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>

1 files changed, 47 insertions, 31 deletions

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1b99403d76f2..2015c9a06cae 100644
--- 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;
 }