On 09/28/2018 02:27 PM, Leonard Crestez wrote:
> On Fri, 2018-09-28 at 10:28 -0700, Eric Dumazet wrote:
>> In the recent TCP/EDT patch series, I switched TCP and sch_fq
>> clocks from MONOTONIC to TAI, in order to meet the choice done
>> earlier for sch_etf packet scheduler.
>>
>> But sure enough, this broke some setups were the TAI clock
>> jumps forward (by almost 50 year...), as reported
>> by Leonard Crestez.
>>
>> If we want to converge later, we'll probably need to add
>> an skb field to differentiate the clock bases, or a socket option.
>>
>> In the meantime, an UDP application will need to use CLOCK_MONOTONIC
>> base for its SCM_TXTIME timestamps if using fq packet scheduler.
>>
>> Fixes: 72b0094f9182 ("tcp: switch tcp_clock_ns() to CLOCK_TAI base")
>> Fixes: 142537e41923 ("net_sched: sch_fq: switch to CLOCK_TAI")
>> Fixes: fd2bca2aa789 ("tcp: switch internal pacing timer to CLOCK_TAI")
>> Signed-off-by: Eric Dumazet <eduma...@google.com>
>> Reported-by: Leonard Crestez <leonard.cres...@nxp.com>
>
> Tested-by: Leonard Crestez <leonard.cres...@nxp.com>
>
> Fixes the problem reported earlier when applied on top of next-20180928
>
Thanks again ;)
