x86: do not PSE on CONFIG_DEBUG_PAGEALLOC=y

get more testing of the c_p_a() code done by not turning off
PSE on DEBUG_PAGEALLOC.

this simplifies the early pagetable setup code, and tests
the largepage-splitup code quite heavily.

In the end, all the largepages will be split up pretty quickly,
so there's no difference to how DEBUG_PAGEALLOC worked before.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 13 insertions, 6 deletions

diff --git a/include/asm-x86/cacheflush.h b/include/asm-x86/cacheflush.h
index 9411a2d3f19c..fccb563e2305 100644
--- a/include/asm-x86/cacheflush.h
+++ b/include/asm-x86/cacheflush.h
@@ -29,11 +29,6 @@ int change_page_attr(struct page *page, int numpages, pgprot_t prot);
 int change_page_attr_addr(unsigned long addr, int numpages, pgprot_t prot);
 void clflush_cache_range(void *addr, int size);
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
-/* internal debugging function */
-void kernel_map_pages(struct page *page, int numpages, int enable);
-#endif
-
 #ifdef CONFIG_DEBUG_RODATA
 void mark_rodata_ro(void);
 #endif
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 3c22d971afa7..1bba6789a50a 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1118,9 +1118,21 @@ static inline void vm_stat_account(struct mm_struct *mm,
 }
 #endif /* CONFIG_PROC_FS */
 
-#ifndef CONFIG_DEBUG_PAGEALLOC
+#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;
+}
+#else
 static inline void
 kernel_map_pages(struct page *page, int numpages, int enable) {}
+static inline void enable_debug_pagealloc(void)
+{
+}
 #endif
 
 extern struct vm_area_struct *get_gate_vma(struct task_struct *tsk);