From 7de6b8057976584e5a422574cae4dd21c677b4d4 Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 22 Dec 2006 01:09:33 -0800 Subject: [PATCH] mm: more rmap debugging Add more debugging in the rmap code in an attempt to locate to source of the occasional "mapcount went negative" assertions. Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/rmap.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'mm/rmap.c') diff --git a/mm/rmap.c b/mm/rmap.c index d8a842a586d..b3deda8b501 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -47,6 +47,7 @@ #include #include #include +#include #include @@ -567,14 +568,20 @@ void page_add_file_rmap(struct page *page) * * The caller needs to hold the pte lock. */ -void page_remove_rmap(struct page *page) +void page_remove_rmap(struct page *page, struct vm_area_struct *vma) { if (atomic_add_negative(-1, &page->_mapcount)) { if (unlikely(page_mapcount(page) < 0)) { printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page)); + printk (KERN_EMERG " page pfn = %lx\n", page_to_pfn(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); + print_symbol (KERN_EMERG " vma->vm_ops = %s\n", (unsigned long)vma->vm_ops); + if (vma->vm_ops) + print_symbol (KERN_EMERG " vma->vm_ops->nopage = %s\n", (unsigned long)vma->vm_ops->nopage); + if (vma->vm_file && vma->vm_file->f_op) + print_symbol (KERN_EMERG " vma->vm_file->f_op->mmap = %s\n", (unsigned long)vma->vm_file->f_op->mmap); BUG(); } @@ -679,7 +686,7 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, dec_mm_counter(mm, file_rss); - page_remove_rmap(page); + page_remove_rmap(page, vma); page_cache_release(page); out_unmap: @@ -769,7 +776,7 @@ static void try_to_unmap_cluster(unsigned long cursor, if (pte_dirty(pteval)) set_page_dirty(page); - page_remove_rmap(page); + page_remove_rmap(page, vma); page_cache_release(page); dec_mm_counter(mm, file_rss); (*mapcount)--; -- cgit v1.2.3-18-g5258