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

@@ -4,7 +4,7 @@
  *  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);
@@ -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;
@@ -172,12 +170,11 @@ 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,
+void switch_mm(struct mm_struct *prev, struct mm_struct *next,
 	struct task_struct *tsk)
 {
+	if (prev != next) {
 		/* make sure we have a context */
-
 		get_mmu_context(next);
 
 		/* remember the pgd for the fault handlers
@@ -191,8 +188,11 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next,
 
 		/* 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);
+	}
 }