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 collecting 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 return 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().    Attaching  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>