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/cvs/IO-AIO/AIO.xs
Revision: 1.32
Committed: Mon Aug 22 23:20:37 2005 UTC (18 years, 8 months ago) by root
Branch: MAIN
Changes since 1.31: +118 -9 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #define _REENTRANT 1
2 #include <errno.h>
3
4 #include "EXTERN.h"
5 #include "perl.h"
6 #include "XSUB.h"
7
8 #include "autoconf/config.h"
9
10 #include <pthread.h>
11
12 #include <sys/types.h>
13 #include <sys/stat.h>
14
15 #include <unistd.h>
16 #include <fcntl.h>
17 #include <signal.h>
18 #include <sched.h>
19
20 #if HAVE_SENDFILE
21 # if __linux
22 # include <sys/sendfile.h>
23 # elif __freebsd
24 # include <sys/socket.h>
25 # include <sys/uio.h>
26 # elif __hpux
27 # include <sys/socket.h>
28 # endif
29 #endif
30
31 #if __ia64
32 # define STACKSIZE 65536
33 #else
34 # define STACKSIZE 4096
35 #endif
36
37 enum {
38 REQ_QUIT,
39 REQ_OPEN, REQ_CLOSE,
40 REQ_READ, REQ_WRITE, REQ_READAHEAD,
41 REQ_SENDFILE,
42 REQ_STAT, REQ_LSTAT, REQ_FSTAT,
43 REQ_FSYNC, REQ_FDATASYNC,
44 REQ_UNLINK, REQ_RMDIR,
45 REQ_SYMLINK,
46 };
47
48 typedef struct aio_cb {
49 struct aio_cb *volatile next;
50
51 int type;
52
53 int fd, fd2;
54 off_t offset;
55 size_t length;
56 ssize_t result;
57 mode_t mode; /* open */
58 int errorno;
59 SV *data, *callback;
60 SV *fh, *fh2;
61 void *dataptr, *data2ptr;
62 STRLEN dataoffset;
63
64 Stat_t *statdata;
65 } aio_cb;
66
67 typedef aio_cb *aio_req;
68
69 static int started, wanted;
70 static volatile int nreqs;
71 static int max_outstanding = 1<<30;
72 static int respipe [2];
73
74 static pthread_mutex_t reslock = PTHREAD_MUTEX_INITIALIZER;
75 static pthread_mutex_t reqlock = PTHREAD_MUTEX_INITIALIZER;
76 static pthread_cond_t reqwait = PTHREAD_COND_INITIALIZER;
77
78 static volatile aio_req reqs, reqe; /* queue start, queue end */
79 static volatile aio_req ress, rese; /* queue start, queue end */
80
81 static void free_req (aio_req req)
82 {
83 if (req->data)
84 SvREFCNT_dec (req->data);
85
86 if (req->fh)
87 SvREFCNT_dec (req->fh);
88
89 if (req->fh2)
90 SvREFCNT_dec (req->fh2);
91
92 if (req->statdata)
93 Safefree (req->statdata);
94
95 if (req->callback)
96 SvREFCNT_dec (req->callback);
97
98 Safefree (req);
99 }
100
101 static void
102 poll_wait ()
103 {
104 if (nreqs && !ress)
105 {
106 fd_set rfd;
107 FD_ZERO(&rfd);
108 FD_SET(respipe [0], &rfd);
109
110 select (respipe [0] + 1, &rfd, 0, 0, 0);
111 }
112 }
113
114 static int
115 poll_cb ()
116 {
117 dSP;
118 int count = 0;
119 int do_croak = 0;
120 aio_req req;
121
122 for (;;)
123 {
124 pthread_mutex_lock (&reslock);
125 req = ress;
126
127 if (req)
128 {
129 ress = req->next;
130
131 if (!ress)
132 {
133 /* read any signals sent by the worker threads */
134 char buf [32];
135 while (read (respipe [0], buf, 32) == 32)
136 ;
137
138 rese = 0;
139 }
140 }
141
142 pthread_mutex_unlock (&reslock);
143
144 if (!req)
145 break;
146
147 nreqs--;
148
149 if (req->type == REQ_QUIT)
150 started--;
151 else
152 {
153 int errorno = errno;
154 errno = req->errorno;
155
156 if (req->type == REQ_READ)
157 SvCUR_set (req->data, req->dataoffset + (req->result > 0 ? req->result : 0));
158
159 if (req->data2ptr && (req->type == REQ_READ || req->type == REQ_WRITE))
160 SvREADONLY_off (req->data);
161
162 if (req->statdata)
163 {
164 PL_laststype = req->type == REQ_LSTAT ? OP_LSTAT : OP_STAT;
165 PL_laststatval = req->result;
166 PL_statcache = *(req->statdata);
167 }
168
169 ENTER;
170 PUSHMARK (SP);
171 XPUSHs (sv_2mortal (newSViv (req->result)));
172
173 if (req->type == REQ_OPEN)
174 {
175 /* convert fd to fh */
176 SV *fh;
177
178 PUTBACK;
179 call_pv ("IO::AIO::_fd2fh", G_SCALAR | G_EVAL);
180 SPAGAIN;
181
182 fh = SvREFCNT_inc (POPs);
183
184 PUSHMARK (SP);
185 XPUSHs (sv_2mortal (fh));
186 }
187
188 if (SvOK (req->callback))
189 {
190 PUTBACK;
191 call_sv (req->callback, G_VOID | G_EVAL);
192 SPAGAIN;
193
194 if (SvTRUE (ERRSV))
195 {
196 free_req (req);
197 croak (0);
198 }
199 }
200
201 LEAVE;
202
203 errno = errorno;
204 count++;
205 }
206
207 free_req (req);
208 }
209
210 return count;
211 }
212
213 static void *aio_proc(void *arg);
214
215 static void
216 start_thread (void)
217 {
218 sigset_t fullsigset, oldsigset;
219 pthread_t tid;
220 pthread_attr_t attr;
221
222 pthread_attr_init (&attr);
223 pthread_attr_setstacksize (&attr, STACKSIZE);
224 pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
225
226 sigfillset (&fullsigset);
227 sigprocmask (SIG_SETMASK, &fullsigset, &oldsigset);
228
229 if (pthread_create (&tid, &attr, aio_proc, 0) == 0)
230 started++;
231
232 sigprocmask (SIG_SETMASK, &oldsigset, 0);
233 }
234
235 static void
236 send_req (aio_req req)
237 {
238 while (started < wanted && nreqs >= started)
239 start_thread ();
240
241 nreqs++;
242
243 pthread_mutex_lock (&reqlock);
244
245 req->next = 0;
246
247 if (reqe)
248 {
249 reqe->next = req;
250 reqe = req;
251 }
252 else
253 reqe = reqs = req;
254
255 pthread_cond_signal (&reqwait);
256 pthread_mutex_unlock (&reqlock);
257
258 if (nreqs > max_outstanding)
259 for (;;)
260 {
261 poll_cb ();
262
263 if (nreqs <= max_outstanding)
264 break;
265
266 poll_wait ();
267 }
268 }
269
270 static void
271 end_thread (void)
272 {
273 aio_req req;
274 Newz (0, req, 1, aio_cb);
275 req->type = REQ_QUIT;
276
277 send_req (req);
278 }
279
280 static void min_parallel (int nthreads)
281 {
282 if (wanted < nthreads)
283 wanted = nthreads;
284 }
285
286 static void max_parallel (int nthreads)
287 {
288 int cur = started;
289
290 if (wanted > nthreads)
291 wanted = nthreads;
292
293 while (cur > wanted)
294 {
295 end_thread ();
296 cur--;
297 }
298
299 while (started > wanted)
300 {
301 poll_wait ();
302 poll_cb ();
303 }
304 }
305
306 static void create_pipe ()
307 {
308 if (pipe (respipe))
309 croak ("unable to initialize result pipe");
310
311 if (fcntl (respipe [0], F_SETFL, O_NONBLOCK))
312 croak ("cannot set result pipe to nonblocking mode");
313
314 if (fcntl (respipe [1], F_SETFL, O_NONBLOCK))
315 croak ("cannot set result pipe to nonblocking mode");
316 }
317
318 static void atfork_prepare (void)
319 {
320 pthread_mutex_lock (&reqlock);
321 pthread_mutex_lock (&reslock);
322 }
323
324 static void atfork_parent (void)
325 {
326 pthread_mutex_unlock (&reslock);
327 pthread_mutex_unlock (&reqlock);
328 }
329
330 static void atfork_child (void)
331 {
332 aio_req prv;
333
334 started = 0;
335
336 while (reqs)
337 {
338 prv = reqs;
339 reqs = prv->next;
340 free_req (prv);
341 }
342
343 reqs = reqe = 0;
344
345 while (ress)
346 {
347 prv = ress;
348 ress = prv->next;
349 free_req (prv);
350 }
351
352 ress = rese = 0;
353
354 close (respipe [0]);
355 close (respipe [1]);
356 create_pipe ();
357
358 atfork_parent ();
359 }
360
361 /*****************************************************************************/
362 /* work around various missing functions */
363
364 #if !HAVE_PREADWRITE
365 # define pread aio_pread
366 # define pwrite aio_pwrite
367
368 /*
369 * make our pread/pwrite safe against themselves, but not against
370 * normal read/write by using a mutex. slows down execution a lot,
371 * but that's your problem, not mine.
372 */
373 static pthread_mutex_t iolock = PTHREAD_MUTEX_INITIALIZER;
374
375 static ssize_t
376 pread (int fd, void *buf, size_t count, off_t offset)
377 {
378 ssize_t res;
379 off_t ooffset;
380
381 pthread_mutex_lock (&iolock);
382 ooffset = lseek (fd, 0, SEEK_CUR);
383 lseek (fd, offset, SEEK_SET);
384 res = read (fd, buf, count);
385 lseek (fd, ooffset, SEEK_SET);
386 pthread_mutex_unlock (&iolock);
387
388 return res;
389 }
390
391 static ssize_t
392 pwrite (int fd, void *buf, size_t count, off_t offset)
393 {
394 ssize_t res;
395 off_t ooffset;
396
397 pthread_mutex_lock (&iolock);
398 ooffset = lseek (fd, 0, SEEK_CUR);
399 lseek (fd, offset, SEEK_SET);
400 res = write (fd, buf, count);
401 lseek (fd, offset, SEEK_SET);
402 pthread_mutex_unlock (&iolock);
403
404 return res;
405 }
406 #endif
407
408 #if !HAVE_FDATASYNC
409 # define fdatasync fsync
410 #endif
411
412 #if !HAVE_READAHEAD
413 # define readahead aio_readahead
414
415 static char readahead_buf[4096];
416
417 static ssize_t
418 readahead (int fd, off_t offset, size_t count)
419 {
420 while (count > 0)
421 {
422 size_t len = count < sizeof (readahead_buf) ? count : sizeof (readahead_buf);
423
424 pread (fd, readahead_buf, len, offset);
425 offset += len;
426 count -= len;
427 }
428
429 errno = 0;
430 }
431 #endif
432
433 /* sendfile always needs emulation */
434 static ssize_t
435 sendfile_ (int ofd, int ifd, off_t offset, size_t count)
436 {
437 ssize_t res;
438
439 if (!count)
440 return 0;
441
442 #if __linux
443 res = sendfile (ofd, ifd, &offset, count);
444
445 #elif __freebsd
446 /*
447 * Of course, the freebsd sendfile is a dire hack with no thoughts
448 * wasted on making it similar to other i/o functions.
449 */
450 {
451 off_t sbytes;
452 res = sendfile (ifd, ofd, offset, count, 0, &sbytes, 0);
453
454 if (!res && errno == EAGAIN)
455 res = sbytes;
456 }
457
458 #elif __hpux
459 res = sendfile (ofd, ifd, offset, count, 0, 0);
460
461 #else
462 res = -1;
463 errno = ENOSYS;
464 #endif
465
466 if (res < 0 && (errno == ENOSYS || errno == EINVAL || errno == ENOTSOCK))
467 {
468 /* emulate sendfile. this is a major pain in the ass */
469 char *buf = malloc (4096);
470 res = 0;
471
472 for (;;)
473 {
474 ssize_t cnt;
475
476 cnt = pread (ifd, buf, 4096, offset);
477
478 if (cnt <= 0)
479 {
480 if (cnt && !res) res = -1;
481 break;
482 }
483
484 cnt = write (ofd, buf, cnt);
485
486 if (cnt <= 0)
487 {
488 if (cnt && !res) res = -1;
489 break;
490 }
491
492 offset += cnt;
493 res += cnt;
494 }
495
496 {
497 int errorno = errno;
498 free (buf);
499 errno = errorno;
500 }
501 }
502
503 return res;
504 }
505
506 /*****************************************************************************/
507
508 static void *
509 aio_proc (void *thr_arg)
510 {
511 aio_req req;
512 int type;
513
514 do
515 {
516 pthread_mutex_lock (&reqlock);
517
518 for (;;)
519 {
520 req = reqs;
521
522 if (reqs)
523 {
524 reqs = reqs->next;
525 if (!reqs) reqe = 0;
526 }
527
528 if (req)
529 break;
530
531 pthread_cond_wait (&reqwait, &reqlock);
532 }
533
534 pthread_mutex_unlock (&reqlock);
535
536 errno = 0; /* strictly unnecessary */
537
538 type = req->type;
539
540 switch (type)
541 {
542 case REQ_READ: req->result = pread (req->fd, req->dataptr, req->length, req->offset); break;
543 case REQ_WRITE: req->result = pwrite (req->fd, req->dataptr, req->length, req->offset); break;
544
545 case REQ_READAHEAD: req->result = readahead (req->fd, req->offset, req->length); break;
546 case REQ_SENDFILE: req->result = sendfile_ (req->fd, req->fd2, req->offset, req->length); break;
547
548 case REQ_STAT: req->result = stat (req->dataptr, req->statdata); break;
549 case REQ_LSTAT: req->result = lstat (req->dataptr, req->statdata); break;
550 case REQ_FSTAT: req->result = fstat (req->fd , req->statdata); break;
551
552 case REQ_OPEN: req->result = open (req->dataptr, req->fd, req->mode); break;
553 case REQ_CLOSE: req->result = close (req->fd); break;
554 case REQ_UNLINK: req->result = unlink (req->dataptr); break;
555 case REQ_RMDIR: req->result = rmdir (req->dataptr); break;
556 case REQ_SYMLINK: req->result = symlink (req->data2ptr, req->dataptr); break;
557
558 case REQ_FDATASYNC: req->result = fdatasync (req->fd); break;
559 case REQ_FSYNC: req->result = fsync (req->fd); break;
560
561 case REQ_QUIT:
562 break;
563
564 default:
565 req->result = ENOSYS;
566 break;
567 }
568
569 req->errorno = errno;
570
571 pthread_mutex_lock (&reslock);
572
573 req->next = 0;
574
575 if (rese)
576 {
577 rese->next = req;
578 rese = req;
579 }
580 else
581 {
582 rese = ress = req;
583
584 /* write a dummy byte to the pipe so fh becomes ready */
585 write (respipe [1], &respipe, 1);
586 }
587
588 pthread_mutex_unlock (&reslock);
589 }
590 while (type != REQ_QUIT);
591
592 return 0;
593 }
594
595 #define dREQ \
596 aio_req req; \
597 \
598 if (SvOK (callback) && !SvROK (callback)) \
599 croak ("clalback must be undef or of reference type"); \
600 \
601 Newz (0, req, 1, aio_cb); \
602 if (!req) \
603 croak ("out of memory during aio_req allocation"); \
604 \
605 req->callback = newSVsv (callback);
606
607 MODULE = IO::AIO PACKAGE = IO::AIO
608
609 PROTOTYPES: ENABLE
610
611 BOOT:
612 {
613 create_pipe ();
614 pthread_atfork (atfork_prepare, atfork_parent, atfork_child);
615 }
616
617 void
618 min_parallel(nthreads)
619 int nthreads
620 PROTOTYPE: $
621
622 void
623 max_parallel(nthreads)
624 int nthreads
625 PROTOTYPE: $
626
627 int
628 max_outstanding(nreqs)
629 int nreqs
630 PROTOTYPE: $
631 CODE:
632 RETVAL = max_outstanding;
633 max_outstanding = nreqs;
634
635 void
636 aio_open(pathname,flags,mode,callback=&PL_sv_undef)
637 SV * pathname
638 int flags
639 int mode
640 SV * callback
641 PROTOTYPE: $$$;$
642 CODE:
643 {
644 dREQ;
645
646 req->type = REQ_OPEN;
647 req->data = newSVsv (pathname);
648 req->dataptr = SvPVbyte_nolen (req->data);
649 req->fd = flags;
650 req->mode = mode;
651
652 send_req (req);
653 }
654
655 void
656 aio_close(fh,callback=&PL_sv_undef)
657 SV * fh
658 SV * callback
659 PROTOTYPE: $;$
660 ALIAS:
661 aio_close = REQ_CLOSE
662 aio_fsync = REQ_FSYNC
663 aio_fdatasync = REQ_FDATASYNC
664 CODE:
665 {
666 dREQ;
667
668 req->type = ix;
669 req->fh = newSVsv (fh);
670 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
671
672 send_req (req);
673 }
674
675 void
676 aio_read(fh,offset,length,data,dataoffset,callback=&PL_sv_undef)
677 SV * fh
678 UV offset
679 UV length
680 SV * data
681 UV dataoffset
682 SV * callback
683 ALIAS:
684 aio_read = REQ_READ
685 aio_write = REQ_WRITE
686 PROTOTYPE: $$$$$;$
687 CODE:
688 {
689 aio_req req;
690 STRLEN svlen;
691 char *svptr = SvPVbyte (data, svlen);
692
693 SvUPGRADE (data, SVt_PV);
694 SvPOK_on (data);
695
696 if (dataoffset < 0)
697 dataoffset += svlen;
698
699 if (dataoffset < 0 || dataoffset > svlen)
700 croak ("data offset outside of string");
701
702 if (ix == REQ_WRITE)
703 {
704 /* write: check length and adjust. */
705 if (length < 0 || length + dataoffset > svlen)
706 length = svlen - dataoffset;
707 }
708 else
709 {
710 /* read: grow scalar as necessary */
711 svptr = SvGROW (data, length + dataoffset);
712 }
713
714 if (length < 0)
715 croak ("length must not be negative");
716
717 {
718 dREQ;
719
720 req->type = ix;
721 req->fh = newSVsv (fh);
722 req->fd = PerlIO_fileno (ix == REQ_READ ? IoIFP (sv_2io (fh))
723 : IoOFP (sv_2io (fh)));
724 req->offset = offset;
725 req->length = length;
726 req->data = SvREFCNT_inc (data);
727 req->dataptr = (char *)svptr + dataoffset;
728
729 if (!SvREADONLY (data))
730 {
731 SvREADONLY_on (data);
732 req->data2ptr = (void *)data;
733 }
734
735 send_req (req);
736 }
737 }
738
739 void
740 aio_sendfile(out_fh,in_fh,in_offset,length,callback=&PL_sv_undef)
741 SV * out_fh
742 SV * in_fh
743 UV in_offset
744 UV length
745 SV * callback
746 PROTOTYPE: $$$$;$
747 CODE:
748 {
749 dREQ;
750
751 req->type = REQ_SENDFILE;
752 req->fh = newSVsv (out_fh);
753 req->fd = PerlIO_fileno (IoIFP (sv_2io (out_fh)));
754 req->fh2 = newSVsv (in_fh);
755 req->fd2 = PerlIO_fileno (IoIFP (sv_2io (in_fh)));
756 req->offset = in_offset;
757 req->length = length;
758
759 send_req (req);
760 }
761
762 void
763 aio_readahead(fh,offset,length,callback=&PL_sv_undef)
764 SV * fh
765 UV offset
766 IV length
767 SV * callback
768 PROTOTYPE: $$$;$
769 CODE:
770 {
771 dREQ;
772
773 req->type = REQ_READAHEAD;
774 req->fh = newSVsv (fh);
775 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh)));
776 req->offset = offset;
777 req->length = length;
778
779 send_req (req);
780 }
781
782 void
783 aio_stat(fh_or_path,callback=&PL_sv_undef)
784 SV * fh_or_path
785 SV * callback
786 ALIAS:
787 aio_stat = REQ_STAT
788 aio_lstat = REQ_LSTAT
789 CODE:
790 {
791 dREQ;
792
793 New (0, req->statdata, 1, Stat_t);
794 if (!req->statdata)
795 {
796 free_req (req);
797 croak ("out of memory during aio_req->statdata allocation");
798 }
799
800 if (SvPOK (fh_or_path))
801 {
802 req->type = ix;
803 req->data = newSVsv (fh_or_path);
804 req->dataptr = SvPVbyte_nolen (req->data);
805 }
806 else
807 {
808 req->type = REQ_FSTAT;
809 req->fh = newSVsv (fh_or_path);
810 req->fd = PerlIO_fileno (IoIFP (sv_2io (fh_or_path)));
811 }
812
813 send_req (req);
814 }
815
816 void
817 aio_unlink(pathname,callback=&PL_sv_undef)
818 SV * pathname
819 SV * callback
820 ALIAS:
821 aio_unlink = REQ_UNLINK
822 aio_rmdir = REQ_RMDIR
823 CODE:
824 {
825 dREQ;
826
827 req->type = ix;
828 req->data = newSVsv (pathname);
829 req->dataptr = SvPVbyte_nolen (req->data);
830
831 send_req (req);
832 }
833
834 void
835 aio_symlink(oldpath,newpath,callback=&PL_sv_undef)
836 SV * oldpath
837 SV * newpath
838 SV * callback
839 CODE:
840 {
841 dREQ;
842
843 req->type = REQ_SYMLINK;
844 req->fh = newSVsv (oldpath);
845 req->data2ptr = SvPVbyte_nolen (req->fh);
846 req->data = newSVsv (newpath);
847 req->dataptr = SvPVbyte_nolen (req->data);
848
849 send_req (req);
850 }
851
852 void
853 flush()
854 PROTOTYPE:
855 CODE:
856 while (nreqs)
857 {
858 poll_wait ();
859 poll_cb ();
860 }
861
862 void
863 poll()
864 PROTOTYPE:
865 CODE:
866 if (nreqs)
867 {
868 poll_wait ();
869 poll_cb ();
870 }
871
872 int
873 poll_fileno()
874 PROTOTYPE:
875 CODE:
876 RETVAL = respipe [0];
877 OUTPUT:
878 RETVAL
879
880 int
881 poll_cb(...)
882 PROTOTYPE:
883 CODE:
884 RETVAL = poll_cb ();
885 OUTPUT:
886 RETVAL
887
888 void
889 poll_wait()
890 PROTOTYPE:
891 CODE:
892 if (nreqs)
893 poll_wait ();
894
895 int
896 nreqs()
897 PROTOTYPE:
898 CODE:
899 RETVAL = nreqs;
900 OUTPUT:
901 RETVAL
902