These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / mm / swap_state.c

diff --git a/kernel/mm/swap_state.c b/kernel/mm/swap_state.c
index 8bc8e66..d504adb 100644 (file)
--- a/kernel/mm/swap_state.c
+++ b/kernel/mm/swap_state.c
@@ -288,17 +288,14 @@ struct page * lookup_swap_cache(swp_entry_t entry)
        return page;
 }
 
-/* 
- * Locate a page of swap in physical memory, reserving swap cache space
- * and reading the disk if it is not already cached.
- * A failure return means that either the page allocation failed or that
- * the swap entry is no longer in use.
- */
-struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
-                       struct vm_area_struct *vma, unsigned long addr)
+struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
+                       struct vm_area_struct *vma, unsigned long addr,
+                       bool *new_page_allocated)
 {
        struct page *found_page, *new_page = NULL;
+       struct address_space *swapper_space = swap_address_space(entry);
        int err;
+       *new_page_allocated = false;
 
        do {
                /*
@@ -306,8 +303,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
                 * called after lookup_swap_cache() failed, re-calling
                 * that would confuse statistics.
                 */
-               found_page = find_get_page(swap_address_space(entry),
-                                       entry.val);
+               found_page = find_get_page(swapper_space, entry.val);
                if (found_page)
                        break;
 
@@ -366,7 +362,7 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
                         * Initiate read into locked page and return.
                         */
                        lru_cache_add_anon(new_page);
-                       swap_readpage(new_page);
+                       *new_page_allocated = true;
                        return new_page;
                }
                radix_tree_preload_end();
@@ -384,6 +380,25 @@ struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
        return found_page;
 }
 
+/*
+ * Locate a page of swap in physical memory, reserving swap cache space
+ * and reading the disk if it is not already cached.
+ * A failure return means that either the page allocation failed or that
+ * the swap entry is no longer in use.
+ */
+struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
+                       struct vm_area_struct *vma, unsigned long addr)
+{
+       bool page_was_allocated;
+       struct page *retpage = __read_swap_cache_async(entry, gfp_mask,
+                       vma, addr, &page_was_allocated);
+
+       if (page_was_allocated)
+               swap_readpage(retpage);
+
+       return retpage;
+}
+
 static unsigned long swapin_nr_pages(unsigned long offset)
 {
        static unsigned long prev_offset;