On Tue, Apr 23, 2019 at 08:33:47AM -0700, Bart Van Assche wrote:
> On Tue, 2019-04-23 at 18:32 +0800, Ming Lei wrote:
> > +/*
> > + * Size of integrity meta data size is usually small, 1 inline sg
> ^^^^^^^^^^^^^^
> Please change this into "metadata". Mentioning "size" twice is not
> useful.
OK
> > + * should cover normal cases.
> > + */
> > +#define SCSI_INLINE_PROT_SG_CNT 1
> > +
> > static struct kmem_cache *scsi_sdb_cache;
> > static struct kmem_cache *scsi_sense_cache;
> > static struct kmem_cache *scsi_sense_isadma_cache;
> > @@ -553,12 +559,21 @@ static void scsi_uninit_cmd(struct scsi_cmnd *cmd)
> > }
> > }
> >
> > +static inline bool scsi_prot_use_inline_sg(struct scsi_cmnd *cmd)
> > +{
> > + if (!scsi_prot_sglist(cmd))
> > + return false;
>
> Since scsi_prot_use_inline_sg() is only called if scsi_prot_sg_count() > 0,
> is the above test necessary?
Yeah, the check can be removed.
>
> > + return cmd->prot_sdb->table.sgl ==
> > + (struct scatterlist *)(cmd->prot_sdb + 1);
> > +}
> > +
> > static void scsi_mq_free_sgtables(struct scsi_cmnd *cmd)
> > {
> > if (cmd->sdb.table.nents)
> > sg_free_table_chained(&cmd->sdb.table, true);
> > - if (scsi_prot_sg_count(cmd))
> > - sg_free_table_chained(&cmd->prot_sdb->table, true);
> > + if (scsi_prot_sg_count(cmd) && !scsi_prot_use_inline_sg(cmd))
> > + sg_free_table_chained(&cmd->prot_sdb->table, false);
> > }
> >
> > static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd)
> > @@ -1044,9 +1059,11 @@ blk_status_t scsi_init_io(struct scsi_cmnd *cmd)
> > }
> >
> > ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio);
> > -
> > - if (sg_alloc_table_chained(&prot_sdb->table, ivecs,
> > - prot_sdb->table.sgl)) {
> > + if (ivecs <= SCSI_INLINE_PROT_SG_CNT)
> > + prot_sdb->table.nents = prot_sdb->table.orig_nents =
> > + SCSI_INLINE_PROT_SG_CNT;
>
> Please call sg_init_table() instead of open-coding it.
OK.
Thanks,
Ming
