Messages in this thread | | | Date | Mon, 08 Feb 2021 17:58:47 +0800 | From | Can Guo <> | Subject | Re: [PATCH v19 3/3] scsi: ufs: Prepare HPB read for cached sub-region |
| |
On 2021-02-08 16:16, Bean Huo wrote: > On Fri, 2021-02-05 at 11:29 +0800, Can Guo wrote: >> > + return ppn_table[offset]; >> > +} >> > + >> > +static void >> > +ufshpb_get_pos_from_lpn(struct ufshpb_lu *hpb, unsigned long lpn, >> > int >> > *rgn_idx, >> > + int *srgn_idx, int *offset) >> > +{ >> > + int rgn_offset; >> > + >> > + *rgn_idx = lpn >> hpb->entries_per_rgn_shift; >> > + rgn_offset = lpn & hpb->entries_per_rgn_mask; >> > + *srgn_idx = rgn_offset >> hpb->entries_per_srgn_shift; >> > + *offset = rgn_offset & hpb->entries_per_srgn_mask; >> > +} >> > + >> > +static void >> > +ufshpb_set_hpb_read_to_upiu(struct ufshpb_lu *hpb, struct >> > ufshcd_lrb >> > *lrbp, >> > + u32 lpn, u64 ppn, unsigned int >> > transfer_len) >> > +{ >> > + unsigned char *cdb = lrbp->cmd->cmnd; >> > + >> > + cdb[0] = UFSHPB_READ; >> > + >> > + put_unaligned_be64(ppn, &cdb[6]); >> >> You are assuming the HPB entries read out by "HPB Read Buffer" cmd >> are >> in Little >> Endian, which is why you are using put_unaligned_be64 here. >> > > > Actaully, here uses put_unaligned_be64 is no problem. SCSI command > should be big-endian filled. I Think the problem is that geting ppn > from HPB cache in ufshpb_get_ppn(). >
whatever...
> ... > e0000001f: 12 34 56 78 90 fa de ef > ... > > + > +static u64 ufshpb_get_ppn(struct ufshpb_lu *hpb, > + struct ufshpb_map_ctx *mctx, int pos, int > *error) > +{ > + u64 *ppn_table; // It s a 64 bits pointer > + struct page *page; > + int index, offset; > + > + index = pos / (PAGE_SIZE / HPB_ENTRY_SIZE); > + offset = pos % (PAGE_SIZE / HPB_ENTRY_SIZE); > + > + page = mctx->m_page[index]; > + if (unlikely(!page)) { > + *error = -ENOMEM; > + dev_err(&hpb->sdev_ufs_lu->sdev_dev, > + "error. cannot find page in mctx\n"); > + return 0; > + } > + > + ppn_table = page_address(page); > + if (unlikely(!ppn_table)) { > + *error = -ENOMEM; > + dev_err(&hpb->sdev_ufs_lu->sdev_dev, > + "error. cannot get ppn_table\n"); > + return 0; > + } > + > + return ppn_table[offset]; > +} > > > > >> this assumption >> is not right for all the other flash vendors - HPB entries read out >> by >> "HPB Read Buffer" >> cmd may come in Big Endian, if so, their random read performance are >> screwed. >> Actually, I have seen at least two flash vendors acting so. I had to >> modify this line >> to get the code work properly on my setups. >> >> Meanwhile, in your cover letter, you mentioned that the performance >> data >> is collected >> on a UFS2.1 device. Please re-collect the data on a real UFS3.1 >> device >> and let me >> know the part number. Otherwise, the data is not quite convincing to >> us. >> >> Regards, >> Can Guo.
| |