From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030261AbbCSRLp (ORCPT ); Thu, 19 Mar 2015 13:11:45 -0400 Received: from mga03.intel.com ([134.134.136.65]:27875 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756536AbbCSRLa (ORCPT ); Thu, 19 Mar 2015 13:11:30 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,430,1422950400"; d="scan'208";a="667640595" From: "Kirill A. Shutemov" To: Andrew Morton , Andrea Arcangeli , Hugh Dickins Cc: Dave Hansen , Mel Gorman , Rik van Riel , Vlastimil Babka , Christoph Lameter , Naoya Horiguchi , Steve Capper , "Aneesh Kumar K.V" , Johannes Weiner , Michal Hocko , Jerome Marchand , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCH 05/16] page-flags: define behavior of FS/IO-related flags on compound pages Date: Thu, 19 Mar 2015 19:08:11 +0200 Message-Id: <1426784902-125149-6-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1426784902-125149-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1426784902-125149-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org It seems we don't have compound page on FS/IO path currently. Use NO_COMPOUND to catch if we have. The odd expection is PG_dirty: sound uses compound pages and maps them with PTEs. NO_COMPOUND triggers VM_BUG_ON() in set_page_dirty() on handling shared fault. Let's use HEAD for PG_dirty. Signed-off-by: Kirill A. Shutemov --- include/linux/page-flags.h | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 10bdde20b14c..df2493860821 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -270,16 +270,16 @@ static inline struct page *compound_head_fast(struct page *page) } __PAGEFLAG(Locked, locked, NO_TAIL) -PAGEFLAG(Error, error, ANY) TESTCLEARFLAG(Error, error, ANY) +PAGEFLAG(Error, error, NO_COMPOUND) TESTCLEARFLAG(Error, error, NO_COMPOUND) PAGEFLAG(Referenced, referenced, ANY) TESTCLEARFLAG(Referenced, referenced, ANY) __SETPAGEFLAG(Referenced, referenced, ANY) -PAGEFLAG(Dirty, dirty, ANY) TESTSCFLAG(Dirty, dirty, ANY) - __CLEARPAGEFLAG(Dirty, dirty, ANY) +PAGEFLAG(Dirty, dirty, HEAD) TESTSCFLAG(Dirty, dirty, HEAD) + __CLEARPAGEFLAG(Dirty, dirty, HEAD) PAGEFLAG(LRU, lru, ANY) __CLEARPAGEFLAG(LRU, lru, ANY) PAGEFLAG(Active, active, ANY) __CLEARPAGEFLAG(Active, active, ANY) TESTCLEARFLAG(Active, active, ANY) __PAGEFLAG(Slab, slab, ANY) -PAGEFLAG(Checked, checked, ANY) /* Used by some filesystems */ +PAGEFLAG(Checked, checked, NO_COMPOUND) /* Used by some filesystems */ PAGEFLAG(Pinned, pinned, ANY) TESTSCFLAG(Pinned, pinned, ANY) /* Xen */ PAGEFLAG(SavePinned, savepinned, ANY); /* Xen */ PAGEFLAG(Foreign, foreign, ANY); /* Xen */ @@ -305,12 +305,15 @@ PAGEFLAG(OwnerPriv1, owner_priv_1, ANY) * Only test-and-set exist for PG_writeback. The unconditional operators are * risky: they bypass page accounting. */ -TESTPAGEFLAG(Writeback, writeback, ANY) TESTSCFLAG(Writeback, writeback, ANY) -PAGEFLAG(MappedToDisk, mappedtodisk, ANY) +TESTPAGEFLAG(Writeback, writeback, NO_COMPOUND) + TESTSCFLAG(Writeback, writeback, NO_COMPOUND) +PAGEFLAG(MappedToDisk, mappedtodisk, NO_COMPOUND) /* PG_readahead is only used for reads; PG_reclaim is only for writes */ -PAGEFLAG(Reclaim, reclaim, ANY) TESTCLEARFLAG(Reclaim, reclaim, ANY) -PAGEFLAG(Readahead, reclaim, ANY) TESTCLEARFLAG(Readahead, reclaim, ANY) +PAGEFLAG(Reclaim, reclaim, NO_COMPOUND) + TESTCLEARFLAG(Reclaim, reclaim, NO_COMPOUND) +PAGEFLAG(Readahead, reclaim, NO_COMPOUND) + TESTCLEARFLAG(Readahead, reclaim, NO_COMPOUND) #ifdef CONFIG_HIGHMEM /* @@ -419,7 +422,7 @@ static inline int PageUptodate(struct page *page) static inline void __SetPageUptodate(struct page *page) { smp_wmb(); - __set_bit(PG_uptodate, &(page)->flags); + __set_bit(PG_uptodate, &page->flags); } static inline void SetPageUptodate(struct page *page) @@ -430,7 +433,7 @@ static inline void SetPageUptodate(struct page *page) * uptodate are actually visible before PageUptodate becomes true. */ smp_wmb(); - set_bit(PG_uptodate, &(page)->flags); + set_bit(PG_uptodate, &page->flags); } CLEARPAGEFLAG(Uptodate, uptodate, ANY) -- 2.1.4