CRIS v10: Don't call get_mmu_context when switching between tasks with shared memory descriptors
Also, cleanup formatting and fix whitespace errors.
diff --git a/arch/cris/arch-v10/mm/tlb.c b/arch/cris/arch-v10/mm/tlb.c
index 7d9fec8..6baf5bd 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 @@
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 @@
*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 @@
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 @@
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 @@
/* 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 @@
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 @@
(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 @@
{
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 @@
/* 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);
+ }
}