Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754705Ab1DNXhx (ORCPT ); Thu, 14 Apr 2011 19:37:53 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:40313 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751368Ab1DNXhv convert rfc822-to-8bit (ORCPT ); Thu, 14 Apr 2011 19:37:51 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=jRBawvSdjLdI6r6p7c+g8PAJ/4iFkBJBMekMdJmptnkp/XzfcDAzVUxXJyv58zkqBW HWTnpI8RVnrgD95loxj9hFi5mj6yXmN30eBkpF1lJWM8b9KtDgEGmL9Z8cFiITNpN09s AHNBm/osHHGWJg3W39ngAxgrH7IzPjJf38/vc= MIME-Version: 1.0 In-Reply-To: <20110414211732.GA27761@ca-server1.us.oracle.com> References: <20110414211732.GA27761@ca-server1.us.oracle.com> Date: Fri, 15 Apr 2011 08:37:49 +0900 Message-ID: Subject: Re: [PATCH V8 4/8] mm/fs: add hooks to support cleancache From: Minchan Kim To: Dan Magenheimer Cc: chris.mason@oracle.com, viro@zeniv.linux.org.uk, akpm@linux-foundation.org, adilger.kernel@dilger.ca, tytso@mit.edu, mfasheh@suse.com, jlbec@evilplan.org, matthew@wil.cx, linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, ocfs2-devel@oss.oracle.com, linux-mm@kvack.org, hch@infradead.org, ngupta@vflare.org, jeremy@goop.org, JBeulich@novell.com, kurt.hackel@oracle.com, npiggin@kernel.dk, dave.mccracken@oracle.com, riel@redhat.com, avi@redhat.com, konrad.wilk@oracle.com, mel@csn.ul.ie, yinghan@google.com, gthelen@google.com, torvalds@linux-foundation.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6425 Lines: 160 Hi Dan, On Fri, Apr 15, 2011 at 6:17 AM, Dan Magenheimer wrote: > [PATCH V8 4/8] mm/fs: add hooks to support cleancache > > This fourth patch of eight in this cleancache series provides the > core hooks in VFS for: initializing cleancache per filesystem; > capturing clean pages reclaimed by page cache; attempting to get > pages from cleancache before filesystem read; and ensuring coherency > between pagecache, disk, and cleancache.  Note that the placement > of these hooks was stable from 2.6.18 to 2.6.38; a minor semantic > change was required due to a patchset in 2.6.39. > > All hooks become no-ops if CONFIG_CLEANCACHE is unset, or become > a check of a boolean global if CONFIG_CLEANCACHE is set but no > cleancache "backend" has claimed cleancache_ops. > > Details and a FAQ can be found in Documentation/vm/cleancache.txt > > [v8: minchan.kim@gmail.com: adapt to new remove_from_page_cache function] > Signed-off-by: Chris Mason > Signed-off-by: Dan Magenheimer > Reviewed-by: Jeremy Fitzhardinge > Reviewed-by: Konrad Rzeszutek Wilk > Cc: Andrew Morton > Cc: Al Viro > Cc: Matthew Wilcox > Cc: Nick Piggin > Cc: Mel Gorman > Cc: Rik Van Riel > Cc: Jan Beulich > Cc: Andreas Dilger > Cc: Ted Ts'o > Cc: Mark Fasheh > Cc: Joel Becker > Cc: Nitin Gupta > > --- > > Diffstat: >  fs/buffer.c                              |    5 +++++ >  fs/mpage.c                               |    7 +++++++ >  fs/super.c                               |    3 +++ >  mm/filemap.c                             |   11 +++++++++++ >  mm/truncate.c                            |    6 ++++++ >  5 files changed, 32 insertions(+) > > --- linux-2.6.39-rc3/fs/super.c 2011-04-11 18:21:51.000000000 -0600 > +++ linux-2.6.39-rc3-cleancache/fs/super.c      2011-04-13 17:08:09.175853426 -0600 > @@ -31,6 +31,7 @@ >  #include >  #include >  #include > +#include >  #include "internal.h" > > > @@ -112,6 +113,7 @@ static struct super_block *alloc_super(s >                s->s_maxbytes = MAX_NON_LFS; >                s->s_op = &default_op; >                s->s_time_gran = 1000000000; > +               s->cleancache_poolid = -1; >        } >  out: >        return s; > @@ -177,6 +179,7 @@ void deactivate_locked_super(struct supe >  { >        struct file_system_type *fs = s->s_type; >        if (atomic_dec_and_test(&s->s_active)) { > +               cleancache_flush_fs(s); >                fs->kill_sb(s); >                /* >                 * We need to call rcu_barrier so all the delayed rcu free > --- linux-2.6.39-rc3/fs/buffer.c        2011-04-11 18:21:51.000000000 -0600 > +++ linux-2.6.39-rc3-cleancache/fs/buffer.c     2011-04-13 17:07:24.700917174 -0600 > @@ -41,6 +41,7 @@ >  #include >  #include >  #include > +#include > >  static int fsync_buffers_list(spinlock_t *lock, struct list_head *list); > > @@ -269,6 +270,10 @@ void invalidate_bdev(struct block_device >        invalidate_bh_lrus(); >        lru_add_drain_all();    /* make sure all lru add caches are flushed */ >        invalidate_mapping_pages(mapping, 0, -1); > +       /* 99% of the time, we don't need to flush the cleancache on the bdev. > +        * But, for the strange corners, lets be cautious > +        */ > +       cleancache_flush_inode(mapping); >  } >  EXPORT_SYMBOL(invalidate_bdev); > > --- linux-2.6.39-rc3/fs/mpage.c 2011-04-11 18:21:51.000000000 -0600 > +++ linux-2.6.39-rc3-cleancache/fs/mpage.c      2011-04-13 17:07:24.706913410 -0600 > @@ -27,6 +27,7 @@ >  #include >  #include >  #include > +#include > >  /* >  * I/O completion handler for multipage BIOs. > @@ -271,6 +272,12 @@ do_mpage_readpage(struct bio *bio, struc >                SetPageMappedToDisk(page); >        } > > +       if (fully_mapped && blocks_per_page == 1 && !PageUptodate(page) && > +           cleancache_get_page(page) == 0) { > +               SetPageUptodate(page); > +               goto confused; > +       } > + >        /* >         * This page will go to BIO.  Do we need to send this BIO off first? >         */ > --- linux-2.6.39-rc3/mm/filemap.c       2011-04-11 18:21:51.000000000 -0600 > +++ linux-2.6.39-rc3-cleancache/mm/filemap.c    2011-04-13 17:09:46.367852002 -0600 > @@ -34,6 +34,7 @@ >  #include /* for BUG_ON(!in_atomic()) only */ >  #include >  #include /* for page_is_file_cache() */ > +#include >  #include "internal.h" > >  /* > @@ -118,6 +119,16 @@ void __delete_from_page_cache(struct pag >  { >        struct address_space *mapping = page->mapping; > > +       /* > +        * if we're uptodate, flush out into the cleancache, otherwise > +        * invalidate any existing cleancache entries.  We can't leave > +        * stale data around in the cleancache once our page is gone > +        */ > +       if (PageUptodate(page) && PageMappedToDisk(page)) > +               cleancache_put_page(page); > +       else > +               cleancache_flush_page(mapping, page); > + First of all, thanks for resolving conflict with my patch. Before I suggested a thing about cleancache_flush_page, cleancache_flush_inode. what's the meaning of flush's semantic? I thought it means invalidation. AFAIC, how about change flush with invalidate? -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/