Re: [PATCH v1] scsi: ufs: core: print trs for pending requests in MCQ mode

[Ziqi Chen <quic_ziqichen@xxxxxxxxxxx>]

Hi Bart,

Good idea, let met re-design it.

Thanks,
Ziqi

On 3/10/2023 1:28 AM, Bart Van Assche wrote:
> On 3/8/23 21:01, Ziqi Chen wrote:
> > +static void ufshcd_print_trs_all(struct ufs_hba *hba, bool pr_prdt)
> > +{
> > +    const struct ufshcd_lrb *lrbp;
> > +    int tag;
> > +
> > +    for (tag = 0; tag < hba->nutrs; tag++) {
> > +        lrbp = &hba->lrb[tag];
> > +
> > +        if (lrbp->cmd)
> > +            ufshcd_print_tr(hba, tag, pr_prdt);
> >       }
> >   }
>
> There is a race in this code: lrbp->cmd may be cleared after it has been 
> read and before or while ufshcd_print_tr() is in progress. How about 
> preventing that race by blk_mq_tagset_busy_iter() to iterate over 
> pending SCSI commands?
>
> Thanks,
>
> Bart.