mm, x86: Remove debug_pagealloc_enabled

When (no)bootmem finish operation, it pass pages to buddy
allocator. Since debug_pagealloc_enabled is not set, we will do
not protect pages, what is not what we want with
CONFIG_DEBUG_PAGEALLOC=y.

To fix remove debug_pagealloc_enabled. That variable was
introduced by commit 12d6f21e "x86: do not PSE on
CONFIG_DEBUG_PAGEALLOC=y" to get more CPA (change page
attribude) code testing. But currently we have CONFIG_CPA_DEBUG,
which test CPA.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1322582711-14571-1-git-send-email-sgruszka@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 0 insertions, 24 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index f9e526742fa1..5031eefa051f 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -1334,12 +1334,6 @@ void kernel_map_pages(struct page *page, int numpages, int enable)
         }
 
         /*
-         * If page allocator is not up yet then do not call c_p_a():
-         */
-        if (!debug_pagealloc_enabled)
-                return;
-
-        /*
          * The return value is ignored as the calls cannot fail.
          * Large pages for identity mappings are not used at boot time
          * and hence no memory allocations during large page split.
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3dc3a8c2c485..0a22db144753 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1537,23 +1537,13 @@ static inline void vm_stat_account(struct mm_struct *mm,
 #endif /* CONFIG_PROC_FS */
 
 #ifdef CONFIG_DEBUG_PAGEALLOC
-extern int debug_pagealloc_enabled;
-
 extern void kernel_map_pages(struct page *page, int numpages, int enable);
-
-static inline void enable_debug_pagealloc(void)
-{
-        debug_pagealloc_enabled = 1;
-}
 #ifdef CONFIG_HIBERNATION
 extern bool kernel_page_present(struct page *page);
 #endif /* CONFIG_HIBERNATION */
 #else
 static inline void
 kernel_map_pages(struct page *page, int numpages, int enable) {}
-static inline void enable_debug_pagealloc(void)
-{
-}
 #ifdef CONFIG_HIBERNATION
 static inline bool kernel_page_present(struct page *page) { return true; }
 #endif /* CONFIG_HIBERNATION */
diff --git a/init/main.c b/init/main.c
index 217ed23e9487..99c4ba30ba7e 100644
--- a/init/main.c
+++ b/init/main.c
@@ -282,10 +282,6 @@ static int __init unknown_bootoption(char *param, char *val)
         return 0;
 }
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-int __read_mostly debug_pagealloc_enabled = 0;
-#endif
-
 static int __init init_setup(char *str)
 {
         unsigned int i;
@@ -597,7 +593,6 @@ asmlinkage void __init start_kernel(void)
         }
 #endif
         page_cgroup_init();
-        enable_debug_pagealloc();
         debug_objects_mem_init();
         kmemleak_init();
         setup_per_cpu_pageset();
diff --git a/mm/debug-pagealloc.c b/mm/debug-pagealloc.c
index 7cea557407f4..789ff70c8a4a 100644
--- a/mm/debug-pagealloc.c
+++ b/mm/debug-pagealloc.c
@@ -95,9 +95,6 @@ static void unpoison_pages(struct page *page, int n)
 
 void kernel_map_pages(struct page *page, int numpages, int enable)
 {
-        if (!debug_pagealloc_enabled)
-                return;
-
         if (enable)
                 unpoison_pages(page, numpages);
         else