hugetlb: move hugetlb_acct_memory()

[sfrench/cifs-2.6.git] / mm / hugetlb.c

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index bbf953eeb58bafbad0016a6f73db4844e5514c22..a4dbba8965f3a19abb88b356e3da4b8f61d26895 100644 (file)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -603,7 +603,6 @@ static unsigned long set_max_huge_pages(unsigned long count)
        }
 
        while (count > persistent_huge_pages) {
-               int ret;
                /*
                 * If this allocation races such that we no longer need the
                 * page, free_huge_page will handle it by freeing the page
@@ -717,6 +716,47 @@ unsigned long hugetlb_total_pages(void)
        return nr_huge_pages * (HPAGE_SIZE / PAGE_SIZE);
 }
 
+static int hugetlb_acct_memory(long delta)
+{
+       int ret = -ENOMEM;
+
+       spin_lock(&hugetlb_lock);
+       /*
+        * When cpuset is configured, it breaks the strict hugetlb page
+        * reservation as the accounting is done on a global variable. Such
+        * reservation is completely rubbish in the presence of cpuset because
+        * the reservation is not checked against page availability for the
+        * current cpuset. Application can still potentially OOM'ed by kernel
+        * with lack of free htlb page in cpuset that the task is in.
+        * Attempt to enforce strict accounting with cpuset is almost
+        * impossible (or too ugly) because cpuset is too fluid that
+        * task or memory node can be dynamically moved between cpusets.
+        *
+        * The change of semantics for shared hugetlb mapping with cpuset is
+        * undesirable. However, in order to preserve some of the semantics,
+        * we fall back to check against current free page availability as
+        * a best attempt and hopefully to minimize the impact of changing
+        * semantics that cpuset has.
+        */
+       if (delta > 0) {
+               if (gather_surplus_pages(delta) < 0)
+                       goto out;
+
+               if (delta > cpuset_mems_nr(free_huge_pages_node)) {
+                       return_unused_surplus_pages(delta);
+                       goto out;
+               }
+       }
+
+       ret = 0;
+       if (delta < 0)
+               return_unused_surplus_pages((unsigned long) -delta);
+
+out:
+       spin_unlock(&hugetlb_lock);
+       return ret;
+}
+
 /*
  * We cannot handle pagefaults against hugetlb pages at all.  They cause
  * handle_mm_fault() to try to instantiate regular-sized pages in the
@@ -785,7 +825,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
                        continue;
 
                spin_lock(&dst->page_table_lock);
-               spin_lock(&src->page_table_lock);
+               spin_lock_nested(&src->page_table_lock, SINGLE_DEPTH_NESTING);
                if (!huge_pte_none(huge_ptep_get(src_pte))) {
                        if (cow)
                                huge_ptep_set_wrprotect(src, addr, src_pte);
@@ -1249,47 +1289,6 @@ static long region_truncate(struct list_head *head, long end)
        return chg;
 }
 
-static int hugetlb_acct_memory(long delta)
-{
-       int ret = -ENOMEM;
-
-       spin_lock(&hugetlb_lock);
-       /*
-        * When cpuset is configured, it breaks the strict hugetlb page
-        * reservation as the accounting is done on a global variable. Such
-        * reservation is completely rubbish in the presence of cpuset because
-        * the reservation is not checked against page availability for the
-        * current cpuset. Application can still potentially OOM'ed by kernel
-        * with lack of free htlb page in cpuset that the task is in.
-        * Attempt to enforce strict accounting with cpuset is almost
-        * impossible (or too ugly) because cpuset is too fluid that
-        * task or memory node can be dynamically moved between cpusets.
-        *
-        * The change of semantics for shared hugetlb mapping with cpuset is
-        * undesirable. However, in order to preserve some of the semantics,
-        * we fall back to check against current free page availability as
-        * a best attempt and hopefully to minimize the impact of changing
-        * semantics that cpuset has.
-        */
-       if (delta > 0) {
-               if (gather_surplus_pages(delta) < 0)
-                       goto out;
-
-               if (delta > cpuset_mems_nr(free_huge_pages_node)) {
-                       return_unused_surplus_pages(delta);
-                       goto out;
-               }
-       }
-
-       ret = 0;
-       if (delta < 0)
-               return_unused_surplus_pages((unsigned long) -delta);
-
-out:
-       spin_unlock(&hugetlb_lock);
-       return ret;
-}
-
 int hugetlb_reserve_pages(struct inode *inode, long from, long to)
 {
        long ret, chg;