Re: [PATCH iproute2] etf: make printing of variable JSON friendly

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue, 23 Jul 2019 21:34:46 +0000
"Patel, Vedang" <vedang.patel@intel.com> wrote:

> > On Jul 22, 2019, at 5:11 PM, David Ahern <dsahern@gmail.com> wrote:
> > 
> > On 7/22/19 1:11 PM, Patel, Vedang wrote:  
> >> 
> >>   
> >>> On Jul 22, 2019, at 11:21 AM, David Ahern <dsahern@gmail.com> wrote:
> >>> 
> >>> On 7/19/19 3:40 PM, Vedang Patel wrote:  
> >>>> In iproute2 txtime-assist series, it was pointed out that print_bool()
> >>>> should be used to print binary values. This is to make it JSON friendly.
> >>>> 
> >>>> So, make the corresponding changes in ETF.
> >>>> 
> >>>> Fixes: 8ccd49383cdc ("etf: Add skip_sock_check")
> >>>> Reported-by: Stephen Hemminger <stephen@networkplumber.org>
> >>>> Signed-off-by: Vedang Patel <vedang.patel@intel.com>
> >>>> ---
> >>>> tc/q_etf.c | 12 ++++++------
> >>>> 1 file changed, 6 insertions(+), 6 deletions(-)
> >>>> 
> >>>> diff --git a/tc/q_etf.c b/tc/q_etf.c
> >>>> index c2090589bc64..307c50eed48b 100644
> >>>> --- a/tc/q_etf.c
> >>>> +++ b/tc/q_etf.c
> >>>> @@ -176,12 +176,12 @@ static int etf_print_opt(struct qdisc_util *qu, FILE *f, struct rtattr *opt)
> >>>> 		     get_clock_name(qopt->clockid));
> >>>> 
> >>>> 	print_uint(PRINT_ANY, "delta", "delta %d ", qopt->delta);
> >>>> -	print_string(PRINT_ANY, "offload", "offload %s ",
> >>>> -				(qopt->flags & TC_ETF_OFFLOAD_ON) ? "on" : "off");
> >>>> -	print_string(PRINT_ANY, "deadline_mode", "deadline_mode %s ",
> >>>> -				(qopt->flags & TC_ETF_DEADLINE_MODE_ON) ? "on" : "off");
> >>>> -	print_string(PRINT_ANY, "skip_sock_check", "skip_sock_check %s",
> >>>> -				(qopt->flags & TC_ETF_SKIP_SOCK_CHECK) ? "on" : "off");
> >>>> +	if (qopt->flags & TC_ETF_OFFLOAD_ON)
> >>>> +		print_bool(PRINT_ANY, "offload", "offload ", true);
> >>>> +	if (qopt->flags & TC_ETF_DEADLINE_MODE_ON)
> >>>> +		print_bool(PRINT_ANY, "deadline_mode", "deadline_mode ", true);
> >>>> +	if (qopt->flags & TC_ETF_SKIP_SOCK_CHECK)
> >>>> +		print_bool(PRINT_ANY, "skip_sock_check", "skip_sock_check", true);
> >>>> 
> >>>> 	return 0;
> >>>> }
> >>>>   
> >>> 
> >>> This changes existing output for TC_ETF_OFFLOAD_ON and
> >>> TC_ETF_DEADLINE_MODE_ON which were added a year ago.  
> >> Yes, this is a good point. I missed that. 
> >> 
> >> Another idea is to use is_json_context() and call print_bool() there. But, that will still change values corresponding to the json output for the above flags from “on”/“off” to “true”/“false”. I am not sure if this is a big issue. 
> >> 
> >> My suggestion is to keep the code as is. what do you think?
> >>   
> > 
> > I think we need automated checkers for new code. ;-)
> > 
> > The first 2 should not change for backward compatibility - unless there
> > is agreement that this feature is too new and long term it is better to
> > print as above.
> > 
> > Then the new one should follow context of the other 2 - consistency IMHO
> > takes precedence.  
> Thanks for the inputs. 
> 
> Let’s keep whatever is currently present upstream and you can ignore this patch.
> 
> Thanks,
> Vedang
Agreed. At this point consistency is better.
Maybe at some future point, all the JSON will be reviewed and fixed (yes it would be a breaking flag day).
But for now inconsistent usage across ip, tc, and devlink is a fact of life.