From: Jens Axboe <axboe@kernel.dk>
To: Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>, Jan Kara <jack@suse.cz>
Cc: "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
"tristmd@gmail.com" <tristmd@gmail.com>,
"stable@vger.kernel.org" <stable@vger.kernel.org>,
Damien Le Moal <Damien.LeMoal@wdc.com>
Subject: Re: [PATCH] blktrace: Protect q->blk_trace with RCU
Date: Thu, 6 Feb 2020 11:49:40 -0700 [thread overview]
Message-ID: <ddc358fb-8189-fbe9-619d-e3c943a05053@kernel.dk> (raw)
In-Reply-To: <BYAPR04MB5749BAE3D6813845E16D92E2861D0@BYAPR04MB5749.namprd04.prod.outlook.com>
On 2/6/20 11:46 AM, Chaitanya Kulkarni wrote:
> Hi Jan,
>
> What do you think about following patch on the top of yours ?
>
> The new helper that I've added on the top of your patch will also
> future uses of the rcu_dereference_protected(). e.g. blktrace
> extension [1] support that I'm working on.
>
> P.S. it is compile only if your okay I'll send a separate patch.
>
> +
> +/* Dereference q->blk_trace with q->blk_trace_mutex check only. */
> +static inline struct blk_trace *blk_trace_rcu_deref(struct
> request_queue *q)
> +{
> + return rcu_dereference_protected(q->blk_trace,
> +
> lockdep_is_held(&q->blk_trace_mutex));
> +}
Let's please not do that, it serves no real purpose and it just
obfuscates what's really going on.
--
Jens Axboe
next prev parent reply other threads:[~2020-02-06 18:49 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-06 14:28 [PATCH] blktrace: Protect q->blk_trace with RCU Jan Kara
2020-02-06 18:46 ` Chaitanya Kulkarni
2020-02-06 18:49 ` Jens Axboe [this message]
2020-02-06 19:37 ` Chaitanya Kulkarni
2020-02-10 0:38 ` Chaitanya Kulkarni
2020-02-10 2:19 ` Ming Lei
2020-02-10 3:54 ` Bart Van Assche
2020-02-19 12:59 ` Jan Kara
2020-02-25 10:20 ` Ming Lei
2020-02-25 15:40 ` Jens Axboe
2020-03-02 20:40 ` Bjorn Helgaas
2020-03-02 21:19 ` Chaitanya Kulkarni
2020-03-02 21:59 ` Bjorn Helgaas
2020-03-02 22:06 ` Keith Busch
2020-03-03 11:07 ` Cengiz Can
2020-03-03 12:17 ` Greg KH
2020-03-05 1:51 ` Ming Lei
2020-03-05 4:27 ` Cengiz Can
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