Commit b7ab795b authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Linus Torvalds
Browse files

[PATCH] mm: more CONFIG_DEBUG_VM 



Put a few more checks under CONFIG_DEBUG_VM

Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 6626c5d5

mm/memory.c

+3 −9
Original line number Diff line number Diff line
@@ -388,7 +388,7 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, pte_ 
{

	unsigned long pfn = pte_pfn(pte);



	if (vma->vm_flags & VM_PFNMAP) {

	if (unlikely(vma->vm_flags & VM_PFNMAP)) {

		unsigned long off = (addr - vma->vm_start) >> PAGE_SHIFT;

		if (pfn == vma->vm_pgoff + off)

			return NULL;
@@ -396,18 +396,12 @@ struct page *vm_normal_page(struct vm_area_struct *vma, unsigned long addr, pte_ 
			return NULL;

	}



	/*

	 * Add some anal sanity checks for now. Eventually,

	 * we should just do "return pfn_to_page(pfn)", but

	 * in the meantime we check that we get a valid pfn,

	 * and that the resulting page looks ok.

	 *

	 * Remove this test eventually!

	 */

#ifdef CONFIG_DEBUG_VM

	if (unlikely(!pfn_valid(pfn))) {

		print_bad_pte(vma, pte, addr);

		return NULL;

	}

#endif



	/*

	 * NOTE! We still have PageReserved() pages in the page

mm/rmap.c

+4 −5
Original line number Diff line number Diff line
@@ -56,13 +56,11 @@ 


#include <asm/tlbflush.h>



//#define RMAP_DEBUG /* can be enabled only for debugging */



struct kmem_cache *anon_vma_cachep;



static inline void validate_anon_vma(struct vm_area_struct *find_vma)

{

#ifdef RMAP_DEBUG

#ifdef CONFIG_DEBUG_VM

	struct anon_vma *anon_vma = find_vma->anon_vma;

	struct vm_area_struct *vma;

	unsigned int mapcount = 0;
@@ -551,13 +549,14 @@ void page_add_file_rmap(struct page *page) 
void page_remove_rmap(struct page *page)

{

	if (atomic_add_negative(-1, &page->_mapcount)) {

		if (page_mapcount(page) < 0) {

#ifdef CONFIG_DEBUG_VM

		if (unlikely(page_mapcount(page) < 0)) {

			printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page));

			printk (KERN_EMERG "  page->flags = %lx\n", page->flags);

			printk (KERN_EMERG "  page->count = %x\n", page_count(page));

			printk (KERN_EMERG "  page->mapping = %p\n", page->mapping);

		}



#endif

		BUG_ON(page_mapcount(page) < 0);

		/*

		 * It would be tidy to reset the PageAnon mapping here,