Seymour, Shane M 05545c92db st: implement tape statistics
This patch implements tape statistics in the st module via
sysfs. Current no statistics are available for tape I/O and there
is no easy way to reuse the block layer statistics for tape
as tape is a character device and does not have perform I/O in
sector sized chunks (the size of the data written to tape
can change). For tapes we also need extra stats related to
things like tape movement (via other I/O).

There have been multiple end users requesting statistics
including AT&T (and some HP customers who have not given
permission to be named). It is impossible for them
to investigate any issues related to tape performance
in a non-invasive way.

[jejb: eliminate PRId64]
Signed-off-by: Shane Seymour <shane.seymour@hp.com>
Tested-by: Shane Seymour <shane.seymour@hp.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
2015-06-02 08:03:25 -07:00
..
2015-04-17 09:04:09 -04:00
2015-02-11 10:28:45 -08:00
2015-04-27 10:10:19 -07:00
2015-04-27 10:10:19 -07:00
2015-04-27 10:04:39 -07:00
2015-04-27 10:04:39 -07:00
2015-04-27 10:05:55 -07:00
2015-04-27 10:05:55 -07:00
2014-12-04 09:57:13 +01:00
2015-04-17 10:13:56 -07:00
2014-11-20 09:11:11 +01:00
2014-07-17 22:07:37 +02:00
2014-11-20 09:11:10 +01:00
2014-11-20 09:11:10 +01:00
2014-11-24 16:13:16 +01:00
2014-11-20 09:11:10 +01:00
2015-05-31 17:47:31 -07:00
2015-05-31 17:48:35 -07:00
2015-05-31 17:47:31 -07:00
2015-04-16 19:02:04 -04:00
2015-04-09 14:19:23 -07:00
2014-07-17 22:07:35 +02:00
2014-11-24 20:01:28 +01:00
2014-11-20 09:11:10 +01:00
2014-11-20 09:11:10 +01:00
2014-07-17 22:07:37 +02:00
2015-04-16 10:37:12 -07:00
2015-05-25 08:46:24 -07:00
2014-11-12 11:15:57 +01:00
2015-01-09 15:44:19 +01:00
2015-04-11 22:27:14 -04:00
2014-07-17 22:07:39 +02:00
2014-11-24 20:01:28 +01:00
2014-11-12 11:15:57 +01:00
2015-06-02 08:03:25 -07:00
2015-06-02 08:03:25 -07:00
2014-11-20 09:11:15 +01:00
2014-11-20 09:11:10 +01:00
2014-11-20 09:11:10 +01:00