Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <9fb79479-454d-d636-5554-5e080f05415e@quicinc.com>
Date:   Thu, 28 Jul 2022 13:00:30 -0700
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101
 Thunderbird/102.0.3
Subject: Re: [PATCH 1/2] scsi: ufs: Add Multi-Circular Queue support
To:     Bart Van Assche <bvanassche@acm.org>,
        Can Guo <quic_cang@quicinc.com>, <stanley.chu@mediatek.com>,
        <adrian.hunter@intel.com>, <alim.akhtar@samsung.com>,
        <avri.altman@wdc.com>, <beanhuo@micron.com>,
        <quic_nguyenb@quicinc.com>, <quic_ziqichen@quicinc.com>,
        <linux-scsi@vger.kernel.org>, <kernel-team@android.com>
CC:     "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Daejun Park <daejun7.park@samsung.com>,
        Jinyoung Choi <j-young.choi@samsung.com>,
        Kiwoong Kim <kwmad.kim@samsung.com>,
        open list <linux-kernel@vger.kernel.org>
References: <1658214120-22772-1-git-send-email-quic_cang@quicinc.com>
 <1658214120-22772-2-git-send-email-quic_cang@quicinc.com>
 <f803e7fb-9dde-e4d4-a55c-6427516dfdbb@acm.org>
From:   "Asutosh Das (asd)" <quic_asutoshd@quicinc.com>
In-Reply-To: <f803e7fb-9dde-e4d4-a55c-6427516dfdbb@acm.org>
Content-Type: text/plain; charset="UTF-8"; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk

On 7/28/2022 12:38 PM, Bart Van Assche wrote:
> On 7/19/22 00:01, Can Guo wrote:
>>   static int ufshcd_map_queues(struct Scsi_Host *shost)
>>   {
>> -    int i, ret;
>> +    int i, queue_offset = 0, ret;
>> +    struct ufs_hba *hba = shost_priv(shost);
>>       for (i = 0; i < shost->nr_maps; i++) {
>>           struct blk_mq_queue_map *map = &shost->tag_set.map[i];
>> -        switch (i) {
>> -        case HCTX_TYPE_DEFAULT:
>> -        case HCTX_TYPE_POLL:
>> -            map->nr_queues = 1;
>> -            break;
>> -        case HCTX_TYPE_READ:
>> -            map->nr_queues = 0;
>> +        map->nr_queues = hba->nr_queues[i];
>> +        if (!map->nr_queues)
>>               continue;
>> -        default:
>> -            WARN_ON_ONCE(true);
>> -        }
>> -        map->queue_offset = 0;
>> +
>> +        map->queue_offset = queue_offset;
>> +        if (i == HCTX_TYPE_POLL && !is_mcq_enabled(hba))
>> +            map->queue_offset = 0;
>> +
>>           ret = blk_mq_map_queues(map);
>> -        WARN_ON_ONCE(ret);
>> +
>> +        if (ret)
>> +            return ret;
>> +
>> +        queue_offset += map->nr_queues;
>>       }
> 
> It is not clear to me why the WARN_ON_ONCE(ret) statement has been 
> changed into "if (ret) return ret;"?
> 
Looks like blk_mq_map_queues() only returns 0.
Will remove the if (ret) return ret statement in the next version.

> Thanks,
> 
> Bart.