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Date:   Tue, 30 Jun 2020 20:49:58 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Martin Kepplinger <martin.kepplinger@puri.sm>, jejb@linux.ibm.com,
        Can Guo <cang@codeaurora.org>, martin.petersen@oracle.com,
        linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel@puri.sm
Subject: Re: [PATCH] scsi: sd: add runtime pm to open / release
Message-ID: <20200701004958.GA473187@rowland.harvard.edu>
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On Tue, Jun 30, 2020 at 04:31:58PM -0700, Bart Van Assche wrote:
> On 2020-06-30 12:38, Alan Stern wrote:
> > Assume that BLK_MQ_REQ_PREEMPT is set in flags.  Then where exactly 
> > does blk_queue_enter(q, flags) call blk_pm_request_resume(q)?
> 
> Please take a look at how the *current* implementation of runtime power
> management works. Your question is relevant for the old implementation
> of runtime power management but not for the current implementation.

What do you mean by "current"?  I have been looking at the implementation 
in 5.8-rc3 from Linus's tree.  Should I look somewhere else?

Alan Stern