On Tue, Feb 13, 2018 at 03:17:31PM -0800, Darrick J. Wong wrote:

On Tue, Feb 13, 2018 at 08:21:06AM +1100, Dave Chinner wrote:

quoted

On Mon, Feb 12, 2018 at 10:29:48AM -0800, Darrick J. Wong wrote:

quoted

On Mon, Feb 12, 2018 at 02:00:05PM +0100, Carlos Maiolino wrote:

quoted

Remove unused legacy btree traces from IRIX era.

Signed-off-by: Carlos Maiolino <redacted>
---

Talking to Dave about it, he mentioned XFS_BTREE_TRACE_CURSOR might be worth to
turn into a proper ftrace trace point, so I didn't touch _CURSOR traces in this
patchset, and a proper conversion will be sent later, unless it's not worth at
all, and I should send a V2 also removing TRACE_CURSOR.

TBH I wonder the opposite -- why not turn all of these into tracepoints?

TBH, we haven't used them in at least 15 years. What value do they
provide apart from making the traces even noisier (and potentially
more lossy) than they already are?

FWIW adding trace_printks to some of those functions was rather useful
for checking that the unusual refcount and rmap btree semantics actually
resulted in calls to the desired btree functions.  I wish I'd cleaned up
that debugging patch and sent it, but it's lost now.

Ok, so the non-cursor traces would have been useful to you.
That's fine - I just don't want to add stuff that doesn't have any
specific use because it's already hard enough to filter traces down
to just the things we need to see....

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com