[PATCH v2 19/25] netfs: Speed up buffered reading

[David Howells]

Eduard Zingerman <eddyz87 at gmail.com> wrote:

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