On Tue, 2024-06-25 at 09:13 -0700, Bart Van Assche wrote: > > External email : Please do not click links or open attachments until > you have verified the sender or the content. > On 6/24/24 8:38 PM, Peter Wang (王信友) wrote: > > But ufshcd_scsi_block_requests usage is correct in SDR mode. > > ufshcd_scsi_block_requests() uses scsi_block_requests(). It is almost > never correct to use scsi_block_requests() in a blk-mq driver because > scsi_block_requests() does not wait for ongoing request submission > calls to complete. scsi_block_requests() is a legacy from the time > when > all request dispatching and queueing was protected by the SCSI host > lock, a change that was made in 2010 or about 14 years ago. See also > https://lore.kernel.org/linux-scsi/20101105002409.GA21714@xxxxxxxxxxxxx/ > > > So, I think ufshcd_wait_for_doorbell_clr should be revise. > > Check tr_doorbell in SDR mode. (before 8d077ede48c1 do) > > Check each HWQ's are all empty in MCQ mode. (need think how to do) > > Make sure all requests is complete, and finish this function' job > > correctly. > > Or there still have a gap in ufshcd_wait_for_doorbell_clr. > > ufshcd_wait_for_doorbell_clr() should be removed and > ufshcd_clock_scaling_prepare() should use blk_mq_freeze_*(). > See also my patch "ufs: Simplify the clock scaling mechanism > implementation" from 5 years ago > ( > https://lore.kernel.org/linux-scsi/20191112173743.141503-5-bvanassche@xxxxxxx/ > ). > > Best regards, > > Bart. Hi Bart, Yes, remove ufshcd_wait_for_doorbell_clr() is more reasonable if this function cannot make sure all on-going request is done. Thanks. Peter
