On 6/12/21 12:38 AM, Can Guo wrote:
> On 2021-06-12 04:52, Bart Van Assche wrote:
>> On 6/9/21 9:43 PM, Can Guo wrote:
>>> @@ -2768,15 +2778,6 @@ static int ufshcd_queuecommand(struct
>>> Scsi_Host *host, struct scsi_cmnd *cmd)
>>> WARN_ON(ufshcd_is_clkgating_allowed(hba) &&
>>> (hba->clk_gating.state != CLKS_ON));
>>>
>>> - if (unlikely(test_bit(tag, &hba->outstanding_reqs))) {
>>> - if (hba->wl_pm_op_in_progress)
>>> - set_host_byte(cmd, DID_BAD_TARGET);
>>> - else
>>> - err = SCSI_MLQUEUE_HOST_BUSY;
>>> - ufshcd_release(hba);
>>> - goto out;
>>> - }
>>> -
>>> lrbp = &hba->lrb[tag];
>>> WARN_ON(lrbp->cmd);
>>> lrbp->cmd = cmd;
>>
>> Can the code under "if (unlikely(test_bit(tag,
>> &hba->outstanding_reqs)))" be deleted instead of moving it? I don't
>> think that it is useful to verify whether the block layer tag allocator
>> works correctly. Additionally, I'm not aware of any similar code in any
>> other SCSI LLD.
>
> ufshcd_abort() aborts PM requests differently from other requests -
> it simply evicts the cmd from lrbp [1], schedules error handler and
> returns SUCCESS (the reason why I am doing it this way is in patch #8).
>
> After ufshcd_abort() returns, the tag shall be released, the logic
> here is to prevent subsequent cmds re-use the lrbp [1] before error
> handler recovers the device and host.
Thanks for the background information. However, this approach sounds
cumbersome to me. For PM requests, please change the UFS driver such
that calling scsi_done() for aborted requests is postponed until error
handling has finished and delete the code shown above from
ufshcd_queuecommand().
Thanks,
Bart.
