lkml.org 
[lkml]   [2019]   [Nov]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1 5/5] scsi: ufs: Complete pending requests in host reset and restore path
On 2019-11-13 10:24, Alim Akhtar wrote:
> Hi Can,
>
> On Fri, Nov 8, 2019 at 1:50 PM Can Guo <cang@codeaurora.org> wrote:
>>
>> In UFS host reset and restore path, before probe, we stop and start
>> the
>> host controller once. After host controller is stopped, the pending
>> requests, if any, are cleared from the doorbell, but no completion IRQ
>> would be raised due to the hba is stopped.
>> These pending requests shall be completed along with the first NOP_OUT
>> command(as it is the first command which can raise a transfer
>> completion
>> IRQ) sent during probe.
>> Since the OCSs of these pending requests are not SUCCESS(because they
>> are
>> not yet literally finished), their UPIUs shall be dumped. When there
>> are
>> multiple pending requests, the UPIU dump can be overwhelming and may
>> lead
>> to stability issues because it is in atomic context.
>> Therefore, before probe, complete these pending requests right after
>> host
>> controller is stopped.
>>
>> Signed-off-by: Can Guo <cang@codeaurora.org>
>> ---
> Looks good, I hope this is tested on your platform.
> Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
>

Hi Alim,

Thanks for the review. We've tested it out on our platforms.

Best regards,
Can Guo.

>> drivers/scsi/ufs/ufshcd.c | 20 +++++++-------------
>> 1 file changed, 7 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
>> index 5950a7c..4df4136 100644
>> --- a/drivers/scsi/ufs/ufshcd.c
>> +++ b/drivers/scsi/ufs/ufshcd.c
>> @@ -5404,8 +5404,8 @@ static void ufshcd_err_handler(struct
>> work_struct *work)
>>
>> /*
>> * if host reset is required then skip clearing the pending
>> - * transfers forcefully because they will automatically get
>> - * cleared after link startup.
>> + * transfers forcefully because they will get cleared during
>> + * host reset and restore
>> */
>> if (needs_reset)
>> goto skip_pending_xfer_clear;
>> @@ -6333,9 +6333,13 @@ static int ufshcd_host_reset_and_restore(struct
>> ufs_hba *hba)
>> int err;
>> unsigned long flags;
>>
>> - /* Reset the host controller */
>> + /*
>> + * Stop the host controller and complete the requests
>> + * cleared by h/w
>> + */
>> spin_lock_irqsave(hba->host->host_lock, flags);
>> ufshcd_hba_stop(hba, false);
>> + ufshcd_complete_requests(hba);
>> spin_unlock_irqrestore(hba->host->host_lock, flags);
>>
>> /* scale up clocks to max frequency before full
>> reinitialization */
>> @@ -6369,7 +6373,6 @@ static int ufshcd_host_reset_and_restore(struct
>> ufs_hba *hba)
>> static int ufshcd_reset_and_restore(struct ufs_hba *hba)
>> {
>> int err = 0;
>> - unsigned long flags;
>> int retries = MAX_HOST_RESET_RETRIES;
>>
>> do {
>> @@ -6379,15 +6382,6 @@ static int ufshcd_reset_and_restore(struct
>> ufs_hba *hba)
>> err = ufshcd_host_reset_and_restore(hba);
>> } while (err && --retries);
>>
>> - /*
>> - * After reset the door-bell might be cleared, complete
>> - * outstanding requests in s/w here.
>> - */
>> - spin_lock_irqsave(hba->host->host_lock, flags);
>> - ufshcd_transfer_req_compl(hba);
>> - ufshcd_tmc_handler(hba);
>> - spin_unlock_irqrestore(hba->host->host_lock, flags);
>> -
>> return err;
>> }
>>
>> --
>> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
>> Forum,
>> a Linux Foundation Collaborative Project
>>

\
 
 \ /
  Last update: 2019-11-13 04:03    [W:0.127 / U:0.312 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site