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From:   Cong Wang <xiyou.wangcong@gmail.com>
Date:   Tue, 18 Feb 2020 10:40:48 -0800
Message-ID: <CAM_iQpVegeSSWDWZTt4+ZT6qE3-AwsyHj7DAkFiFu8+8Hy-5jA@mail.gmail.com>
Subject: Re: [Patch v3] block: introduce block_rq_error tracepoint
To:     linux-block@vger.kernel.org
Cc:     LKML <linux-kernel@vger.kernel.org>, Jens Axboe <axboe@kernel.dk>,
        Steven Rostedt <rostedt@goodmis.org>
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Hi, Jens


On Sun, Feb 2, 2020 at 9:37 PM Cong Wang <xiyou.wangcong@gmail.com> wrote:
>
> Currently, rasdaemon uses the existing tracepoint block_rq_complete
> and filters out non-error cases in order to capture block disk errors.
>
> But there are a few problems with this approach:
>
> 1. Even kernel trace filter could do the filtering work, there is
>    still some overhead after we enable this tracepoint.
>
> 2. The filter is merely based on errno, which does not align with kernel
>    logic to check the errors for print_req_error().
>
> 3. block_rq_complete only provides dev major and minor to identify
>    the block device, it is not convenient to use in user-space.
>
> So introduce a new tracepoint block_rq_error just for the error case
> and provides the device name for convenience too. With this patch,
> rasdaemon could switch to block_rq_error.
>
> Cc: Jens Axboe <axboe@kernel.dk>
> Cc: Steven Rostedt <rostedt@goodmis.org>
> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>

Can you take this patch?

Thanks!