Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1756195Ab3IISy1 (ORCPT <rfc822;w@1wt.eu>);
	Mon, 9 Sep 2013 14:54:27 -0400
Received: from mail-we0-f178.google.com ([74.125.82.178]:50583 "EHLO
	mail-we0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1754172Ab3IISyY (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Mon, 9 Sep 2013 14:54:24 -0400
MIME-Version: 1.0
In-Reply-To: <fd69f2052bc16d5a5de0104ca00ccc59478e3569.1378750714.git.milosz@adfin.com>
References: <alpine.DEB.2.00.1309091042520.18214@cobra.newdream.net>
	<fd69f2052bc16d5a5de0104ca00ccc59478e3569.1378750714.git.milosz@adfin.com>
Date: Mon, 9 Sep 2013 14:54:23 -0400
Message-ID: <CANP1eJHQhmYZomguVobCkkuvBK=JG8wzbJxMmgipSvJHF8vaQg@mail.gmail.com>
Subject: Re: [PATCH] fscache: check consistency does not decrement refcount
From: Milosz Tanski <milosz@adfin.com>
To: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@inktank.com>, "Yan, Zheng" <zheng.z.yan@intel.com>,
        "linux-cachefs@redhat.com" <linux-cachefs@redhat.com>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
        linux-kernel@vger.kernel.org, ceph-devel <ceph-devel@vger.kernel.org>
Content-Type: text/plain; charset=ISO-8859-1
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 2183
Lines: 57

David,

Can I get a sign off on this?

Thanks,
- Milosz

On Mon, Sep 9, 2013 at 2:28 PM, Milosz Tanski <milosz@adfin.com> wrote:
> __fscache_check_consistency() does not decrement the count of operations
> active after it finishes in the success case. This leads to a hung tasks on
> cookie de-registration (commonly in inode eviction).
>
> INFO: task kworker/1:2:4214 blocked for more than 120 seconds.
> kworker/1:2     D ffff880443513fc0     0  4214      2 0x00000000
> Workqueue: ceph-msgr con_work [libceph]
>   ...
> Call Trace:
>  [<ffffffff81569fc6>] ? _raw_spin_unlock_irqrestore+0x16/0x20
>  [<ffffffffa0016570>] ? fscache_wait_bit_interruptible+0x30/0x30 [fscache]
>  [<ffffffff81568d09>] schedule+0x29/0x70
>  [<ffffffffa001657e>] fscache_wait_atomic_t+0xe/0x20 [fscache]
>  [<ffffffff815665cf>] out_of_line_wait_on_atomic_t+0x9f/0xe0
>  [<ffffffff81083560>] ? autoremove_wake_function+0x40/0x40
>  [<ffffffffa0015a9c>] __fscache_relinquish_cookie+0x15c/0x310 [fscache]
>  [<ffffffffa00a4fae>] ceph_fscache_unregister_inode_cookie+0x3e/0x50 [ceph]
>  [<ffffffffa007e373>] ceph_destroy_inode+0x33/0x200 [ceph]
>  [<ffffffff811c13ae>] ? __fsnotify_inode_delete+0xe/0x10
>  [<ffffffff8119ba1c>] destroy_inode+0x3c/0x70
>  [<ffffffff8119bb69>] evict+0x119/0x1b0
>
> Signed-off-by: Milosz Tanski <milosz@adfin.com>
> ---
>  fs/fscache/cookie.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/fscache/cookie.c b/fs/fscache/cookie.c
> index 318e843..b2a86e3 100644
> --- a/fs/fscache/cookie.c
> +++ b/fs/fscache/cookie.c
> @@ -586,7 +586,8 @@ int __fscache_check_consistency(struct fscache_cookie *cookie)
>
>         fscache_operation_init(op, NULL, NULL);
>         op->flags = FSCACHE_OP_MYTHREAD |
> -               (1 << FSCACHE_OP_WAITING);
> +               (1 << FSCACHE_OP_WAITING) |
> +               (1 << FSCACHE_OP_UNUSE_COOKIE);
>
>         spin_lock(&cookie->lock);
>
> --
> 1.7.9.5
>
--
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/