On Fri, Jun 26, 2020 at 2:41 AM Olivier Matz <olivier.m...@6wind.com> wrote: > Should mlx5dv_get_clock_info() be called for each convesion? In the man > page [1], we can read this: > > If the clock_info becomes too old then time conversion will return > wrong conversion results. The user must ensure that > mlx5dv_get_clock_info(3) is called at least once every > max_clock_info_update_nsec as returned by the mlx5dv_query_device(3) > function. > > I understand this as mlx5dv_get_clock_info() being slower than > mlx5dv_ts_to_ns(), and should not be called for each packet.
Right. I plan to use rte_timer (like in drivers/net/ena/) to query clock info periodically. > > I suppose that when rdma-core library does a conversion to nanosec, it > takes in account the fact that system and device are not synchronized > (are they?). PTP daemon like linuxptp is in charge of syncing both device and system clocks with external master. Thanks. PK
