[ofa-general] Re: [PATCH v2] mlx4: make firmware diagnostic counters available via sysfs

[Roland Dreier]

 > The firmware diagnostic counters are not IB-protocol counters -- they are low-level
 > device-specific (i.e., ConnectX-specific) counters.

Hmm, I would disagree... things like "Responder - number of local length
errors" seem pretty close to, say, InTooBigErrors in the IP MIB.

 > If we are to implement exposing these firmware counters in the core layer, we need
 > a low-level driver API which would allow the low-level driver to pass to the core
 > layer at run time a vector of counter names, and we would then need to do all the
 > compile-time operations (DEVICE_ATTR,  declaration of all the "show functions", etc)
 > at run time.

 > It looks to me that this would be messy.  For example, each "show" method is specific to
 > one counter-name "file".  We would then need to pre-declare (at compile time) a group
 > of "show" methods whose names are the offsets, rather than the counter-name
 > (e.g., device_name ## "counter-1", etc.), and this would have the effect of limiting
 > the max number of counters we could generate.

this would be not too hard to implement in the same way as "ethtool -S"
does it I guess.

but I'm not keen on sticking a bunch of cryptic hardware-device-specific
junk in sysfs.

 - R.