Files
epics-base/src/ca/flow_control.cpp
2000-04-28 01:29:00 +00:00

77 lines
1.5 KiB
C++

/* $Id$ */
/*
*
* L O S A L A M O S
* Los Alamos National Laboratory
* Los Alamos, New Mexico 87545
*
* Copyright, 1986, The Regents of the University of California.
*
* Author: Jeff Hill
*/
#include "iocinf.h"
/*
* FLOW CONTROL
*
* Keep track of how many times messages have
* come with out a break in between and
* suppress monitors if we are behind
* (an update is sent when we catch up)
*/
void flow_control_on (tcpiiu *piiu)
{
int status;
LOCK (piiu->pcas);
/*
* I prefer to avoid going into flow control
* as this impacts the performance of batched fetches
*/
if (piiu->contiguous_msg_count >= MAX_CONTIGUOUS_MSG_COUNT) {
if (!piiu->client_busy) {
status = piiu->busyRequestMsg ();
if (status==ECA_NORMAL) {
assert(piiu->pcas->ca_number_iiu_in_fc<UINT_MAX);
piiu->pcas->ca_number_iiu_in_fc++;
piiu->client_busy = TRUE;
# if defined(DEBUG)
printf("fc on\n");
# endif
}
}
}
else {
piiu->contiguous_msg_count++;
}
UNLOCK (piiu->pcas);
return;
}
void flow_control_off (tcpiiu *piiu)
{
int status;
LOCK (piiu->pcas);
piiu->contiguous_msg_count = 0;
if (piiu->client_busy) {
status = piiu->readyRequestMsg ();
if (status==ECA_NORMAL) {
assert (piiu->pcas->ca_number_iiu_in_fc>0u);
piiu->pcas->ca_number_iiu_in_fc--;
piiu->client_busy = FALSE;
# if defined(DEBUG)
printf("fc off\n");
# endif
}
}
UNLOCK (piiu->pcas);
return;
}