x86, pat: Update the page flags for memtype atomically instead of using memtype_lock

[net-next-2.6.git] / arch / x86 / mm / pat.c

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 951011166ef5bfbf9ea6b925f31dbd0ef89af29e..501fc60e5e4d76c341e01b53a30083caeed56bf4 100644 (file)
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -190,8 +190,6 @@ static int pat_pagerange_is_ram(unsigned long start, unsigned long end)
  * Here we do two pass:
  * - Find the memtype of all the pages in the range, look for any conflicts
  * - In case of no conflicts, set the new memtype for pages in the range
- *
- * Caller must hold memtype_lock for atomicity.
  */
 static int reserve_ram_pages_type(u64 start, u64 end, unsigned long req_type,
                                  unsigned long *new_type)
@@ -297,9 +295,7 @@ int reserve_memtype(u64 start, u64 end, unsigned long req_type,
        is_range_ram = pat_pagerange_is_ram(start, end);
        if (is_range_ram == 1) {
 
-               spin_lock(&memtype_lock);
                err = reserve_ram_pages_type(start, end, req_type, new_type);
-               spin_unlock(&memtype_lock);
 
                return err;
        } else if (is_range_ram < 0) {
@@ -351,9 +347,7 @@ int free_memtype(u64 start, u64 end)
        is_range_ram = pat_pagerange_is_ram(start, end);
        if (is_range_ram == 1) {
 
-               spin_lock(&memtype_lock);
                err = free_ram_pages_type(start, end);
-               spin_unlock(&memtype_lock);
 
                return err;
        } else if (is_range_ram < 0) {
@@ -394,10 +388,8 @@ static unsigned long lookup_memtype(u64 paddr)
 
        if (pat_pagerange_is_ram(paddr, paddr + PAGE_SIZE)) {
                struct page *page;
-               spin_lock(&memtype_lock);
                page = pfn_to_page(paddr >> PAGE_SHIFT);
                rettype = get_page_memtype(page);
-               spin_unlock(&memtype_lock);
                /*
                 * -1 from get_page_memtype() implies RAM page is in its
                 * default state and not reserved, and hence of type WB