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Date:   Sat, 19 Dec 2020 13:55:20 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Avri Altman <Avri.Altman@wdc.com>
Cc:     Daejun Park <daejun7.park@samsung.com>,
        "jejb@linux.ibm.com" <jejb@linux.ibm.com>,
        "martin.petersen@oracle.com" <martin.petersen@oracle.com>,
        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>,
        "cang@codeaurora.org" <cang@codeaurora.org>,
        "huobean@gmail.com" <huobean@gmail.com>,
        "bvanassche@acm.org" <bvanassche@acm.org>,
        ALIM AKHTAR <alim.akhtar@samsung.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Sung-Jun Park <sungjun07.park@samsung.com>,
        yongmyung lee <ymhungry.lee@samsung.com>,
        Jinyoung CHOI <j-young.choi@samsung.com>,
        Adel Choi <adel.choi@samsung.com>,
        BoRam Shin <boram.shin@samsung.com>,
        SEUNGUK SHIN <seunguk.shin@samsung.com>
Subject: Re: [PATCH v16 1/3] scsi: ufs: Introduce HPB feature
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On Sat, Dec 19, 2020 at 12:48:31PM +0000, Avri Altman wrote:
> > 
> > 
> > On Sat, Dec 19, 2020 at 06:18:47PM +0900, Daejun Park wrote:
> > > +static int ufshpb_get_state(struct ufshpb_lu *hpb)
> > > +{
> > > +     return atomic_read(&hpb->hpb_state);
> > > +}
> > > +
> > > +static void ufshpb_set_state(struct ufshpb_lu *hpb, int state)
> > > +{
> > > +     atomic_set(&hpb->hpb_state, state);
> > > +}
> > 
> > You have a lock for the state, and yet the state is an atomic variable
> > and you do not use the lock here at all.  You don't use the lock at all
> > infact...
> > 
> > So either the lock needs to be dropped, or you need to use the lock and
> > make the state a normal variable please.
> hpb_state_lock is mainly protecting the list of active regions.
> Just grep  lh_lru_rgn in patch 2/3.

Then why is the lock added in this patch if it is not used here?

thanks,

greg k-h