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To:     Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        <wen.yang99@zte.com.cn>
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From:   Jason Yan <yanaijie@huawei.com>
Message-ID: <5AC1C8BF.1030503@huawei.com>
Date:   Mon, 2 Apr 2018 14:07:59 +0800
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On 2018/4/2 13:29, Sergey Senozhatsky wrote:
> On (04/02/18 13:14), wen.yang99@zte.com.cn wrote:
>>
>>     > It's true that this print for the same device is useless. But it's
>>     > useful for different devices. Is it possible to limit the print only
>>     > for the same device?
>>
>>     In our scene, it's  just for the same device (q->queuedata), Thanks.
>
> Yes, what Jason meant was that rate limit struct is shared by different call
> sites - including scsi_request_fn() from different devices.
>
> If device1->scsi_request_fn()->sdev_printk_ratelimited() causes printk rate
> limit, then messages from device2->scsi_request_fn()->sdev_printk_ratelimited()
> may be lost entirely, unless you have enough of them.
>
> 	-ss
>

Yes, that's exactly what I mean.

Thanks,

Jason

> .
>