From 309381feaee564281c3d9e90fbca8963bb7428ad Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Thu, 23 Jan 2014 15:52:54 -0800 Subject: mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE Most of the VM_BUG_ON assertions are performed on a page. Usually, when one of these assertions fails we'll get a BUG_ON with a call stack and the registers. I've recently noticed based on the requests to add a small piece of code that dumps the page to various VM_BUG_ON sites that the page dump is quite useful to people debugging issues in mm. This patch adds a VM_BUG_ON_PAGE(cond, page) which beyond doing what VM_BUG_ON() does, also dumps the page before executing the actual BUG_ON. [akpm@linux-foundation.org: fix up includes] Signed-off-by: Sasha Levin Cc: "Kirill A. Shutemov" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'mm/hugetlb.c') diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 04306b9de90d..c01cb9fedb18 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -584,7 +584,7 @@ static void update_and_free_page(struct hstate *h, struct page *page) 1 << PG_active | 1 << PG_reserved | 1 << PG_private | 1 << PG_writeback); } - VM_BUG_ON(hugetlb_cgroup_from_page(page)); + VM_BUG_ON_PAGE(hugetlb_cgroup_from_page(page), page); set_compound_page_dtor(page, NULL); set_page_refcounted(page); arch_release_hugepage(page); @@ -1089,7 +1089,7 @@ retry: * no users -- drop the buddy allocator's reference. */ put_page_testzero(page); - VM_BUG_ON(page_count(page)); + VM_BUG_ON_PAGE(page_count(page), page); enqueue_huge_page(h, page); } free: @@ -3503,7 +3503,7 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage) bool isolate_huge_page(struct page *page, struct list_head *list) { - VM_BUG_ON(!PageHead(page)); + VM_BUG_ON_PAGE(!PageHead(page), page); if (!get_page_unless_zero(page)) return false; spin_lock(&hugetlb_lock); @@ -3514,7 +3514,7 @@ bool isolate_huge_page(struct page *page, struct list_head *list) void putback_active_hugepage(struct page *page) { - VM_BUG_ON(!PageHead(page)); + VM_BUG_ON_PAGE(!PageHead(page), page); spin_lock(&hugetlb_lock); list_move_tail(&page->lru, &(page_hstate(page))->hugepage_activelist); spin_unlock(&hugetlb_lock); @@ -3523,7 +3523,7 @@ void putback_active_hugepage(struct page *page) bool is_hugepage_active(struct page *page) { - VM_BUG_ON(!PageHuge(page)); + VM_BUG_ON_PAGE(!PageHuge(page), page); /* * This function can be called for a tail page because the caller, * scan_movable_pages, scans through a given pfn-range which typically -- cgit v1.2.3-55-g7522