mlx5dv_get_clock_info(3) — Linux manual page


MLX5DV_GET_CLOCK_INFO(3)  Library Functions Manual  MLX5DV_GET_CLOCK_INFO(3)

NAME         top

       mlx5dv_get_clock_info - Get device clock information

SYNOPSIS         top

       #include <infiniband/mlx5dv.h>

       int mlx5dv_get_clock_info(struct ibv_context *ctx_in,
                                 struct mlx5dv_clock_info *clock_info);

DESCRIPTION         top

       Get the updated core clock_info from the device driver. This
       information will be used later to translate the completion timestamp
       from HCA core clock to nanoseconds. The values of the clock are
       updated from the driver's PTP clock, therefore, without a running PTP
       client on the machine, the wall clock conversion will not be

       Pass the latest struct mlx5dv_clock_info to mlx5dv_ts_to_ns(3) in
       order to translate the completion timestamp from HCA core clock to

       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)

RETURN VALUE         top

       0 on success or the value of errno on failure (which indicates the
       failure reason).

SEE ALSO         top

       mlx5dv(7), mlx5dv_ts_to_ns(3)

AUTHORS         top

       Feras Daoud <>

COLOPHON         top

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1.0.0                            2017-11-08         MLX5DV_GET_CLOCK_INFO(3)

Pages that refer to this page: mlx5dv_get_clock_info(3)mlx5dv_ts_to_ns(3)