mm: soft-offline: clean up soft_offline_page()

soft_offline_page() has some deeply indented code, that's the sign of
demand for cleanup.  So let's do this.  No functionality change.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1b99403..2015c9a 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1684,6 +1684,49 @@ static int __soft_offline_page(struct page *page, int flags)
        return ret;
 }
 
+static int soft_offline_in_use_page(struct page *page, int flags)
+{
+       int ret;
+       struct page *hpage = compound_head(page);
+
+       if (!PageHuge(page) && PageTransHuge(hpage)) {
+               lock_page(hpage);
+               ret = split_huge_page(hpage);
+               unlock_page(hpage);
+               if (unlikely(ret || PageTransCompound(page) ||
+                            !PageAnon(page))) {
+                       pr_info("soft offline: %#lx: failed to split THP\n",
+                               page_to_pfn(page));
+                       if (flags & MF_COUNT_INCREASED)
+                               put_hwpoison_page(hpage);
+                       return -EBUSY;
+               }
+               get_hwpoison_page(page);
+               put_hwpoison_page(hpage);
+       }
+
+       if (PageHuge(page))
+               ret = soft_offline_huge_page(page, flags);
+       else
+               ret = __soft_offline_page(page, flags);
+
+       return ret;
+}
+
+static void soft_offline_free_page(struct page *page)
+{
+       if (PageHuge(page)) {
+               struct page *hpage = compound_head(page);
+
+               set_page_hwpoison_huge_page(hpage);
+               if (!dequeue_hwpoisoned_huge_page(hpage))
+                       num_poisoned_pages_add(1 << compound_order(hpage));
+       } else {
+               if (!TestSetPageHWPoison(page))
+                       num_poisoned_pages_inc();
+       }
+}
+
 /**
  * soft_offline_page - Soft offline a page.
  * @page: page to offline
@@ -1710,7 +1753,6 @@ int soft_offline_page(struct page *page, int flags)
 {
        int ret;
        unsigned long pfn = page_to_pfn(page);
-       struct page *hpage = compound_head(page);
 
        if (PageHWPoison(page)) {
                pr_info("soft offline: %#lx page already poisoned\n", pfn);
@@ -1723,36 +1765,10 @@ int soft_offline_page(struct page *page, int flags)
        ret = get_any_page(page, pfn, flags);
        put_online_mems();
 
-       if (ret > 0) { /* for in-use pages */
-               if (!PageHuge(page) && PageTransHuge(hpage)) {
-                       lock_page(hpage);
-                       ret = split_huge_page(hpage);
-                       unlock_page(hpage);
-                       if (unlikely(ret || PageTransCompound(page) ||
-                                       !PageAnon(page))) {
-                               pr_info("soft offline: %#lx: failed to split THP\n",
-                                       pfn);
-                               if (flags & MF_COUNT_INCREASED)
-                                       put_hwpoison_page(hpage);
-                               return -EBUSY;
-                       }
-                       get_hwpoison_page(page);
-                       put_hwpoison_page(hpage);
-               }
+       if (ret > 0)
+               ret = soft_offline_in_use_page(page, flags);
+       else if (ret == 0)
+               soft_offline_free_page(page);
 
-               if (PageHuge(page))
-                       ret = soft_offline_huge_page(page, flags);
-               else
-                       ret = __soft_offline_page(page, flags);
-       } else if (ret == 0) { /* for free pages */
-               if (PageHuge(page)) {
-                       set_page_hwpoison_huge_page(hpage);
-                       if (!dequeue_hwpoisoned_huge_page(hpage))
-                               num_poisoned_pages_add(1 << compound_order(hpage));
-               } else {
-                       if (!TestSetPageHWPoison(page))
-                               num_poisoned_pages_inc();
-               }
-       }
        return ret;
 }