[SPARC64]: Avoid dcache-dirty page state management on sun4v.

It is totally wasted work, since we have no D-cache aliasing
issues on sun4v.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 30 insertions, 23 deletions

diff --git a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
index ccf083aecb65..87d5d1af1adb 100644
--- a/arch/sparc64/mm/init.c
+++ b/arch/sparc64/mm/init.c
@@ -188,8 +188,9 @@ atomic_t dcpage_flushes_xcall = ATOMIC_INIT(0);
 #endif
 #endif
 
-__inline__ void flush_dcache_page_impl(struct page *page)
+inline void flush_dcache_page_impl(struct page *page)
 {
+        BUG_ON(tlb_type == hypervisor);
 #ifdef CONFIG_DEBUG_DCFLUSH
         atomic_inc(&dcpage_flushes);
 #endif
@@ -279,29 +280,31 @@ unsigned long _PAGE_SZBITS __read_mostly;
 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t pte)
 {
         struct mm_struct *mm;
-        struct page *page;
-        unsigned long pfn;
-        unsigned long pg_flags;
-
-        pfn = pte_pfn(pte);
-        if (pfn_valid(pfn) &&
-            (page = pfn_to_page(pfn), page_mapping(page)) &&
-            ((pg_flags = page->flags) & (1UL << PG_dcache_dirty))) {
-                int cpu = ((pg_flags >> PG_dcache_cpu_shift) &
-                           PG_dcache_cpu_mask);
-                int this_cpu = get_cpu();
-
-                /* This is just to optimize away some function calls
-                 * in the SMP case.
-                 */
-                if (cpu == this_cpu)
-                        flush_dcache_page_impl(page);
-                else
-                        smp_flush_dcache_page_impl(page, cpu);
 
-                clear_dcache_dirty_cpu(page, cpu);
+        if (tlb_type != hypervisor) {
+                unsigned long pfn = pte_pfn(pte);
+                unsigned long pg_flags;
+                struct page *page;
+
+                if (pfn_valid(pfn) &&
+                    (page = pfn_to_page(pfn), page_mapping(page)) &&
+                    ((pg_flags = page->flags) & (1UL << PG_dcache_dirty))) {
+                        int cpu = ((pg_flags >> PG_dcache_cpu_shift) &
+                                   PG_dcache_cpu_mask);
+                        int this_cpu = get_cpu();
+
+                        /* This is just to optimize away some function calls
+                         * in the SMP case.
+                         */
+                        if (cpu == this_cpu)
+                                flush_dcache_page_impl(page);
+                        else
+                                smp_flush_dcache_page_impl(page, cpu);
+
+                        clear_dcache_dirty_cpu(page, cpu);
 
-                put_cpu();
+                        put_cpu();
+                }
         }
 
         mm = vma->vm_mm;
@@ -321,6 +324,9 @@ void flush_dcache_page(struct page *page)
         struct address_space *mapping;
         int this_cpu;
 
+        if (tlb_type == hypervisor)
+                return;
+
         /* Do not bother with the expensive D-cache flush if it
          * is merely the zero page.  The 'bigcore' testcase in GDB
          * causes this case to run millions of times.
diff --git a/arch/sparc64/mm/tlb.c b/arch/sparc64/mm/tlb.c
index 78357cc2a0b7..a079cf42505e 100644
--- a/arch/sparc64/mm/tlb.c
+++ b/arch/sparc64/mm/tlb.c
@@ -49,7 +49,8 @@ void tlb_batch_add(struct mm_struct *mm, unsigned long vaddr, pte_t *ptep, pte_t
         if (pte_exec(orig))
                 vaddr |= 0x1UL;
 
-        if (pte_dirty(orig)) {
+        if (tlb_type != hypervisor &&
+            pte_dirty(orig)) {
                 unsigned long paddr, pfn = pte_pfn(orig);
                 struct address_space *mapping;
                 struct page *page;