NAME

       ibv_attach_counters_point_flow - attach individual counter definition to a flow object

SYNOPSIS

              #include <infiniband/verbs.h>

              int ibv_attach_counters_point_flow(struct ibv_counters *counters,
                                                 struct ibv_counter_attach_attr *counter_attach_attr,
                                                 struct ibv_flow *flow);

DESCRIPTION

       Attach  counters point are a family of APIs to attach individual counter description definition to a verb
       object at a specific index location.

       Counters object will start collecting values after it is bound to the verb object resource.

       A static attach can be created when NULL is provided instead of the reference to the verbs object  (e.g.:
       in case of flow providing NULL instead of flow).  In this case, this counters object will only start col‐
       lecting  values  after  it is bound to the verbs resource, for flow this is when referencing the counters
       handle when creating a flow with ibv_create_flow().

       Once an ibv_counters is bound statically to a verbs resource, no additional attach is  allowed  till  the
       counter object is not bound to any verb object.

       The argument counter_desc specifies which counter value should be collected.  It is defined in verbs.h as
       one of the enum ibv_counter_description options.

       Supported capabilities of specific counter_desc values per verbs object can be tested by checking the re‐
       turn value for success or ENOTSUP errno.

       Attaching a counters handle to multiple objects of the same type will accumulate the values into a single
       index.  e.g.: creating several ibv_flow(s) with the same ibv_counters handle will collect the values from
       all  relevant  flows  into  the relevant index location when reading the values from ibv_read_counters(),
       setting the index more than once with different or same counter_desc will aggregate the values  from  all
       relevant counters into the relevant index location.

       The runtime values of counters can be read from the hardware by calling ibv_read_counters().

ARGUMENTS

       counters
              Existing counters to attach new counter point on.

       counter_attach_attr
              An ibv_counter_attach_attr struct, as defined in verbs.h.

       flow   Existing flow to attach a new counters point on (in static mode it must be NULL).

   counter_attach_attr Argument
              struct ibv_counter_attach_attr {
                  enum ibv_counter_description counter_desc;
                  uint32_t index;
                  uint32_t comp_mask;
              };

   counter_desc Argument
              enum ibv_counter_description {
                  IBV_COUNTER_PACKETS,
                  IBV_COUNTER_BYTES,
              };

       index  Desired location of the specific counter at the counters object.

       comp_mask
              Bitmask specifying what fields in the structure are valid.

RETURN VALUE

       ibv_attach_counters_point_flow()  returns 0 on success, or the value of errno on failure (which indicates
       the failure reason)

ERRORS

       EINVAL invalid argument(s) passed

       ENOTSUP
              counter_desc is not supported on the requested object

       EBUSY  the counter object is already bound to a flow, additional attach calls is not allowed  (valid  for
              static attach only)

       ENOMEM not enough memory

NOTES

       Counter  values in each index location are cleared upon creation when calling ibv_create_counters().  At‐
       taching counters points will only increase these values accordingly.

EXAMPLE

       An example of use of ibv_attach_counters_point_flow() is shown in ibv_read_counters

SEE ALSO

       ibv_create_counters, ibv_destroy_counters, ibv_read_counters, ibv_create_flow

AUTHORS

       Raed Salem <raeds@mellanox.com>

       Alex Rosenbaum <alexr@mellanox.com>

libibverbs                                         2018-04-02                  ibv_attach_counters_point_flow(3)