Hillf Danton wrote: > On Fri, Mar 15, 2013 at 9:50 PM, Kirill A. Shutemov > <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > > Hillf Danton wrote: > >> On Fri, Mar 15, 2013 at 9:23 PM, Kirill A. Shutemov > >> <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > >> > Hillf Danton wrote: > >> >> On Fri, Mar 15, 2013 at 1:50 AM, Kirill A. Shutemov > >> >> <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > >> >> > + page_cache_get(page); > >> >> > + spin_lock_irq(&mapping->tree_lock); > >> >> > + page->mapping = mapping; > >> >> > + page->index = offset; > >> >> > + error = radix_tree_insert(&mapping->page_tree, offset, page); > >> >> > + if (unlikely(error)) > >> >> > + goto err; > >> >> > + if (PageTransHuge(page)) { > >> >> > + int i; > >> >> > + for (i = 1; i < HPAGE_CACHE_NR; i++) { > >> >> struct page *tail = page + i; to easy reader > >> >> > >> >> > + page_cache_get(page + i); > >> >> s/page_cache_get/get_page_foll/ ? > >> > > >> > Why? > >> > > >> see follow_trans_huge_pmd() please. > > > > Sorry, I fail to see how follow_trans_huge_pmd() is relevant here. > > Could you elaborate? > > > Lets see the code > > page += (addr & ~HPAGE_PMD_MASK) >> PAGE_SHIFT; > //page is tail now > VM_BUG_ON(!PageCompound(page)); > if (flags & FOLL_GET) > get_page_foll(page); > //raise page count with the foll function > > thus I raised question. get_page_foll() is designed to be part of follow_page*() call chain. get_page() can handle compound pages properly. -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>