From 4f073eff3fb738dce5ad0d8a3d126e5c09cbfba7 Mon Sep 17 00:00:00 2001 From: Jesper Nilsson Date: Mon, 21 Jan 2008 11:28:16 +0100 Subject: CRIS v10: Don't call get_mmu_context when switching between tasks with shared memory descriptors Also, cleanup formatting and fix whitespace errors. --- arch/cris/arch-v10/mm/tlb.c | 58 ++++++++++++++++++++++----------------------- 1 file changed, 29 insertions(+), 29 deletions(-) (limited to 'arch') diff --git a/arch/cris/arch-v10/mm/tlb.c b/arch/cris/arch-v10/mm/tlb.c index 7d9fec88dee..6baf5bd209e 100644 --- a/arch/cris/arch-v10/mm/tlb.c +++ b/arch/cris/arch-v10/mm/tlb.c @@ -4,8 +4,8 @@ * Low level TLB handling * * - * Copyright (C) 2000-2002 Axis Communications AB - * + * Copyright (C) 2000-2007 Axis Communications AB + * * Authors: Bjorn Wesen (bjornw@axis.com) * */ @@ -39,7 +39,7 @@ flush_tlb_all(void) unsigned long flags; /* the vpn of i & 0xf is so we dont write similar TLB entries - * in the same 4-way entry group. details.. + * in the same 4-way entry group. details... */ local_irq_save(flags); @@ -47,7 +47,7 @@ flush_tlb_all(void) *R_TLB_SELECT = ( IO_FIELD(R_TLB_SELECT, index, i) ); *R_TLB_HI = ( IO_FIELD(R_TLB_HI, page_id, INVALID_PAGEID ) | IO_FIELD(R_TLB_HI, vpn, i & 0xf ) ); - + *R_TLB_LO = ( IO_STATE(R_TLB_LO, global,no ) | IO_STATE(R_TLB_LO, valid, no ) | IO_STATE(R_TLB_LO, kernel,no ) | @@ -71,10 +71,10 @@ flush_tlb_mm(struct mm_struct *mm) if(page_id == NO_CONTEXT) return; - + /* mark the TLB entries that match the page_id as invalid. * here we could also check the _PAGE_GLOBAL bit and NOT flush - * global pages. is it worth the extra I/O ? + * global pages. is it worth the extra I/O ? */ local_irq_save(flags); @@ -83,7 +83,7 @@ flush_tlb_mm(struct mm_struct *mm) if (IO_EXTRACT(R_TLB_HI, page_id, *R_TLB_HI) == page_id) { *R_TLB_HI = ( IO_FIELD(R_TLB_HI, page_id, INVALID_PAGEID ) | IO_FIELD(R_TLB_HI, vpn, i & 0xf ) ); - + *R_TLB_LO = ( IO_STATE(R_TLB_LO, global,no ) | IO_STATE(R_TLB_LO, valid, no ) | IO_STATE(R_TLB_LO, kernel,no ) | @@ -96,9 +96,7 @@ flush_tlb_mm(struct mm_struct *mm) /* invalidate a single page */ -void -flush_tlb_page(struct vm_area_struct *vma, - unsigned long addr) +void flush_tlb_page(struct vm_area_struct *vma, unsigned long addr) { struct mm_struct *mm = vma->vm_mm; int page_id = mm->context.page_id; @@ -113,7 +111,7 @@ flush_tlb_page(struct vm_area_struct *vma, addr &= PAGE_MASK; /* perhaps not necessary */ /* invalidate those TLB entries that match both the mm context - * and the virtual address requested + * and the virtual address requested */ local_irq_save(flags); @@ -125,7 +123,7 @@ flush_tlb_page(struct vm_area_struct *vma, (tlb_hi & PAGE_MASK) == addr) { *R_TLB_HI = IO_FIELD(R_TLB_HI, page_id, INVALID_PAGEID ) | addr; /* same addr as before works. */ - + *R_TLB_LO = ( IO_STATE(R_TLB_LO, global,no ) | IO_STATE(R_TLB_LO, valid, no ) | IO_STATE(R_TLB_LO, kernel,no ) | @@ -144,7 +142,7 @@ dump_tlb_all(void) { int i; unsigned long flags; - + printk("TLB dump. LO is: pfn | reserved | global | valid | kernel | we |\n"); local_save_flags(flags); @@ -172,27 +170,29 @@ init_new_context(struct task_struct *tsk, struct mm_struct *mm) /* called in schedule() just before actually doing the switch_to */ -void -switch_mm(struct mm_struct *prev, struct mm_struct *next, - struct task_struct *tsk) +void switch_mm(struct mm_struct *prev, struct mm_struct *next, + struct task_struct *tsk) { - /* make sure we have a context */ + if (prev != next) { + /* make sure we have a context */ + get_mmu_context(next); - get_mmu_context(next); + /* remember the pgd for the fault handlers + * this is similar to the pgd register in some other CPU's. + * we need our own copy of it because current and active_mm + * might be invalid at points where we still need to derefer + * the pgd. + */ - /* remember the pgd for the fault handlers - * this is similar to the pgd register in some other CPU's. - * we need our own copy of it because current and active_mm - * might be invalid at points where we still need to derefer - * the pgd. - */ + per_cpu(current_pgd, smp_processor_id()) = next->pgd; - per_cpu(current_pgd, smp_processor_id()) = next->pgd; + /* switch context in the MMU */ - /* switch context in the MMU */ - - D(printk("switching mmu_context to %d (%p)\n", next->context, next)); + D(printk(KERN_DEBUG "switching mmu_context to %d (%p)\n", + next->context, next)); - *R_MMU_CONTEXT = IO_FIELD(R_MMU_CONTEXT, page_id, next->context.page_id); + *R_MMU_CONTEXT = IO_FIELD(R_MMU_CONTEXT, + page_id, next->context.page_id); + } } -- cgit v1.2.3