forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE

Browse source 
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 <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Sasha Levin 2014-01-23 15:52:54 -08:00 • committed by Linus Torvalds
parent e3bba3c3c9
commit 309381feae
30 changed files with 181 additions and 170 deletions
Download patch file Download diff file Expand all files Collapse all files

10
mm/rmap.c
View file

@ -894,9 +894,9 @@ void page_move_anon_rmap(struct page *page,
{
struct anon_vma *anon_vma = vma->anon_vma;
VM_BUG_ON(!PageLocked(page));
VM_BUG_ON_PAGE(!PageLocked(page), page);
VM_BUG_ON(!anon_vma);
VM_BUG_ON(page->index != linear_page_index(vma, address));
VM_BUG_ON_PAGE(page->index != linear_page_index(vma, address), page);
anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON;
page->mapping = (struct address_space *) anon_vma;
@ -995,7 +995,7 @@ void do_page_add_anon_rmap(struct page *page,
if (unlikely(PageKsm(page)))
return;
VM_BUG_ON(!PageLocked(page));
VM_BUG_ON_PAGE(!PageLocked(page), page);
/* address might be in next vma when migration races vma_adjust */
if (first)
__page_set_anon_rmap(page, vma, address, exclusive);
@ -1481,7 +1481,7 @@ int try_to_unmap(struct page *page, enum ttu_flags flags)
.anon_lock = page_lock_anon_vma_read,
};
VM_BUG_ON(!PageHuge(page) && PageTransHuge(page));
VM_BUG_ON_PAGE(!PageHuge(page) && PageTransHuge(page), page);
/*
* During exec, a temporary VMA is setup and later moved.
@ -1533,7 +1533,7 @@ int try_to_munlock(struct page *page)
};
VM_BUG_ON(!PageLocked(page) || PageLRU(page));
VM_BUG_ON_PAGE(!PageLocked(page) || PageLRU(page), page);
ret = rmap_walk(page, &rwc);
return ret;