b0d97557eb
The inflight of partition 0 doesn't include inflight IOs to all
sub-partitions, since currently mq calculates inflight of specific
partition by simply camparing the value of the partition pointer.
Thus the following case is possible:
$ cat /sys/block/vda/inflight
0 0
$ cat /sys/block/vda/vda1/inflight
0 128
While single queue device (on a previous version, e.g. v3.10) has no
this issue:
$cat /sys/block/sda/sda3/inflight
0 33
$cat /sys/block/sda/inflight
0 33
Partition 0 should be specially handled since it represents the whole
disk. This issue is introduced since commit bf0ddaba65dd ("blk-mq: fix
sysfs inflight counter").
Besides, this patch can also fix the inflight statistics of part 0 in
/proc/diskstats. Before this patch, the inflight statistics of part 0
doesn't include that of sub partitions. (I have marked the 'inflight'
field with asterisk.)
$cat /proc/diskstats
259 0 nvme0n1 45974469 0 367814768 6445794 1 0 1 0 *0* 111062 6445794 0 0 0 0 0 0
259 2 nvme0n1p1 45974058 0 367797952 6445727 0 0 0 0 *33* 111001 6445727 0 0 0 0 0 0
This is introduced since commit f299b7c7a9de ("blk-mq: provide internal
in-flight variant").
Fixes: bf0ddaba65dd ("blk-mq: fix sysfs inflight counter")
Fixes: f299b7c7a9de ("blk-mq: provide internal in-flight variant")
Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[axboe: adapt for 5.11 partition change]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.