diff options
Diffstat (limited to 'include/asm-ia64/mmu_context.h')
| -rw-r--r-- | include/asm-ia64/mmu_context.h | 173 |
1 files changed, 0 insertions, 173 deletions
diff --git a/include/asm-ia64/mmu_context.h b/include/asm-ia64/mmu_context.h deleted file mode 100644 index e3e5fededb0..00000000000 --- a/include/asm-ia64/mmu_context.h +++ /dev/null @@ -1,173 +0,0 @@ -#ifndef _ASM_IA64_MMU_CONTEXT_H -#define _ASM_IA64_MMU_CONTEXT_H - -/* - * Copyright (C) 1998-2002 Hewlett-Packard Co - * David Mosberger-Tang <davidm@hpl.hp.com> - */ - -/* - * Routines to manage the allocation of task context numbers. Task context numbers are - * used to reduce or eliminate the need to perform TLB flushes due to context switches. - * Context numbers are implemented using ia-64 region ids. Since the IA-64 TLB does not - * consider the region number when performing a TLB lookup, we need to assign a unique - * region id to each region in a process. We use the least significant three bits in a - * region id for this purpose. - */ - -#define IA64_REGION_ID_KERNEL 0 /* the kernel's region id (tlb.c depends on this being 0) */ - -#define ia64_rid(ctx,addr) (((ctx) << 3) | (addr >> 61)) - -# ifndef __ASSEMBLY__ - -#include <linux/compiler.h> -#include <linux/percpu.h> -#include <linux/sched.h> -#include <linux/spinlock.h> - -#include <asm/processor.h> - -struct ia64_ctx { - spinlock_t lock; - unsigned int next; /* next context number to use */ - unsigned int limit; /* next >= limit => must call wrap_mmu_context() */ - unsigned int max_ctx; /* max. context value supported by all CPUs */ -}; - -extern struct ia64_ctx ia64_ctx; -DECLARE_PER_CPU(u8, ia64_need_tlb_flush); - -extern void wrap_mmu_context (struct mm_struct *mm); - -static inline void -enter_lazy_tlb (struct mm_struct *mm, struct task_struct *tsk) -{ -} - -/* - * When the context counter wraps around all TLBs need to be flushed because an old - * context number might have been reused. This is signalled by the ia64_need_tlb_flush - * per-CPU variable, which is checked in the routine below. Called by activate_mm(). - * <efocht@ess.nec.de> - */ -static inline void -delayed_tlb_flush (void) -{ - extern void local_flush_tlb_all (void); - - if (unlikely(__ia64_per_cpu_var(ia64_need_tlb_flush))) { - local_flush_tlb_all(); - __ia64_per_cpu_var(ia64_need_tlb_flush) = 0; - } -} - -static inline mm_context_t -get_mmu_context (struct mm_struct *mm) -{ - unsigned long flags; - mm_context_t context = mm->context; - - if (context) - return context; - - spin_lock_irqsave(&ia64_ctx.lock, flags); - { - /* re-check, now that we've got the lock: */ - context = mm->context; - if (context == 0) { - cpus_clear(mm->cpu_vm_mask); - if (ia64_ctx.next >= ia64_ctx.limit) - wrap_mmu_context(mm); - mm->context = context = ia64_ctx.next++; - } - } - spin_unlock_irqrestore(&ia64_ctx.lock, flags); - return context; -} - -/* - * Initialize context number to some sane value. MM is guaranteed to be a brand-new - * address-space, so no TLB flushing is needed, ever. - */ -static inline int -init_new_context (struct task_struct *p, struct mm_struct *mm) -{ - mm->context = 0; - return 0; -} - -static inline void -destroy_context (struct mm_struct *mm) -{ - /* Nothing to do. */ -} - -static inline void -reload_context (mm_context_t context) -{ - unsigned long rid; - unsigned long rid_incr = 0; - unsigned long rr0, rr1, rr2, rr3, rr4, old_rr4; - - old_rr4 = ia64_get_rr(0x8000000000000000UL); - rid = context << 3; /* make space for encoding the region number */ - rid_incr = 1 << 8; - - /* encode the region id, preferred page size, and VHPT enable bit: */ - rr0 = (rid << 8) | (PAGE_SHIFT << 2) | 1; - rr1 = rr0 + 1*rid_incr; - rr2 = rr0 + 2*rid_incr; - rr3 = rr0 + 3*rid_incr; - rr4 = rr0 + 4*rid_incr; -#ifdef CONFIG_HUGETLB_PAGE - rr4 = (rr4 & (~(0xfcUL))) | (old_rr4 & 0xfc); -#endif - - ia64_set_rr(0x0000000000000000UL, rr0); - ia64_set_rr(0x2000000000000000UL, rr1); - ia64_set_rr(0x4000000000000000UL, rr2); - ia64_set_rr(0x6000000000000000UL, rr3); - ia64_set_rr(0x8000000000000000UL, rr4); - ia64_srlz_i(); /* srlz.i implies srlz.d */ -} - -/* - * Must be called with preemption off - */ -static inline void -activate_context (struct mm_struct *mm) -{ - mm_context_t context; - - do { - context = get_mmu_context(mm); - if (!cpu_isset(smp_processor_id(), mm->cpu_vm_mask)) - cpu_set(smp_processor_id(), mm->cpu_vm_mask); - reload_context(context); - /* in the unlikely event of a TLB-flush by another thread, redo the load: */ - } while (unlikely(context != mm->context)); -} - -#define deactivate_mm(tsk,mm) do { } while (0) - -/* - * Switch from address space PREV to address space NEXT. - */ -static inline void -activate_mm (struct mm_struct *prev, struct mm_struct *next) -{ - delayed_tlb_flush(); - - /* - * We may get interrupts here, but that's OK because interrupt handlers cannot - * touch user-space. - */ - ia64_set_kr(IA64_KR_PT_BASE, __pa(next->pgd)); - activate_context(next); -} - -#define switch_mm(prev_mm,next_mm,next_task) activate_mm(prev_mm, next_mm) - -# endif /* ! __ASSEMBLY__ */ -#endif /* _ASM_IA64_MMU_CONTEXT_H */ |