2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 /* rx_user.c contains routines specific to the user space UNIX implementation of rx */
12 # include <afs/param.h>
13 # include <sys/types.h> /* fd_set on older platforms */
17 # include <winsock2.h>
19 # include <unistd.h> /* select() prototype */
20 # include <sys/time.h> /* struct timeval, select() prototype */
22 # include <sys/select.h> /* fd_set on newer platforms */
24 # include <sys/socket.h>
25 # include <sys/file.h>
27 # include <sys/stat.h>
28 # include <netinet/in.h>
30 # include <sys/ioctl.h>
31 # include <sys/time.h>
34 # include "rx_globals.h"
37 #define MAXTHREADNAMELENGTH 64
39 int debugSelectFailure; /* # of times select failed */
41 * Sleep on the unique wait channel provided.
43 void rxi_Sleep(void *addr)
45 LWP_WaitProcess(addr);
49 * Wakeup any threads on the channel provided.
50 * They may be woken up spuriously, and must check any conditions.
52 void rxi_Wakeup(void *addr)
54 LWP_NoYieldSignal(addr);
57 PROCESS rx_listenerPid; /* LWP process id of socket listener process */
58 static void rx_ListenerProc(void *dummy);
61 * Delay the current thread the specified number of seconds.
63 void rxi_Delay(int sec)
68 static int quitListening = 0;
70 /* This routine will kill the listener thread, if it exists. */
75 rxi_ReScheduleEvents();
78 /* This routine will get called by the event package whenever a new,
79 earlier than others, event is posted. If the Listener process
80 is blocked in selects, this will unblock it. It also can be called
81 to force a new trip through the rxi_Listener select loop when the set
82 of file descriptors it should be listening to changes... */
83 void rxi_ReScheduleEvents() {
84 if (rx_listenerPid) IOMGR_Cancel(rx_listenerPid);
87 void rxi_InitializeThreadSupport(void)
91 LWP_InitializeProcessSupport(LWP_NORMAL_PRIORITY, &junk);
93 FD_ZERO(&rx_selectMask);
96 void rxi_StartServerProc(proc, stacksize)
100 LWP_CreateProcess(proc, stacksize, RX_PROCESS_PRIORITY,
101 0, "rx_ServerProc", &scratchPid);
104 void rxi_StartListener() {
105 /* Priority of listener should be high, so it can keep conns alive */
106 #define RX_LIST_STACK 24000
107 LWP_CreateProcess(rx_ListenerProc, RX_LIST_STACK, LWP_MAX_PRIORITY, 0,
108 "rx_Listener", &rx_listenerPid);
111 /* The main loop which listens to the net for datagrams, and handles timeouts
112 and retransmissions, etc. It also is responsible for scheduling the
113 execution of pending events (in conjunction with event.c).
115 Note interaction of nextPollTime and lastPollWorked. The idea is that if rx is not
116 keeping up with the incoming stream of packets (because there are threads that
117 are interfering with its running sufficiently often), rx does a polling select
118 before doing a real IOMGR_Select system call. Doing a real select means that
119 we don't have to let other processes run before processing more packets.
121 So, our algorithm is that if the last poll on the file descriptor found useful data, or
122 we're at the time nextPollTime (which is advanced so that it occurs every 3 or 4 seconds),
123 then we try the polling select before the IOMGR_Select. If we eventually catch up
124 (which we can tell by the polling select returning no input packets ready), then we
125 don't do a polling select again until several seconds later (via nextPollTime mechanism).
128 void rxi_ListenerProc(rfds, tnop, newcallp)
131 struct rx_call **newcallp;
135 register struct rx_packet *p = (struct rx_packet *)0;
138 afs_int32 nextPollTime; /* time to next poll FD before sleeping */
139 int lastPollWorked, doingPoll; /* true iff last poll was useful */
140 struct timeval tv, *tvp;
143 char name[MAXTHREADNAMELENGTH] = "srv_0";
148 code = LWP_CurrentProcess(&pid);
150 fprintf(stderr, "rxi_Listener: Can't get my pid.\n");
153 rx_listenerPid = pid;
154 swapthreadname(pid, "listener", &name);
157 /* Grab a new packet only if necessary (otherwise re-use the old one) */
159 rxi_RestoreDataBufs(p);
162 if (!(p = rxi_AllocPacket(RX_PACKET_CLASS_RECEIVE)))
163 osi_Panic("rxi_ListenerProc: no packets!"); /* Shouldn't happen */
165 /* Wait for the next event time or a packet to arrive. */
166 /* event_RaiseEvents schedules any events whose time has come and
167 then atomically computes the time to the next event, guaranteeing
168 that this is positive. If there is no next event, it returns 0 */
170 if (!rxevent_RaiseEvents(&cv)) tvp = (struct timeval *) 0;
172 /* It's important to copy cv to tv, because the 4.3 documentation
173 for select threatens that *tv may be updated after a select, in
174 future editions of the system, to indicate how much of the time
175 period has elapsed. So we shouldn't rely on tv not being altered. */
176 tv.tv_sec = cv.sec; /* Time to next event */
177 tv.tv_usec = cv.usec;
182 *rfds = rx_selectMask;
184 if (lastPollWorked || nextPollTime < clock_Sec()) {
185 /* we're catching up, or haven't tried to for a few seconds */
187 nextPollTime = clock_Sec() + 4; /* try again in 4 seconds no matter what */
188 tv.tv_sec = tv.tv_usec = 0; /* make sure we poll */
190 code = select(rx_maxSocketNumber+1, rfds, 0, 0, tvp);
194 code = IOMGR_Select(rx_maxSocketNumber+1, rfds, 0, 0, tvp);
196 lastPollWorked = 0; /* default is that it didn't find anything */
200 LWP_DestroyProcess(pid);
206 * If it was a timer interrupt then we can assume that
207 * the time has advanced by roughly the value of the
208 * previous timeout, and that there is now at least
214 /* select or IOMGR_Select returned failure */
215 debugSelectFailure++; /* update debugging counter */
220 * IOMGR_Cancel is invoked whenever a new event is
221 * posted that is earlier than any existing events.
222 * So we re-evaluate the time, and then go back to
229 /* Packets have arrived, presumably:
230 * If it wasn't a timer interrupt, then no event should have
231 * timed out yet (well some event may have, but only just...), so
232 * we don't bother looking to see if any have timed out, but just
233 * go directly to reading the data packets
236 if (doingPoll) lastPollWorked = 1;
238 for (i=0; p && i<rfds->fd_count; i++) {
239 socket = rfds->fd_array[i];
240 if (rxi_ReadPacket(socket, p, &host, &port)) {
242 p = rxi_ReceivePacket(p, socket, host, port,
244 if (newcallp && *newcallp) {
253 for (socket = rx_minSocketNumber;
254 p && socket <= rx_maxSocketNumber; socket++) {
255 if (!FD_ISSET(socket, rfds))
257 if (rxi_ReadPacket(socket, p, &host, &port)) {
258 p = rxi_ReceivePacket(p, socket, host, port,
260 if (newcallp && *newcallp) {
275 /* This is the listener process request loop. The listener process loop
276 * becomes a server thread when rxi_ListenerProc returns, and stays
277 * server thread until rxi_ServerProc returns. */
278 static void rx_ListenerProc(void *dummy)
282 struct rx_call *newcall;
285 if (!(rfds = IOMGR_AllocFDSet())) {
286 osi_Panic("rx_ListenerProc: no fd_sets!\n");
292 rxi_ListenerProc(rfds, &threadID, &newcall);
293 /* assert(threadID != -1); */
294 /* assert(newcall != NULL); */
295 sock = OSI_NULLSOCKET;
296 rxi_ServerProc(threadID, newcall, &sock);
297 /* assert(sock != OSI_NULLSOCKET); */
302 /* This is the server process request loop. The server process loop
303 * becomes a listener thread when rxi_ServerProc returns, and stays
304 * listener thread until rxi_ListenerProc returns. */
309 struct rx_call *newcall = NULL;
312 if (!(rfds = IOMGR_AllocFDSet())) {
313 osi_Panic("rxi_ListenerProc: no fd_sets!\n");
316 rxi_MorePackets(rx_maxReceiveWindow+2); /* alloc more packets */
317 rxi_dataQuota += rx_initSendWindow; /* Reserve some pkts for hard times */
318 /* threadID is used for making decisions in GetCall. Get it by bumping
319 * number of threads handling incoming calls */
320 threadID = rxi_availProcs++;
323 sock = OSI_NULLSOCKET;
324 rxi_ServerProc(threadID, newcall, &sock);
325 /* assert(sock != OSI_NULLSOCKET); */
327 rxi_ListenerProc(rfds, &threadID, &newcall);
328 /* assert(threadID != -1); */
329 /* assert(newcall != NULL); */
335 * Called from GetUDPSocket.
336 * Called from a single thread at startup.
337 * Returns 0 on success; -1 on failure.
344 * Put the socket into non-blocking mode so that rx_Listener
345 * can do a polling read before entering select
347 if (fcntl(sock, F_SETFL, FNDELAY) == -1) {
349 (osi_Msg "rxi_Listen: unable to set non-blocking mode on socket\n");
353 if (sock > FD_SETSIZE-1) {
354 (osi_Msg "rxi_Listen: socket descriptor > (FD_SETSIZE-1) = %d\n",
360 FD_SET(sock, &rx_selectMask);
361 if (sock > rx_maxSocketNumber) rx_maxSocketNumber = sock;
362 if (sock < rx_minSocketNumber) rx_minSocketNumber = sock;
369 int rxi_Recvmsg(osi_socket socket, struct msghdr *msg_p, int flags)
371 return recvmsg((int) socket, msg_p, flags);
375 * Simulate a blocking sendmsg on the non-blocking socket.
376 * It's non blocking because it was set that way for recvmsg.
378 int rxi_Sendmsg(osi_socket socket, struct msghdr *msg_p, int flags)
380 fd_set *sfds = (fd_set*)0;
381 while (sendmsg(socket, msg_p, flags) == -1) {
383 rx_stats.sendSelects++;
386 if ( !(sfds = IOMGR_AllocFDSet())) {
387 (osi_Msg "rx failed to alloc fd_set: ");
388 perror("rx_sendmsg");
391 FD_SET(socket, sfds);
396 #elif defined(AFS_LINUX22_ENV)
397 /* linux unfortunately returns ECONNREFUSED if the target port
398 * is no longer in use */
399 if (errno != EWOULDBLOCK && errno != ENOBUFS && errno != ECONNREFUSED)
401 if (errno != EWOULDBLOCK && errno != ENOBUFS)
404 (osi_Msg "rx failed to send packet: ");
405 perror("rx_sendmsg");
408 while ((err = select(socket+1, 0, sfds, 0, 0)) != 1) {
409 if (err >= 0 || errno != EINTR)
410 osi_Panic("rxi_sendmsg: select error %d.%d", err, errno);
414 IOMGR_FreeFDSet(sfds);