99 lines
2.2 KiB
C
99 lines
2.2 KiB
C
/************************************************************************/
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/* */
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/* L O S A L A M O S */
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/* Los Alamos National Laboratory */
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/* Los Alamos, New Mexico 87545 */
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/* */
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/* Copyright, 1986, The Regents of the University of California. */
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/* */
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/* */
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/* History */
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/* ------- */
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/* 06xx89 joh First Release */
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/* 060591 joh delinting */
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/* */
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/*_begin */
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/************************************************************************/
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/* */
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/* Title: IOC network flow control module */
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/* File: atcs:[ca]flow_control.c */
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/* Environment: VMS. UNIX, VRTX */
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/* Equipment: VAX, SUN, VME */
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/* */
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/* */
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/* Purpose */
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/* ------- */
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/* */
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/* ioc flow control module */
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/* */
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/* */
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/* Special comments */
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/* ------- -------- */
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/* */
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/************************************************************************/
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/*_end */
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static char *sccsId = "@(#) $Id$";
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#include "iocinf.h"
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/*
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* FLOW CONTROL
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*
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* Keep track of how many times messages have
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* come with out a break in between and
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* suppress monitors if we are behind
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* (an update is sent when we catch up)
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*/
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void flow_control(struct ioc_in_use *piiu)
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{
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unsigned nbytes;
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int status;
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LOCK;
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/*
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* use of the additional system call here does not
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* seem to slow things down appreciably
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*/
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status = socket_ioctl(piiu->sock_chan,
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FIONREAD,
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&nbytes);
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if (status < 0) {
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TAG_CONN_DOWN(piiu);
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UNLOCK;
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return;
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}
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/*
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* I wish to avoid going into flow control however
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* as this impacts the performance of batched fetches
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*/
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if (nbytes) {
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piiu->contiguous_msg_count++;
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if (!piiu->client_busy)
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if (piiu->contiguous_msg_count >
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MAX_CONTIGUOUS_MSG_COUNT) {
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piiu->client_busy = TRUE;
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ca_busy_message(piiu);
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# if defined(DEBUG)
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printf("fc on\n");
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# endif
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}
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} else {
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piiu->contiguous_msg_count = 0;
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if (piiu->client_busy) {
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# if defined(DEBUG)
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printf("fc off\n");
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# endif
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ca_ready_message(piiu);
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piiu->client_busy = FALSE;
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}
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}
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UNLOCK;
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return;
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}
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