Re: stalling IO regression since linux 5.12, through 5.18

From: Chris Murphy
Date: Wed Aug 17 2022 - 12:35:17 EST




On Wed, Aug 17, 2022, at 11:34 AM, Ming Lei wrote:

> From the 2nd log of blockdebugfs-all.txt, still not see any in-flight IO on
> request based block devices, but sda is _not_ included in this log, and
> only sdi, sdg and sdf are collected, is that expected?

While the problem was happening I did

cd /sys/kernel/debug/block
find . -type f -exec grep -aH . {} \;

The file has the nodes out of order, but I don't know enough about the interface to see if there are things that are missing, or what it means.


> BTW, all request based block devices should be observed in blk-mq debugfs.

/sys/kernel/debug/block contains

drwxr-xr-x. 2 root root 0 Aug 17 15:20 md0
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sda
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdb
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdc
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdd
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sde
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdf
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdg
drwxr-xr-x. 51 root root 0 Aug 17 15:20 sdh
drwxr-xr-x. 4 root root 0 Aug 17 15:20 sdi
drwxr-xr-x. 2 root root 0 Aug 17 15:20 zram0


--
Chris Murphy