On Tuesday 29 April 2008 19:48, Roland Dreier wrote: > given that mthca has had the old interface for nearly a year and a half, > what do we gain from changing it now? > We gain clarity and consistency. The mlx4 driver in OFED 1.3 uses log values in the module parameters (patch for mlx4 that I submitted in October 2007).
> > I put a check in the patch for detecting if the user specified a log or > not, > > to make the transition from the old method (of numbers instead of logs) > > easier. > > Yes, that is nice. Would the plan be just to allow both methods? Good idea, but cannot be done for all parameters. "max rdb per qp" is by default 4 rdb's per qp (log = 2). If an administrator supplies ONLY this parameter in an "options" line for ib_mthca, how can I tell if the value is a log or a number? (Say administrator places the following line: "options ib_mthca num_rdb=4" -- how will I know that the admin means "log" , or just a number). Maybe the best solution is to change the parameter name from "num_xxx" to "log_num_xxx". That way, if the administrator is using an old /etc/modprobe.conf file, with lines like "options ib_mthca num_xxxx=20000", then ib_mthca will fail to load, and there will be lines in file /var/log/messages like "ib_mthca: Unknown parameter `num_cq' ". Please note also that very few customer are using this module-parameter capability as yet. > it would make sense for mlx4 to allow setting parameter > values by value and not by log, and then we end up with all the same > code in both places, and so why not just have mlx4 set by value the same > way as mthca? > OFED 1.3 has the patch I submitted for mlx4 in October 07, and this already uses logs, not values. We would then be confusing Hermon customers if we change this to values. I think it is healthiest to: 1. Use the ib_mthca patch I submitted, but change the parameter names from "num_xxx" to "log_num_xxx" 2. Take the mlx4 patch as is (maybe adding a check that values are <31). - Jack _______________________________________________ general mailing list [email protected] http://lists.openfabrics.org/cgi-bin/mailman/listinfo/general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
