On 05/11/2013 06:23 PM, Kirill A. Shutemov wrote: > From: "Kirill A. Shutemov" <[email protected]> > > replace_page_cache_page() is only used by FUSE. It's unlikely that we > will support THP in FUSE page cache any soon. > > Let's pospone implemetation of THP handling in replace_page_cache_page() > until any will use it. ... > diff --git a/mm/filemap.c b/mm/filemap.c > index 657ce82..3a03426 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -428,6 +428,8 @@ int replace_page_cache_page(struct page *old, struct page > *new, gfp_t gfp_mask) > { > int error; > > + VM_BUG_ON(PageTransHuge(old)); > + VM_BUG_ON(PageTransHuge(new)); > VM_BUG_ON(!PageLocked(old)); > VM_BUG_ON(!PageLocked(new)); > VM_BUG_ON(new->mapping);
The code calling replace_page_cache_page() has a bunch of fallback and error returning code. It seems a little bit silly to bring the whole machine down when you could just WARN_ONCE() and return an error code like fuse already does: > /* > * This is a new and locked page, it shouldn't be mapped or > * have any special flags on it > */ > if (WARN_ON(page_mapped(oldpage))) > goto out_fallback_unlock; > if (WARN_ON(page_has_private(oldpage))) > goto out_fallback_unlock; > if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage))) > goto out_fallback_unlock; > if (WARN_ON(PageMlocked(oldpage))) > goto out_fallback_unlock; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
