Specifications

64 CBI Buffer Formats HighWire MTP-2 - 1.2, September 4, 2002
6-3-7. CBI_M2_CREDIT L3 sends this message to L2 to inform L2 that L3 has completed processing a
number of received messages. This message allows L2 to release buffers
back to the MTP2 buffer pool and acts as receive-side flow control.
L3 must ensure that it sends the CBI_M2_CREDIT message to L2 with
sufficient frequency to avoid emptying the MTP2 buffer pool.
There is no response to this message unless the number of buffers specified
is larger than the number of buffers received (see Section 6-3-8,
“CBI_M2_CREDIT_ERROR”).
Data structure.
typedef struct cbi_m2_credit
{
CBI_IPS ips_hdr;
CBI_ULONG num_msgs;
} CBI_M2_CREDIT;
Parameters.
ips_hdr
IPS header. For definition, see Section 6-1-1. The following fields are specified
below:
ips_type
ips_typeips_type
ips_type - IPS_CBI_M2_CREDIT.
sender_handle
sender_handlesender_handle
sender_handle - L3’s handle for the join for this link.
receiver_handle
receiver_handlereceiver_handle
receiver_handle - L2’s handle for the join for this link.
num_msgs
This field informs L2 how many messages have been completely processed
since the last credit message was sent. It is the number of buffers to be
released back to the buffer pool.