(); \
} while (0)
#include <asm/smp.h>
#define flush_tlb_range(vma, start, end) \
do { \
unsigned long __s __attribute__((unused)) = (start); \
unsigned long __e __attribute__((unused)) = (end); \
preempt_disable(); \
local_flush_tlb_all(); \
preempt_enable(); \
} while (0)
extern void flush_tlb_all(void);
extern void flush_tlb_current_task(void);
extern void flush_tlb_mm(struct mm_struct *);
extern void flush_tlb_page(struct vm_area_struct *, unsigned long);
#define flush_tlb() flush_tlb_current_task()
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
flush_tlb_mm(vma->vm_mm);
}
#else /* CONFIG_SMP */
static inline void flush_tlb_all(void)
{
preempt_disable();
local_flush_tlb_all();
preempt_enable();
}
static inline void flush_tlb_mm(struct mm_struct *mm)
{
preempt_disable();
local_flush_tlb_all();
preempt_enable();
}
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
preempt_disable();
local_flush_tlb_all();
preempt_enable();
}
#define flush_tlb_page(vma, addr) local_flush_tlb_page((vma)->vm_mm, addr)
#define flush_tlb() flush_tlb_all()
#define flush_tlb_kernel_range(start, end) \
do { \
unsigned long __s __attribute__((unused)) = (start); \
unsigned long __e __attribute__((unused)) = (end); \
flush_tlb_all(); \
} while (0)
#endif /* CONFIG_SMP */
#define flush_tlb_pgtables(mm, start, end) do {} while (0)
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
flush_tlb_all();
}
static inline void flush_tlb_pgtables(struct mm_struct *mm,
unsigned long start, unsigned long end)
{
}
#endif /* _ASM_TLBFLUSH_H */

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@ -18,3 +18,5 @@ cacheflush-$(CONFIG_MN10300_CACHE_DISABLED) := cache-disabled.o
obj-y := \
init.o fault.o pgtable.o extable.o tlb-mn10300.o mmu-context.o \
misalignment.o dma-alloc.o $(cacheflush-y)
obj-$(CONFIG_SMP) += tlb-smp.o

214
arch/mn10300/mm/tlb-smp.c Normal file
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@ -0,0 +1,214 @@
/* SMP TLB support routines.
*
* Copyright (C) 2006-2008 Panasonic Corporation
* All Rights Reserved.
*
* 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.
*
* 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.
*/
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/cpumask.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/profile.h>
#include <linux/smp.h>
#include <asm/tlbflush.h>
#include <asm/system.h>
#include <asm/bitops.h>
#include <asm/processor.h>
#include <asm/bug.h>
#include <asm/exceptions.h>
#include <asm/hardirq.h>
#include <asm/fpu.h>
#include <asm/mmu_context.h>
#include <asm/thread_info.h>
#include <asm/cpu-regs.h>
#include <asm/intctl-regs.h>
/*
* For flush TLB
*/
#define FLUSH_ALL 0xffffffff
static cpumask_t flush_cpumask;
static struct mm_struct *flush_mm;
static unsigned long flush_va;
static DEFINE_SPINLOCK(tlbstate_lock);
DEFINE_PER_CPU_SHARED_ALIGNED(struct tlb_state, cpu_tlbstate) = {
&init_mm, 0
};
static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
unsigned long va);
static void do_flush_tlb_all(void *info);
/**
* smp_flush_tlb - Callback to invalidate the TLB.
* @unused: Callback context (ignored).
*/
void smp_flush_tlb(void *unused)
{
unsigned long cpu_id;
cpu_id = get_cpu();
if (!cpu_isset(cpu_id, flush_cpumask))
/* This was a BUG() but until someone can quote me the line
* from the intel manual that guarantees an IPI to multiple
* CPUs is retried _only_ on the erroring CPUs its staying as a
* return
*
* BUG();
*/
goto out;
if (flush_va == FLUSH_ALL)
local_flush_tlb();
else
local_flush_tlb_page(flush_mm, flush_va);
smp_mb__before_clear_bit();
cpu_clear(cpu_id, flush_cpumask);
smp_mb__after_clear_bit();
out:
put_cpu();
}
/**
* flush_tlb_others - Tell the specified CPUs to invalidate their TLBs
* @cpumask: The list of CPUs to target.
* @mm: The VM context to flush from (if va!=FLUSH_ALL).
* @va: Virtual address to flush or FLUSH_ALL to flush everything.
*/
static void flush_tlb_others(cpumask_t cpumask, struct mm_struct *mm,
unsigned long va)
{
cpumask_t tmp;
/* A couple of sanity checks (to be removed):
* - mask must not be empty
* - current CPU must not be in mask
* - we do not send IPIs to as-yet unbooted CPUs.
*/
BUG_ON(!mm);
BUG_ON(cpus_empty(cpumask));
BUG_ON(cpu_isset(smp_processor_id(), cpumask));
cpus_and(tmp, cpumask, cpu_online_map);
BUG_ON(!cpus_equal(cpumask, tmp));
/* I'm not happy about this global shared spinlock in the MM hot path,
* but we'll see how contended it is.
*
* Temporarily this turns IRQs off, so that lockups are detected by the
* NMI watchdog.
*/
spin_lock(&tlbstate_lock);
flush_mm = mm;
flush_va = va;
#if NR_CPUS <= BITS_PER_LONG
atomic_set_mask(cpumask.bits[0], &flush_cpumask.bits[0]);
#else
#error Not supported.
#endif
/* FIXME: if NR_CPUS>=3, change send_IPI_mask */
smp_call_function(smp_flush_tlb, NULL, 1);
while (!cpus_empty(flush_cpumask))
/* Lockup detection does not belong here */
smp_mb();
flush_mm = NULL;
flush_va = 0;
spin_unlock(&tlbstate_lock);
}
/**
* flush_tlb_mm - Invalidate TLB of specified VM context
* @mm: The VM context to invalidate.
*/
void flush_tlb_mm(struct mm_struct *mm)
{
cpumask_t cpu_mask;
preempt_disable();
cpu_mask = mm->cpu_vm_mask;
cpu_clear(smp_processor_id(), cpu_mask);
local_flush_tlb();
if (!cpus_empty(cpu_mask))
flush_tlb_others(cpu_mask, mm, FLUSH_ALL);
preempt_enable();
}
/**
* flush_tlb_current_task - Invalidate TLB of current task
*/
void flush_tlb_current_task(void)
{
struct mm_struct *mm = current->mm;
cpumask_t cpu_mask;
preempt_disable();
cpu_mask = mm->cpu_vm_mask;
cpu_clear(smp_processor_id(), cpu_mask);
local_flush_tlb();
if (!cpus_empty(cpu_mask))
flush_tlb_others(cpu_mask, mm, FLUSH_ALL);
preempt_enable();
}
/**
* flush_tlb_page - Invalidate TLB of page
* @vma: The VM context to invalidate the page for.
* @va: The virtual address of the page to invalidate.
*/
void flush_tlb_page(struct vm_area_struct *vma, unsigned long va)
{
struct mm_struct *mm = vma->vm_mm;
cpumask_t cpu_mask;
preempt_disable();
cpu_mask = mm->cpu_vm_mask;
cpu_clear(smp_processor_id(), cpu_mask);
local_flush_tlb_page(mm, va);
if (!cpus_empty(cpu_mask))
flush_tlb_others(cpu_mask, mm, va);
preempt_enable();
}
/**
* do_flush_tlb_all - Callback to completely invalidate a TLB
* @unused: Callback context (ignored).
*/
static void do_flush_tlb_all(void *unused)
{
local_flush_tlb_all();
}
/**
* flush_tlb_all - Completely invalidate TLBs on all CPUs
*/
void flush_tlb_all(void)
{
on_each_cpu(do_flush_tlb_all, 0, 1);
}