From 965ea4bbb9ae926358273368144ba838c561bc38 Mon Sep 17 00:00:00 2001 From: Akira Takeuchi Date: Wed, 27 Oct 2010 17:28:51 +0100 Subject: 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 Signed-off-by: Kiyoshi Owada Signed-off-by: David Howells --- arch/mn10300/include/asm/mmu_context.h | 22 ++++ arch/mn10300/include/asm/tlbflush.h | 81 ++++++++----- arch/mn10300/mm/Makefile | 2 + arch/mn10300/mm/tlb-smp.c | 214 +++++++++++++++++++++++++++++++++ 4 files changed, 290 insertions(+), 29 deletions(-) create mode 100644 arch/mn10300/mm/tlb-smp.c (limited to 'arch') diff --git a/arch/mn10300/include/asm/mmu_context.h b/arch/mn10300/include/asm/mmu_context.h index 5fb3648968ae..c8f6c82672ad 100644 --- a/arch/mn10300/include/asm/mmu_context.h +++ b/arch/mn10300/include/asm/mmu_context.h @@ -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); } diff --git a/arch/mn10300/include/asm/tlbflush.h b/arch/mn10300/include/asm/tlbflush.h index c3c194d4031e..efddd6e1adea 100644 --- a/arch/mn10300/include/asm/tlbflush.h +++ b/arch/mn10300/include/asm/tlbflush.h @@ -11,6 +11,7 @@ #ifndef _ASM_TLBFLUSH_H #define _ASM_TLBFLUSH_H +#include #include 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) - -#define flush_tlb_mm(mm) \ -do { \ - preempt_disable(); \ - local_flush_tlb_all(); \ - preempt_enable(); \ -} while (0) - -#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) +#ifdef CONFIG_SMP + +#include + +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 */ diff --git a/arch/mn10300/mm/Makefile b/arch/mn10300/mm/Makefile index 184745f94c32..203fee23f7d7 100644 --- a/arch/mn10300/mm/Makefile +++ b/arch/mn10300/mm/Makefile @@ -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 diff --git a/arch/mn10300/mm/tlb-smp.c b/arch/mn10300/mm/tlb-smp.c new file mode 100644 index 000000000000..0b6a5ad1960e --- /dev/null +++ b/arch/mn10300/mm/tlb-smp.c @@ -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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * 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); +} -- cgit v1.2.1