From: Christoph Hellwig <hch@infradead.org>
To: Nick Piggin <npiggin@kernel.dk>
Cc: Dave Chinner <david@fromorbit.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 04/21] fs: Implement lazy LRU updates for inodes
Date: Thu, 21 Oct 2010 08:22:22 -0400 [thread overview]
Message-ID: <20101021122221.GA3236@infradead.org> (raw)
In-Reply-To: <20101021100706.GA9797@amd>
On Thu, Oct 21, 2010 at 09:07:06PM +1100, Nick Piggin wrote:
> On Thu, Oct 21, 2010 at 11:49:29AM +1100, Dave Chinner wrote:
> > } else {
> > /*
> > - * The inode is clean, unused
> > + * The inode is clean. If it is unused, then make sure
> > + * that it is put on the LRU correctly as iput_final()
> > + * does not move dirty inodes to the LRU and dirty
> > + * inodes are removed from the LRU during scanning.
> > */
> > - list_move(&inode->i_list, &inode_unused);
> > + list_del_init(&inode->i_list);
> > + if (!atomic_read(&inode->i_count))
> > + inode_lru_list_add(inode);
>
> This "optimisation" is surely wrong. How could we have no reference
> on the inode at this point?
Good question. iput_final does so for unlinked inodes or umount,
and that should be about it as it's the only place setting I_WILL_FREE
and we require that for a 0 refcount at the beginning of
writeback_single_inode. But adding it to the LRU case for that
is rather pointless as we will remove it a little bit later.
So I think the assignment can be safely removed, but I'd rather do in
a separate, properly documented patch rather than hiding it somewhere
unrelated. That patch could however go towards the beggining of the
series to make things easier.
next prev parent reply other threads:[~2010-10-21 12:22 UTC|newest]
Thread overview: 58+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-21 0:49 Inode Lock Scalability V6 Dave Chinner
2010-10-21 0:49 ` [PATCH 01/21] fs: switch bdev inode bdi's correctly Dave Chinner
2010-10-21 0:49 ` [PATCH 02/21] kernel: add bl_list Dave Chinner
2010-10-21 0:49 ` [PATCH 03/21] fs: Convert nr_inodes and nr_unused to per-cpu counters Dave Chinner
2010-10-21 0:49 ` [PATCH 04/21] fs: Implement lazy LRU updates for inodes Dave Chinner
2010-10-21 2:14 ` Christian Stroetmann
2010-10-21 10:07 ` Nick Piggin
2010-10-21 12:22 ` Christoph Hellwig [this message]
2010-10-23 9:32 ` Al Viro
2010-10-21 0:49 ` [PATCH 05/21] fs: inode split IO and LRU lists Dave Chinner
2010-10-21 0:49 ` [PATCH 06/21] fs: Clean up inode reference counting Dave Chinner
2010-10-21 1:41 ` Christoph Hellwig
2010-10-21 0:49 ` [PATCH 07/21] exofs: use iput() for inode reference count decrements Dave Chinner
2010-10-21 0:49 ` [PATCH 08/21] fs: rework icount to be a locked variable Dave Chinner
2010-10-21 19:40 ` Al Viro
2010-10-21 22:32 ` Dave Chinner
2010-10-21 0:49 ` [PATCH 09/21] fs: Factor inode hash operations into functions Dave Chinner
2010-10-21 0:49 ` [PATCH 10/21] fs: Stop abusing find_inode_fast in iunique Dave Chinner
2010-10-21 0:49 ` [PATCH 11/21] fs: move i_ref increments into find_inode/find_inode_fast Dave Chinner
2010-10-21 0:49 ` [PATCH 12/21] fs: remove inode_add_to_list/__inode_add_to_list Dave Chinner
2010-10-21 0:49 ` [PATCH 13/21] fs: Introduce per-bucket inode hash locks Dave Chinner
2010-10-21 0:49 ` [PATCH 14/21] fs: add a per-superblock lock for the inode list Dave Chinner
2010-10-21 0:49 ` [PATCH 15/21] fs: split locking of inode writeback and LRU lists Dave Chinner
2010-10-21 0:49 ` [PATCH 16/21] fs: Protect inode->i_state with the inode->i_lock Dave Chinner
2010-10-22 1:56 ` Al Viro
2010-10-22 2:26 ` Nick Piggin
2010-10-22 3:14 ` Dave Chinner
2010-10-22 10:37 ` Al Viro
2010-10-22 11:40 ` Christoph Hellwig
2010-10-23 21:40 ` Al Viro
2010-10-23 21:37 ` Al Viro
2010-10-24 14:13 ` Christoph Hellwig
2010-10-24 16:21 ` Christoph Hellwig
2010-10-24 19:17 ` Al Viro
2010-10-24 20:04 ` Christoph Hellwig
2010-10-24 20:36 ` Al Viro
2010-10-24 2:18 ` Nick Piggin
2010-10-21 0:49 ` [PATCH 17/21] fs: protect wake_up_inode with inode->i_lock Dave Chinner
2010-10-21 2:17 ` Christoph Hellwig
2010-10-21 13:16 ` Nick Piggin
2010-10-21 0:49 ` [PATCH 18/21] fs: introduce a per-cpu last_ino allocator Dave Chinner
2010-10-21 0:49 ` [PATCH 19/21] fs: icache remove inode_lock Dave Chinner
2010-10-21 2:14 ` Christian Stroetmann
2010-10-21 0:49 ` [PATCH 20/21] fs: Reduce inode I_FREEING and factor inode disposal Dave Chinner
2010-10-21 0:49 ` [PATCH 21/21] fs: do not assign default i_ino in new_inode Dave Chinner
2010-10-21 5:04 ` Inode Lock Scalability V7 (was V6) Dave Chinner
2010-10-21 13:20 ` Nick Piggin
2010-10-21 23:52 ` Dave Chinner
2010-10-22 0:45 ` Nick Piggin
2010-10-22 2:20 ` Al Viro
2010-10-22 2:34 ` Nick Piggin
2010-10-22 2:41 ` Nick Piggin
2010-10-22 2:48 ` Nick Piggin
2010-10-22 3:12 ` Al Viro
2010-10-22 4:48 ` Nick Piggin
2010-10-22 3:07 ` Al Viro
2010-10-22 4:46 ` Nick Piggin
2010-10-22 5:01 ` Nick Piggin
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