mm/hwpoison: introduce num_poisoned_pages wrappers

num_poisoned_pages counter will be changed outside mm/memory-failure.c
by a subsequent patch, so this patch prepares wrappers to manipulate it.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Tested-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index cedf3d3c373f167681424772c4fe2255e17b73fd..ec04669f2a3bf9e5a6180835b938a7e87c17586f 100644 (file)
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -164,6 +164,9 @@ static inline int is_write_migration_entry(swp_entry_t entry)
 #endif
 
 #ifdef CONFIG_MEMORY_FAILURE
+
+extern atomic_long_t num_poisoned_pages __read_mostly;
+
 /*
  * Support for hardware poisoned pages
  */
@@ -177,6 +180,26 @@ static inline int is_hwpoison_entry(swp_entry_t entry)
 {
        return swp_type(entry) == SWP_HWPOISON;
 }
+
+static inline void num_poisoned_pages_inc(void)
+{
+       atomic_long_inc(&num_poisoned_pages);
+}
+
+static inline void num_poisoned_pages_dec(void)
+{
+       atomic_long_dec(&num_poisoned_pages);
+}
+
+static inline void num_poisoned_pages_add(long num)
+{
+       atomic_long_add(num, &num_poisoned_pages);
+}
+
+static inline void num_poisoned_pages_sub(long num)
+{
+       atomic_long_sub(num, &num_poisoned_pages);
+}
 #else
 
 static inline swp_entry_t make_hwpoison_entry(struct page *page)

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 5420d3819adf99f224233895900868752d6a3a66..393ea13b07546e47b45292fccd95bec6e1a6fc66 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1121,7 +1121,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
                nr_pages = 1 << compound_order(hpage);
        else /* normal page or thp */
                nr_pages = 1;
-       atomic_long_add(nr_pages, &num_poisoned_pages);
+       num_poisoned_pages_add(nr_pages);
 
        /*
         * We need/can do nothing about count=0 pages.
@@ -1149,7 +1149,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
                        if (PageHWPoison(hpage)) {
                                if ((hwpoison_filter(p) && TestClearPageHWPoison(p))
                                    || (p != hpage && TestSetPageHWPoison(hpage))) {
-                                       atomic_long_sub(nr_pages, &num_poisoned_pages);
+                                       num_poisoned_pages_sub(nr_pages);
                                        unlock_page(hpage);
                                        return 0;
                                }
@@ -1173,7 +1173,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
                        else
                                pr_err("MCE: %#lx: thp split failed\n", pfn);
                        if (TestClearPageHWPoison(p))
-                               atomic_long_sub(nr_pages, &num_poisoned_pages);
+                               num_poisoned_pages_sub(nr_pages);
                        put_hwpoison_page(p);
                        return -EBUSY;
                }
@@ -1233,14 +1233,14 @@ int memory_failure(unsigned long pfn, int trapno, int flags)
         */
        if (!PageHWPoison(p)) {
                printk(KERN_ERR "MCE %#lx: just unpoisoned\n", pfn);
-               atomic_long_sub(nr_pages, &num_poisoned_pages);
+               num_poisoned_pages_sub(nr_pages);
                unlock_page(hpage);
                put_hwpoison_page(hpage);
                return 0;
        }
        if (hwpoison_filter(p)) {
                if (TestClearPageHWPoison(p))
-                       atomic_long_sub(nr_pages, &num_poisoned_pages);
+                       num_poisoned_pages_sub(nr_pages);
                unlock_page(hpage);
                put_hwpoison_page(hpage);
                return 0;
@@ -1469,7 +1469,7 @@ int unpoison_memory(unsigned long pfn)
                        return 0;
                }
                if (TestClearPageHWPoison(p))
-                       atomic_long_dec(&num_poisoned_pages);
+                       num_poisoned_pages_dec();
                pr_info("MCE: Software-unpoisoned free page %#lx\n", pfn);
                return 0;
        }
@@ -1483,7 +1483,7 @@ int unpoison_memory(unsigned long pfn)
         */
        if (TestClearPageHWPoison(page)) {
                pr_info("MCE: Software-unpoisoned page %#lx\n", pfn);
-               atomic_long_sub(nr_pages, &num_poisoned_pages);
+               num_poisoned_pages_sub(nr_pages);
                freeit = 1;
                if (PageHuge(page))
                        clear_page_hwpoison_huge_page(page);
@@ -1619,11 +1619,10 @@ static int soft_offline_huge_page(struct page *page, int flags)
                if (PageHuge(page)) {
                        set_page_hwpoison_huge_page(hpage);
                        dequeue_hwpoisoned_huge_page(hpage);
-                       atomic_long_add(1 << compound_order(hpage),
-                                       &num_poisoned_pages);
+                       num_poisoned_pages_add(1 << compound_order(hpage));
                } else {
                        SetPageHWPoison(page);
-                       atomic_long_inc(&num_poisoned_pages);
+                       num_poisoned_pages_inc();
                }
        }
        return ret;
@@ -1662,7 +1661,7 @@ static int __soft_offline_page(struct page *page, int flags)
                put_hwpoison_page(page);
                pr_info("soft_offline: %#lx: invalidated\n", pfn);
                SetPageHWPoison(page);
-               atomic_long_inc(&num_poisoned_pages);
+               num_poisoned_pages_inc();
                return 0;
        }
 
@@ -1683,7 +1682,7 @@ static int __soft_offline_page(struct page *page, int flags)
                                        page_is_file_cache(page));
                list_add(&page->lru, &pagelist);
                if (!TestSetPageHWPoison(page))
-                       atomic_long_inc(&num_poisoned_pages);
+                       num_poisoned_pages_dec();
                ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
                                        MIGRATE_SYNC, MR_MEMORY_FAILURE);
                if (ret) {
@@ -1699,7 +1698,7 @@ static int __soft_offline_page(struct page *page, int flags)
                        if (ret > 0)
                                ret = -EIO;
                        if (TestClearPageHWPoison(page))
-                               atomic_long_dec(&num_poisoned_pages);
+                               num_poisoned_pages_dec();
                }
        } else {
                pr_info("soft offline: %#lx: isolation failed: %d, page count %d, type %lx\n",
@@ -1765,11 +1764,10 @@ int soft_offline_page(struct page *page, int flags)
                if (PageHuge(page)) {
                        set_page_hwpoison_huge_page(hpage);
                        if (!dequeue_hwpoisoned_huge_page(hpage))
-                               atomic_long_add(1 << compound_order(hpage),
-                                       &num_poisoned_pages);
+                               num_poisoned_pages_add(1 << compound_order(hpage));
                } else {
                        if (!TestSetPageHWPoison(page))
-                               atomic_long_inc(&num_poisoned_pages);
+                               num_poisoned_pages_inc();
                }
        }
        return ret;