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Subject: RE: [PATCH v4 3/9] scsi: ufshpb: Add region's reads counter
Reply-To: daejun7.park@samsung.com
Sender: Daejun Park <daejun7.park@samsung.com>
From:   Daejun Park <daejun7.park@samsung.com>
To:     "James E . J . Bottomley" <jejb@linux.vnet.ibm.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC:     "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
        Bart Van Assche <bvanassche@acm.org>,
        yongmyung lee <ymhungry.lee@samsung.com>,
        Daejun Park <daejun7.park@samsung.com>,
        ALIM AKHTAR <alim.akhtar@samsung.com>,
        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
        Zang Leigang <zangleigang@hisilicon.com>,
        Avi Shchislowski <avi.shchislowski@wdc.com>,
        Bean Huo <beanhuo@micron.com>,
        "cang@codeaurora.org" <cang@codeaurora.org>,
        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>,
        Avri Altman <avri.altman@wdc.com>
In-Reply-To: <20210226083300.30934-4-avri.altman@wdc.com>
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Date:   Tue, 02 Mar 2021 17:31:10 +0900
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References: <20210226083300.30934-4-avri.altman@wdc.com>
        <20210226083300.30934-1-avri.altman@wdc.com>
        <CGME20210226083422epcas2p2d39acff666e2cb9ed97bc2d5c7a8df6f@epcms2p5>
Precedence: bulk

Hi Avri,

> +static void ufshpb_normalization_work_handler(struct work_struct *work)
> +{
> +        struct ufshpb_lu *hpb;
> +        int rgn_idx;
> +
> +        hpb = container_of(work, struct ufshpb_lu, ufshpb_normalization_work);
> +
> +        for (rgn_idx = 0; rgn_idx < hpb->rgns_per_lu; rgn_idx++) {
> +                struct ufshpb_region *rgn = hpb->rgn_tbl + rgn_idx;

*HERE*
> +                if (rgn->reads) {
> +                        unsigned long flags;
> +
> +                        spin_lock_irqsave(&rgn->rgn_lock, flags);

I thinks this lock should protect rgn->reads when it is accessed.

> +                        rgn->reads = (rgn->reads >> 1);
> +                        spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> +                }
*HERE*

> +
> +                if (rgn->rgn_state != HPB_RGN_ACTIVE || rgn->reads)
> +                        continue;
> +
> +                /* if region is active but has no reads - inactivate it */
> +                spin_lock(&hpb->rsp_list_lock);
> +                ufshpb_update_inactive_info(hpb, rgn->rgn_idx);
> +                spin_unlock(&hpb->rsp_list_lock);
> +        }
> +
> +        clear_bit(WORK_PENDING, &hpb->work_data_bits);

Why we use work_data_bits? It may be checked by worker API.

Thanks,
Daejun