| Message ID | 20170411205842.28137-6-bart.vanassche@sandisk.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Apr 11, 2017 at 01:58:41PM -0700, 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 <bart.vanassche@sandisk.com> > Cc: Omar Sandoval <osandov@fb.com> > Cc: Hannes Reinecke <hare@suse.com> > --- > block/blk-mq-debugfs.c | 10 ++++++++-- > include/linux/blk-mq.h | 6 ++++++ > 2 files changed, 14 insertions(+), 2 deletions(-) > > diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c > index 161f30fc236f..6b28d92d4c0e 100644 > --- a/block/blk-mq-debugfs.c > +++ b/block/blk-mq-debugfs.c > @@ -316,7 +316,9 @@ 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; > + char drv_info[200]; > > seq_printf(m, "%p {.op=", rq); > if (op < ARRAY_SIZE(op_name) && op_name[op]) > @@ -329,8 +331,12 @@ 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, > - rq->internal_tag); > + if (mq_ops->show_rq) > + mq_ops->show_rq(rq, drv_info, sizeof(drv_info)); How about passing the seq_file to the callback instead of this arbitrarily-sized on-stack buffer?
On Thu, 2017-04-13 at 16:21 -0700, Omar Sandoval wrote: > How about passing the seq_file to the callback instead of this > arbitrarily-sized on-stack buffer? Hello Omar, That sounds like a good idea to me. I will make that change. Bart.
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 161f30fc236f..6b28d92d4c0e 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -316,7 +316,9 @@ 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; + char drv_info[200]; seq_printf(m, "%p {.op=", rq); if (op < ARRAY_SIZE(op_name) && op_name[op]) @@ -329,8 +331,12 @@ 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, - rq->internal_tag); + if (mq_ops->show_rq) + mq_ops->show_rq(rq, drv_info, sizeof(drv_info)); + else + drv_info[0] = '\0'; + seq_printf(m, ", .tag=%d, .internal_tag=%d%s%s}\n", rq->tag, + rq->internal_tag, drv_info[0] ? ", " : "", drv_info); return 0; } diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index dea255dee359..de2a1c2ddd84 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -120,6 +120,12 @@ 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 request *rq, char *info, unsigned int info_sz); + + /* * 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.
This new callback function will be used in the next patch to show more information about SCSI requests. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Omar Sandoval <osandov@fb.com> Cc: Hannes Reinecke <hare@suse.com> --- block/blk-mq-debugfs.c | 10 ++++++++-- include/linux/blk-mq.h | 6 ++++++ 2 files changed, 14 insertions(+), 2 deletions(-)