mm, vmscan: get rid of throttle_vm_writeout

[cascardo/linux.git] / mm / page_poison.c

diff --git a/mm/page_poison.c b/mm/page_poison.c
index 479e7ea..2e647c6 100644 (file)
--- a/mm/page_poison.c
+++ b/mm/page_poison.c
@@ -13,13 +13,7 @@ static int early_page_poison_param(char *buf)
 {
        if (!buf)
                return -EINVAL;
-
-       if (strcmp(buf, "on") == 0)
-               want_page_poisoning = true;
-       else if (strcmp(buf, "off") == 0)
-               want_page_poisoning = false;
-
-       return 0;
+       return strtobool(buf, &want_page_poisoning);
 }
 early_param("page_poison", early_page_poison_param);
 
@@ -60,6 +54,9 @@ static inline void set_page_poison(struct page *page)
        struct page_ext *page_ext;
 
        page_ext = lookup_page_ext(page);
+       if (unlikely(!page_ext))
+               return;
+
        __set_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
 }
 
@@ -68,6 +65,9 @@ static inline void clear_page_poison(struct page *page)
        struct page_ext *page_ext;
 
        page_ext = lookup_page_ext(page);
+       if (unlikely(!page_ext))
+               return;
+
        __clear_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);
 }
 
@@ -76,7 +76,7 @@ bool page_is_poisoned(struct page *page)
        struct page_ext *page_ext;
 
        page_ext = lookup_page_ext(page);
-       if (!page_ext)
+       if (unlikely(!page_ext))
                return false;
 
        return test_bit(PAGE_EXT_DEBUG_POISON, &page_ext->flags);