ViewVC Help
View File | Revision Log | Show Annotations | Download File | Root Listing
root/radiance/src/rt/raypcalls.c
(Generate patch)

Comparing src/rt/raypcalls.c (file contents):
Revision 2.3 by greg, Thu Jul 3 15:00:19 2003 UTC vs.
Revision 2.18 by greg, Fri Feb 8 18:27:31 2008 UTC

# Line 23 | Line 23 | static const char      RCSid[] = "$Id$";
23   *  The first step is opening one or more rendering processes
24   *  with a call to ray_pinit(oct, nproc).  Before calling fork(),
25   *  ray_pinit() loads the octree and data structures into the
26 < *  caller's memory.  This permits all sorts of queries that
27 < *  wouldn't be possible otherwise, without causing any real
26 > *  caller's memory, and ray_popen() synchronizes the ambient
27 > *  file, if any.  Shared memory permits all sorts of queries
28 > *  that wouldn't be possible otherwise, without causing any real
29   *  memory overhead, since all the static data are shared
30   *  between processes.  Rays are then traced using a simple
31   *  queuing mechanism, explained below.
32   *
33 < *  The ray queue holds as many rays as there are rendering
34 < *  processes.  Rays are queued and returned by a single
33 > *  The ray queue buffers RAYQLEN rays before sending to
34 > *  children, each of which may internally buffer RAYQLEN rays.
35 > *
36 > *  Rays are queued and returned by a single
37   *  ray_pqueue() call.  A ray_pqueue() return
38   *  value of 0 indicates that no rays are ready
39   *  and the queue is not yet full.  A return value of 1
# Line 43 | Line 46 | static const char      RCSid[] = "$Id$";
46   *      myRay.rorg = ( ray origin point )
47   *      myRay.rdir = ( normalized ray direction )
48   *      myRay.rmax = ( maximum length, or zero for no limit )
49 < *      rayorigin(&myRay, NULL, PRIMARY, 1.0);
49 > *      rayorigin(&myRay, PRIMARY, NULL, NULL);
50   *      myRay.rno = ( my personal ray identifier )
51   *      if (ray_pqueue(&myRay) == 1)
52   *              { do something with results }
# Line 51 | Line 54 | static const char      RCSid[] = "$Id$";
54   *  Note the differences between this and the simpler ray_trace()
55   *  call.  In particular, the call may or may not return a value
56   *  in the passed ray structure.  Also, you need to call rayorigin()
57 < *  yourself, which is normally for you by ray_trace().  The
58 < *  great thing is that ray_pqueue() will trace rays faster in
57 > *  yourself, which is normally called for you by ray_trace().  The
58 > *  benefit is that ray_pqueue() will trace rays faster in
59   *  proportion to the number of CPUs you have available on your
60   *  system.  If the ray queue is full before the call, ray_pqueue()
61   *  will block until a result is ready so it can queue this one.
# Line 81 | Line 84 | static const char      RCSid[] = "$Id$";
84   *              ray_psend(&myRay);
85   *      }
86   *
87 < *  The ray_presult() and/or ray_pqueue() functions may then be
88 < *  called to read back the results.
87 > *  Note that it is a fatal error to call ra_psend() when
88 > *  ray_pnidle is zero.  The ray_presult() and/or ray_pqueue()
89 > *  functions may be called subsequently to read back the results.
90   *
91   *  When you are done, you may call ray_pdone(1) to close
92   *  all child processes and clean up memory used by Radiance.
# Line 99 | Line 103 | static const char      RCSid[] = "$Id$";
103   *  If you just want to reap children so that you can alter the
104   *  rendering parameters without reloading the scene, use the
105   *  ray_pclose(0) and ray_popen(nproc) calls to close
106 < *  then restart the child processes.
106 > *  then restart the child processes after the changes are made.
107   *
108   *  Note:  These routines are written to coordinate with the
109   *  definitions in raycalls.c, and in fact depend on them.
110   *  If you want to trace a ray and get a result synchronously,
111   *  use the ray_trace() call to compute it in the parent process.
112 + *  This will not interfere with any subprocess calculations,
113 + *  but beware that a fatal error may end with a call to quit().
114   *
115   *  Note:  One of the advantages of using separate processes
116   *  is that it gives the calling program some immunity from
117   *  fatal rendering errors.  As discussed in raycalls.c,
118   *  Radiance tends to throw up its hands and exit at the
119   *  first sign of trouble, calling quit() to return control
120 < *  to the system.  Although you can avoid exit() with
120 > *  to the top level.  Although you can avoid exit() with
121   *  your own longjmp() in quit(), the cleanup afterwards
122   *  is always suspect.  Through the use of subprocesses,
123   *  we avoid this pitfall by closing the processes and
# Line 120 | Line 126 | static const char      RCSid[] = "$Id$";
126   *  of these calls, you can assume that the processes have
127   *  been cleaned up with a call to ray_close(), though you
128   *  will have to call ray_pdone() yourself if you want to
129 < *  free memory.  Obviously, you cannot continue rendering,
130 < *  but otherwise your process should not be compromised.
129 > *  free memory.  Obviously, you cannot continue rendering
130 > *  without risking further errors, but otherwise your
131 > *  process should not be compromised.
132   */
133  
134 + #include  "rtprocess.h"
135   #include  "ray.h"
136 <
136 > #include  "ambient.h"
137 > #include  <sys/types.h>
138 > #include  <sys/wait.h>
139   #include  "selcall.h"
140  
141   #ifndef RAYQLEN
142 < #define RAYQLEN         16              /* # rays to send at once */
142 > #define RAYQLEN         12              /* # rays to send at once */
143   #endif
144  
145   #ifndef MAX_RPROCS
# Line 160 | Line 170 | static int     r_recv_next;            /* next receive ray placement
170  
171   #define sendq_full()    (r_send_next >= RAYQLEN)
172  
173 + static int ray_pflush(void);
174 + static void ray_pchild(int fd_in, int fd_out);
175  
176 < void
177 < ray_pinit(otnm, nproc)          /* initialize ray-tracing processes */
178 < char    *otnm;
179 < int     nproc;
176 >
177 > extern void
178 > ray_pinit(              /* initialize ray-tracing processes */
179 >        char    *otnm,
180 >        int     nproc
181 > )
182   {
183          if (nobjects > 0)               /* close old calculation */
184                  ray_pdone(0);
# Line 185 | Line 199 | int    nproc;
199  
200  
201   static int
202 < ray_pflush()                    /* send queued rays to idle children */
202 > ray_pflush(void)                        /* send queued rays to idle children */
203   {
204          int     nc, n, nw, i, sfirst;
205  
206 <        if ((ray_pnidle <= 0 | r_send_next <= 0))
206 >        if ((ray_pnidle <= 0) | (r_send_next <= 0))
207                  return(0);              /* nothing we can send */
208          
209          sfirst = 0;                     /* divvy up labor */
# Line 219 | Line 233 | ray_pflush()                   /* send queued rays to idle children */
233   }
234  
235  
236 < void
237 < ray_psend(r)                    /* add a ray to our send queue */
238 < RAY     *r;
236 > extern void
237 > ray_psend(                      /* add a ray to our send queue */
238 >        RAY     *r
239 > )
240   {
241          if (r == NULL)
242                  return;
# Line 229 | Line 244 | RAY    *r;
244          if (sendq_full() && ray_pflush() <= 0)
245                  error(INTERNAL, "ray_pflush failed in ray_psend");
246  
247 <        copystruct(&r_queue[r_send_next], r);
233 <        r_send_next++;
247 >        r_queue[r_send_next++] = *r;
248   }
249  
250  
251 < int
252 < ray_pqueue(r)                   /* queue a ray for computation */
253 < RAY     *r;
251 > extern int
252 > ray_pqueue(                     /* queue a ray for computation */
253 >        RAY     *r
254 > )
255   {
256          if (r == NULL)
257                  return(0);
# Line 244 | Line 259 | RAY    *r;
259          if (sendq_full()) {
260                  RAY     mySend;
261                  int     rval;
262 <                copystruct(&mySend, r);
262 >                mySend = *r;
263                                          /* wait for a result */
264                  rval = ray_presult(r, 0);
265                                          /* put new ray in queue */
266 <                copystruct(&r_queue[r_send_next], &mySend);
252 <                r_send_next++;
266 >                r_queue[r_send_next++] = mySend;
267                  return(rval);           /* done */
268          }
269 <                                        /* add ray to send queue */
270 <        copystruct(&r_queue[r_send_next], r);
257 <        r_send_next++;
269 >                                        /* else add ray to send queue */
270 >        r_queue[r_send_next++] = *r;
271                                          /* check for returned ray... */
272          if (r_recv_first >= r_recv_next)
273                  return(0);
274                                          /* ...one is sitting in queue */
275 <        copystruct(r, &r_queue[r_recv_first]);
263 <        r_recv_first++;
275 >        *r = r_queue[r_recv_first++];
276          return(1);
277   }
278  
279  
280 < int
281 < ray_presult(r, poll)            /* check for a completed ray */
282 < RAY     *r;
283 < int     poll;
280 > extern int
281 > ray_presult(            /* check for a completed ray */
282 >        RAY     *r,
283 >        int     poll
284 > )
285   {
286          static struct timeval   tpoll;  /* zero timeval struct */
287          static fd_set   readset, errset;
# Line 279 | Line 292 | int    poll;
292                  return(0);
293                                          /* check queued results first */
294          if (r_recv_first < r_recv_next) {
295 <                copystruct(r, &r_queue[r_recv_first]);
296 <                r_recv_first++;
295 >                *r = r_queue[r_recv_first++];
296 >                                        /* make sure send queue has room */
297 >                if (sendq_full() && ray_pflush() <= 0)
298 >                        return(-1);
299                  return(1);
300          }
301          n = ray_pnprocs - ray_pnidle;   /* pending before flush? */
# Line 294 | Line 309 | int    poll;
309                  n = ray_pnprocs - ray_pnidle;
310          if (n <= 0)                     /* return if nothing to await */
311                  return(0);
312 +        if (!poll && ray_pnprocs == 1)  /* one process -> skip select() */
313 +                FD_SET(r_proc[0].fd_recv, &readset);
314 +
315   getready:                               /* any children waiting for us? */
316          for (pn = ray_pnprocs; pn--; )
317                  if (FD_ISSET(r_proc[pn].fd_recv, &readset) ||
# Line 354 | Line 372 | getready:                              /* any children waiting for us? */
372                  rp->slights = NULL;
373          }
374                                          /* return first ray received */
375 <        copystruct(r, &r_queue[r_recv_first]);
358 <        r_recv_first++;
375 >        *r = r_queue[r_recv_first++];
376          return(1);
377   }
378  
379  
380 < void
381 < ray_pdone(freall)               /* reap children and free data */
382 < int     freall;
380 > extern void
381 > ray_pdone(              /* reap children and free data */
382 >        int     freall
383 > )
384   {
385          ray_pclose(0);                  /* close child processes */
386  
# Line 375 | Line 393 | int    freall;
393  
394  
395   static void
396 < ray_pchild(fd_in, fd_out)       /* process rays (never returns) */
397 < int     fd_in;
398 < int     fd_out;
396 > ray_pchild(     /* process rays (never returns) */
397 >        int     fd_in,
398 >        int     fd_out
399 > )
400   {
401          int     n;
402          register int    i;
403 +                                        /* flag child process for quit() */
404 +        ray_pnprocs = -1;
405                                          /* read each ray request set */
406          while ((n = read(fd_in, (char *)r_queue, sizeof(r_queue))) > 0) {
407                  int     n2;
408 <                if (n % sizeof(RAY))
408 >                if (n < sizeof(RAY))
409                          break;
389 –                n /= sizeof(RAY);
410                                          /* get smuggled set length */
411 <                n2 = r_queue[0].crtype - n;
411 >                n2 = sizeof(RAY)*r_queue[0].crtype - n;
412                  if (n2 < 0)
413                          error(INTERNAL, "buffer over-read in ray_pchild");
414                  if (n2 > 0) {           /* read the rest of the set */
415 <                        i = readbuf(fd_in, (char *)(r_queue+n),
416 <                                        sizeof(RAY)*n2);
397 <                        if (i != sizeof(RAY)*n2)
415 >                        i = readbuf(fd_in, (char *)r_queue + n, n2);
416 >                        if (i != n2)
417                                  break;
418                          n += n2;
419                  }
420 +                n /= sizeof(RAY);
421                                          /* evaluate rays */
422                  for (i = 0; i < n; i++) {
423                          r_queue[i].crtype = r_queue[i].rtype;
424                          r_queue[i].parent = NULL;
425                          r_queue[i].clipset = NULL;
426                          r_queue[i].slights = NULL;
407 –                        r_queue[i].revf = raytrace;
427                          samplendx++;
428                          rayclear(&r_queue[i]);
429                          rayvalue(&r_queue[i]);
# Line 421 | Line 440 | int    fd_out;
440   }
441  
442  
443 < void
444 < ray_popen(nadd)                 /* open the specified # processes */
445 < int     nadd;
443 > extern void
444 > ray_popen(                      /* open the specified # processes */
445 >        int     nadd
446 > )
447   {
448                                          /* check if our table has room */
449          if (ray_pnprocs + nadd > MAX_NPROCS)
450                  nadd = MAX_NPROCS - ray_pnprocs;
451          if (nadd <= 0)
452                  return;
453 <        fflush(stderr);                 /* clear pending output */
454 <        fflush(stdout);
453 >        ambsync();                      /* load any new ambient values */
454 >        fflush(NULL);                   /* clear pending output */
455          while (nadd--) {                /* fork each new process */
456                  int     p0[2], p1[2];
457                  if (pipe(p0) < 0 || pipe(p1) < 0)
# Line 449 | Line 469 | int    nadd;
469                  if (r_proc[ray_pnprocs].pid < 0)
470                          error(SYSTEM, "cannot fork child process");
471                  close(p1[0]); close(p0[1]);
472 +                /*
473 +                 * Close write stream on exec to avoid multiprocessing deadlock.
474 +                 * No use in read stream without it, so set flag there as well.
475 +                 */
476 +                fcntl(p1[1], F_SETFD, FD_CLOEXEC);
477 +                fcntl(p0[0], F_SETFD, FD_CLOEXEC);
478                  r_proc[ray_pnprocs].fd_send = p1[1];
479                  r_proc[ray_pnprocs].fd_recv = p0[0];
480                  r_proc[ray_pnprocs].npending = 0;
# Line 458 | Line 484 | int    nadd;
484   }
485  
486  
487 < void
488 < ray_pclose(nsub)                /* close one or more child processes */
489 < int     nsub;
487 > extern void
488 > ray_pclose(             /* close one or more child processes */
489 >        int     nsub
490 > )
491   {
492          static int      inclose = 0;
493          RAY     res;
# Line 469 | Line 496 | int    nsub;
496                  return;
497          inclose++;
498                                          /* check argument */
499 <        if ((nsub <= 0 | nsub > ray_pnprocs))
499 >        if ((nsub <= 0) | (nsub > ray_pnprocs))
500                  nsub = ray_pnprocs;
501                                          /* clear our ray queue */
502          while (ray_presult(&res,0) > 0)
# Line 480 | Line 507 | int    nsub;
507                  ray_pnprocs--;
508                  close(r_proc[ray_pnprocs].fd_recv);
509                  close(r_proc[ray_pnprocs].fd_send);
510 <                while (wait(&status) != r_proc[ray_pnprocs].pid)
511 <                        ;
510 >                if (waitpid(r_proc[ray_pnprocs].pid, &status, 0) < 0)
511 >                        status = 127<<8;
512                  if (status) {
513                          sprintf(errmsg,
514                                  "rendering process %d exited with code %d",
# Line 498 | Line 525 | void
525   quit(ec)                        /* make sure exit is called */
526   int     ec;
527   {
528 +        if (ray_pnprocs > 0)    /* close children if any */
529 +                ray_pclose(0);          
530          exit(ec);
531   }

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines