Eduard Zingerman [off-list ref] wrote:

On Fri, 2024-09-27 at 21:50 +0100, David Howells wrote:

quoted

Is it possible for you to turn on some tracepoints and access the traces?
Granted, you probably need to do the enablement during boot.

Yes, sure, tell me what you need.

If you look here:

	https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/log/?h=netfs-fixes

you can see some patches I've added.  If you can try this branch or cherry
pick:

	netfs: Fix write oops in generic/346 (9p) and generic/074 (cifs)
	netfs: Advance iterator correctly rather than jumping it
	netfs: Use a folio_queue allocation and free functions
	netfs: Add a tracepoint to log the lifespan of folio_queue structs

And then turn on the following "netfs" tracepoints:

	read,sreq,rreq,failure,write,write_iter,folio,folioq,progress,donate

which can be done by:

	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_read/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_rreq/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_sreq/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_failure/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_write/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_write_iter/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_folio/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_folioq/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_progress/enable
	echo 1 >/sys/kernel/debug/tracing/events/netfs/netfs_donate/enable

or through trace-cmd.

Alternatively I can pack this thing in a dockerfile, so that you would
be able to reproduce locally (but that would have to wait till my evening).

I don't have Docker set up, so I'm not sure how easy that would be for me to
use.

Thanks,
David