On 3/17/22 04:26, Yu Kuai wrote:
If io accounting is disabled, there is no point to handle such device
in diskstats_show(), and it can be confused for users because all fields
in iostat are zero while the disk is handling io.
Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx>
---
block/genhd.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/block/genhd.c b/block/genhd.c
index c3b32c665aec..e5307f512185 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -937,6 +937,9 @@ ssize_t part_stat_show(struct device *dev,
struct disk_stats stat;
unsigned int inflight;
+ if (!blk_queue_io_stat(q))
+ return sprintf(buf, "io accounting is disabled\n");
+
Hmm ... the above looks sub-optimal to me. Has it been considered to
return an error code instead or even better to hide the stat attribute
if I/O accounting is disabled? The latter can be achieved by modifying
disk_visible().
Thanks,
Bart.
