x86: have set_memory_array_{uc,wb} coalesce memtypes.

Actually, might as well simply reconstruct the memtype list at free time
I guess. How is this for a coalescing version of the array functions?

Compiles, boots and provides me with:

  root@7ixe4:~# wc -l /debug/x86/pat_memtype_list
  53 /debug/x86/pat_memtype_list

otherwise (down from 16384+).

Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index fed6ba2a8e7e77e0e63e4c956cb5400c28254e40..497108825da975b15d40e8a184f034710fb56ed1 100644 (file)
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -942,21 +942,38 @@ EXPORT_SYMBOL(set_memory_uc);
 
 int set_memory_array_uc(unsigned long *addr, int addrinarray)
 {
+       unsigned long start;
+       unsigned long end;
        int i;
        /*
         * for now UC MINUS. see comments in ioremap_nocache()
         */
        for (i = 0; i < addrinarray; i++) {
-               if (reserve_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE,
-                           _PAGE_CACHE_UC_MINUS, NULL))
+               start = __pa(addr[i]);
+               for (end = start + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) {
+                       if (end != __pa(addr[i + 1]))
+                               break;
+                       i++;
+               }
+               if (reserve_memtype(start, end, _PAGE_CACHE_UC_MINUS, NULL))
                        goto out;
        }
 
        return change_page_attr_set(addr, addrinarray,
                                    __pgprot(_PAGE_CACHE_UC_MINUS), 1);
 out:
-       while (--i >= 0)
-               free_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE);
+       for (i = 0; i < addrinarray; i++) {
+               unsigned long tmp = __pa(addr[i]);
+
+               if (tmp == start)
+                       break;
+               for (end = start + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) {
+                       if (end != __pa(addr[i + 1]))
+                               break;
+                       i++;
+               }
+               free_memtype(tmp, end);
+       }
        return -EINVAL;
 }
 EXPORT_SYMBOL(set_memory_array_uc);
@@ -997,9 +1014,18 @@ EXPORT_SYMBOL(set_memory_wb);
 int set_memory_array_wb(unsigned long *addr, int addrinarray)
 {
        int i;
-       for (i = 0; i < addrinarray; i++)
-               free_memtype(__pa(addr[i]), __pa(addr[i]) + PAGE_SIZE);
 
+       for (i = 0; i < addrinarray; i++) {
+               unsigned long start = __pa(addr[i]);
+               unsigned long end;
+
+               for (end = start + PAGE_SIZE; i < addrinarray - 1; end += PAGE_SIZE) {
+                       if (end != __pa(addr[i + 1]))
+                               break;
+                       i++;
+               }
+               free_memtype(start, end);
+       }
        return change_page_attr_clear(addr, addrinarray,
                                      __pgprot(_PAGE_CACHE_MASK), 1);
 }