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>

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index f9e5267..5031eef 100644 (file)
--- 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 3dc3a8c..0a22db1 100644 (file)
--- 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 217ed23..99c4ba3 100644 (file)
--- 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 7cea557..789ff70 100644 (file)
--- 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