On 04/22/2017 01:40 AM, Bart Van Assche wrote: > This new callback function will be used in the next patch to show > more information about SCSI requests. > > Signed-off-by: Bart Van Assche <[email protected]> > Reviewed-by: Omar Sandoval <[email protected]> > Cc: Hannes Reinecke <[email protected]> > --- > block/blk-mq-debugfs.c | 6 +++++- > include/linux/blk-mq.h | 6 ++++++ > 2 files changed, 11 insertions(+), 1 deletion(-) > > diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c > index 3a99146ece39..c5eca9245459 100644 > --- a/block/blk-mq-debugfs.c > +++ b/block/blk-mq-debugfs.c > @@ -311,6 +311,7 @@ static const char *const rqf_name[] = { > static int blk_mq_debugfs_rq_show(struct seq_file *m, void *v) > { > struct request *rq = list_entry_rq(v); > + const struct blk_mq_ops *const mq_ops = rq->q->mq_ops; > const unsigned int op = rq->cmd_flags & REQ_OP_MASK; > > seq_printf(m, "%p {.op=", rq); > @@ -324,8 +325,11 @@ static int blk_mq_debugfs_rq_show(struct seq_file *m, > void *v) > seq_puts(m, ", .rq_flags="); > blk_flags_show(m, (__force unsigned int)rq->rq_flags, rqf_name, > ARRAY_SIZE(rqf_name)); > - seq_printf(m, ", .tag=%d, .internal_tag=%d}\n", rq->tag, > + seq_printf(m, ", .tag=%d, .internal_tag=%d", rq->tag, > rq->internal_tag); > + if (mq_ops->show_rq) > + mq_ops->show_rq(m, rq); > + seq_puts(m, "}\n"); > return 0; > } > > diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h > index 0c4dadb85f62..b7bf11c05568 100644 > --- a/include/linux/blk-mq.h > +++ b/include/linux/blk-mq.h > @@ -121,6 +121,12 @@ struct blk_mq_ops { > softirq_done_fn *complete; > > /* > + * Used by the debugfs implementation to show driver-specific > + * information about a request. > + */ > + void (*show_rq)(struct seq_file *m, struct request *rq); > + > + /* > * Called when the block layer side of a hardware queue has been > * set up, allowing the driver to allocate/init matching structures. > * Ditto for exit/teardown. > I don't really like this; what does happen if someone disabled CONFIG_BLK_DEBUGFS? Won't we end up with a stale callback?
Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage [email protected] +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)
