KTR_SPAREx

[Dag-Erling Smørgrav]

Konstantin Belousov <kostikbel at gmail.com> writes:
> Moving all device drivers to KTR_DEV makes the KTR unusable for device
> driver debugging. When looking at the drm2 and gem traces, I do not want
> to see other devices tracepoints. Amount of data from GEM is huge, and
> obfuscating it with unrelated debugging recycles the ktr ring faster, aside
> of making noise that cayses log to be meaningless.

We only have a limited number of KTR types - 32, to be precise.  We
can't spare one for each driver, and there's no reason why *your* driver
(for any value of "you") should get its own while everybody else shares
KTR_DEV.

If you think KTR_DEV is too noisy, add sysctls to enable or disable
tracing on a per-device basis.  It should be quite easy to generalize.

(I still haven't gotten around to implementing a similar infrastructure
for network interfaces...)

DES
-- 
Dag-Erling Smørgrav - des at des.no