From: Gavin Shan <gws...@linux.vnet.ibm.com> Date: Thu, 4 May 2017 10:05:34 +1000
> On Wed, May 03, 2017 at 09:18:23AM -0400, David Miller wrote: >>From: Andrew Lunn <and...@lunn.ch> >>Date: Wed, 3 May 2017 14:47:22 +0200 >> >>> On Wed, May 03, 2017 at 02:44:37PM +1000, Gavin Shan wrote: >>>> This adds ethtool command (ETHTOOL_GNCSISTATS) to retrieve the >>>> NCSI hardware statistics. >>> >>> Hi Gavin >>> >>> I've not been following this patchset, so maybe i'm about to ask a >>> question which has already been asked and answered. >>> >>> Why cannot use just use ethtool -S for this? >> >>Indeed, when I said to use ethtool for these NCSI hw stats I meant >>that the "ethtool -S" be used, not some new ethtool command. >> > > Thanks for the comments. Feel free to ask any questions which would > make the code clear and better. There are couple of factors I thought > separate command is better than ETHTOOL_GSTATS: The statistic items from > ETHTOOL_GSTATS are variable, meaning the kernel needs provide the layout > of the statistic items via ETHTOOL_GSSET_INFO and ETHTOOL_GSTRINGS. > NCSI HW statistics aren't following this and their layout is fixed. > Besides, statistics for ETHTOOL_GSTATS are maintained in local MAC, > but NCSI HW statistics are collected from NIC on far-end. So they're > different from this point. Lastly, the NCSI software statistics needs > separate command. It'd better to have separate command for HW statistics > as well, to make things consistent. ETHTOOL_GSTATS are for device specific statistics. Whether they are fixed in your implementation or not.
