Re: [Xen-devel] [PATCH v2 2/5] xen/console: allow log level threshold adjustments

[Ian Jackson <ian.jackson@xxxxxxxxxxxxx>]

Wei Liu writes ("[PATCH v2 2/5] xen/console: allow log level threshold 
adjustments"):
> ... from serial console and via sysctl so that one doesn't always need
> to reboot to see more / less messages.
> 
> Note that upper thresholds driven from the serial console are sticky,
> i.e. while they get adjusted upwards when the lower threshold would
> otherwise end up above the upper one, they don't get adjusted when
> reducing the lower one. Full flexibility is available only via the
> sysctl interface.
> 
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
> 
> Rework the sysctl interface to pass in / out strings directly. Provide
> some helper functions to transform from log level numbers to strings and
> vice verse. Lower and upper bounds are checked. Add XSM hook.

Is this really the best way to do this ?  This is an awful lot of
hypervisor code.  Perhaps instead there should be a way to request the
table of level strings, and userspace could do the conversion ?

Or, given that this is a sysctl, so does not need a stable ABI, the
table of loglevel strings could be provided in the .h file in the form
of a suitable lifted list #define, and at runtime be implicit in the
ABI version.

Ian.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel