mm: Some arch may want to use HPAGE_PMD related values as variables

[deliverable/linux.git] / mm / huge_memory.c

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index aea8f7a42df97d7185f626d5bbc445c64f376eb1..36c22a89df610032b50f275a0c92cd3c45e20d49 100644 (file)
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -83,7 +83,7 @@ unsigned long transparent_hugepage_flags __read_mostly =
        (1<<TRANSPARENT_HUGEPAGE_USE_ZERO_PAGE_FLAG);
 
 /* default scan 8*512 pte (or vmas) every 30 second */
-static unsigned int khugepaged_pages_to_scan __read_mostly = HPAGE_PMD_NR*8;
+static unsigned int khugepaged_pages_to_scan __read_mostly;
 static unsigned int khugepaged_pages_collapsed;
 static unsigned int khugepaged_full_scans;
 static unsigned int khugepaged_scan_sleep_millisecs __read_mostly = 10000;
@@ -98,7 +98,7 @@ static DECLARE_WAIT_QUEUE_HEAD(khugepaged_wait);
  * it would have happened if the vma was large enough during page
  * fault.
  */
-static unsigned int khugepaged_max_ptes_none __read_mostly = HPAGE_PMD_NR-1;
+static unsigned int khugepaged_max_ptes_none __read_mostly;
 
 static int khugepaged(void *none);
 static int khugepaged_slab_init(void);
@@ -660,6 +660,18 @@ static int __init hugepage_init(void)
                return -EINVAL;
        }
 
+       khugepaged_pages_to_scan = HPAGE_PMD_NR * 8;
+       khugepaged_max_ptes_none = HPAGE_PMD_NR - 1;
+       /*
+        * hugepages can't be allocated by the buddy allocator
+        */
+       MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER >= MAX_ORDER);
+       /*
+        * we use page->mapping and page->index in second tail page
+        * as list_head: assuming THP order >= 2
+        */
+       MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER < 2);
+
        err = hugepage_init_sysfs(&hugepage_kobj);
        if (err)
                goto err_sysfs;
@@ -764,7 +776,6 @@ void prep_transhuge_page(struct page *page)
         * we use page->mapping and page->indexlru in second tail page
         * as list_head: assuming THP order >= 2
         */
-       BUILD_BUG_ON(HPAGE_PMD_ORDER < 2);
 
        INIT_LIST_HEAD(page_deferred_list(page));
        set_compound_page_dtor(page, TRANSHUGE_PAGE_DTOR);