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Subject: RE: Re: [PATCH] scsi: ufs: Refactor ufshcd_is_intr_aggr_allowed()
Reply-To: keosung.park@samsung.com
Sender: Keoseong Park <keosung.park@samsung.com>
From:   Keoseong Park <keosung.park@samsung.com>
To:     Adrian Hunter <adrian.hunter@intel.com>,
        Keoseong Park <keosung.park@samsung.com>,
        "joe@perches.com" <joe@perches.com>,
        ALIM AKHTAR <alim.akhtar@samsung.com>,
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        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>,
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        "beanhuo@micron.com" <beanhuo@micron.com>,
        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
        Kiwoong Kim <kwmad.kim@samsung.com>,
        "satyat@google.com" <satyat@google.com>,
        "bvanassche@acm.org" <bvanassche@acm.org>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Joao Pinto <jpinto@synopsys.com>,
        Pedro Sousa <sousa@synopsys.com>,
        Pedro Sousa <pedrom.sousa@synopsys.com>
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Date:   Thu, 24 Jun 2021 19:44:10 +0900
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>On 24/06/21 9:41 am, Keoseong Park wrote:
>>> On 21/06/21 11:51 am, Keoseong Park wrote:
>>>> Change conditional compilation to IS_ENABLED macro,
>>>> and simplify if else statement to return statement.
>>>> No functional change.
>>>>
>>>> Signed-off-by: Keoseong Park <keosung.park@samsung.com>
>>>> ---
>>>>  drivers/scsi/ufs/ufshcd.h | 17 ++++++++---------
>>>>  1 file changed, 8 insertions(+), 9 deletions(-)
>>>>
>>>> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
>>>> index c98d540ac044..6d239a855753 100644
>>>> --- a/drivers/scsi/ufs/ufshcd.h
>>>> +++ b/drivers/scsi/ufs/ufshcd.h
>>>> @@ -893,16 +893,15 @@ static inline bool ufshcd_is_rpm_autosuspend_allowed(struct ufs_hba *hba)
>>>>  
>>>>  static inline bool ufshcd_is_intr_aggr_allowed(struct ufs_hba *hba)
>>>>  {
>>>> -/* DWC UFS Core has the Interrupt aggregation feature but is not detectable*/
>>>> -#ifndef CONFIG_SCSI_UFS_DWC
>>>> -	if ((hba->caps & UFSHCD_CAP_INTR_AGGR) &&
>>>> -	    !(hba->quirks & UFSHCD_QUIRK_BROKEN_INTR_AGGR))
>>>> +	/*
>>>> +	 * DWC UFS Core has the Interrupt aggregation feature
>>>> +	 * but is not detectable.
>>>> +	 */
>>>> +	if (IS_ENABLED(CONFIG_SCSI_UFS_DWC))
>>>
>>> Why is this needed?  It seems like you could just set UFSHCD_CAP_INTR_AGGR
>>> and clear UFSHCD_QUIRK_BROKEN_INTR_AGGR instead?
>> 
>> Hello Adrian,
>> Sorry for late reply.
>> 
>> The code that returns true when CONFIG_SCSI_UFS_DWC is set in the original code 
>> is only changed using the IS_ENABLED macro.
>> (Linux kernel coding style, 21) Conditional Compilation)
>> 
>> When CONFIG_SCSI_UFS_DWC is not defined, the code for checking quirk 
>> and caps has been moved to the newly added return statement below.
>
>Looking closer I cannot find CONFIG_SCSI_UFS_DWC at all.  It seems like it
>never existed.
>
>Why should we not remove the code related to CONFIG_SCSI_UFS_DWC entirely?

You're right. What do you think of deleting the code related to CONFIG_SCSI_UFS_DWC 
and changing it to the patch below?

---
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index c98d540ac044..c9faca237290 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -893,16 +893,8 @@ static inline bool ufshcd_is_rpm_autosuspend_allowed(struct ufs_hba *hba)

 static inline bool ufshcd_is_intr_aggr_allowed(struct ufs_hba *hba)
 {
-/* DWC UFS Core has the Interrupt aggregation feature but is not detectable*/
-#ifndef CONFIG_SCSI_UFS_DWC
-       if ((hba->caps & UFSHCD_CAP_INTR_AGGR) &&
-           !(hba->quirks & UFSHCD_QUIRK_BROKEN_INTR_AGGR))
-               return true;
-       else
-               return false;
-#else
-return true;
-#endif
+       return (hba->caps & UFSHCD_CAP_INTR_AGGR) &&
+               !(hba->quirks & UFSHCD_QUIRK_BROKEN_INTR_AGGR);
 }

>
>
>> 
>> Thanks,
>> Keoseong
>> 
>>>
>>>>  		return true;
>>>> -	else
>>>> -		return false;
>>>> -#else
>>>> -return true;
>>>> -#endif
>>>> +
>>>> +	return (hba->caps & UFSHCD_CAP_INTR_AGGR) &&
>>>> +		!(hba->quirks & UFSHCD_QUIRK_BROKEN_INTR_AGGR);
>>>>  }
>>>>  
>>>>  static inline bool ufshcd_can_aggressive_pc(struct ufs_hba *hba)
>>>>
>>>
>